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I received some URAC a couple of days ago and have been running tests to use the 1% ammonium chloride solution as a catalyst. So far I have had nothing but failures. Has anyone gotten a bad batch of resin from Nelson Paints?

I have mixed 10 grams of am. chl. with 100 ml of distilled water. I then mixed 35 ml of Urac resin with 7 ml of the catalyst solution. I have been testing the glue by spreading some on two popsicle sticks and clamping them together for 24 hours. The glue is setup in the film container that I poured the remaining into, but the sticks pop apart with  a torque on each end.

Any suggestions?  (Steve Trauthwein)

I am at work and my instruction sheet is stapled over my bench, but I believe it is 1 g of ammonium chloride to 10 cc of water to 100g of the URAC.  Jim Wilcox and several others have sent me slightly different formulas as far as units go, but I think they are primarily the same. I have used .5g to 5 ml to 50 ml as well with good results. I usually go with the bigger batches because I figure it reduces the need for dead on accuracy in the mix and also that the glue will need to be thrown out anyway, so why skimp on it? Good luck, it is a great glue when you find what works for you. BTW, I use tap water from my water filter. NO delaminations since the first batch or two. I also leave the strips out on the bench overnight before glue up so they aren't too dry.  (Bob Maulucci)

I had failures too until I went out and bought a scale. I only use URAC and have been fine with this ratio (this assumes you are using the commonly available white powder/distilled water mixture and not the walnut flour catalyst that comes with the resin);

.7 grams catalyst powder
10 grams h2o
100 grams resin

That ratio is roughly 10:1 resin to catalyst solution. Your ratio is 5:1 resin to catalyst solution. Too mucho amigo.

Try some bamboo on your next run with the 10:1 ratio and wipe them lightly with a damp sponge just before you slap some glue on. I kick my blanks further by heating them to 180 degrees for 2 hours. Keep an eye on the exp. date too. When all else fails, call Nelson.  (Eamon Lee)

Been using URAC since 1988, and no failures.  Until about 2 or 3 years ago, when John Channer sold me his leftover Ammonium Chloride, I used the standard walnut shell medium/hardner and did fine with it, but like the Ammonium chloride much better.  I premix the Ammonium Chloride 1:10 with distilled water, then use this 1:10 with the resin.  Works great and gives me plenty of working time.  I do use a good set of triple beam scales and get the mix dead on.  (Bob Nunley)

Eamon has it right. This is the suggested ratio from Nelson, and it works. I have a large supply of the ammonium chloride solution made up, which I made using distilled water, and on gram scales sensitive to the tenth. I then weigh the resin and add one tenth as much of the catalyst solution. I've never seen the need to dampen the strips, nor needed to heat cure the sections, though this can be useful if you are in a rush. I believe one hour at the specified temperature is sufficient, though it's been so long I'd have to look up the recommended time/temp ratio.  (Martin-Darrell)

This is something you'd need to confirm with Nelson but I'm pretty sure the shelf life of URAC will have been shortened recently and may shorten further in the future as the more dangerous chemicals in it are being reduced and replaced. Borden of UK has had to do this and my info from them was the requirement was due to findings and industrial requirements from the US relating to the use of formaldehyde.

My supplier is considering going out of it or mainlining thermosetting glues as his main custom is to plymakers and door framers who use a lot of this stuff as you can imagine but the shorter the shelf life the smaller the window of usefulness between the making of the glue and the using of it.

The shelf life of all UFs starts from the day it's made not the day it's opened.  Currently it seems somewhere between 3-6 months is about it. Like I say, check with Nelson for URAC.  (Tony Young)

I use Casco resin which I've been told is the equivalent to URAC-185.  I also use the 1% ammonium chloride/water mix, post heat, and have never had a rod failure caused by joint glue failure.  I've been unable to find a retail supplier, but Casco connected me with a Plywood manufacturer who doesn't mind me dropping in every 18 months to renew my supply.  When I first started to use it I was told by a Casco technician that the resin had a shelf life of 3 months at room temperature. However, every 10 degrees F drop doubles its shelf life. I store the resin in a fridge which raises the working life to 2 years.  The last few rods have been made with 18 month old resin.  How do you know when its too old?  According to the technician it will get lumpy.  If its still creamy smooth, then its still OK to use. (Ted Knott)

It was Bobbo "I'll be fine. Just give me a few minutes" Nunley who first put me on to refrigerating the CR-556, and it most definitely lengthens the shelf life. Right now I'm two and a half months past the expiration date, and have no doubts as to its still usefulness. I glued up blanks yesterday with it, and today they were as solid as could be. Bob had told me the same thing about the lumps in the resin, and his own experiences with that, so between him and the tech at Casco, I'll take that as the gospel.  (Martin-Darrell)

Speaking from a position of ignorance,  I too have wondered what happens to URAC as it ages.  What makes it no good after a period of time?  I never did think it was any good anyhow, but I am curious.  I have heard too that resorcinol has a limited shelf life, but I have glued rods up with 5+ year old resorcinol with out any effects.  It almost seems like a ploy to sell more urea formaldehyde.  (Ralph Moon)

It's definitely not a ploy to sell more glue.

UF is really good glue when it's within it's working life. It's almost as strong as resorcinol though the difference in strength is impossible to tell when it comes to fishing rods because they just don't get the stresses needed to make these glues fail as a scarfed wooden plank for a dingy may for example.  It makes for a slightly stiffer rod than resorcinol and resorcinol makes a stiffer rod than epoxy as far as I've been able to tell after making about 20 Driggs using different glues and comparing the results.

I use Borden two part liquid UF. It's great stuff and you don't need to buggerise about with micro scales and all that BS, you just use volume to measure it and proper is very easy.  The gist of what has happened as I've been told by Borden UK here in Australia is this:  I can't remember the name of the US government body concerned  but it's the one that defines what can and can't be used in the environment and what is and isn't allowed to be ingested by people but apparently it came out with a new set of rules defining how much formaldehyde could be used in UF glues in the US. Borden sell into the US so they have altered their composition to reflects these changes in their resin.  In order to allow the glue to achieve the same strength and pot life etc. with reduced formaldehyde has made the resin less stable chemically and as a result it's shelf life has been reduced.  Nothing has been altered with the hardener which has a shelf life measured in years.

I asked if keeping the resin in the fridge would help and they said no.  I asked if it would help a little and they said no. No idea if they're telling me this to cover their arses but I don't think so. I had some glue I bought before the alterations and used glue that was about 6 months old. Possibly it was 8 months old from when it was made and the blank failed utterly when I was testing it's spline. Now after having a series of disasters with epoxy once due to unannounced alterations of the makeup I am very prepared to accept changes get made to glue formula but this still this still surprised me because although the recommenced shelf life was 6-9 months I know I've used this glue up to 18 months old and this batch had been fine until now.

Looking into this is how I found out about the changes because I phoned Borden UK up in the UK to find out what was going on.  Now, URAC may not have changed but since all this trouble started in the US that's unlikely but possible so like I've written before, check with Nelson.

From my point of view because I get my glue directly from the makers here in Australia I know exactly what batch number the glue is and it's date of birth as it were and I can buy reasonably amounts, still a lot more than I can possibly use within it's shelf life but cheaply enough so it's still economically viable for me, my only fear is they will go out of it.

I like UF because it has a lot of really nice features.

Like I wrote before, I consider it to make stiffer rods than resorcinol or epoxy which I rather like.

Now as far as how do you tell if it's had it? Assuming you haven't tested it before using it on a rod which is bad practice now a days the rod will fail if the glue has had it. The decline between good and bad glue is very fast. I made a butt and tip within a day of each other, then made a second tip the next week. The butt and first tip wont fail no matter what I do to make them if they want to and the second tip failed just finding the spline. I rested the glue and it wouldn't even bond pine strong enough to resist breaking using just my hands.

So,  because I like UF despite all these potential problems what I now do is when I begin prepping the nodes on a new rod I make a test joint and set it aside until the next day and test it 24 hours or so after making it and break it.  24 hours is not actually the time you should allow for the glued blank but I figure if the joint holds within that time there can be noting wrong wit the glue.  If it does fail, I ditch the glue there and then and either get a new batch or use another glue depending on circumstances. The test joint is nothing more than two lengths of wood about a foot long and 2 x 1 inch. About an inch or two of one end of each piece is glued and clamped together.  24 hours later I put one end in the vise and hit the other with a hammer hard. If the joint fails at the glue line I ditch the glue, if the wood fails it's fine.  Not much to it really.

Resorcinol has a recommended life of about 2 2-1/2 years but as it's more stable than UF and as far as I've been able to tell hasn't been altered.  I have also used resorcinol that was way beyond it's recommended shelf life but I think that's only because the maker's have chosen to say 2 years to keep well within it's real shelf life, UF isn't like that as far as I can tell.  (Tony Young)

I just searched the archives and dug up only a couple of small threads on oven curing URAC glued rod sections.  I am wondering about the relative merits or drawbacks of this method of curing, as well as the types of times and temperatures that are typically used.  What I found varied from 28 minutes at 140 degrees to 1 hour at 175 degrees -- seemingly a large difference to me.  Perhaps the difference lies in the type of catalyst used?  Perhaps not?  Any info here would be greatly appreciated, as always!  (Carl DiNardo)

I don't think you need to heat cure UF glue at all. We may be talking different ambient temps but here the temp where I use the glue never falls below 5c nor above 35c and all I do is vary the hardener used. I use liquid UF and hardener at the ratio of 15:1 for around 20c and 20:1 when it's much hotter to try to keep the pot life about the same. Can't see why the resin being liquid or powder will make any difference apart from the mix ratio but in principal it should be the same. I find the issue isn't curing too slowly but too fast more often than not.

28 minutes @ 140f would be about 25 minutes more than it would take IMHO.

The times and need to heat cure sounds more like epoxy than UF to me.  (Tony Young)

The instructions that came with the first and only batch of URAC I bought (7 years ago, now use Epon) say that laminates can be fast cured with temps ranging from 125 for 14 minutes to 225 for 3 minutes, with an 1/8" depth to glue line. This information didn't seem to do me any good, I just let it cure in a warm room, or out in my shop in the summer, until at least the next day.  (John Channer)

I've glued up a few strips using a 2 to 1 mix and can't believe it is not fully cured by the time the varnish is dry enough to fish.  (Don Greife)

I use URAC and don't heat cure them. I find that in my shop, at around 60 degrees that the glue cures the best after two full days. I tried using Epon epoxy on the last few sets of blanks I made and I didn't like it. They felt "softer" than ones glued with URAC. I heat set the Epon blanks as per instructions.

I think the URAC tends to set up harder than the epoxy does and I like that. I also had a delimitation on one of the rods built with Epon and have never had any with URAC.

So, I guess I'll stick with URAC.  (Dave LeClair)

I agree with your findings about the finished product. There have been changes to the formula of UF glues over the last couple of years and all are detrimental to the shelf life of it. I messed with other glues and sometimes use Epon but I like UF so much better it's worth the hassle IMHO. The rods are a lot more crisp in action. Epon is fine with the para style rods but I made a Dickerson taper with it recently and it just didn't cut the mustard compared with the action I normally get with UF. The glue you use makes that much difference. A LOT more difference than any other single factor assuming you plane the strips properly and you are heat treating.  (Tony Young)

I only use URAC (or the Borden stuff) and use the "kick" catalyst. After glue-up I stick my heat gun in the end of a galvanized pipe and run it until it reaches 170-180. The other end is open and stays that way. I throw the strips in fat end first and cure them for 1/2 hour and flip them end for end and run them for one more 1/2 hour. I usually glue, sand and straightened in the same day. No problems to date.

George Maurer taught me that and it's great! He saved me a lot of trouble from the sounds of things!  (Eamon Lee)

Does anyone use URAC 185?  (Jerry Andrews)

I use it and like it. 20 minute working time, water cleanup, waterproof, easy mixing in small quantities, no heat setting requirements, sands/scrapes off easy. It has been used on cane for quite a long time.  (Don Greife)

This sounds great. Where do you get it? Do you wear gloves?  (Hal Manas)

The Nelson Paint Co. is a distributor.  (Don Greife)

I have been using URAC for the last several rods and must say I am impressed. Using the NH4CL the glue lines are .002". Upon gluing up the butt section for a 8.5' hollow built only .1 oz was added to the overall weight of the butt section. The original weight was 2.7 oz of the butt section hollowed. Before it was hollowed it weighed 3.2 oz. So hollow building the butt I shaved off .5 oz and gained only a .1 oz upon glue up. Pretty good. While rather cautious about using URAC I found it to be easier, less sticky then epoxy, and a breeze to clean up. It heat set fast but gave me plenty of time to bind. The blank is very rigid more so then those I have glue up with EPON. Another glue I have liked was Gorilla glue. Its down side is that it is messy and stains like no bodies business. It also makes up a stiff rod section.  (Adam Vigil)

Urea Formaldehyde adhesives rock!!

I use Perkins L-100.  I like everything about the stuff.  Keep it in the back of the fridge and it lasts and lasts.  Keep it cold and it has a really long pot life.  And water cleanup!  Who could ask for anything more?  (Brian Creek)

Where does one find Perkins L-100?  I get no hits on the internet.  (Neil Savage)

I buy it from Golden Witch.  Call Russ and ask for his adhesives FAQ sheet.  (Brian Creek)

I glued up 2 rods about 3 months ago with URAC and the ammonium chloride mix. Now I am ready to glue up 2 more and I cant find my paper work on what the ratio should be.  I do not want to do this by memory, if you know what I mean?

So what is the ratio of URAC to NhCl mix?  (Adam Vigil)

If you are using the Borden, go to the Golden Witch site for info.  (Bob Maulucci)

I think the URAC-185 is the same as UF-109. For the UF-109 I premix water with ammonium chloride crystals 20:1 by weight. Mix the glue with the Nh4Cl mixture 10:1 by weight.  (Ron Grantham)

This applies only to URAC 185 . Not Bordens CR-585.  The stock walnut flour catalyst  contains 13 percent by weight A.C. This amounts to .13 grams of A.C. per 10 grams of resin for the minimum 10 - 1 mixture.   I mix  100 grams  of resin to 2 grams A.C. (This allows for some leeway)  No need to add water.  Again this applies to URAC 185 ONLY.  (Dave Kenney)

I have used URAC for the last 5 rods with the ammonium chloride.  I have been very pleased with it easy to use and is very strong as well as heat resistant. In the past I have made several rods with Epon and Gorilla glue. Both are good choices but currently I am happy with the rigidity of URAC and the ease of clean up.

One of characteristic of URAC is that it does not have a extra long glue up time. With a normal situation it is fine, but currently things have been rather hot here in So. Ca. in the 100's. So gluing up is rather fast and furious. I normally dry up my sections pressed into my preset planing forms to end up  with a perfectly straight section. Due to the heat I decided to glue, roll and hang the section.

Now when the section is dried in the form giving me time to work on any kinks or twist the piece always comes out with no spine. This time though with the hanging to dry a spine was differently noticeable. As I heat straighten I was able to rid the section most of the spine.

I started to think maybe a spine in a cane rod is not due to weak bamboo, or how the wind blows in Asia or even because we did not pick strips from the opposite side of a culm. Could it be that a spine in the sections are due to tension stored in the cane due to twist and or kink strain not visible with the eye? Could it be heat straightening removes or adds to this strain? Could this be why when I glue up the rod in a form there is no spine because the strips are actually allowed to slip in relation to one another instead of simply bending them to appear straight?

I always wondered why that Mike Montagne would not heat straighten a section. Maybe he is right.

From now on I think I will glue up on cooler days so I can spend the time to manipulate the strips into position while the glue is still pliable. I think this may be more beneficial to the rod by eliminating stress that are seen in a crooked glue up section in need of heat straightening. Because when we are heat straightening we strips are bent and twist and are not able to slide as they should.  (Adam Vigil)

You may have a point here, but I think myself that a spine in a section be it bamboo or graphite is caused by dimensional errors.  If a strip is only a fraction different from its neighbor or opposite or whatever, I think that you will have a spine.  But then again the wind does blow.   (Ralph Moon)

Are you using URAC 185 or the Borden CR 585 ? I have found URAC gives a much longer working time. Also the walnut shell catalyst from Borden is unusable for rodbuilding I.M.O.

I have found a lot of "spine" in the blank is from the section not being straight (Assuming the strips were cut accurately).

I use a steel plate in my oven (3/4" x 4") and heat set my rods. I slide the steel plate halfway out, place the fresh glued and straightened sections carefully on it and slide it back in the oven. I have found  my rods come out straighter this way (I rarely have to straighten) than when I hang to dry, which I attribute to the steel being flat.  (Dave Kenney)

Ah, "spines" again...  In my experience, the only times I have found detectable spines in my rods were when I planed slightly less than perfect strips.  This would happen inadvertently when I was still planing on my adjustable forms (I now use the MHM), and would be the result of "chasing the apex," but not quite catching up with the perfect triangle before hitting my final dimensions.

I believe that what has happened is that while the walls of the planing form protect the dimensions of a strip's enamel surface, the interior has been cut to a less-than-accurate dimension.  Thus, when glued and bound, the flat-to-flat measurements may not reveal any imperfections, while the unseen interior contains areas that are not formed with perfectly full, isosceles triangles.  In short, I believe "spines" in bamboo rods are the result of unequally formed strips, whatever the possible causes, and are not the result of heating, gluing or straightening regimens.

I began to suspect this about six or seven years ago, and was the primary reason I switched to using the MHM.  Since that time, I have never had a rod with a detectable spine.  Also, during these more recent years, I've continued with my share of screw-ups during the binding and subsequent straightening process, but still no sets or spines.

That said, I think there also may be some reason to think that a spine could be the result of imperfectly straightened nodes -- especially in those    rods    whose    strips    have    been    soaked    and   then heat-straightened with a vise.  The process may seem to have removed the "kink" because the strip is so pliable and the vise is so strong, even while not permanently accomplishing that mission.  Subsequent heat straightening after gluing may allow the kink to reassert itself in the form of a set or a spine.

In short, I believe that a truly well-made bamboo rod will never exhibit a detectable spine.  I also believe that accomplishing this should become a rod maker's ultimate objective, as the presence of a spine can translate into only one thing -- potentially uneven loading that results in inaccurate casts.  (Bill Harms)

Actually Bill that is what I was trying to tell Adam.  (Ralph Moon)

Good observations, I believe you are on to something and will add it to my list of things that make me go.... Hmmm?

What I observed is while the strip had a slight bow and minor twist there was an obvious spine. As the bow and twist was remove the spine greatly decreased to a slight bump.

I no longer chase angles when making strips I have been making them with a vertical end mill "ALA Milward" and Isosceles is the rule. It is so easy it almost feels like cheating.  (Adam Vigil)

Yes, spines again...

What's wrong with a spine? As long as you use it to your advantage. One of my rodmaking experiments that I thought turned out well is a 5 ft. one piece rectangular quad. Rectangular in cross section to make sure it bent only in one plane - a built in spine if you want to think of it that way. In actual use I wouldn't say the rod itself is more accurate, but I can feel a torque or twist from the handle if the cast isn't going the way the rod is pointing, so I can feel more positively if the cast is going off or not and false cast to straighten it out.  (Darryl Hayashida)

My observation is that most of the time when there is a very apparent "spine", in fact this is a bend in the section to which the blank will naturally turn. Sure, there does occur spine in bamboo blanks, but I've never found it to be as pronounced as in graphite rods. Were this to ever be the case, I'd seriously consider trashing the blank.  (Martin-Darrell)

Just my 02 cents.

I have found that if I don't heat treat properly before I hand plane the strips I end up with some slight sets or spine after fishing the rod. It is also easy to  use the heat gun, carefully, to again straighten the rod, but in time the set will return. Since I have been correctly heat treating and keeping the rod in a controlled dry atmosphere before gluing and varnishing the sets, if any, have been practically nil.  (Jack Follweiler)

I hear what you are saying. In the situation I am speaking about sets are not an issue. I learned early on to avoid sets good cane and heat treatment was needed. Basically what I see is when the blank has a slight bow due to glue up it will show a spine. As I remove the bow the spine dramatically decreased.

And as Ralph and Bill point out if the dimension are not dead on it also will cause a spine. But then again if I used splines that are not equally perfect I would kick my own ASS!  (Adam Vigil)

How did those old and famous rod companies get away with using strips from different culms and turned out such nice casting rods? In many cases, the strips were even way off on flat-to-flat measurements.  (Steve Weiss)

Sure the rods of days past were off dimensionally and cast fine, but our goal as makers are to try to hit the numbers dead on and eliminate all those little things that can add up. A rod is more then sum of it parts. If we are able to understand what causes things such as a "spine" in a section or a tip that will not track vertically we may not end up with the finished product we are trying to create. Sometimes the rods we make are not what we WANT but rather they are the rods we GET!

The difference between a good rodmaker and a rod manufacturer is the details. Most rodmakers can glue up a section with glue lines, spine, crooked, poorly finished with a Zebco reel seat and a foam grip and it will cast fine.  (Adam Vigil)

From an objective and scientific point of view I have to disagree with:  "A rod is more then sum of it parts. " A rod is a sum of its parts and the physical laws that relate them.  Anything additional is totally subjective. However, enjoyment of a rod esthetically and as a fishing tool is also subjective. If it appeals a maker to make rods only from culms that come from and enchanted bamboo forest and it makes him happy, so be it!  (Doug Easton)

I think it's because some of the old tapers were truly excellent. So, even with the imperfections that went along with the older production rods, a great many of them cast very well indeed (though many, even those called by the same model, do not).  The point is, we don't have to accept that level of quality control just because it's all a production profit-margin could allow.  You can build that same taper  (whichever one you prefer) and get it dead on -- the way it is supposed to be -- and it will be a better casting rod than that of your favorite old master.  Why should we accept something less than the best if we don't have to?  Spines are anathema, and we needn't think of them as harmless just because one often finds them even in the best of the old rods.

Of course, not all spines are ruinous -- there are degrees of "acceptability." But even so, why not do everything possible to learn how to avoid what we needn't accept?  (Bill Harms)

Just playing devils advocate here, but...

Aren't there certain uses where a spine in the rod could be good thing? Perhaps to focus energy on one specific plane? Maybe to enhance a particular characteristic you may find desirable? Maybe to achieve that little extra "oomph" for distance?  (Dewey Hildebrand)

..Or maybe to make the rod bend more, thus giving the illusion of a larger fish.  (Denis Dunderdale)

This is true. But then again we are ending up with rod we get and not the rod we wanted. Still is good and fishable but I guess we always go back to the drawing board.  (Adam Vigil)

To those rodbuilders that use URAC 185 with a hardener made up of ammonium chloride and distilled water, my question is why?  I am just wondering what are the benefits of this hardener as opposed to the walnut shell hardener that comes with the glue.  I have been using the walnut hardener for years and have not had any failures yet.  Just curious as to why it may be a better alternative.  (Robert Cristant)

The ammonium chloride crystals are the catalyst and are present in the crushed walnut shells. If you obtain ammonium chloride crystals and mix one part of crystals to 20 parts of water, by weight, you will have a liquid catalyst. Mix one part of the catalyst with 10 parts of glue, by weight, to obtain a thin, transparent glue.

No solid filler means less chance of dimensional change when gluing. However, without the walnut flour, you can't expect to fill gaps so your angles must be exact.   (Ron Grantham)

I don't use URAC anymore (I use Titebond II Extend) but you may be interested in knowing that the late Sam Carlson who used URAC tried the ammonium chloride solution on one rod before going back to the Walnut Shell formula. The argument most people make is that the walnut shell formula adds a couple thousandths to the dimension of the taper. I used to say "so what."  (Marty DeSapio)

For any of the other Canadians on the list that use Ammonium Chloride as the catalyst for their URAC, can any of you point me in the right direction to purchase some.  Any help would be greatly appreciated.  (Robert Cristant)

You could try here https://www1.fishersci.com/index.jsp  (Daniel Durocher)

I bought mine at a drug store (London Drugs, downtown Vancouver). The pharmacist ordered it in for me.  (Ron Grantham)

Sifting is a good idea to remove chunks of walnut shells but the little white crystals are removed. They are are catalyst.

It is really tough to get them back into the sifted walnut in anything like a homogenous mixture. In larger quantities of glue/catalyst (1 quart Vs. a bunch of tablespoons) it would hardly matter. But in the smaller quantities that we tend to use, it is truly a tough job to get the same amount of catalyst after sifting.  (Don Anderson)

I'm planning to purchase some URAC from Nelson Paint.

I was wondering if I need to purchase the hardener as well. Also, how many rods should I expect to get out of say the pint size?  (Jim Lowe)

I believe so Jim. Buy a quart or pint of URAC and a pound of hardener. (Now, if you want to use Ammonium Chloride, you may not need the walnut flour hardener).   (Bob Maulucci)

Remember that the stuff has a limited shelf life.  If you start buying a larger amount the problem will  not be how many rods the glue can do, but rather how many rods you have ready to do.  Get yourself an accurate gram scale, too.  (Carl DiNardo)

Exactly, that is why I thought the smallest amounts would be good.  (Bob Maulucci)

If you have a cool place to store it the shelf life is longer.  I have an older refrigerator that I store mine in and have had it for close to two years now and it is still fine.  (Robert Cristant)

Although I am still seething over that 90% of the fish thing, in keeping with the spirit of the list, I will say that I bought a quart of URAC in October,  glued up eight rods. Threw away most of two, and still have plenty left.  I know the shelf life is only a year, but the pint I had previously seemed OK for two years. The walnut flower comes with it.  Most people use ammonium chloride, as some have folks say the walnut flower has large pieces which can result in glue lines. I'm thinking of using the walnut because I think ammonium chloride gives glue lines.  <g>  That's a joke on me.

Someone, can't remember who, said to add a drop of walnut flower to the mix even if using ammonium. I will try that next. But I think you must sift it if you do decide to use it.  (Mike Canazon)

Thanks Mike and thanks to all who responded. I presume that the  walnut flower is the hardener or a least that's the vibe I'm getting. I'll make sure I get some.  (Jim Lowe)

Actually Jim, the walnut flour is not the hardener (catalyst), but it is mixed with ammonium chloride which is the catalyst.  The walnut shell flour is actually a gap filler.  The little white crystals referred to when you sift the flour should be put back in because that is the ammonium chloride, and will dissolve when you mix with the resin.  The reason it is advisable to sift the flour is to rid the mix of any larger shell particles that may leave you with glue lines.

The shakedown is that if you don't fully trust your planed surfaces to be true, you should utilize the gap filling that the walnut shell flour provides.  The drawback is potential glue lines because of the filler.

If you trust that your planed surfaces are perfect then most UF users tend to say just to use the ammonium chloride (available as a separate product, no need to sift all of your shell flour for it).

It's potentially a risk/reward scenario.  (Carl DiNardo)

The late Sam Carlson, one of the all time great rodmakers tried the Ammonium Chloride instead of the  walnut flour for a very brief period. Didn't like it and went back to the Walnut Flour. Go figure?  (Marty DeSapio)

If you sift the walnut flour, don't throw out the little white particles, that's the ammonium chloride crystals which is the catalyst.  (Ron Grantham)

In 25 years of using URAC 185 for laying up veneer and rodmaking I have yet to encounter any chunks in the Walnut shell flour. I stopped sifting 8 years ago. Now that stuff you get with Borden’s CR 585 is another story, it is more like sawdust, not wood flour. I think it is unusable for rodmaking.  (Dave Kenney)

What do you use to sift the flour?  (Scott Grady)

I use an old flour sifter followed by a homemade sifter made with a dense screen and a wooden frame for resorcinol powder.  You could buy a set of sifters (I think they're called graders) from a chemical supply house, maybe Fisher Scientific.  (Joe West)

An old nylon stocking from my wife.  (Ron Grantham)

Nelson will give you the amount of catalyst appropriate for the amount of resin you buy. The price is the same whether or not you get the hardener (Weird but true) so you may as well get it.  URAC mixed with the walnut powder is excellent for gluing cork, and reel seats, so it is worth having even if you go the straight  Ammonium Chloride route.

100 grams of resin is just under 3 ounces (Liquid measure), I can normally do 2 rods with this, if I am careful.

The shipping cost just about doubles the cost of the glue if you buy single cans. Cans should last at least a year from purchase date.  (Dave Kenney)

I have an unopened can of URAC 185 that has been in the refrigerator since I bought it a year ago January.  Am I safe to use it or should I trash it and buy a new quart?  (Bob Williams)

Check to see if it lumpy.  That is the general rule of thumb.  There may be more specific advice on the tips site, but my can is now over 2 years old.  It has been stored in the fridge and I just used it a few weeks ago and it worked fine.  No lumps.  (Mark Babiy)

I decided to go right to the source; so I called Nelson Paint and they told me it would be fine.  They indicated that URAC is a heat sensitive glue and refrigeration is the best way to store it.  They also told me the shelf life would be very limited if stored above 70 degrees (which for some is room temperature).  (Bob Williams)

As a newcomer to rodbuilding, I have mainly been lurking around for the past few months as a worked through the progression (thanks to Aaron for asking many of the questions I was too afraid to ask). But I have just completed my final planing of rod #001 and am having trouble finding URAC 185 in any of the local hardware stores. One "glue expert" recommended DAP Weldwood plastic resin glue as a good substitute. He said it was a comparable glue. I was wondering if anyone has used this glue or had any other glue recommendations for me. I keep looking at that blank, ready to be glued and am excited to finish it off, but don't want to make a crucial mistake on glue selection. Any feedback would be appreciated.  (Wade Turner)

I use the DAP Weldwood Plastic Resin Glue exclusively on my rods.  So far nearly 50 rods glued up with it and no problems.  There are two versions of the glue, one natural color and the other is a more brown color.  The brown matches in with the cane better in case of a pesky glue line here and there.

I also like it for it's pot life.  I normally glue up 4-5 rods at a time, and at 70 degrees the glue has a 4 hour pot life, so I don't have to feel rushed.  However, once you smear the glue on the strips, be prepared to bind immediately.  For some reason it starts to tack pretty quickly once applied.

Another advantage of the DAP.  You can remove the binding cord after 12 hours and start sanding.

It also cleans up with water.  So, once I am done binding, a rag with some water is all it takes to clean my binder.  I also place a bucket of water below my binder and suspend the weight in the water.  The binders belt cord passes through the water so I can glue 4-5 rods without changing the belt.

A sponge and some lukewarm water to wipe the bound up blank before rolling and hanging will eliminate a lot of the hard chore of getting glue off the blank after you take it out of the string.  (Joe Byrd)

In addition to Joe's advice, I would suggest the following:

The glue is comparable to URAC in strength and hardness, but it is  not as heat resistant.  Straighten carefully with modest heat.  There is a definite shelf life, which is affected by exposure to  atmospheric moisture. Store it in a Mason Jar or something similar.  The plastic tub it comes in is garbage. Never use it unless you glue  up some test pieces the day before. I usually glue a couple 3/4" pine  sticks together. the sticks are about 1 foot long, and I overlap them  about 3" and glue the overlap. after 24 hours, pull them apart. If  wood splinters are drawn away from the sides of the glue joint, the  glue is still good.

Formaldehyde glues need moisture to work. If you just heat treated  the cane, it's too dry. Apply some moisture to the strips with an  atomizer, or a paintbrush dipped and shaken dry before gluing. Wait  10-15 minutes. there should be no standing water, but he cane should  be darkened slightly from the moisture. (Tom Smithwick)

Being that I've only completed two rods I'm no expert in this matter.  But I'll tell you what I've done.  After receiving many good reports from fellow list members on Poly Glues I used Elmers Pro Bond on my first two rods and they turned out beautiful.  It's a Poly Glue that's available at any hardware store.  It has a very long open time which I liked with my first rods.  I can't tell you how nervous I was smearing glue on those first strips (so many hours that could have been ruined).  The Probond gave me lots of time to make sure I got things right.

As an aside, I've almost got rods 3 and 4 ready to go and I am planning on using URAC 185 on those.  Not that I didn't like the ProBond, but rather because I want to try out several different methods for many of the aspects of rodbuilding so I can settle on what I like best.  I don't think URAC is sold in hardware stores (I could be wrong), but that you seen to order it from Nelson Paints in Iron Mountain, Michigan.  (Aaron Gaffney)

I second Aaron's recommendation of Elmer's Probond polyurethane.  It's now sold as "Ultimate Glue". I used resorcinol on my first few rods and was always real nervous about getting everything right in the 15-20 minutes of working time you had.  Polyurethanes are waterproof, require no mixing, have no grit in them, are easy find and inexpensive to buy, and give you 2-3 hr of working time.  I use it for gluing up blanks, gluing up grips, and gluing on ferrules (you might not want to use it on ferrules because it takes a lot of heat to get them off).

I highly recommend them for anyone,  but especially for beginners.  Once you're comfortable with the process of gluing up a rod, then you might want to experiment with other adhesives.  (Robert Kope)

You can order the URAC 185 from Highland Hardware in Atlanta and they will ship to you. I have had no problems with them, plus they have a lot of other neat stuff.  (Gary Jones)

You won't find URAC in the hardware store, it has to be ordered from Nelson Paint, go to the RODMAKERS site and look around in there, somewhere is their address and phone number. Many use Epon or Nyatex epoxy, both of those have to be ordered also. Of the off the shelf glues, polyurethane glues, such as Gorilla glue, seem to be popular as are the  exterior wood glue like Titebond II.  I've tried Weldwood, and it does work, but the open time is very short and I thought it left noticeable glue lines.  (John Channer)

I  just took  a rod  out of  the string  today that  I glued  up  with CR-591 and it totally delaminated as I was sanding the blank. The rod was in the string 72 hours. The glue was a fresh batch and mixed with the walnut shell catalyst. Shop temp was about 65  - 70 degrees and about 50% humidity. This is the second delaminate I have had with CR-591. I had a tip delaminate about a year ago using a different batch, reglued it after cleaning it back up and it seem to be holding up OK after a seasons use. I spent this afternoon separating the splines and used a Lie-Nielsen scraper and sandpaper to clean all the residual glue off and want to reglue the sections. Needless to say I'm gonna try a different glue. Anyone tried Titebond III. I checked the tips archives and found mention of Titebond II and extend but nothing of Titebond III. Any and all info will be appreciated.  (Mark Heskett)

I have tried Titebond III, however I thought it set up too fast to allow much straightening after glue up.  Also it is quite thick and I ended up with a small glue line something which hasn't happened to me with Titebond II Extend which is thinner.  I have been very happy with Titebond II Extend.  It has a much more reasonable working time and I have made about a dozen rods and have had no problems with it.  You can heat it (carefully) to straighten after glue up.  I have tried to break some of the cut off end pieces and they break at spots other than the glue line, so that leads me to believe that the glued area is as strong or stronger than the bamboo itself.  I coat my rods with 4 coats of spar varnish on the butt sections and 3 coats on the tips so I think they are well sealed.  (Tom Mohr)

Isn't the CR-591 a similar glue to one of your favorites? <g> (Harry Boyd)

PS -- Mark, give Epon a try.

Sounds like an experience I once had with a Glurac which shall be nameless.  (Ralph Moon)

I’m with Harry and others regarding EPON.  Not to rain on your parade but maybe you better do a test glue-up with whatever your new adhesive is to see if it’s compatible with the CR591 residues still in the strips.  You’ll never remove all the residue and it may cause and inferior bond even if everything else goes right.  I’d hate to see you spend all the effort in gluing up your rod and finishing it to find it fails at some later date. You might then put the blame on EPON or Titebond when in fact it was the original attempt that caused the problem.  At that pointy you might think NO adhesive works!  (Al Baldauski)

I am sure that your room temperature is too low. It needs to be above 70 degrees F. I keep my URAC (CR-591) in the refrigerator, and bring it out the day before in the house to warm to room temperature (instructions say glue must be above 70 degrees F) before use.  I keep my shop temperature above 70 degrees during glue up and humidity in the 60-65% level. I use a shop propane heater for warmth that puts combustion moisture in the room. I have built 7 rods with the URAC and not had any problems and am ready to glue up another 5 or 6 in the next week. It is very important to have a very precise glue mix based on WEIGHT not Volume (I use a digital scale). Here is what I use: Resin: 100 grams to Catalyst: 15 grams.  It is my opinion that one must use a good scale to insure this glue ratio. This is a 6.7 to 1 ratio. You can scale this weight ratio up or down as you wish. I let my rods sit for about a week in my house before removing the strings where the temperatures are in the lower 70's. I also wipe my rods down with a wet sponge right after glue up while the rod is in the strings, along with straightening (rolling slapping, etc). This process removes the excess glue on the rod surface but at the same time enhances the local rod moisture content that helps setting and bonding in my opinion.

Hope this might help.  Sorry to hear you have not been successful with your first several rods.   (Frank Paul)

I glued a rod with URAC under John Long's tutelage.  We put it in a heat gun oven at 115 degrees F. for an hour to "encourage" it.  That was all it took.  (Neil Savage)

What's the shelf life of URAC?  The only failure I've ever had was with this stuff & that was probably because of temp.  I've had a can in the back of the fridge for several years.  Do I dare use it.

I've been using Nyatex for the last few years without a problem.  (Ron Larsen)

From the Cytec web site:

Useful life of URAC 185 resin also depends upon the temperature to which it is exposed:

Temperature Useful Life

60°F 12 months

75°F 6 months

90°F 3 months

I guess you'd have to do a test to be sure it's still good.  (Neil Savage)

I've kept URAC 185 (the liquid part) in the refrigerator for a couple of years and used it with no problems. Just let the liquid warm up to room temperature to about 60F before using.  (Ray Gould)

I got some information from Borden back when they went to CR-591.  I graphed out what little information I could get and it suggests that 10 to 12 months at 40 degrees F.  I have used it out to 6 to 8 months without a problem. I have some old stuff that I should make up and see how it holds - probably 3 years old or so and been refrigerated in my shop. Don't put it in the SO's fridge.  (Frank Paul)

Webmaster comment:  I asked Frank about this post.  He replied with the following:

I suggest that this Borden adhesive is no longer sold by Golden Witch. I have had trouble with it because they have reduced the formaldehyde content. I am switching to Nelson Paints URAC 185 which is a similar material with correct formaldehyde content. I treat it the same way with refrigeration holding when not in use as I describe in this email.

A couple other points on the Urea Formaldehyde glues. I think a lot  of the failures are caused by gluing up dried strips. If you just  heat treated the cane, you need to introduce some moisture. The cane  has to be somewhere near 8 % moisture for the glue to work. Unless  you wait a couple months after heat treating, you won't be there.  I  have seen John Zimny use a perfume atomizer to spray water. I dip a  household paintbrush in water and shake out as much as I can. You  don't want loose water, but the strips should look damp. Let it soak  in for 10 minutes or so.

I never use these glues without testing. The day before using the  glue, prepare a couple 1x1x18" wood strips. Overlap them about 6" in  the center, and glue and clamp. After 24 hours, break them apart, and  see if you pull fibers out of the wood, or if the glue joint just  fails. If the glue is not stronger than the wood, don't use it.  (Tom Smithwick)

I'm thinking of using URAC for gluing but don't want to pay big money for a balance.  What are some cheaper alternatives.  I am thinking a $30 digital scale that measures in lbs. and grams from Target?  Any other suggestions in this ball park?  (Matt Baun)

I use a grain scale left over from my reloading days.  You can pick these up pretty cheaply.  (Ron Larsen)

On the URAC 185 from Nelsons the say you can mix 13 parts powered hardener to 100 parts liquid resin by weight or one loose measure of hardener to two measures of liquid. I have a triple beam scale and I checked both the measure against the weight.  Figured it's a lot easier to measure by volume than weight. I made one rod using this mixture and then found many were using 4 part resin to 1 part powder instead, so I made one using that ratio and it worked well and was easier to work with.

The only drawback was I had to buy my wife a new set of measuring spoons after I tried this, but still better than spending the money on a scale.  (Gary Jones)

Make a balance beam scale from I-beam curtain rod, a broomstick or any other material, with a pivot in the middle and some hooks on the ends with cups to hold the glue. Then get eleven wood screws, metal screws, bolts, nuts, washers, or whatever, all the same size, and put ten of them in a cup on one side of the beam, and the equivalent weight of glue at the other end. Then add one more screw, nut, or whatever you used, and add the equivalent weight of catalyst. That's ten to one by weight.  (Ron Grantham)

A balance beam is nice to have.  If your only need for the scale is to weigh URAC and its catalyst, it is kind of similar to feeling the need to buy that Harley so you can go to the store for a loaf of bread.

URAC   185   is   available   from  Nelsons.   Phone  no.  is 906.774.5566.  It is available in pints and quarts.  Buy two, as freight is almost as much as the material.

Now:  the stuff they send you in the bag to mix with the glue is a mixture of the catalyst along with pecan shells or walnut shells or the like.  Seems to me that the catalyst could settle out.  Or move around.  Something like that.  My point?  I don't think gnat's ass accuracy in the mixing ratio is that important.  It has to be worker bee proof to a point.  Slightly overcatalyzing or undercatalyzing will be tolerated by the glue.  The mix ratio is NOT the 300 pound green monster under your bed when it comes to glue up. The real catalyst for the resin is Ammonium Chloride.  You can buy the super "catalyzing salts" from your supplier for the big bucks, or order from The Science Company at $11.95 for a half pound, near lifetime supply.  Phone: 800.372.6726

2 ounce plastic "portion cups" are great for mixing it.  They are sold at Costco, or any Cash and Carry.  Pour the URAC up to the line just below the top of the cup.  That's 50 grams.  Then measure out .5 gram on your reloader scale or put a popsicle stick into the jar of Ammonium Chloride and bring out a rounded portion about an inch long.  That's really close.  Stir it in, wait 5 or 10 minutes for the glue to cross link, then glue up.  Note that the ratio for using just the Ammonium Chloride  is much less than the 10:1 for the factory supplied powder mix.

You get about 16 rod's worth from a quart of the glue.  Buck and a half to two bucks per rod.  If you are worried about working time, just glue up one section at a time.  Cleaning up the binder is not fun, but it isn't stressful.   Straightening three rod sections that are twisted, warped and set because you insisted on gluing up everything at once IS stressful.  So I'm told.  Mine come out of the binder perfectly straight every time.  'Cept for this one time.  (Chris Raine)

I use the URAC 185 with the ammonium chloride. How do you measure by weight or by volume? And what ratio? Do you heat cure the URAC 185?  If yes how long?  (Olaf Kundrus)

I have used the smallest measuring spoon in a set, I think it’s 1/8 teaspoon of ammonium chloride with 6 cc. of hot water to make a solution. I then use 2 cc. of this solution per 4 teaspoons of URAC I then heat set the sections at 150 for 1 hour. When blanks come out of the oven you can sand the string off and continue to work on them. I use a syringe to measure the liquid. This has worked out for me for quite some time.  (Joe Arguello)

I use 2 (liquid) to 1 (powder). I have use 3 to 1 and 4 to 1 before. No heat. I do place in my hanging area at about 100 degrees so if you call that heat that that's it. it's really my varnish drying area.

I have mixed URAC 185 in all sorts of mixture amounts and never had a problem. I don't think it requires an exact mix, as I have never found the need for it.   (Martin Jensen)

I use UF-109, which is the name of URAC-185 in Western Canada. I make the catalyst by mixing 1 part ammonium chloride crystals with 20 parts of water, by weight (you don't need very much each time but I mix enough to fill a small squeeze bottle -- enough for about 6 or 8 rods). Then I mix 1 part of that with 10 parts of glue, by weight. No heat required. The next day you can start sanding and straightening.  (Ron Grantham)

Mix 4 parts resin to 1 part AC.  I'm not real sure why some people add water, but I think it would be a very bad idea to ad any water, or even dampen your strips before glue up.  This stuff cleans up pretty easy with water and adding water to the mix would only hurt, one would think. Just mix the resin and ac up real good and go to town.  (Robert Hicks)

Regarding the water. I don't add water (I know you never said I did either) but I have read several places about dampening your splines just before gluing up. I don't know if it helps but I have done it on the last several rods with no ill affects. One of the things said, was that bamboo should have a certain  moisture content, and I hang mine in my varnish drying area for a day or so. the though is that they may be too dry for good glue adhesion. Again, I am doing it, it doesn't seem to hurt, but I would never (as you mention) add water to the mix. I'm sure this stuff is not water based. I might if it was, but  it's not. (Martin Jensen)

With regard to the water; if you are using the URAC with the walnut shell hardener provided, you do not need to add water.  What I think the original question meant to ask was, "To those of you that mix up your own catalyst from ammonium chloride, how do you go about it?"

If this is the case then you have to mix the ammonium chloride with distilled water and then to the resin.  (Robert Cristant)

Oh, the Ammonium chloride, what does that do? I don't know about that?  (Martin Jensen)

I've been using the AC solution mixed with water by weight, and then the water/ac solution mixed with resin by weight as described in some of the posts on the above page.  I've had really good results with the 5 rods that I've glued up in this manner thus far.  I tried one rod with the resin and walnut powder and felt it expanded the joint too much, but it may also have been my faulty planing.

By the way, I just finished sanding rod number 8 (the Force taper) and it is probably the best I've put out in terms of no glue lines and accuracy in the flat to flat measurements.  It's the first time I've started the taper in soaked strips.  It seemed to make my final planing go much quicker  (very little bamboo to remove) and for some reason much more accurate in terms of 60 degree angles (probably luck).  (Aaron Gaffney)

Some mostly truths about URAC (Cytec formulation). Most of the  following info was gleaned from several of the chemical engineers at Cytec  and relates to the use of pure salt crystals with no filler. Below is the spec sheet. The spec sheet relates to the walnut shell mix.

The basic ratio that the chemists recommend is 100/1, URAC/nh4cl, or  slightly less ammonium chloride, more will not set any faster and can  cause erratic bonding. This has to do with an overabundance of large  molecules clogging the process rather than expediting it. Water is not advised but as long as it is used in a ratio of less  than 10% water by weight they said it probably shouldn't cause a  problem. However they advise specific testing be done on the material  of concern (Bamboo in our case). URAC IS water based and is therefore  water soluble when unpolyermized. After it is cured (scientific  term) water will have NO effect on the bonds.  If water is used to dilute the solution you sill must maintain the  nh4cl ratio, so be aware.  All of the above ratios are by weight. Nelson Paint recommends no water be added. Cytec was not as adamant but gave me the advisory above. Zimny says for the Borden product they had advised that at least a  40% adhesive base must be maintained and it is 60% in the can.

http://www.cytec.com/pdf/URAC185.pdf

URAC®
185resin
BLT-669-A

DESCRIPTION

URAC 185 resin is a modified urea formaldehyde resin in a liquid state.  When used as an adhesive it yields craze resistant glue lines up to 0.02" thick.  It may be used for gluing wooden structures where a thin glue line cannot be obtained because of inadequate pressure on irregular surfaces.  It is an ideal “gap filling” adhesive.

ADVANTAGES

Craze resistance, low shrinkage - URAC 185 resin gives excellent bonds in glue line thicknesses up to 0.20".

Bonding temperature - URAC 185 resin may be cold or hot set at temperatures 70°F to 125°F.

Low pressure - URAC 185 resin can be used with hydraulic presses, screw-type presses or hand clamps.

Quality of bond - URAC 185 resin provides highly moisture resistant bonds meeting the performance requirements for Federal Specification MMM-A-188, Type III.

APPLICATIONS

URAC 185 resin is suitable for the following applications:  Furniture, sporting goods, millwork, joint assemblies, hollow core doors.  Decorative laminates to plywood, i.e., “Masonite” or lumber cores for dinette, sink, and counter tops.  Also steam heated automatic core machines, high frequency core gluers and heated clamp carriers.

INSTRUCTIONS FOR USE

URAC 185 resin is formulated for use by the addition of CYCAT®185 catalyst.  The hardener is a light tan powder consisting of inorganic curing agents and a ligneous filler.

In the formulation of this adhesive, the ratio of filler-to-resin has been carefully worked out.  The craze resistance and low-pressure bonding properties depend entirely upon this balanced formulation.  The thinning of URAC 185 resin with water or other resin is not recommended.

Although this adhesive can be used for some flat panel work where special considerations prevail, it is not intended for general application as a plywood adhesive.  Its appropriate application is in gluing of wooden structures where inadequate pressure or irregularity of shape of contacting surfaces make it impossible to attain uniformly thin glue lines.

In many cases, it is feasible to spread URAC 185 resin on mechanical spreaders requiring a   consistency   similar   to  conventional urea formaldehyde resin glues.  In many other applications, knife, spatula, or brush spreading are indicated; thick glue lines require an adhesive of heavier consistency to meet job requirements.  Within the limits given below, the craze-resistance and quality of bond will not be impaired by variation of consistency.

Consistency

Parts by Weight      Thin   Medium   Thick

URAC 185 resin         100      100        100

CYCAT 185 catalyst 10-13  13-16   16-18

PROCEDURE FOR MIXING

The resin may be mixed by hand in small quantities, but the use of a standard, double action mixer is strongly advised.  Add the desired quantity of URAC 185 resin to the mixer, start the agitation, and slowly add the desired weighted quantity of hardener.  Continue   the  agitation  until  a  smooth, lump-free mixture results.

WORKING LIFE

As soon as mixed, the glue is ready for application to the wood.  It is now activated and will continue to react until completely set.

If heat is to be applied to the glue line, it is often advantageous to lengthen the working life by maintaining the glue mix at a temperature of 60°F or lower.  The glue should, however, be applied to wood which is at a temperature in excess of 70°.

CYTEC INDUSTRIES INC.
Bonding & Laminating Resins
www.cytec.com
800-243-6874 (telephone orders)
203-294-5560 (fax orders)

PREPARATION OF WOOD

Wood surfaces should be reasonably smooth, free of torn fibers, and clean.  Wood for gluing with URAC 185 resin should have a moisture content of 7 percent minimum and 15 percent maximum, and the humidity in the plant should be high enough to maintain a minimum equilibrium moisture content of 7 per cent.

SPREADING URAC 185 RESIN

The glue may be spread by mechanical spreader, brush, spatula, or by any conventional type of applicator, as long as the proper mix is chosen for the method of application.  Typical spreads are similar to those used in hot or cold pressing and depending on conditions, usually range from 65 to 80 pounds for 1,000 square feet of double glue line.

PRESSING

Pressing should be accomplished to provide the minimum possible glue line thickness.  Glue lines of over .020 inch thickness are not recommended.

Pressing time depends on temperature, humidity, species of wood, and whether the assembly is stressed in clamping, or is seriously  stressed in removal from the clamps.  It is assumed that the wood is at room temperature, which is important.

AGING PERIOD

(For Structural Applications Only)

In order that cold-clamped joint-work may develop its full water resistance and full strength, assemblies should not be exposed to temperatures less than 70°F until five days have elapsed after the gluing operation.

No aging period is necessary following hot pressing to develop full water resistance and joint strength.  However, it is desirable to condition flat panels in bales for several days for optimum warp stability.

STORAGE AND STABILITY

URAC 185 resin and CYCAT 185 catalyst should be stored in their original closed containers.  Steel, enamel, paper or earthenware containers are recommended for handling small quantities in the shop.  Spreaders and brushes should be cleaned immediately after use with water at 70°F to 125°F.

Useful life of URAC 185 resin also depends upon the temperature to which it is exposed:

Temperature        Useful Life

60°F                     12 months

75°F                     6 months

90°F                     3 months

HEALTH AND SAFETY

The estimated acute oral (rat) LD50, acute dermal (rabbit) LD50 and the 4-hour inhalation (rat) LC50 values for this material are 850 mg/kg, 690 mg/kg and 3.9 mg/l respectively.  Direct contact with this material may cause moderate eye and skin irritation.  Repeated or prolonged dermal contact with this material may cause allergic skin reactions. Inhalation overexposure may cause irritation of the respiratory tract and eyes.  Before handling this material, read the corresponding  Cytec Industries Material Safety Data Sheet for safety, health and environmental data.

8/96

© 1996 Cytec Industries Inc.  All Rights Reserved.

CYTEC INDUSTRIES INC.
Bonding & Laminating Resins
Five Garret Mountain Plaza
West Paterson, NJ 07424
973-357-3100

IMPORTANT NOTICE

The information and statements herein are believed to be reliable but are not to be construed as a warranty or representation for which we assume legal responsibility or as an assumption of a duty on our part.  Users should undertake sufficient verification and testing to determine the suitability for their own particular purpose of any information, products or vendors referred to herein.  NO WARRANTY OF FITNESS FOR A PARTICULAR PURPOSE IS MADE.  Nothing herein is to be taken as permission, inducement or recommendation to practice any patented invention without a license.

TRADEMARK NOTICE

The ® indicates a Registered Trademark in the United States and the TM or * indicates a Trademark in the United States.  The mark may also be registered, the subject of an application for registration or a trademark in other countries.   (Jerry Foster)

I use URAC from Golden Witch.  I have also bought both the walnut flour and the pure salt.  But what I do is take a whole bunch (2 teaspoons) of the pure salt and grind for awhile in mortar and pestle.  I get my measured amount from that then add just a hair of walnut flour (also mortared) to stain the mix for better blend of any glue lines.  I use 16 oz. plastic cups with one as a standard to set the digital scale out to zero. Then 1../1 100 grams of resin/10 grams of water/1 gram of salt (usually half teaspoon).   I love this mix and after testing many, this is the winner.  (Geremy Hebert)

Adding water is not necessary.  10 ml of water also looks EXACTLY like 10ml of water with the Ammonium Chloride in it.  Ask me how I know.  (Chris Raine)

I had this tip about weighing on list some months ago.  (Tapani Salmi)

To all of you who use URAC:

I plan on using URAC 185 for gluing my next two rods sometime this coming week.  A couple of questions.

(1)  After reading through the archives and tips it appears that many of you use ammonium chloride as a catalyst instead of the walnut powder.  Where do you purchase the a.c.?  Will I need to order it, or is it available at a pharmacy?

(2)  It looks like the mix is 1 part a.c. to 10 parts distilled water, then 1 part catalyst to 10 parts resin.  All by weight.  Right?  I can get a good digital scale from the chemistry department at school.

(3)  If I'm not going to heat cure, how many days should I wait before removing the string and sanding the blanks?

Thanks for the help.  I used P.U. glue on my first rods and it worked well, but it was extremely sticky and a pain to clean up.  (Aaron Gaffney)

To make the catalyst I use twenty parts water to one part ammonium chloride crystals, by weight. Then a mix of 10 parts glue to one part catalyst, by weight, gives me about 20 minutes working time after I spread it on the strips. I bought my crystals at a pharmacy, but it's not a common product and they had to order it in.

No need to heat cure. The string can be removed the next day, and straightening or sanding can be done then as well.

Wash up with warm water and a bit of laundry soap.  (Ron Grantham)

You can buy ammonium chloride on eBay.   Just do a search and you'll see several listings.  Just remember 1 lb is a lifetime supply.  (Jim Brandt)

I have some a.c. I can let you have-its a couple years old, but seems to be ok for me.  Also I suggest you get some distilled water for dilution.  I can let you have some of that - I get it from our water works department which daily test water purity incorporating it with their tests.  If you want to heat treat your sticks in my oven that’s OK - decide the recipe and you can use my oven to cure  or whatever you decide. Or if you don’t want to mix a batch, I have some you can have already mixed -- a little bit goes a long way-10 percent of a couple ounce container per stick isn't much.  (Alex Wolff)

Just for fun I'm going to glue a rod this weekend with URAC.  No, I'm not at all dissatisfied with my Epon.  I just want to try something different.

Would some of you who have used the Am Chloride (that is the right name, isn't it?) as a catalyst for the glue mind recommending a mixture ratio, by volume, or by weight?  I know I have read the mixture somewhere in the past, but can't seem to remember where I read it.  (Harry Boyd)

For 100 grams of resin, mix a catalyst solution of 10 grams distilled water and .7 ( that is "point" 7) grams of ammonium chloride.  Take the catalyst solution and add to the 100 grams of resin.  Mix thoroughly for a minute or so and let stand for @ 3 minutes before spreading on to the strips.

This is usually enough to do 2 tip sections.  For a butt section I just cut the #'s in half.

I have used URAC in this fashion for approximately the last 5 years and have been very happy with the results.  (Robert Cristant)

I have test glued some strips and in one batch of URAC I use 1:10:100 with success and then for some giggles, I added another part of Ammonium Chloride, and it felt the same on the break test, if not stronger.  Anybody use 2 parts salt (?) to 10:100?  (Geremy Hebert)

I know I've said and done some dumb things and I don't know how many like or hate me, but I just glued up my four blanks last night with new URAC glue from Nelson Paint (after test batches) and I just want you guys and gals to wish me luck. I chose not to heat set, not sure it does anything detrimental to glue. Does anyone know what diff's heat set compared to long cure URAC have?  (Geremy Hebert)

We don't know you well enough to hate you!  :)

Other than cure time, there is no difference (assuming it isn't overheated).  (Larry Blan)

I'm a little confused on what catalyst to use with URAC.  From what I understand, the "factory" hardener that comes with the glue is the walnut flower.  However, seems like some believe ammonium chloride is a better catalyst for the boo.  Where is ammonium chloride available?  (Kyle Druey)

The walnut flour has Ammonium Chloride in it.  It is the catalyst, not the walnut flour.  You can get Ammonium Chloride from various sources... some Pharmacies carry it, Chemical supply houses in larger towns, or you can call Nasco in Fort Atkinson, Wisconsin and order it directly from them (they are one of many manufacturers of this stuff)  What you want is Reagent Grade, Granular, Ammonium Chloride (NH4Cl)  It is not DOT regulated, so you won't have any problem getting them to ship it to you via UPS.

Also, if I'm not mistaken, you can get it Golden witch under the name "K-6 Hardener".  You might want to call and check with Russ or Bill, but I'm 95% sure it's the same  stuff.  (Bob Nunley)

Golden Witch is where I got mine. Good luck with having the big bag of white powder shipped to you. (Just kidding).  (Bob Maulucci)

I buy ammonium chloride from my neighborhood drug store.   Its likely they won't have it in stock, but they can get it from their wholesaler by way of their next order.  I've never waited more than 10 days  to receive  my  order.  Here in  Canada I'm  paying $6.20/100 grams  or $20.00/500 grams Canadian. (approximately $4.00/$14.00 US.) retail over the counter.  100 grams is enough to do 10 or 12 rods.  (Ted Knott)

A few months ago one of our list members mentioned the use of atomized water as a prerequisite for applying URAC-185.  I came across a company called Specialty Bottle Supply that sells a 8 oz. aluminum bottle, with atomizer, CS-235, for $1.21 plus shipping.  I got mine today and it works great and considering the cost, thought the list might be interested.  They have all kinds of glass vials etc. even a hexagon glass jar. I have no financial interest.

My hand is 99.9% healed since surgery 6 weeks ago and I've started planning rods without pain.  Oh the JOY!  I had trigger finger in my planing thumb.  I plan on atomizing my next culm for glue.  (Doug Alexander)

I was digging through some old paperwork and came across a tear sheet on Melurac 450 HF and am wondering if anyone is using this right now or has in the past.  If so, I would really like to hear results.  There isn't much in the archives about it.  I remember that Bob M. was trying it out a couple of years ago, but I disappeared before the results rolled in.  (Carl DiNardo)

Good to hear from you.  I made a couple of rods with Melurac.  The first gave me no problems at all.  On the second, a rod with a 12-strip morticed butt, things got pretty sticky before I finished binding.  That was probably as much my fault as anything.   I think I still have a pound or so of the powder out in the shop somewhere.

I think Michel Lajoie in Canada was supplying it for awhile.  (Harry Boyd)

Were you using any kicker when you had your sticky situation, or was that just how it was for that go 'round.  Come to think of it, what worked so well on the first that went poorly on the second (just a timing thing with the extra pieces, I am guessing)?  (Carl DiNardo)

It might just be a cold day in H*ll, since I've ordered a batch of URAC 185.

I've always used resorcinol, since it's the best stuff out there, but a customer has strong preferences for a blond rod without purple glue lines, so I caved and am going to try URAC.

My question for you guys who use it is; do you heat set it, and if so why?  Is there any increased bond strength from heat setting with URAC?

I know I can probably do an exhaustive search thru the archives, but I've got little enough spare time as it is with little Madeline to keep entertained (she and I are "bachelors" this weekend, since mommy's going on a retreat with her girl friends). 

I wonder if 20 months old is too young to hold a block plane (or at least hold it straight)?  (Chris Obuchowski)

I do both with URAC,  sometimes heat setting and sometimes not.

My reasons for heat setting are basically to speed up the curing process so I can continue working on the rod.  I can glue, bind and heat set then let the blank cool for an hour and begin scraping and clean up.  Another reason is my garage is often quite cold and though the URAC will cure, and cure reasonably quickly, I feel better giving it some heat as the instructions are pretty clear about a 70 degrees working temperature.   However, I have slow cured sections overnight in 45 degrees temperatures without any problems thus far.

Whether there is some noticeable difference in the bond strength between heat cured and slow cured URAC I can't say, but from my experience I would say that if there is any it isn't enough to make a difference in our uses.  (Chris Carlin)

How you mix and kick the URAC should also be considered.  If you use Ammonium Chloride for example, more will make it cure quicker than less up to a point at any temperature, with the same bond strength.  (Larry Tusoni)

URAC and resorcinol are close cousins. I've used both and if resorcinol has been your glue of choice, you will find that except for color, URAC has similar working and setting characteristics. Heat set if you want, it will just kick the glue a bit faster. I do 150 degrees for a couple of hours.

I keep both resins in the fridge to extend shelf life.

You can use an ammonium chloride solution as a substitute for the catalyst powder sold with the URAC. The powder has ground walnut shells and may increase the joint space.  (Steve Weiss)

I use 140 degrees for 12 minutes.  however, the warning was to let it cure  for about 6 hours before thermal setting because the glue is too  viscous before that and may run out of the joint.  They aren't sure if it adds any strength, it just cures  faster. It is then fully cured and you can fish it the next day.  (Jerry Foster)

I would just add that although some mix by volume, I like to mix by weight -- especially if you kick it with ammonium chloride.  Just a bit off with that stuff can be a disaster.  If I remember right, there is some good stuff in the Tips site to look over for URAC.  (Carl DiNardo)

Per my many conversations with distributors and manufacturer, I'll offer the following:

Re: URAC cure times:

12  minutes @ 160 degrees
24 minutes @ 140 degrees
48 minutes @ 120 degrees
90 minutes @ 100 degrees
3 hours @ 90 degrees
4 hours @ 80 degrees
6 hours @ 70 degrees
10 hours @ 65 degrees

Theoretical working time with URAC is 2.5 hours @ 70 degrees; it was suggested to me to apply pressure within 25 minutes of application; both the glue and the cane should be at the same temperature store at 60 degrees or cooler to prolong shelf life

I've glued up 15 - 20 rods with it and had no problems at all.  (Mike Schmidt)

I stand corrected on the "working time".  When rereading my message, I thought that sounded too long, so I just checked my notes from discussions w/ CYTEC, the manufacturer, (800) 652-6013 and indeed the working times are 30 minutes @ 70 degrees; or, 20 minutes @ 80 degrees or 10 minutes @ 90 degrees.  If it's 90 in your shop, I'd turn the heat down a little.   (Mike Schmidt)

I have strips ready for glueup and a fresh can of URAC.  How warm does it have to be to use URAC? My shop (garage) is darn cold right now.  I can run the electric heater for awhile and get the temps into the 40s I think. Too cold maybe?   (Ed Miller)

If you can't everything, air, glue and strips, to 70 degrees F and keep them there until the glue cures, then don't do it now. If you had to you could keep the strips and the glue in the house for a few days, take them out to the garage and get it glued up, then back to a warm place to cure.  (John Channer)

URAC won't cure right if it's cold. You can chill it for a longer open time, but the strips should be warm and the glued sections need to be kept above 70 degrees for URAC to cure right.  (John Channer)

The URAC-185 label specifically states not to use under 65 degrees F. 

I've never had trouble between 68-72 degrees when gluing. (Bernard Elser)

I've often glued up blanks where everything - URAC, bamboo and ambient - were in the low 50s but I always heat set at 250 degree so I suppose that may cancel out the 70 degree rule.  (Chris Carlin)

Has anyone tried mixing URAC with straight ammonium chloride?  I called Nelson Paint, nice person, and she said the walnut shell mix is 13% ammonium chloride by volume or weight so it should be easy enough to measure out.   Nelson confirmed the walnut shell mix is added to help even out irregularities in wood which is not what we need with bamboo.

You would think 13% with walnut mix is still 13% without walnut mix so mixing, application and drying times should be the same.

I called Cytec, who makes URAC, several times, left messages and they haven't return calls.  My question for them was whether or not a catalyst with ammonium chloride can be made in a liquid form.  But as I think of it why bother - mix it straight up.  Can it be that easy?  (Doug Alexander)

I've used URAC for quite a few rods and have mixed it with an ammonium chloride water mix.  The recommended proportions are in the tips site.  I haven't made a rod in over a year, so I don't remember the mix off the top of my head - but you just mix the ammonium chloride with distilled water and then mix that with URAC.  I mixed up a small water bottle of ammonium chloride and water and still have 3/4 of a bottle left after several rods.  (Aaron Gaffney)

Where are you guys getting your ammonium chloride?  (Chris Obuchowski)

www.digitaltruth.com or other source via Google.  (Ted Godfrey)

You get it on the internet via credit card, where else?  (John Channer)

Look on eBay for nh4cl.. I think 1 lb was about $5.00.

The direct mix is .01 to 1. Works great, Bruce is now using it. Forget the water, at least that's what the chemists told me.    (Jerry Foster)

There was  a discussion on glues over at the Classic Fly Rod Forum a few months back and Bob Nunley said that he uses URAC with a liquid catalyzer and never gets glue lines. I think it was ammonium chloride in a liquid form. You could search for it there on the Rodmaking and repair page.  (Will Price)

URAC might be considered the pro grade of Weldwood plastic. As Tony says both are UF adhesives. The Weldwood stuff works but why would you bother when URAC is much more predictable. ( No glue lines.) Yes I have used it and it has the same result as URAC with the filler, glue lines.  (Jerry Foster)

I have been using the formula of 1 to 10, 1 part Ammonium Chloride to 10 parts water, then using 1 part solution to 10 parts URAC with good results. No apparent glue lines unlike with the walnut filler. Either I am getting more skilled with the plane or this method is producing tighter joints. Either way thinking of changing my handle from Chip Node to?  (Tim Pembroke)

What is a good mixture to use with URAC-185 if i use volume?  Oz or teaspoon/table spoon.

I do not have a scale to weigh it. (James Lafary)

This has worked for me when I was using URAC.

I have used the smallest measuring spoon in a set, I think it’s 1/8 teaspoon of ammonium chloride with 6 cc. of hot water to make a solution. I then use 2 cc. of this solution per 4 teaspoons of URAC I then heat set the sections at 150 for 1 hour. When blanks come out of the oven you can sand the string off and continue to work on them. I use a syringe to measure the liquid. This has worked out for me for quite some time.  (Joe Arguello)

I just use a plastic soup spoon. Does not matter as long as you use one standard for both parts by volume. (Gordon Koppin)

I have an issue with glue lines. When I have finish my final planing, I bind the sections to check for voids in the strips. All look good, nice and tight, however when they are glued up and bound, I am finding gaps. I am using URAC 185 in a 10/1 ratio, as it is a mid point of the recommended ratios. There is a good amount of squeeze out when the strips are bound, this happens, (the gaps) whether I remove the apex of the strips or not. The glue is fresh by the way. Any suggestions on improving the outcome??? Is there a better thinner glue that you could recommend??  (Jon Holland)

Where do the gaps show up?  Are they around the nodes?  Are there wisps of bamboo that are getting caught between the strips when binding?  (Greg Reeves)

There are those of us who wouldn’t use anything but Epon epoxy or equivalent.  But that won’t solve your problem if your triangle isn’t equilateral is places or you have tear-outs.  It will eliminate purple glue lines and gaps caused by walnut flour if you use it.   (Al Baldauski)

Are you using the Walnut catalyst?  It has lumps and will cause problems.  (Pete Van Schaack)

Yes, I am using the walnut powder, and mixing it well( I think) then again maybe not as well as I thought. (Jon Holland)

It's not the mixing, but he little chunks that are in it.

Go to the bamboo rodmaking tips site, they have formulas there to mix without it.  (Pete Van Schaack)

I would suggest you  not rub  down your strips with mineral spirits. if you use some thing use alcohol, denatured, but try not using anything. You can damage the edges of the spline which will cause a void at the edges. If it is a planing problem Wayne suggests putting a mirror at the end of the planing form so you can observe whether you are holding your plane level. If you scrape with a razor blade much, you can cause a scooping out of areas if your strip is not dead straight. If there is a rodmaker close to you maybe someone can make a more specific suggestion. (Timothy Troester)

Since I also use URAC and do not have problems with glue lines let me list some of the precautions I take.

Make sure your planing forms are flat.  You might have to file or use a sanding block to get them flat.

Make sure your planes are flat.  I placed my beat up Stanley 9 1/2 on a bench sander.

Make sure your plane blades are very sharp avoiding tear outs and eye the blade parallel to the plane.

After my strips are taped I open them and place them flat on the workbench so the apex can be lightly planed.

Use a toothbrush and clean the strips from dust.

I use an orchard mister to lightly dampen the strips with distilled water and hopefully raise any missed wisps of bamboo and brush again with a fine toothbrush.

I purchased some Ammonium Chloride on Ebay and mix without the walnut shells although I never really had a problem with the shell mix.

Make sure your glue is thoroughly spread on every bit of the strip by going back and forth using a fine toothbrush.  (Doug Alexander)

Assuming your forms are flat, your V-groove is accurate, and your plane is set up properly, here is the way I get nearly flawless results on my strips.

My plane started with a wide throat (a large gap between the blade and the slot it sits in).  I machined the plane to accept a piece which closed the throat to less than 0.06 inches.  There are planes out there that have adjustable throats.  If you can get one, set the throat as small as possible.

I start planing on previously rough milled strips.  They are as straight as I can get them, the outside rind planed flat, but no more.

I use a plane with a 0.005 deep X 0.75 wide groove in the sole.  I set my plane to take about 0.002 cuts.  I mark my strips at the butt ends to indicate where I want to finish up relative to a mark I place on my form with a sharpie.  I slide the mark on the strip two stations down from where I want to finish up. Alternate, taking five passes per side until the plane bottoms out on the form.  Now I slide the strip up ½ station and take a couple of passes till the plane bottoms out.  Flip the strip, move it up ½ station and take a couple more passes till the plane doesn’t cut anymore.  This is all possible because your blade is recessed about 0.003 above the form so you won’t cut steel.  This approach guarantees that your finish pass is parallel to the form.  You STILL have to strive to keep your plane PARALLEL to the form, though.

Now I take a custom scraper, a wood block (the block has a grooved sole as well) with a carbide scraper blade clamped to the end at a 90 degree angle to the form, and set one paper thickness above the form (0.003”). Your strip should be about 5 inches from your finished position.  Slip the strip up the form about one inch and use the scraper to take off material from the “power fiber side” until it doesn’t cut any more to make sure it’s flat and true.  Flip the strip to the next side, move up an inch and scrape again.  Alternate between the two inside faces until your scraper doesn’t cut any more and you’re just about guaranteed to have true triangles.  Again, your finish passes are parallel to the form.

A sharp plane and a narrow throat are key to eliminating tear-outs at nodes.  Finishing up with a scraper takes less material per pass and prevents the possibility of tear-outs on your final passes, and for me, gives me nearly “dead nuts” accuracy.

You will have noted that the strips finish at about 0.003 above the form.  This means  you  have  to  set  you  indicator  to  compensate. 0.003 less that your finished dimensions.  Try a test strip to ensure your dimensions are coming out where you want them.

I hope this long-winded description makes sense.  (Al Baldauski)

What I do to avoid glue lines, and I have none or almost none, is plane off the apex of the triangles inside the rod, so there is a hollow in the center. I usually take off quite a bit, slightly hollowing the rod. This gives the splines more place to nestle in a hex shape. I also 'whack' my rod, once glued up, and though this is mainly to get a nearly straight blank after gluing, this may also help the splines settling nicely in the hex shape. Whacking is something I read somewhere, quite a while ago, and means holding the freshly glued rod piece with one end on the floor, (I work a lot on the floor, avoids things dropping, for starters) and then push it down with a finger close to the ground. Do this several times, on all sides and check for straightness. It sounds maybe complicated, but if you'd see it once it's easy. This gives me more often than not, arrow straight rod sections.  (Geert Poorteman)

I don't know about anybody else, but you lost me on your "whacking process."  Could you try a more descriptive explanation?   (Roland Cote)

I take the rod section in my left hand at one end, the other end resting on the floor. With my right hand, I put some pressure on the section close to where it rests on the floor. Then I let the left end, the one up in the air go and the whole piece whacks on the floor, with the left end acting like a pivot. Its like letting it fall, but with some help of my right hand, to make it fall faster, with more force, pushing it down. Repeat on all flats or more than once on all flats and check if its straight. More often than not it produces a straight section with no need for straightening.  (Geert Poorteman)

This is some general information on the longevity and my use of URAC 185 from Nelson Paints. I purchased one quart in December 2005 and began using it January 2006. I made about 15 rods from this quart of adhesive. The URAC was refrigerated when not being used at 40-45 degrees F. The adhesive was brought out of the refrigerator and left to warm to room temperature for at least one day before being used for glue-up and then returned to the refrigerator. The glue up was done with a room temperature of about 70 degrees F and relative humidity of between 50 and 70 percent.

I have not had any failures of glued up rods that I have made during this time. There are three rods in finishing or glue up at this time; I have completely used up the original quart of URAC. I stored the URAC in a glass quart jar with metal cap with seal while refrigerated and not in the original container.  I like URAC because of ease in cleanup after the gluing process and in removing the binding string. I let my glued rods dry at room temperature for a minimum of 7 days before removing the binding string. I use the recommended mix by weight of adhesive and resin given in the Nelson Paints technical data sheets (100 grams of adhesive to 13 grams of powder). I use the walnut powder provided by Nelson Paints and have not had any problems with glue lines if the powder and adhesive are properly mixed.

I hope this is useful to this list of rodmakers if you are using URAC adhesive.  (Frank Paul)

Before I changed back to Titebond III I used URAC. First off Nelsons will sell that in pint cans, this helps in the amount you have on hand as it take less time to use up before you get a fresh batch. Like you I kept it in the refrigerator. I would take it out, get what I needed and put the can back in the refrigerator. By the time you mix it is at room temperature and ready to use. I never had a problem with set up time since it take quite a while to set up anyway, but I know you can actually chill it by putting the mixed up batch on ice while using it! So I guess if I would change anything it would be warming up all your stock before use. One more thing that I would do is heat treat the glued and bound strips at 150 deg. for 1 hour. As soon as the strips come out of the oven and sit for a while (15 - 30 mins.) you can get right back to work on the rod! (cut to length, mount ferrules. etc.) I usually try to get a rod done in a week so anything I can do to speed up the process helps. I realize most rod builders are much more patient than I am but if some of this helps, in the words of Martha Stewart: "That's a good thing!"

Oh, one more thing I used ammonium chloride to kick the URAC, but that's another issue.  (Joe Arguello)

If what you are doing works for you, I say stay with it.

I use URAC and I finished up my first quart in December.  I marked it when I received it and that was the previous November.  I stored the URAC in the refrigerator when not in use.  I would take what I need when needed and mix it with the Ammonium Chloride for a catalyst.  I didn’t bother to let the URAC get to room temperature before mixing.  After glue up I would leave the blank in the string for 24 hours or more depending on when I am able to get back to work on it.  If I needed to work on it the same day, I would heat set the blank at 220 for 20 minutes and then let cool and continue work.  I built 15 rods out of the quart and haven’t had any issues, knock on wood.   (Greg Reeves)

Thanks for your comments. I am not a professional rodmaker so speed is not my need, but consistency of results. I only make 4 or 5 rods per year, so my sharing of how I use URAC is for those folks who are new guys or part-timers, or those who might wish to use the URAC adhesive for their rod building. Thanks again for your suggestions.  (Frank Paul)

As always I only try to share what my experience has been. I only ask that if there is a tid bit of info in my posts that may be of help to anyone, please try it. I have certainly gotten more than I can possible give back by reading others posts.

And that, my friends is why this list is so helpful!   (Joe Arguello)

You don't have to subject the whole batch to warming... spoon out what you need and microwave it for 5-10 seconds.  (Jerry Foster)

I read Ray Gould's book when he was a member of this list so I Emailed him asking if he would still recommend URAC?  He replied saying he knew of rodmakers getting in trouble using other glues but that URAC had never let him down.

Well that was good enough for me and have used it on 40 plus rods with no failure.  I also keep it refrigerated.

When I set up for gluing, I take it out of the refrigerator first and whatever time it takes for me to fill a bucket of water for clean up, get the binder set up, get the strips ready etc. etc. is going to be the temperature of the glue.  I think the slightly cooler glue temperature allows more working time.  I mix up a batch for the butt, clean up and then mix a batch for both tips since I build mostly 2/2 rods.  There is no way I would chance mixing one batch of glue for 3 strips but that is just me.

I had good results using the walnut shell mix provided by Nelson but switched to straight ammonium chloride  just  because I could ... no real reason.  (Doug Alexander)

I've been using Epon and have been wondering about any difference in action resulting from using URAC. As you all know, Epon is made to flex, and, if my understanding is correct, URAC isn't. Initially, I would suppose the the URAC glue line would be stiffer, but I would repeated casting eliminate this? In the final result, does URAC produce a superior result?

Yes, I know some of you use TB 3 successfully, but for now, I would like to hear from those who have used both Epon and URAC and might be inclined to share their reasons why they have chosen one over the other.  (Wayne Kifer)

Three or four years ago I made twin rods, 7' 6" two weights.  Same culm of bamboo, same hardware, etc.  One rod was glued with URAC, the other with Epon 826 resin and a combination of 3164 and 3140 hardeners (if I remember correctly).

Both rods have long since left the shop, so I cannot tell you anything about differences in performance over time.  But as soon as the rods were finished,  I did a number of deflection tests.  The URAC glued rod deflected much less than the Epon glued rod.  I don't have the numbers in front of me, but I seem to remember that the average difference in deflection was quite dramatic.  Perhaps 20%.  (Harry Boyd)

Gee! That is significant. That would account for the difference in my Payne 98 and someone else's that seemed more limber. Did you cast both the rods and just board them?  (Timothy Troester)

I’ve measured variations in stiffness of up to 15% amongst strips from the same culm and from the same internodal space.  So some of your difference could be from that.  Another possibility is that the rod you finished first had more time to sit around and absorb moisture.  This causes the rod to swell and changes the stiffness.  Of course, maybe it was all due to the glue! Just some food for thought.  (Al Baldauski)

Well, that's exactly what I was wondering about Harry. The benefits of using Epon are obvious, but as it's made for bows, and made to flex, one has to question if it's actually the best way to go with rods. It's hard to come up with a conclusive test as any two rods made from the same culm will perform somewhat differently due to the differences in thickness of power fibers in each set of strips. But I doubt there would be 20% difference.

Another question would be, if a rod glued with Epon would have more of a tendency to take a set over time and hard use. How many of the rest of you guys have gone to URAC, or Nyatex, because of the stiffness of the glue joints?  (Wayne Kifer)

Here's a link to the set resistance test that I did with several glues.  URAC was the only glue that significantly out performed the others.  Simply put, URAC is a very hard and brittle glue when cured.  I'll try to remember to bring the test blanks to SRG this year. You can see more here.   (David Bolin)

That does tend to support what Harry thought as well. I doubt any of the top glues we use could really be considered unsuitable. What I was originally considering was the possible benefits of using a stiffer glue to tweak the action a bit on rods made from culms with less than optimum power fiber density. I, for one, can't afford to be that critical about which culms I choose to use. There is also the question of how closely one can come to duplicating the action of the original taper as developed by the masters.

I know, I know, this will be another example of overkill to some. (G) I know those who have made a good many rods with Epon as well as TB 3 and no one would question the quality of their finished results. Just a question that has been floating around in the semi-vacuum in my head.  (Wayne Kifer)

I long ago concluded that the Urea Formaldehyde glues like URAC and Weldwood plastic resin produced the fastest rods because they dried so hard. The downside is that you have to worry about shelf life, moisture content in the cane, temperature, and pot life. If you are on top of all that, fine. Resorcinol is a bit less tricky, and makes an all but indestructible bond if used correctly. Epon is what I often use, however, because of it's ease of use and forgiving nature. If you don't heat set it, it takes a while to fully cure. I once fished a rod a week after I glued it. It had a nasty tip wobble. I tried it again two weeks later, and the wobble was gone. I suppose the varnish might have contributed, too. Anyway, Bill Fink has used Epon for over 40 years, and never experienced a problem, and he uses his rods pretty hard. I don't have any reservations about using it, but let's be clear, every glue we use has an asterisk attached.

URAC - see above

Weldwood plastic resin - see above, + heat resistance is low, straighten with care.

Resorcinol - dark glue line

Epon - low heat resistance + may allow some creep in high stress applications. Great for main joints, but marginal in splices.  (Tom Smithwick)

I buy my Epon here in OZ from a firm in Sydney which specializes in industrial adhesives, and deal with a bloke who must be the most helpful technician God ever put breath into.  Quite apart from anything else, I cannot figure out why this company,  which usually deals in adhesives by the hundred liters, continues to sell Epon and other glues in pint and quart lots to hobbyists like me.  But they do.

Anyway, they told me that the final stiffness/hardness/brittleness/whatever of the Epon is very largely influenced by the hardener used.  I can never recall what the hardener I use is designated, but I think it is L390 (I'd have to walk down to my shed to check) but I opted for the non brittle version, the same as the bowmakers use, working on the theory that rods flex as much as bows in amplitude, and a damn sight more frequently, too, and that there is not much use gluing a flexible material with a non-flexible glue - not if you want it to last, and to avoid fatiguing the adhesive phase of the composite.  (Peter McKean)

I think Peter is correct here.  Leaving the creep issue aside is non-flexing glue the ideal thing to use.  Unfortunately, I cannot speak of URAC because I cannot buy it in the UK, unfortunately. I've tried other Urea Formaldehyde glues with very little success. I can only conclude for me and the test I did, it was too brittle and in most cases shattered down the glue line.  Were, as Titebond 111 has never once let me down. Just my observations.

So what is the ideal glue and does it really exist.  (Gary Nicholson)

I'd say the ideal glue is the one that works for you and/or you're most comfortable with.  (Neil Savage)

After all the discussion in many venues on using water to dissolve ammonium chloride in water for use as a hardener for URAC, I called Nelson Paint Company.  I told the tech person I talked to that I was mixing distilled water and ammonium chloride and not using the walnut flour filler with AmCl in it that they provide and asked for their thoughts on this.  I not only asked them about that, but also asked about not using a hardener at all and about REAL shelf life.  I also asked about not using hardener at all and about heat setting.  Below is the email response I got from Nelson Paint Co.  (Bob Nunley)

1.)     It is fine what they are doing is using the ammonium chloride as a concentrate and avoiding the walnut shell flour as the filler. Since they are doing fly rods with very small seams the powder just gets in the way of the seam and clumps. By avoiding the flour in the mixture they are getting more viscous smooth glue. Best to use 13% of the recommended 185-hardener mixture requirement of Ammonium Chloride to 100 parts resin. Dionized water or distilled water I cannot recommend only because the directions state do not add water to URAC 185.

2.)     You can definitely heat set the glue according to Urac directions on the veneers, it does not indicate using without hardener. I have heard of folks not using the hardener at all but we certainly cannot recommend them to not to since it requires the catalyst to cure.  The glue recommendation states 15 parts of hardener to the 100 parts of resin.

3.)     The URAC will appear a cloudy light yellow and not clear when good. However once applying it, it should dry clear if using the Ammonium chloride straight.  Store in the refrigerator and URAC should be good for a year to year and one half. The key is keeping the URAC resin cool. Heat will cure it somewhat in the can if left on a shelf in 70 to 80 degree heat and shortens the life if the product considerably.

Storage and stability chart is as follows:

40ºF 12 months to 1 1/2 years (bring to room temp for easier use put back in Refrigerator when done)

60ºF 12  months  (it believe this is a bit less more like 6 to 9 months)

70ºF   6 months

90ºF   3 months

Thanks for passing along the info.

I am brand new to this game but on my first two rods I have used just the ammonium chloride powder mixed into the resin directly.  No water.  I used 1.5% hardener to resin by weight and mixed it really well.  The numbers passed to you suggests I should use 2%  (13% of 15%) if I understand it correctly.  I will do that next time.  (Rick Hodges)

Where are you all buying the ammonium chloride powder.  Can it be ordered on-line?  (David Bolin)

Here is where I got mine.  1 lb. is about $15 and a lifetime supply for me.  (Rick Hodges)

I bought a pound on eBay for $5 shipped. I think it was a chemistry shop.  (Scott Bearden)

Reading the response from Nelson Paint Co. to your inquiry regarding use of NH4CL with URAC for rod making. I've used URAC in the traditional way for a lot of years, gluing up splines, and have always experienced a slight increase in the finished dimensions. It does seem that substituting ammonium cholide as a catalyst would give more satisfactory results. I'm uncertain though, about how to interpret the statement "Best to use 13% of the recommended 185-hardener mixture requirement of Ammonium Chloride to 100 parts resin." The recommended ratio on the container of URAC 185 is 13 parts of catalyst (powder) to 100 parts of resin, by weight.

Do you understand this to mean that the ammonium chloride is to be used in that same ratio? My poor brain is ill equipped to fathom whether to use 13% of Ammonium Chloride, or 13% of the recommended proportion of powder, of Ammonium Chloride, as a substitute for the powder. I am also constrained, living in a small rural village in upstate N.Y., with locating a source for NH4CL. Can you help? Any help/advice greatly appreciated.  (Vince Brannick)

I don't know if Bob responded to this but I will take a stab.

I have been using the powder only at a rate of 1.5% by weight, powder to resin with good results.

I think what the Nelson Paint responses say is that the recommended mix of glue to catalyst, with walnut powder, is 15%.   Also that the catalyst contains 13% NH4CL.   Using the NH4CL straight you would need 13% of 15% or 1.95%.   (Rick Hodges)

Thank you very much for your input regarding my question to Bob Nunley. He did graciously respond, and he advised that his method is to dilute 1 part of ammonium chloride with 10 parts of distilled water, and to use 1 part of that solution in a mix with 10 parts of resin, acknowledging the admonition of Nelson Paint NOT to mix water with the ammonium chloride. He also suggests that using ammonium chloride 'straight' would require a mix of 1 part of the chemical to 100 parts of resin ~ all of the above by weight.

That very closely comports with your calculations, and your interpretation of the NP directive. Working within the parameters of my balance scales, I usually mix only enough glue to accommodate one rod at a time. At a ratio of 7.5 parts (walnut) powder to 50 parts resin, and taking 13% of 7.5 would seem to provide a ratio of .98 parts Nh4Cl to 50 parts resin. Thanks again for your interest.  (Vince Brannick)

How does URAC compare to Weldwood Plastic Resin?  (Tom Key)

It's pretty much the same glue, only WPR is in dry form and you mix it with water. The only problem to WPR is that it has the walnut shell flour already in it and affects the size of the strips the same as URAC mixed with the walnut shell hardener it comes with.  (John Channer)

I am ready to glue-up some sections, and would like to use ammonium chloride straight, in lieu of the walnut 'filler'. In earlier exchanges, there were some discussions about the ratio of mix, but the folder that contained my saved technical items has 'vaporized' and I will be very grateful if anyone can jog my memory. The Nh4Cl I have is in granular form, so the assumption is that it would simply be mixed into the Urac in the same manner as the walnut dust. My problem is to know the recommended mix (by weight).  (Vince Brannick)

This came from the TIPS archives:

Been using URAC since 1988, and no failures.  Until about 2 or 3 years ago, when John Channer sold me his leftover Ammonium Chloride, I used the standard walnut shell medium/hardner and did fine with it, but like the Ammonium chloride much better.  I premix the Ammonium Chloride 1:10 with distilled water, then use this 1:10 with the resin.  Works great and gives me plenty of working time.  I do use a good set of triple beam scales and get the mix dead on.  (Al Baldauski)

So to use amm-clo you first dissolve it in distilled water, then that is mixed with the URAC? I was going to order some ammonium chloride but wasn't sure it would be a fine enough powder. If you first dissolve in water that would certainly make getting a uniform mix easier, and the size of the particles wouldn't be as critical.  (Henry Mitchell)

You're right, Henry.  Ammonium Chloride is very soluble and just about any particle size will go into a 10% solution given adequate time and stirring. The 10% solution will then mix very uniformly with the URAC.  (Al Baldauski)

I think awhile back Bob Nunley posted the answers he got from Nelson paint about this approach.  The basics are.

Normally they recommend 15% walnut powder to resin by weight.

The walnut powder hardener contains 13% ammonium chloride by weight.

If you use the ammonium chloride straight it would be in the ratio of (.15 x .13) : 1 or about 2%.

Nelson does not recommend adding water to the resin.  (Rick Hodges)

The excerpt from the TIPS site was posted by Nunley, though he didn't mention it was based on recommendations from Nelson.  (Al Baldauski)

You can mix Ammonium Chloride with water/distilled water and then mix it into the glue.  But... ammonium chloride mixed in water looks just like water....and adding 10 ml of water to the URAC 185 does NOT catalyze the glue!  Ask me how I know.

Put .5 gm of Ammonium Chloride to 50 gms. of URAC 185.  That's close to 100 to 1.

And close is good.  It has a temp/time ratio.  And thus so a catalyst/glue ratio that has some fudge factor built in.  Monday mornings at the plywood factory put this to the test, I am sure!  (Chris Raine)

I mixed up a batch of URAC last night to test.  I mixed 50 grams of URAC I put .5 grams of the kicker in 5 grams of distilled water.

I did about an 18 inch piece of bamboo scraps that I planed down to butt size dimensions.  I glued and bound them in by hand after 24 hours the strips seem good I took the string off the glue on the out side and string felt dry.  The  left over glue I put in a plastic mixing cup and it is almost as fluid as when I mixed it 24 hours later.  I then added a little more of the kicker that Nelson gave me with the URAC and glued some more short pieces.  The glue felt like it was drying as I was binding the pieces but again 4 hours later the left over in the cup is still fluid.  I guess my question is this normal?  Does this stuff only set when in contact with wood?  Or did I mix it wrong.  I will try to pry apart the bamboo tomorrow to check strength.  (Rick Barbato)

Whether that's common depends on the temperature where you mixed and sat the container with the left over glue.  My shop, heat and air in the front, pray for a breeze in the back... well, in the summer, URAC will set up almost too quickly in the back of the shop, but it can be close to 100 degrees back there in July and August.  In the winter, I can glue up in a 40 degree area of the shop and take the strips up front where it's 75 and the strips cure in 24 yours easily, but the leftover cup that I left in the 40 degree area... it may thicken slightly, but you can still pour it the next morning.

Now, I don't know what the cut off temp is to make this stuff start kicking, but it does cure SLOW at sub 70 degrees F temps.  I have, for the most part, just gotten in the habit of heat setting it and not worrying about the temp in the shop.  (Bob Nunley)

I tried something new for me on my current fly rod glue up using URAC.  I completely mixed 1 gram of powder AmCl into 5 grams of the powder filler supplied by Nelson - I did not dissolve the AmCl in distilled water. This is the correct percentage of AmCl by weight for 100 grams of resin. The rod was glued up in 65 degrees F temp with about 75% humidity.  After binding the rod was left to dry in our house at 70 degrees F and about 45% humidity for about 3 days. A small container of glue was left to sit overnight in my cool shop - a thin layer of glue was very hard in 12 hours (10 mil) and the thicker section (1/8 inch) in 24 hours. The glue as mixed in this way appears as a very pale tan and has no brown lumps. The string removal was very easy and there were no visible glue lines.  This is just my experience of trying to minimize the filler material and achieve a less viscous URAC glue for rodmaking. Just my experience.  (Frank Paul)

Thanks for posting that.  I've been using the water/Ammonium Chloride solution for many years, although Nelson will tell you "don't add water".  A few times I've mixed the Ammonium Chloride crystals right into the resin, with no walnut shell powder, and that worked as well, but the glue was a bit thicker of course.  I keep mine in the shop fridge, so it's cold and about the consistency of honey when I'm trying to mix.

From what I understand, Nelson's supplied hardener is MUCH better than it used to be.  It always worked, but 20 years ago, you had no choice but to sift it through a strainer or cheesecloth to get out the chunks of walnut shell that never made it to the powder stage.  One little "chunk" would make a tremendous glue line on what was otherwise a well planed, well fitted set of strips.  The only thing I didn't like about sifting the hardener  was that I'd end up sifting out quite a lot of the ammonium chloride with the walnut shell chucks and was putting  a "guess-timate" amount back in.  I didn't care for the guess thing.

Anyway, I'm rambling.  I have been told by other URAC users that the walnut shell medium is much better than it used to be and that sifting wasn't necessary these days.  Anyone have any thoughts on this?  (Bob Nunley)

I knew you dissolved the Ammonium Chloride in water, but I thought I would give it a try this way. I also tried to just dissolve the 1.5 grams of Ammonium Chloride in the resin and that seemed to be OK as well when it set up, but I did not glue up a rod with this mixture so I have no experience in that case.  (Frank Paul)

Since we know that the walnut powder has no effect whatsoever on the chemistry of the glue, only the consistency, why do we still even bother with it?  I just use the ammonium chloride (no water) and it works just fine.  Am I missing something here?  (Dick Green)

Well, I've been following this thread, what I did was come up with a formula that works quite well. I use ammonium chloride and mix it with water. But I really experimented with it and would put the left over glue in the mixing cup into the oven as I would heat set my glued up blanks. First off I would get a dark brown slug which was well hardened but it was cracked. So I started using less and less until I got a nice piece of glue that looks like a piece of amber! So anyway here is the formula if anyone wants to try it.

First I wanted to get a completely saturated solution of ammonium chloride liquid. So I use a syringe to measure the stuff out. 1/8 teaspoon (measured with a 1/8 teaspoon and use a razor blade to scrape the powder flat across the measuring spoon) put this in a small 2 oz portion cup. Into the powder mix 6 cc of water. This give you the solution.

Now use a measure to dip out 4 teaspoons of the URAC and use the syringe to measure 2 cc of your solution. Mix well and glue up the blanks. I would then put the blanks into the oven and heat set for 1 hr at 150 degrees.

If I was doing one section at a time I would use 2 teaspoons and 1 cc solution, and always mix up fresh solution just before gluing.

Well that's it, try it if you want, call if you want or have questions. Or you can simply say to yourself .........that guy's a quack and ignore all of this!  (Joe Arguello)

I've used the powder the last couple of rods.  I sifted and had only crystals in the strainer, so I put them back in the mix.  (Neil Savage)

I get the amount of walnut powder as per instructions; then I put the powder in a sifter. The walnut powder is finer than the ammonium chloride crystals and falls through the 'cracks' leaving the crystals; mix as per instruction, glue up, clean up and done.  Numbers good, no brown lines, all rods perfect....I'm on the 'net...what can I say. (Mark Steffens)

PS: I got this tip from Ron Barch.  Make sure the sifter is a fine one; the first time I did it with my own sifter (which was too coarse) it allowed some of the ammonium chloride crystals to pass through.  After a week, it still hadn't set up so I washed it down and reglued with pure NH4Cl.  The first rod I used with Ron's sifter and it kicked off just fine. I guess my 'Dollar Store Sifter' wasn't worth what I paid for it!

Yeah.  With Epon I don't have to sift...  ;-)  (Mark Wendt)

When I used URAC 4 or 5 years ago, I used the supplied powder. I maybe made 6-8 rods with it. All of them were consistently 10 thousandths over dimension with the powder (plus whatever I was off). I had no issues with walnut chunks.  I'm probably going to switch back to urac as soon as I'm out of Epon as it is quite a bit cheaper.  (Don Peet)

I'm getting ready to  glue up my first rod.   I will be using URAC 185.  Need to know what are the mixing ration for URAC 185, by weight or volume.  Any help will be appreciated.  (Lew Boyko)

Many use weight to mix URAC (100 grams liquid resin to 8 grams hardener) is recommended in Maurer's book. George sifted the hardener powder that comes with the URAC to remove the ammonium chloride crystals. I have found it easier to use the following volume recipe based on the weight ratio. Mix a 10% solution of ammonium chloride. It will keep for a very long time. When ready to glue a rod, I measure 5 ml of that ammonium chloride solution and mix with 35 ml of liquid resin. I use a small plastic beaker with approximate ml measurements marked on it to measure the 35 ml. The resultant glue has a very good pot life and is thinner and easy to work with. Once on the rod and through the binder, you must work fairly quickly to wipe excess off with sponge and do any straightening. Has worked well for me for a long time. Hope this helps you. Love my URAC. Another tip URAC last two to three years if kept in a refrigerator.  (Tom Whittle)

I bound up my first rod last night using Urac 185  Everything went okay. I mixed the urac 2 to 1 and applied with toothbrush.

I noticed several hours after sections had been drying in the drying bin, that the dried URAC on the sections seemed to have a sugarery feel to them.   I tried to remove the string on butt end, but no go.  It will all have to be sanded off.

Is something wrong. They have been drying now for 15 hours.  (Lew Boyko)

I am not sure what you mean by 2 to 1. I use a measure by weight of URAC 185 based on data provided by Nelson Paint. I use the walnut material and mix in a 13 to 15 grams powder to 100 grams of adhesive. I let my rods cure for about 7 days after glue up  and then remove the binding string which comes off fairly easily. After removing the string one needs to lightly sand off the remaining dried adhesive on the outside of the bamboo section. Just my experience.  (Frank Paul)

If you're using the walnut flour urac does get a sugary or grainy look to it but doesn't the can say the correct ratio is something other than 2:1? Isn't it something like 100:13 by weight?

Wipe the rod down with a wet towel after gluing to remove the extra.  This will help with removing the string.  (Jim Lowe)

I have found 100 grams resin to 8 grams hardener as described in Maurer It is also good to seal open wounds I regret to announced that I am attempting to rival Nunley for his title  (George Wood)

Yesterday I called Nelson's to order some URAC.  As has been noted on the list already, they won't have any for another month or so due to a raw materials shortage.

So I thought I'd go Epon instead and I called Miller-Stephens today to order, and was shocked that it was going to cost about $80 for the Epon and the hardener.  (In the smallest size of a quart.) 

Where does a guy get some good glue for less than an arm and a leg?  (Not Titebond III)  (Tyler Beard)

May sound like an "arm and leg" for the Epon but it amounts to $3.48 per rod and falling. Bottles not quite empty yet. And some chair re gluing out of the same bottles.  (Larry Tucker)

Try binghamprojects.com and do a search for Epon. Their small package is $13.50.  (Floyd Burkett)

For those of you who use URAC. How flexible is the cured glue that  is left over in the mixing container once you have used it?

I ask because I tried some URAC on some test wood pieces for the first time and found the glue left over in the mixing container to be somewhat rubbery in consistency after a few hours. From all the statements about URAC being close to resorcinol in terms of strength, and that it produces a stiffer rod than say Titebond 3, I was expecting more of a hard, brittle set.... or am I missing something? (Steve Dugmore)

URAC takes a full 24 hours to cure at room temp.  That is what I call a primary cure.  It will still be cream colored, and while not rubbery, it won't be rock hard.  After a few hours, especially if you have a significant amount left in the container, then it is going to be a little rubbery.  Every time I glue, I set my glue cups aside and look at them the next day.  If, in 24 hours at the 75 degrees I keep the front part of the shop, it's hard, then the section is good to go... but I don't really worry about what it's like after a "few" hours.  Cure time is 24 hours, so why worry about what it's like in a few hours.

Truth be told, I only look at those day old cups of glue to make sure I had my mix right. If it's cream colored and hard with MAYBE a little film of amber tint on top, then I know my mix was right and I'm good to go.  If I see that amber layer on top after 24 to 48 hours, I know I don't have to worry about my glue bond.

All that being said, I heat set my URAC to accelerate the curing. I don't like to wait for the normal "room temperature" curing process before I start the next step.  Part of that is my method of making rods, part of it is my OCD thing that drives me to go forward with the task at hand... Temperature and dwell times for heat settings are on the side of the can.  When URAC is completely cured, it will look like amber.  The thicker it is (as in what you have left in the cup after gluing) the longer it takes for it to turn amber.  I don't know if I follow directions or not, but after 1 hour at 150 in my oven, my URAC is completely cured.  (Bob Nunley)

I put the left over disk of URAC in the oven for a short while at 180 and it turned out more like I was expecting. Hard and  amber in color. I have now glued up the rod sections – will see how they turn out.  (Steve Dugmore)

For what it's worth I might mention that I bought a fresh can of URAC and Nelson Paint said that I would notice a longer working time.  I glued up a one piece 5'-10" blank which didn't take very long but I will say it never got sticky.  (Doug Alexander)

I noticed my last can of fresh URAC (received 2 weeks ago) was thinner than before.  I also have four tips that were glued up with the fresh glue that still have not fully cured after 8 days.

Wonder what they did?  (Scott Grady)

Oh boy.  I just got a new can in the mail a couple of days ago but haven't used it yet.  I was planning on gluing up a couple of sections this weekend.   I hope it all goes well.  (Greg Reeves)

For some reason URAC changed its formula and that was rejected by Nelson Paint.  As winter months went by URAC came up with another formula acceptable to Nelson.  I have no idea why they changed and I'm not sure what to tell you other than this one blank cured well enough that I sanded it, cleaned the blank with one coat of Epifanes thinner which dried and then rubbed on the first coat of Tru-Oil which is drying.

Rarely do I work this quickly but it seemed dry.  I will probably wait until tomorrow before applying any more coats though.

OK just for conversation sake I used flamed bamboo, applied water using an orchard mister which was dry by the time I used  URAC mixed with ammonium chloride instead of the powder that Nelson gives you.  When I mixed URAC I didn't notice it being that much thinner but did notice that the color was the same.  (Doug Alexander)

Probably decided they needed to "green" their product.  Which means, in other words, probably not as good as it used to be.  (Mark Wendt)

I've had blanks in the past where the glue took longer to dry but not with this one.  I was actually thinking that this newly glued up rod could be the exception for quick drying since I applied a second coat of Tru-Oil last night.  The first coat of Tru-Oil was dry within 26 hours of gluing, sanding and prep.   I checked the rod this morning and it's dry and ready for the third coat.

My can of URAC has the date 3-18-10 that was taped on it by Nelson.  I might also add that I have the exact same blank glued with the old batch of URAC and they "seem" to have the same feel or flex which is very unscientific since I use left over butt and tip strips to make one piece rods.

I'm not real happy when manufacturers change formulas and very possibly the history of that formula is lost but so far so good and with this one 34 hour old blank as a sample, URAC is the same or better than before.  (Doug Alexander)

Yeah, well, we'll have to wait and see how the new formula holds up I guess.  (Mark Wendt)

A question for those who have experience with URAC. Can I glue up blanks with the ambient temperature lower than is recommended for the glue BUT then heat set it immediately? Or is having the ambient temperature critical regardless.  (Steve Dugmore)

In short, yes.

I've glued up a lot of rods with URAC where the temp in my garage has been well below (40-50F) the recommended ambient temperature (70F?) and I immediately (or not, though usually within an hour or so of binding) heat-set in an oven following Nelson's recommendations.  I've never had any issues.  (Chris Carlin)

I glue up all my rods in my basement shop and the temp is roughly 65 degrees.  I just put them in my drying cabinet and let them sit for a few days without any heat.  I've never had any issues.  (Scott Bahn)

Yes you can. I glued up rods many winters where my shop heat was either marginal or nonexistent. If you heat set, then you'll have no problem with the glue curing completely, regardless of the ambient temp at glue up.  (Bob Nunley)

I have an unopened can of URAC dated../10. It has  been stored in an air conditioned space. Is it still okay to use, or does this come under the heading of 'if you have to ask....".  (Reed Guice)

Open the can and look at it. If it still has that creamy look, like whipped honey you used to buy in the grocery store, then it's fine. If it has even a slightly curdled look to it, throw it out. Sometimes, it will get an amber film on it, but that's no big deal. It's just the formaldehyde separating a little. Just stir it thoroughly and use it.

I keep mine in one of those small studio fridges in the shop and it stays good until it's gone. The current quart is one I bought in October and while it's nearly gone, it still works great. I used to buy it in Gallons and use it for up to 18 months or more without any problem, but my little fridge just won't hold a gallon can, so I went to quarts.  (Bob Nunley)

Do the URAC builders on this list use face masks, etc, etc, when gluing and/or sanding with this stuff?  (Reed Guice)

I use a mask when sanding.  (Scott Grady)

I probably should but have not when gluing; sometimes when sanding.  (Frank Paul)

Well if you're concerned about the formaldehyde then get a respirator with an organic vapor cartridge-a simple dust mask won't do anything for that. It's always good to wear a particle mask when exposed to dust.  (Larry Puckett)

Probably should, but I've glued up over 800 rods with the stuff and don't. Only thing that every bothered me was the fumes when gluing and that's cured with the tall ceiling in the back of my shop. (Bob Nunley)

I have completed my gluing stage of my first rod and used URAC. I went by the small pamphlet included with the product that stated to use a 2:1 ratio for an average consistency. As far as I could tell this seemed to work okay. Is this the ratio that others are using on their rods? I was not sure just how much to mix at a time, so I just did an amount that I thought would fill my small plastic cup and it turned out to be just a little too much. Has anyone got weights that they are using with digital scales for each section that might take a little of the guess work out for the next one?

Concerning the procedure on Deks Olje I am a little unsure if I am understanding it thoroughly. I understand that a PVC pipe or tube is used as a vessel and the rod section is soaked for a period of 8 days. Can 3 sections (butt and two tips) be soaked at once? and if so will it make a difference if the PVC tube is standing vertically or laying down horizontally and can the 3 rod sections touch each other in the PVC tube? Also after soaking are people just leaving the Deks Olje in the tube with a screw on plug to seal it or are they returning the unused portion to the original container?  (Bill Gates)

Urac is a catalyzed adhesive and is less sensitive to mix ratio than one like epoxy. I think the preferred method of measuring by Nelson and most makers is by weight. A digital mini-scale that will measure down to .01 grams is about 10 bucks on EBay. You can also get a bag of ammonium chloride for about the same amount and avoid any potential problem with walnut clumps. We shoot for a much thinner glue line than most Urac users do. I generally mix batches of 20 or so grams. Its more than I need for a two tip rod, but I don't often use more than a pint of the resin in a year. Pour any leftover out onto a plastic bag and let it air cure. It’s an easy check on your mix quality and a good indicator if you do not heat set.

I am also interested in where makers are storing their impregnating soup.  (Larry Lohkamp)

Some answers.

1. Yes soak all sections at once.
2. No it does not matter if the sections touch.
3. If you are soaking for 8 days then it won't matter much how the tube is positioned.  However, it must be apparent that laid horizontally the head will be negligible.  Vertically the head will be significant at the bottom nil at the top.  So if you want to maximize pressure, stack vertically and invert every so often.
4. After using tip it back in the tin, lasts for ages.
5. Not asked but, after removal allow to drain then wipe off the excess and leave to dry.  (Gary Marshall)

PS: you can get a quite decent finish by just wiping it on following the instructions on the tin but you won't get as much penetration.

I ordered some Urac 185 last summer when I heard it was being discontinued.  I thought I was thinking ahead, but I might have thought a bit too far ahead.  Any thoughts on how long Urac can remain in the fridge unopened before it becomes questionable? (Mike Marino)

I'm still using a can I opened probably 18 months ago. I keep it refrigerated as much as possible and test before using. When it goes bad I'm told it looks like clambered milk, but I've never had any go bad before using it up. (Harry Boyd)

Like Harry, I have not had quarts of Urac go bad before using them up when refrigerated. I always wrote the opened date on the can and kept some for more than three years after opening. Last Summer I bought four pint cans betting that those not opened would last even longer. When I first started building, I had to replace unrefrigerated Urac after about six months. Was told by a guy from Nelson that as long as the Urac looked the same color and consistency it was OK. Only testing I have done to date is leave the rest of the batch on the bench after glue up to see how it sets up. If it looks different enough to be questionable, a small test batch may give one peace of mind.  (Tom Whittle)

I was wondering if anyone has used the new Urac replacement glue from Nelson paint, and what the results were. (Larry Tusoni)

I have used it for one rod and I didn't see much difference, if any, from the URAC. Working time and mix consistency seemed about the same. The directions on the can are different in the fact that they don't call for heat treating. I used the walnut flour hardener and it seemed to have larger granules than the previous I had with the URAC so I ground it up better before I mixed. (John Smith)

I used Urac 185 per Bob Nunley's 10% solution for the first time tonight. This is what I learned:

• It is possible for an adhesive to be both sticky as hide glue and slick as snot at the same time.
• When you lay splines fresh with glue on top of 1-hour old glue it bonds instantly.
• Do not lean against the work bench with glue drizzled over the edge while talking to a visitor.
• Don't mistakenly leave your clean up towel laying on the work bench and forget it.
• When finished, wash all the way to your elbows before you sit down in a chair with wooden armrests.
• Don't drizzle glue on your shoes, walk thru bamboo curls then walk upstairs over the new carpet on the way to the bathroom. 

This is what I learned today.  (Timothy Troester)

I have had an issue with a rod I glued up with Urac.  I was attempting to impregnate it and soaked in a water based tile sealer without realizing a water base product would jeopardize the Urac bond.  Anyway, I have had some opening up along the strips at the glue joints and would like to try and salvage, I.e. delaminate, clean up and reglue it if possible.

Any suggestions as to a solvent that would eat/remove the Urac would be very much appreciated.  I tried Acetone for 6 hrs and it didn't seem to have any affect. (Lee Slikkers)

Since soaking in water has already compromised the bond, perhaps more soaking it in water would further delaminate it, till it eats away at all the URAC? (Mark Wendt)

After a long hiatus, I’ve started on three rods and would like to use URAC to glue them up.  I have a quart of it that I bought in April 2012 that I have never opened.  URAC’s shelf life can be extended by storing it in a refrigerator, which I have done since I purchased it 2 years ago.  Do you think it would still be good?

Is it worth the risk of using it or should I toss it out and buy the Unibond 800? (Tim Wilhelm)

I, too, have unopened quart cans in the fridge and I am still working with them.  I have been told that the clock doesn't "start ticking" until the seal is broken and the can opened but, as you probably know, 100 different rodmakers will yield 200 different answers.  All I can say is that I am not having any problems with mine 2 years later.... knock on wood...... (Marv Loopstra)

If it still looks good (same color as new) and is thin and consistent, it's probably OK. Probably best thing to do is glue up a short untapered test section. Make it thin enough, say .200 flat to flat, so that you can bend it by hand with a good amount of resistance to adequately test the joint. See how that goes and if there is any doubt, move on to Unibond 800, the replacement for URAC. (Chris Moore)

Guys, I’m still using stuff I bought in 2009.  And it’s good!  The rods are tight and phenomenally—I say, phenomenally—good-looking.  And strong!   STRONG!  Bullets bounce off! And the other handfull of wood-working projects where, admittedly, I’m talking about static glue joints, are fine.  Stored in fridge.  Top banged on after each use.  Dutiful prayers said to appropriate deities prior to and after each use. (Steve Yasgur)

I have been using Urac (now Unibond) with the Ammonium Chloride crystals mixed with water successfully for 6 years. This year I had a failure and couldn't figure out why. I mix by weight, follow the temp recommendations etc. But I got to thinking about the Ammonium Chloride crystals I use and whether it has a shelf life. Looking on-line I found that several sources say that the crystals have a 3 - 5-year life if stored properly. Per one source - "If stored under reasonable conditions of temperature and humidity (25°C at 50% or less humidity) the substance useful life may be three years or less."As I bought my Ammonium Chloride in 2009 - 10 I am thinking that this may be the culprit. Does anyone else have thoughts/experience on this? (Ken Weymouth)

I won't be much help, I'm afraid. I got my URAC from Nelson Paint the same time you did, bought the ammonium chloride from B&H Photo and mixed up an aqueous solution and have used both ever since with no problems of any kind. I still have almost a pint of resin left, and it looks like it did the day I opened the can. I store it in the fridge, which has produced some squinting from my wife, but she has accepted this as the price of living with a rodmaker who also fixes things around the house, sometimes with URAC(!). All I can suggest is dampening the splines before applying glue--and don't spare the glue! (Steve Yasgur)

Ammonium chloride (sal ammoniac) is moderately hygroscopic.  Simply means it will absorb water from the air easily if steps are not taken to prevent it.  It's very temperature stable, so unless you've had a fire, that's not the culprit.  When it's stored, best to keep it in the dark in moderate to low humidity and in a GLASS container either full up or with some sealing top fill (plastic wrap or such) to keep the air out.  This will often extend the life of a crystalline compound by years beyond the usual. 

http://www.sciencelab.com/msds.php?msdsId=9927431

Polymerization: Will not occur. Special Remarks on Corrosivity: Severe corrosive effect on brass and bronze. Special Remarks on Reactivity: Incompatible with lead and silver salts. It can react violently with ammonium nitrate and potassium chlorate. Also incompatible with bromine trifluoride, ammonium halides, bromine pentafluoride, alkalis and their carbonates. At fire temperature, ammonium chloride may dissociate into ammonia and hydrogen chloride.  Hygroscopic; keep container tightly closed. Corrosivity: Extremely corrosive in presence of copper. Corrosive in presence of steel, of stainless steel (304). Slightly corrosive in presence of aluminum, of stainless steel (316). Incompatibility with various substances: Reactive with oxidizing agents, acids, alkalis. Conditions of Instability: Incompatible materials, moisture. Instability Temperature: Not available.Stability: The product is stable.Section 10: Stability and Reactivity Data. (Bob Brockett)

Or if you live near a volcano.  Volcanos make this stuff by the carload every day.   #!^)  Actually, very easy to come by fresh stuff.  Try ebay.  Just look for the better packaging.  Those resealable foil bags are also very good.  Mixing into a solution the way Yaz did is also a great way to store.  100 grams to 900ml of water (top off to 1 liter if needed) = 1 liter of 10% solution.  (Bob Brockett)