Gluing a layer of Plastic between wood?

[woodfab]

I'm starting a new guitar build and was thinking of gluing up scraps of mahogany with 1/8" strips of maple between them, then thought  "could I use  Clear Poly-cast instead of maple?"

Has anybody done this? What type of glue would I use?

How would a neck be with three pieces of mahogany and two pieces of 1/8" clear poly-cast between them? And maybe through the body also.

A'm I looking for trouble?

   

[curtisa]

Epoxy would be my guess. PVA wouldn't adhere to the plastic. CA might work but would be more expensive by volume, plus I wouldn't want to be exposed to the fumes while trying to glue it all together for any length of time.

I'd be a bit concerned about the potential for wood movement due to climatic changes. Plastic won't move at all due to changes in temperature, humidity etc, whereas wood can do. That could lead to strange warps or twists in the neck as the two materials fight each other, or worst case the glue join(s) between the two materials fracturing. Maybe save it for the body only?

Interesting visual idea though  Shine some LEDs up the length of it and it would be pretty striking in the dark.

[Bizman62]

6 hours ago, woodfab said:

How would a neck be with three pieces of mahogany and two pieces of 1/8" clear poly-cast between them? And maybe through the body also.

Technically that would be similar to using carbon fibre rods, most likely adding stiffness quite a lot. A bunch of 0.5 mm veneers would act pretty similarly as glue is basically liquid plastic which more or less impregnates veneers that thin.

Visually that's an interesting idea and if lit, even more interesting as @curtisa said.

But he also mentioned wood movement which is a concern I share.

[henrim]

To be able to glue plastic you should know what plastic is in question. Different plastics need different glues. Many of them don’t like to be glued at all.

With right solvent you can melt the surface of plastic and when pressed against wood it finds its way to the pores. When cured it forms a pretty solid bond. I don’t know if it would be solid enough for neck. Maybe. 

For epoxy there is not much on plastic to stick to. You can obviously help that bond by grooving or perforating the plastic.

Like mentioned above, wood and plastic have different thermal etc. characteristics so gluing them together may not be ideal. At least not in structural use where the joint is under stress. A mechanical bond would possibly be more stable.

If I was going to try this I would perforate the plastic strip and laminate with epoxy.

[woodfab]

Maybe I'l  glue up some test pieces and see what happens.

[Bizman62]

Test pieces are a must when experimenting!

For testing purposes I'd also try to speed up the aging process. UV light and heat are commonly used for that in laboratories when trying to figure out a longevity prognose. A month outside under the Californian summer sun would tell you everything you need to know, North of Boston you'll have to improvise.