Bamboo Tips - Tips Area
Glues - Epoxies

< Home < Tips Area < Glues < Epoxies

The Epoxy Book from System Three Resins

When I mix epoxy I use 3x3 Post-it pads. When the epoxy hardens I just peel off the pages that are stuck together and your ready for the next batch. Popsicle sticks for stirring can be purchased cheap at your arts and craft store. I usually leave the Popsicle stick on the Post-it pad to harden. This allows me to check the hardening without touching the epoxy. Plus it makes it easier to pull the pages apart later.  (Jim Harris)

For those who glue their rods with epoxy, is glue starvation a problem? Do you have to use lighter binding tension to restrict the amount of glue that gets squeezed out?  (Callum Ross)

I've never seen any problems with starvation. I slather the glue on, then bind with quite a bit of tension, though this may depend upon your binder. You needn't worry too much about the glue  that is squeezed out, as the epoxies tend to have more than enough  residual  in  the  glue  line  to  effect  the  bond.  (Martin-Darrell)

I don't think it's possible to starve a joint of epoxy using a binder unless you're using Kevlar and a binder used to wrap under sea cables. Starving joints needs a bit more force than binders can give so don't worry about it though it's easy to do when laminating using g clamps.  (Tony Young)

Epoxy is neither more nor less problematic than other glues as far as "starved" joints is concerned.  Regardless of the glue used, the best practice is always to set your binder to the minimum tension needed to bring the strips together.  If you have planed well, you will have no visible glue joints: if you have not, excessive tension on the binder will not bring better results.  (Bill Harms)

I like to use 5 minute epoxy to secure the grip, cap, filler, and hosel, just wondering if anyone has had problems with this type of quick setting epoxy?  What other glues do you use for the components and why do you prefer it?  (Kyle Druey)

I have found most quick-setting (5 minute) epoxies to be far too brittle to use on rod components. As a rule the faster the setup the weaker the bond. This is not always true, but I have yet to find a quick-setting epoxy worth using. I use a slow cure epoxy, set up time from 1-5 hours. There are many brands of slow cure epoxy including Flex Coat & Super Glue (both of these brands are readily available). I also use a polyurethane glue for rod components, especially real seats that have a larger inside bore diameter than my rod blank. The polyurethane expands to take up any gaps and provides a super strong bond that is 100% waterproof. This is also my choice of glue when repairing splintered rod sections. You do have to get the hang of this glue, if you use too much, it will expand out of gaps between components. I have found the use of a clamp, similar to a cork ring clamp, to be quite useful.  (Jeff Fultz)

I've had a problem with 5 minute epoxy in the past. I was using it to glue on my wood fillers and butt cap. I've had a few of the butt caps come off a year or so later. I now use the long setting type for the caps and have no more problems. No matter what type glue you use, be sure to rough up the inside of the cap with an abrasive, and also the end of the wood on the filler so you'll get a good bond.  (Jim Bureau)

I had the same problem as Jim in the past.  After several unused period, however, I found a good news.

It maybe true that  the faster the setup the weaker the bond, but we can make the bond stronger and keep it longer by  adding some very fine powder mixed into the  epoxy when we use it. The reason why the bond gets weak seems that the shorter setup epoxy would get thin sooner after it set up.  The mixed powder would prevent the glue to get thinner and prevent to make a gap  between the bonded materials.

I am adding a band saw dust (very fine) which comes out when I saw burls for wood fillers, or  a powder (this is sold)  which is used to fill in the gaps on wood surface (I don't know how I call it in English) into 5 or 10 minutes Epoxy to glue  Top Guide, ferrule.  Adding the dust of cork which comes out when I turn my cork handle, when I  glue grips and/or reel seat fillers. I have no problem  by  this now.  Any type of fine power is all right, flour, wood powder, etc. I put  a little less than the same amount (by size) of powder to the mixed epoxy.  (Max Satoh)

You may want to keep an eye on those epoxy glue bonds. Generally, fillers to not contribute strength to epoxy joints, if anything, they make the joint weaker. If you're using a filler for its intended purpose, like making the epoxy thicker (more thixotropic) then fillers are the way to go.  But to the best of my knowledge, the more fillers added to epoxy, the weaker the bond.  Usually, the laminating epoxies and other long curing epoxies have the least amount of filler in them, and give the strongest bond.  The hardened resin also tends to be a little more flexible than the quicker setting epoxies.  Perhaps our resident chemist, M-D could explain why faster setting epoxies are more brittle than the slower setting ones.  Anyway, back to the subject.  You really aren't making the bond or the joint any stronger by filling in the gaps.  The  hardened resin is the weakest part of any glue joint, and the joint becomes even weaker with bigger gaps and air spaces.  Adding filler on top of that to epoxy glue joints, tends to make those joints even weaker yet, since the filler contributes nothing to the strength of the joint.

The solution?

Better joints....  ;^Þ  (Mark Wendt)

Thank you for explanation.

I do not have enough knowledge about precise difference of strength of bonding. Academically you may be right.  My opinion is just a rule of thumb. But it seems to work by putting some filler in epoxy especially in such a case that blank flats and round inside wall of ferrule have a gap and in similar situations. Analogy is adding sand or small pieces of stones in cement (concrete). I have no intention to fight about this nor I am not using filler for glue when I glue strips.  (Max Satoh)

Such was not my intent.  I just wanted to make others aware that if the joint in question has the requirements of high shear or other kinds of loading, they should be careful on the use of filler in trying to make a stronger joint.  The best joint is just that, a joint that fits together with just the right amount of free space so that the glue joint isn't starved, or that the gaps are filled by glue and/or filler.  I've used epoxy for many years, on model aircraft, and now on fishing rods, and found that the joints that I made that were less than "good" usually had some kind of stress failure down the line.  I would think that there's probably more stress than we realize on some of the components we use in rod making, ferrules especially.  Concrete usually encounters a much different kind of loading than the glues we use.  Concrete is very stable in compression, but not very strong in shear.  That's why in many cases, you'll see reinforcing bar laid into the matrix to give it strength.  When you think about it, most concrete is poured to take the load from the top down.  Our rod making components usually don't see much stress in the way that concrete does.  Filler in the concrete matrix is added for different reasons than what we use filler for in our glues and epoxies.  It would be cost prohibitive to pour a concrete wall of floor without the addition of some kind of aggregate filler.  Also, the stresses concrete per square foot sees are exponentially smaller than the stresses our components see per square inch.  So it's all a matter of degree, I guess.  (Mark Wendt)

"Pure" concrete, without sand or gravel is not strong at all. It is there to bond the matrix together. Think about how brittle mortar is and it has sand in it. If you have a 1/8" thick piece of mortar, you can break it with your fingers and thumb. Try that with wood.

I worked in the cement industry for a while. That is cement, just one of the ingredients of concrete.

I am not disagreeing about what you are saying about glue filler. It is that there are inaccuracies in your analogy.   (Rich Jezioro)

That's true.  No such thing as pure "concrete".  Concrete is cement with the amalgams mixed in.  Mortar has different properties than does concrete, it is used to glue the bricks or blocks or whatever together.  Using wood as analogy is a bit inaccurate also, since wood is not the glue, but the substance you are trying to glue together.  Pure epoxy 1/8" thick can be broken between your fingers too.  The point I was trying to make is you're mixing apples and oranges when you compare the adhesives we use to concrete.  Fillers in concrete and mortars serve a purpose for a different type of stress.  Compressive stress is a whole 'nother animal than stress in shear.  (Mark Wendt)

That's right. The best glue joint is one that has just enough to bond things and not any more. The glue itself is almost always weaker than the wood or whatever in most cases even if it doesn't seem that way at first.

There is a reaction that goes on between the layers of the bonded materials at the atomic level which is not completely understood as well as the obvious mechanical bonding of the glue between the layers which I guess is best described as the glue's stiction to these materials. It's this layer that is the weak point and must be as shallow as possible to do the job properly. You want squeeze out to show there is enough glue to bond but not so much squeeze out to cause starving of the joint. In rodmaking, the pressures involved are such starvation of the joint through excessive pressure is not an issue provided all surfaces are coated before pressure is applied. Use as much pressure as you can in the case of gluing splines and the best fit you can in the case of ferrules. With ferrules it's tempting to be sloppy thinking the glue will make up for it but that is not good in the long term. Fillers being nothing more than flocking material to bulk the resin out don't aid to the bond, only to the handling because runny resin is hard to use which is why the more glue you have between the laminates or whatever the weaker the joint and why you need a good fit to work best. Epoxy is a special case again to most glues in that the fillers are not quite as detrimental as in other glues because the epoxy is quite strong when it's a blob of cured resin but it still holds true that the more glue you use to fill a gap the worse the joint. The fast setting epoxies never have the holding power of the full cure epoxies, that's true of any glue that requires a hardener. The faster the hardener makes the resin cure the weaker the glue will be. Stay away from the fast set epoxies for everything except the reel seat if you must and tip tops.  (Tony Young)

I use the same, and I like it!!  (Geert Poorteman)

I too use the 5-minute stuff because if you need to you can disassemble the handle section with a combination of patient heat and cold cycling. Most other glues are going to be  more permanent.  (Bill Walters)

Rodmaking members of my fishing club once made this experiment: A butt piece was glued up using ordinary white indoor glue, allowed to dry for a week and then, without any lacquering, submerged in water for a fortnight. Following this, force had to be used in order to make it delaminate. Since then outdoor glue of the PVA type has been invented........

For the first years of rodmaking I used white glue without any problems occurring. During this time the glue manufacturers constantly developed the glue in order to shorten the opening time. This made me convert to using PU glue years ago. Giving me more time to work the freshly glued up pieces, PU furthermore has the advantage of being able to stand up to a lot of heat when straightening - much more than PVA. Do remember to use thin surgical gloves when using PU or suffer black fingers for a fortnight.

BTW has anyone tried gluing up a rod with ordinary Araldite, Super Epoxy or whatever brand name is available? I have been told that epoxy cannot be used for gluing up rods, as the lignum in the bamboo rejects the epoxy. Comments, please?  (Carsten Jorgensen)

I think that several European builders are using  "local" epoxies, eg Araldite Standard (now Casco Strong). It is suitable for heat straightening while  some others  (fast curing and West boat epoxy) do not stand heat!   (Tapani Salmi)

There are a few UK rodbuilders using UHU plus 300 kg epoxy.

This is regular epoxy available from Supermarkets ('Morrisons' sell it for those readers that live in the UK) a with a two hour working time.

The two rod builders that I know of using it have done so for the last five years or so with no poor reports of performance.  (Paul Blakley)

I have purchased a 500 ml bottle of Evostik outdoor waterproof white wood glue, that dries clear.  This was recommended to me by a rod maker over here in the UK. Has anyone had any experiences using this type of glue in rodmaking. What was the outcome?

I have not glued up my first rod yet, am a bit unsure as to whether this glue is as good as an epoxy.  (Alistair Dunlop)

For the first few rods this adhesive will be fine and there are some rod builders who use it exclusively but the very best rod making adhesive that is readily available in small quantities is without any doubt Resorcinol. This glue does however leave a tinted glue line which is by some builders frowned upon.............

If you plan on making large numbers of rods the best adhesive is Aerolite 308 (with GBPX hardener) note I said 308 and NOT 306 which is quite useless.  (Paul Blakley)

Unfortunately, Aerolite doesn't seem to be available in the US anymore, although it can be ordered from the UK surface shipping only at some ridiculous rate.  SIGH!  (Neil Savage)

Even here Aerolite 308 is difficult to get hold of and I now know of only one supplier and he has a minimum order of £50 UK Sterling for one kilo, say 100 US$ for 2.2 lbs.  (Paul Blakley)

Luke, who is a periodic contributor uses it and has given me some to try, so I may soon be added to the list.  Once I've got the guinea pigs out of the workshop.

Supply has been difficult, apparently, so the Morrisons tip will no doubt have Luke scouring the local supermarkets.  (Robin Haywood)

Epon is a very popular epoxy used in the US for  bamboo rodmaking, by maybe as many as 50% of rodmakers, judging by the response this topic usually brings to this listserv.

I however, still use Resorcinol since it can't be beat (though I may give in to a couple of requests and build some pending rod projects with URAC).  (Chris Obuchowski)

Well, if epoxy won't stick to cane, we're using the wrong stuff to attach ferrules.

In order for a glue to be labeled "waterproof" in the US, it has to withstand boiling for several minutes (I don't remember just how many.)  Since I don't boil either my rods or my boat, I think "water resistant"  is  good  enough.   I  DO  get  my  rods  wet  when float-tubing.  I DON’T leave them immersed any longer than necessary.  (Half a minute for the last one I dropped in the lake.)  My personal opinion, FWIW, is that most any modern glue will work, so use whatever  you're comfortable with.  (Neil Savage)

I've experimented with Elmers Probond for a few rods last winter and fished them hard this year with no issues. The working time is slightly longer than URAC but not much more and held up to heat straightening with a heat gun. Recently when I went to purchase more I noticed holding the new bottle next to the old that the color had changed from a white to a light yellow/creamish color. Both have the  same label and reorder number but one listed @ 2003 Elmer's products the other @ 2005 Elmer products. That reorder number by the way is P9722 made in Canada.  (Tim Pembroke)

Indeed, this white wood glue looks quite strong when dry. Strong and a little elastic. I think I am going to use it just to see if it works. I don’t really know what kind of glue it is, white wood glue, locally made, but it looks good.  I know the chemical engineer in the factory that makes it,  I can ask what exactly it is.

I used Araldite epoxy for my last four rods, last week, and it looks OK. Nice to use, no mess. I just clean my fingers with cane shavings and then soap and that’s it. I know about the PU glue. I used it on about 30 rods or so, and every time, I have black hands for a week. Not just my fingers! I dislike using it, but it IS good! But back to the epoxy. I used it before on other rods, a couple of years ago, and it is still strong. I read a French article about rodmaking and that’s what they used also. And I always use Araldite fast curing epoxy (the one with the red caps) for my ferrules. And they stay on. An added advantage is that heating with a lighter will burn the glue and make them pop off easy. This is sometimes needed. At least in my ‘workshop’. For gluing up the rod itself I use slow curing Araldite epoxy (the blue caps), as it gives more working time. A disadvantage of Araldite as opposed to PU  (I use European brands like bison kit and recta vit), is that it leaves little gaps where with PU glue I have glue lines. They’ll probably fill up with varnish later on.

So the Araldite epoxy works fine,  give it a try!  (Geert Poorteman)

Any one interested in technical info for the recently discussed UHU endfest 300 can find a data sheet here.

I've used it for a few years with out problem (although I must say that, pretty well any popular glue will probably do the job).

One thing that I do like about the UHU is that by altering the mixing of hardener and binder you can alter the  properties of the glue flexibility/adhesion.

The process that suits me best is to glue up the blank using the standard mix and cure at 180 C for 5 minutes then clean up and glue the ferrule on with a more flexible mix and cure it at 100 C for 10 minutes. Reel fittings are glued on using the standard mix and cured at room temp (I use PVA for the cork handle) every thing else is UHU.  (Luke Bannister)

Breathing is good.  But the last couple of times I have been around epoxy, it left me feeling ill.  Does anyone from the list know which air filtration system might be the best protection?  Should you protect your eyes from fumes?  I wear protective gloves.  (Doug Alexander)

It seems some are allergic to the ingredients in epoxy formulations and some are not.  I can and have gotten epoxy up to my elbows with no adverse effects.  Apparently, sometimes, an accumulation of exposures can bring on an allergy, as well but it hasn’t gotten to me yet.  I do try to use gloves most of the time though.

If the fumes cause you some respiratory distress, then a chemical vapors/dust mask might help.  This is the king with activated charcoal in the masks so it looks gray instead of white.  The next step up is a more efficient mask which has a molded rubber seal and replaceable more efficient cartridges.  It’s more cumbersome, too.

Protecting your eyes becomes more difficult yet.  Headgear with forced (clean) air, similar to what some spray painters use would be the next step.

But if you’re that allergic to epoxy, maybe you should consider an alternate adhesive.  (Al Baldauski)

I know Tony from down under has developed a sensitivity to epoxies and wonder about some struggles I'm having.  I glued up twelve sections yesterday, three 3/2 rods, with Epon.  Today my eyes are itching like crazy and watering  enough that I find myself constantly removing my glasses and rubbing my eyes.

Wonder if epoxies might be an eye irritant?  Or could it just be that Spring is nearly here and the narcissus, quince, and bridal wreath are putting on buds and throwing pollen?  (Harry Boyd)

You know, Harry, I am pretty convinced it is the kicker (hardener) that causes the trouble with Epon.  I talked to the chemist at the place I buy my Epon here, and some time ago we changed the kicker, and the smell and the side reactions are better, though not as yet completely gone.

I am actually pretty chuffed with Titebond III.  I have done some destruction things to it involving heat and a shot hammer, and all I can say is that if any of my clients can provide a harsher environment than I can for my rods, then I certainly do NOT want to ride in their SUV's.

All glues were new once!  (Peter McKean)

I get a rash just like chicken pox that itches very badly mainly on the inside of my forearms even if they aren't actually in contact with glue and my eyes do water a bit also. I got it from literally crawling over the rotten stuff doing big laminate jobs and decking over a reasonably long period of time however.  (Tony Young)

Six of one and a half dozen of the other. I have COPD and the smallest thing can set of a bronchial attack. Wear a respirator when working with Epon, or any epoxy. Even if you can't smell it (male noses desensitize with age anyway) there are definitely fumes. They can enter your body through your eyes, nose and throat... (ears, too, I imagine??) Better safe than sorry. Epon has a low effluence rate, but there is still one there. You can never tell what will set your body off on a allergic reaction. Think of it as a hillside of poison oak on fire... you don't DARE breathe the smoke, your lungs will break out in the same poison oak reaction that your skin does. I know, I breathed the smoke... painful and deadly!  (Mike St. Clair)

Thanks for all the input guys.  I'll be sanding the excess glue away this evening, and will make sure to wear a good mask.  Hard to do really, with a beard and all.  I guess it's a shame I can't breathe out of the top of my head where there is no hair. I always wear nitrile gloves, but still manage to get the glue on my skin.  Usually I'm glad if I can keep it off my glasses and out of what little hair I have!!  (Harry Boyd)

Does anyone use of know where to purchase syringes that could be used to measure out any two part epoxy.  (Tom Peters)

Just about any place that sells rod building supplies has them. Especially if they sell flex coat products. My 2009 Anglers Workshop catalogue came  in yesterdays mail and they have them.  (Will Price)

Try your local drug store and look for an oral syringe.  They use these to give medicine to babies and small children.  Not 100% certain what sort of units they are marked off.  Could  be teaspoons.  (Tim Wilhelm)

Don't use those! They contain silicone for lubrication of the plunger and are proven to screw up epoxy finishes. That is specifically why Flexcoat markets their own syringes that are free of contaminates. One set will last you a long time. Don't clean them out after use, just put a small piece of saran wrap over the tips to keep out dust and debris.  (Scott Bearden)

I get 3cc syringes at the local feed store, they also carry a lot of veterinary supplies. Though I've heard tales about silicones, I've not had any problems with the 5 or 6 sets I've used.  Rinse them out with denatured alcohol first if you're concerned. I pay less than a buck a piece for them at the local Co-Op.  (John Channer)

Try your local pharmacy.  My local has a variety of sizes.  Fairly cheap too - use once and dispose.  (Greg Dawson)

It depends upon the state, some states allow you to buy syringes with out a prescription, others require a prescription. I have lots of once used syringes in 50 and 100 cc sizes. Looking at them, the opening of the needle is too small to push expo y through. If you want to try, let me know and I will send you a few. Maybe the end with the needle can be removed for a larger opening. I don't know, I never tried.  (Rich Jezioro)

A friend of mine that is a Vet gave me several large syringes they use on cattle and horses.

I rinsed them out with Denatured Alcohol and used them for several years with no problems.

I still use them when I have several rods to glue up at one time. For small amounts I use a Medicine cup or a plastic spoon.   (Tony Spezio)

Try to get what's called an irrigation syringe. This type has a long nozzle that's better for drawing up the resins rather than trying to  by pouring the resins into the barrels (a mess). A standard syringe has a stubby nozzle designed for attaching a needle and most needles are too fine to draw up the viscous resins. I use a pair of 50cc syringes of this type and I can do several rods and cork grips before refilling.  (Steve Weiss)

Try www.leevalley.com or www.jamestowndistributers.com  (Jim Sency)

You don't need syringes but a Rodmaker's Precision Scale.   It’s not too expensive during the present economic situation  (Tapani Salmi)

I had seen your website but forgot the simple scale. I was trying to come up with a simple way to mix smaller batches of flex coat 2 part. I have been using mixing cups with minimum graduations of 2.5 cc to make small batches, but 5cc is too much sometimes and I hate to waste! Thanks again for the reminder.  (Chuck Pickering)

Sometimes it is better to not mix too small a batch.  Seems like it is more difficult to get a good result.  (Scott Grady)

I agree with Scott.  Some brands of epoxy  are quite forgiving of mix ratios and some are fussy.  If you mix a larger batch, it helps because small  errors are a smaller percentage of the total.  (Neil Savage)

One way to mix epoxy finish is to use a tooth pick.

Stick the tooth pick into the epoxy  pull out the pick and count the drops off the  end of the stick into your mixing bowl. Use a separate pick for the hardener. So you don't contaminate.  (Gary Nicholson)

Drops of epoxies are not equal. Some years ago I noticed than in some brand (Flexcoat??) the 1:1 ratio (mass) of base/hardener was about 10:13 (or 13:10) in drops?  How I know: 10:10 drop mixture never got hard and thereafter I measured the volumes. The hardener was so much thicker. Therefore I went to mass measurements using my epoxy scale. (Tapani Salmi)

I have been doing it for a while and it works OK for me. But I warm the Flexcoat up first in warm water. Maybe that could even it out. Never had a problem were it never set.  (Gary Nicholson)

I have been on this list for the past 6 years or so and one of the  most frequently recurring issues is glue. To this point I have always used  URAC but like most others I have concerns about long term exposure.   Recently I have been helping a friend build a rod who is also a long time bow builder.  Knowing that laminated bows also require the use of glue for laminations I inquired as to the glue he uses and he informed me that he uses Smooth-On which based on my subsequent investigation is probably the number one glue used in the bow industry.   Also, to my knowledge, it is water soluble, nontoxic, waterproof and has a long open time; however, I do not know anything of its heat resistance when cured but I would think it would equal or exceed that of Titebond which has gained quite a following in the past several years.  In my mind, since a bow when shot, or even just strung, must put exponentially more stress and vibration on glued surfaces than a rod does along with its other attributes, that smooth-on would be the perfect choice for rod builders.  Now that my friends rod is close to being ready to glue up I was just wondering  if anyone  on the  list has  any experience  with Smooth-On for gluing up rods as I have never heard it  mentioned.  (Bob Mason)

Based on the mechanical properties published by Smooth-On, their epoxy is nearly equivalent to Epon 828/Epikure 3140 which is used so much in rodmaking.

1. its viscosity is very much lower than Epon
2. its tensile strength is slightly less
3. compressive yield strength is slightly higher
4. its heat deflection temperature is much lower
5. its flexural strength is about the same

Unfortunately, these data don't appear to exist for URAC.  (Al Baldauski)

I have used Smooth-On for the last eight or nine rods, it was referred to me by a rodmaker I have a lot of respect for who has used it for many years. He has ties to the bowyer community also. He's a list member, so I'll let him jump in here if he wants to further expound on the stuff.

All I can say is, I switched from URAC to Smooth-on and never looked back. The stuff has a long working time even at 80 degrees or more ambient temps in my garage, cleans up easily with isopropyl alcohol, makes for a fairly fast rod (or so it feels to me), the glue lines are tight, and it has a long shelf life. You can also buy it in pints, so if you only make a couple rods a year it's economical. I don't heat set, but you can. After 12 hours I remove the binding string, after 24 hours I can scrape/sand, EASILY.

I don't know about it being non toxic, though. After about the fourth rod I did feel like I was becoming sensitized to it, even though I wear latex gloves for all glues. Scratchy throat, itching, that sort of thing. Since then I have used a respirator and better ventilation with no further ill effects.

Also, I glued up a  two foot test section with it before actually gluing up a real rod, for practice.  After about a month or so, I sunk that piece in a tub of water for a few days, then I left it on the dash of my truck for most of a summer, along with a package of Twinkies. It survived fine just like the Twinkies, which by the way was a bet I had with a friend that there are so many preservatives and chemicals in Twinkies that they should look the same even after spending a few months in 100 to 120 degree temperatures. That damned Twinkie even smelled the same when I opened the package as one fresh off the shelf! No I didn't taste it...  (Tom Vagell)

I assume that we  are discussing  Smooth-On EA-40 adhesive? Its an interesting sounding laminating resin that may be of value. Its long shelf life is questionable. From the technical data sheet, "This product has a limited shelf life and should be used as soon as possible." That shelf life is not stated anywhere I can see. It also should not be considered to be a 'safe' product. It  (like all epoxies) are irritating to the lungs, eyes and produce skin irritation. People in the marine industry that have become sensitized to epoxies have reported debilitating effects. Like many of the other chemicals we use every day, it should be treated with respect.

I like experimenting and working outside the traditional box, but glue isn't one of my interests. I'm not sure its any easier to get Smooth-On than ordering a pint of Urac from Nelson's once a year... although I might have a different opinion if I was trying to work in a hotter environment. It is a very slow setting glue, and that could be an advantage if you are gluing dozens of rods at a time.  (Larry Lohkamp)

Yes, EA-40. I've used stuff that is two years old before I replaced it with new. I talked to the manufacturer about it, they said you can tell when it's shelf life is past, it gets harder to mix. The stuff I replaced hadn't even got to that point after two years stored at room temperature.

Like I said, I found it's not safe to use without a respirator.

I used to use URAC, I hated the stuff. Too short a working time for gluing and straightening in my environment. Since our relative humidity here in western Colorado is usually less than 25%, I learned from other makers in Colorado to mist the strips before using URAC,  because I did have one delamination. Do you have to do that where you are?  (Tom Vagell)

Saw EA-40, along with Unibond 800, in the 3Rivers Archery catalog. Figure it would work well, but thought I would ask before plunking down my $35 + S/H to try it out. (Chris Moore)

I've been using EA-40 for the past couple years and like it...used to use Epon but like this better...to me it's much easier to use. I mix 2 parts A to 1-part B, brush on, bind and hang. After 6-8 hours I scrape, re-bind and heat treat 3-4 hours at 150 F. No problems with the 10-12 rods done that way, a few of which have been worked hard. (Doug Blair)

What's the open work time for EA-40? (Don Peet)

Smooth-On lists a pot life of 2 hours at room temp. I only got nervous once in a warm garage, five sections lathered up and the string on my 2-string binder broke...perhaps my imagination but the viscosity seemed to be changing about the time I finished...around 45 minutes...otherwise have felt like there's plenty of time. (Doug Blair)

Any comments oh how stiff it is in relation to URAC/Unibond? (Chris Obuchowski)

I have no experience w/ URAC/Unibond...no observed difference between EA-40 and Epon. (Doug Blair)

I am ready to glue up this winter’s rod and I opened my Smooth-On EA-40 epoxy.  I found it was surprisingly viscous (that is thick) at 63F.  It would NOT run off a spoon.  I mixed up a test batch and it mixed well and set well by the next day.

I bought this product primarily because it is available in pints and Epon 828 is harder to find and I must buy a quart.  It differs from Epon in that it is designed to be heat cured and has a “limited” shelf life.  The EDT is in a good range 193F with heat cure.  It is reported to have a lower viscosity than Epon, but the data sheet just says “Mixed Viscosity, Light-paste”.  Not very informative.

The test batch self level nicely so it should be OK once I get it spread out.  Wayne Cattanach recommends heat the mix a little with a heat gun.  I haven’t tried that yet.

Has anyone had issue with this product in rodmaking? (Lynn West)

I have used EA-40 for at least ten years. I've also used product as old as 2 years with no problem. I always do test strips and break them just to be safe. I don't heat cure, waiting overnight to unbind strips is OK with me. The white hardener can get a little thick, I just nuke it in microwave a couple seconds to make it easier to mix. Sometimes I don't even bother with that, it just takes a few more minutes to dissolve. I also throw in a couple capfuls of 98% Iso alcohol to thin it a little which makes it easier to spread on strips.  (Tom Vagell)

Thanks for all the help.  I decided to go ahead.  I discovered that the unexpected higher viscosity was not an issue.  When I check can label, I found a word that I had to look up; “Thixotropic”.  I mean that the viscosity will reduce when the material is shaken of stirred.  Sure enough, when I started mixing, it thinned out just fine.  Just in case I created a small oven for that mounted on the tip of my heat gun.  It is simply a 1- 1/4” EMT coupling with the four set screws removed.  As I said, it slides on to the heat gun and the 1 oz plastic “medicine’ cup just fits in the top.  Enough air escapes from the set screw holes that it won’t blow a full cup out.  It turned out that I did not need it.

The EA-40 spread well and even with a tooth brush and easily squeezed out excess when I closed the segments for binding. 

It went ahead a glued up last weekend.  Removed the binding thread the next day and I am heat curing in a heat gun oven at 150F for 4 hours today.

Per several suggestions, I am storing the EA-40 in the refrigerator. (Lynn West)

I'm working on a blank right now that I've decided to use epoxy on, instead of the polyurethane I've used in the past. When I used poly I just squeezed and spread. I'm not sure what volume I used. How much epoxy do you guys usually mix before you start spreading it? (Bill Walters)

I am assuming that you will be using Epon. The amount of course depends on the section that you are gluing. On tips I use 2 grams of each of the epoxy and hardener, on mids and butts 3 to 5 grams of each. You will find out by trial and error. The glue has such a long working time that if you run out of glue there is plenty of time to mix some more.  (Alex Vardanis)

I use 4 tsp of resin and 4 tsp of hardener for a two tip rod.  I always have a little left over, but that is better than coming up short. (Doug Hojem)