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< Home < Tips Area < Glues < Nodeless I use Epon on blanks and I'm about to try my first nodeless rod. Reading through the archives, it seems that most experienced nodeless makers like Chris Bogart use Titebond II for the splices. What are the motivations for that? Is it mainly ease of use? Would I have a problem (aside from mess and time) if I used Epon for the splices and blank glue-up? (Jerry Madigan) Titebond II is easy to use, grabs quickly, cleans-up easily and isn't very toxic. Disadvantages are its perceived intolerance of heat, and lower strength than some other glues. Quite a number of splices (54?) have to be made to construct the strips for a nodeless rod. Unless you have a large number of clamps, I use three small Pony spring clamps for each splice, you will end up mixing many batches of glue. Al Medved and others use inexpensive spring binder clamps, which makes it more feasible to have a large number of clamps, perhaps rendering the mixing issue moot. I have not had good success keeping the joints aligned when clamping with them. I align the scarf joints by placing them enamel side down on a plate of glass, then apply the middle clamp, turn the joint over, straighten it if necessary, and apply the clamps on either side. Because of the weight of clamps and the manipulations that I go through, I don't like to have more than one joint clamped on a strip at a time, which necessitates distributing the gluing sessions out over time. Titebond II makes this easy. If I used resorcinol, my regular glue for sections, much mixing would be required. (Bill Lamberson) Is this the Titebond II water based wood glue? I recently tried Titebond II Extend wood glue and loved it. No more URAC. (Marty DeSapio) Last night I was getting ready to ferrule my first nodeless rod and after flexing the tips sections, I noticed that both tips retained the bend/set. I flexed the tip in the opposite direction and again the set was retained but in the opposite direction. I guess I'm somewhat puzzled but this situation. I glued the rod using TiteBond II for the splices and Epon for gluing the strips together. I can't recall what ratio I mixed the Epon it was what most people recommended (from a previous question posted to the list). The heat treating of the nodeless culm sections was done at 350 degrees for 15 minutes and was done by Chris Bogart, so I have to believe that wasn't the problem. Any suggestions? I hate to waste the time finishing the rod if it is going to set so easy. Other than the rod taking the a set, it looks great. This was my first experience with nodeless, Titebond II and Epon, prior to this I've always done noded rods with URAC and never had such a problem. (Bob Williams) Has the Epon completely set yet? It can take a few days depending on the mix ratio and conditions. (Tony Young) Sounds to me that the Epon didn't cure. (Don Schneider) That is what I think too. I had Epon left in the mixing container for several days and it is not totally set up. Can the Epon be heat set when using TB 2. I heat set at 180 F. Don't know enough about the Tight Bond and what it will do at that temp.. I plan on making my first nodeless so this will be information for me also. (Tony Spezio) It can behave strangely sometimes. The same ratio will cure hard a rock one day and do as you mention the next. The people who developed it do recommend post heating though it's not a requirement. From the little I've seen of post heating by others this does seem to be a sure fire way to cure it as expected though as Bob has written it's been post heated and the rod still takes a set. Anybody remember what was thought the last time this came up? Did AJ mention this occasionally happening for no apparent reason and putting it down to a natural material not co operating? (Tony Young) This message thread looks like heading down the 'mix ratio' road again. When using epoxies, there is absolutely no choice whatsoever in the mix ratio. You MUST use the manufacturers recommendation, otherwise you have too much resin or too much hardener which will remain unreacted and act as a plasticizer at best. Epoxy hardener reacts with a specific quantity of resin- no more, and no less, ever, no exceptions, final, that’s it! If you aren't getting the cure time, setup time or whatever with the resin/hardener you have at the manufacturers recommended ratio, you have to change products to get the result you want, sometimes you can change the grade of hardener and still use the same resin. You just can not fiddle with the ratio of resin and hardener. In other systems, like Urea Formaldehyde, Melamine Formaldehyde, and polyester, the hardener is a catalyst for the reaction, and you can vary the amount within limits. In these cases, the catalyst speeds up the polymerization without becoming an important intrinsic part of the polymer. In epoxies, part A molecules join on to the end of the molecules of part B. If you have too many of one or other left over at the end you have a stuff up. (Dave Kennedy) Shell Epon will work with a 2:1 resin:hardener or 1:1 (Tony Young) Epon products (at least the ones we use) do indeed have a wide ratio of resin to curing agent mixability. So do the U-40 products. David is correct, though, about the reactive qualities, and one mole of anything will only react with one mole of something else. Anything not reacted is just hanging around. Epon 828 and Epi-cure 3140 have an optimum mixing ratio of 100:50 or 100:45, depending upon which piece of product literature you read. This ratio is determined by weight, not by volume. One can guesstimate using the "by volume" method IF previous weights have been converted into the volume equivalents BUT you are taking a chance. While hit and miss may work in a lot of things in life, chemistry isn't one of them. Mixing at the recommended 100:50 or :45 ratio, 828 and 3140 have some rather extreme properties. Upping the curing agent ratio to 100 parts will not make the bond stronger, in fact it makes the resultant cured product more flexible, and not as strong (which David pointed out). Strength here is relative, and I have no idea at what point we've crossed the threshold for our rodmaking. Proper mixing is as important as anything when dealing with epoxies. I mix for a full two minutes, then allow the mixed product a dwell time of five minutes before using it. This allows the reaction a good head start. Why do I do this? Because it is the recommended procedure, and guess what? I don't have the problems so many others seem to have. SO, it's a crapshoot. You rolls the dice, and you takes your chances. Some times you win, sometimes you lose. Nothing ventured nothing gained. That's all the cheesy adages I can think of at the moment. Basically, if you depart from product specifications and recommendations, don't be surprised when you have problems. (Martin-Darrell) Epoxies can be weird to work with though even when you're sure it's done right. I know I shouldn't say that but it's true of course if it doesn't work right when the same batch does most of the time you've obviously done something wrong, you just can't think of what it was and incorrect ratio tending towards too much hardener is normally the cause in my experience. The less lee way you have in the mix ratio the more chance you have of messing up. If you're using small amounts I aim for a 2:1 with Epon I've found there are less problems. I always warm the two mixes a little if they are treacle like to they pour better and measure the hardener first so I can adjust with the resin intentionally aiming for something a little less than twice the hardener so it falls somewhere between 1:1 and 2:1 resin:hardener. Mix very well, the longer the better and be careful you don't apply any not mixed improperly that may be around the sides of the container your using to mix it all in. For very small amounts I mix it on a piece of paper sort of like mixing colors of paint on a palate. When I was involved in boat building the place I worked for had a rule of the minimum amount of glue you should mix because the larger volume mixed the less potential for error. We used a 2:1 glue and used paddles to scoop the glue from the canisters. One paddle was twice the width of the other with a line marking the high tide mark making getting the right ratio pretty easy even for first year apprentices thought they took some time to learn not to use the wrong (used) paddle in a canister, we used so much glue it this mixing of resin and hardener in the canisters was usually OK during the week but having a large amount of a 20kg canister of epoxy cure over the week end because of that was always good for a laugh on Monday morning. (Tony Young) Well, I don't know. This leaves me a little confused. In a spec. sheet available through Miller-Stephenson for their Epon resin 828 and Epi-cure hardener 8140, tests were reported using a range of mix ratios and curing processes. Evidently, the highest sheer strength came from a mix-ratio close to 2-1 (resin-to catalyst), whereas their recommended mix-ratio is 1-1. This leads me to believe that nearly anything in between is going to be OK. (Bill Harms) |