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One of the guitars I'm currently working on has a very resinous set of sides. I've been doing some glue testing...

I glued (TB1) some lining to a scrap from the same set, let it dry for a couple hours, peeled right off.

The next test is underway. This time I've sanded the piece down and wiped it down several times with acetone and a clean paper towel.

Anybody else got any ideas?

Cheers..! It's cocktail hour! Well almost.. M

My first thought is to ask whether you took compressed air and blew out the dust before trying to glue. Skip the solvents as they only bring more resin to the surface. Sand the joint clean again and try gluing it.

If your sides are freshly baked, scrape clean in the glue region and try again. If still flat, use a high angle plane and glue to the fresh surface. Best if the linings are clean too! TB1 will stick pretty well to just about any fresh, clean wood surface (including problematic EIR) and I'd use it in preference to many other glues.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

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I agree with the other replies. There should not be a problem provided the surface is freshly sanded or scrapped and the dust is wiped clean. That being said, I really like fish glue or hot hide glue when working with oily and resinous woods. These glues will will stick to a lot of things that TB1 will not, including glass. I've used fish glue a lot on Cocobolo which is about as resinous as anything else out there. I personally use fish glue/hot hide glue for 95% of all gluing operation on my builds.

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Josh House

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Josh

I've been using fish glue for my bindings thanks to a recommendation from Steve Denvir. I really like it for that. My only issue is cure time. I know this depends on the operation but how long are you waiting before handeling?

Michael

Dry time can is a draw back with fish glue. 6-8 hours generally is what I wait, again like you said that depends on the operation. Usually I have enough stuff on the go that it isn't a problem for me to let it sit, but it sometimes takes some extra planing.

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Josh House

Canadian Luthier Supply
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House Guitars - Custom Built Acoustic Instruments.
http://www.houseguitars.com

I am coming across this with my current EIR build. I could not get it to stick to the end blocks. I ended up saying screw it and using Epoxy, worked great.

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-Marcus
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As far as PVA glues are concerned the most common reasons for bond failure involving oily woods are: Inadequate surface prep and failure to increase clamping time. Acetone is the best option for surface prep, and while some people recommend a single wipe I like to load it up and wipe it off thoroughly several times to remove as much of the surface oils as possible. I've worked with exceptionally oily pieces of rosewood and cocobolo that required about four cleanings until the rags stopped coming up with color. From a standpoint of surface chemistry, you are clearing away oils to expose cellulose that is needed by the PVA to create surface interactions and form a bond. Clamping time must be increased because the wood is still much less porous than a non-oily species, and will therefore impede the movement of moisture out of the joint. For stressed joints, I have seen clamp times as high as 72 hours. Generally speaking 24 hours is safe, but more will never be harmful.

Depending on what you are gluing, introducing heat will drive off moisture more rapidly. As long as the piece is clamped well, and the wood is relatively thin it is perfectly fine to use a heat source ranging from an iron to a hairdryer or heat gun. There is absolutely nothing wrong with heating it up 250° to 300°F and letting it bake for half an hour. It's a poor-man's version of using a hot press.