Primitive Archer
Main Discussion Area => Bows => Topic started by: Arrowbuster on August 02, 2016, 08:35:46 pm
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I have been working on a bamboo backed osage bow. I'm getting close to getting done but with all this humidity, I suspect, the boo keeps letting go at the last few inches of the bow. I have been using titebond 3. Anyone got a better idea? This isn't working.
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Titebond has to have a completely flat mating surface, as in Noth pieces have to be smooth smooth smooth. I don't know that the humidity had anything to do with it, but I could be wrong. Are the surfaces smooth?
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There's always smooth on.
If you are going to re glue, I would grind the old glue off so you have a good glue surface. You may also want to try to degrease the osage with some mineral spirits or acetone right before gluing.
Just remember that titebond has lots of water, and the more humid the longer to dry, you might just need more drying time. I treat any titebond glue ups like I do sinew backing ... I give it lots of time, often weeks, to make sure that not only is the glue dry, but the bow has returned to the desired moisture content. I think you will find that if you really give your bows time to dry back out after glueing you will notice a difference.
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It had a pretty good mating surface but I won't say it was perfectly flat. The problem with cleaning it up is its still glued together on the rest of the bow. Y'all think I should try to separate? I'm scared I will tear it up if I do.
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It has to be perfectly mated and also not squeezed out. It takes longer to dry and if there is a pocket of glue it will just glaze over where there is too much and take a long time to set. Kinda like what happens when the lid is shut.
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TiteBond releases at 150deg(F) so you should be able to heat the boo backing enough to degrade the glue without damaging the boo.
Unibond is supposed to be as good as Urac was and I used Urac on a lot of backed bows with excellent results.
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Does anyone use hide glue for these? Then you'd need to groove most likely, but not matching. And moisture would be a problem..
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Does anyone use hide glue for these? Then you'd need to groove most likely, but not matching. And moisture would be a problem..
Hide glue works best with perfect flat mating surfaces. Moisture isn't a problem with collagen glues at least unless you are submerging your bow! Or staying out in rain for a long,long time. Also you put finishes on bows so that slows moisture absorbsion massively.
I would recommend you don't 'degrease' osage or any wood for that matter before glue-up. Acetone etc simply pulls more oils to the surface of the wood.
I've made hundreds of bows with TB3 and I guarantee you that with good mating surfaces you will not have a problem. The key is perfect mating surfaces. If I were going to use TB3 I prepare all surfaces by running through the drum sander with 60 grit paper. I've never had a single failure with TB3. Do a dry run pre glue up if you aren't certain that your surfaces are good enough. If you realize that you can't get surfaces perfect then switch to a different glue. As mentioned above Smooth-ON (they make many different glues!) EA40 is a very good glue with gap filling properties.