Outside of the box..

[Ice Mike]

I was reading the "alternative lam suppliers" thread, and I posted a random thought asking if there were any plastic alternatives to fiberglass for clear backings...In the process of doing a little thinking on the subject, I had another random thought and, in the spirit of not hijacking the other thread, started this one to pose this question..

Has anyone ever tried taking a sheet of plexiglass and running it through their lam grinding setup to make clear backing glass?

[TX FLY CASTER]

Not sure epoxy bonds well with polycarbonate.

[H1tman7]

About the only way to glue Plexi or acrylic is with a solvent that actually welds the pieces together. Cant imagine any way to get it to stick to wood or other materials.  Plexi will also take a set.

[LittleBen]

I've heard of phenolic as a belly material but that the closest thing I've heard. Plus plastic tends to melt when sanded so I think it'd be technically challenging just to produce the lam.

[Ice Mike]

Very good points guys. What about pvc? Not sure that I've ever seen clear pvc, but it does seem to play well with adhesives.

Please pardon my ignorance if these statements or questions are stupid... My expertise lies in programming, not chemistry, however with the increasing difficulty in finding quality clear glass laminations, it may be time to start trying to consider the ridiculous right?

[LittleBen]

Mike although I agree that streaks in glass may be a problem. It's a relatively small problem, and an intermittent cosmetic one at at. In he long run it's probably cheapest to just buy a lot of glass and sort it carefully.

Anyway regarding the PVC:
PVC as it's typically produced is not going to be clear. It's mainly amorphic with very limited %chrystallinity, basically the PVC chains are randomly arranged in the material like spaghetti, not arranged in a pattern like ramen noodle blocks.

Amorphous polymers are generally opaque, and crystalline ones generally clear.

Please understand this is a massive generalization and many materials are somewhere in between the two.

But on the other hand, lots of people have made PVC bows.


If I had to choose a polymer to make a backing material it would almost certainly be UHMWPE. The same stuff high performance string material is made from. It's used for tons of stuff, we'll understood processing technologies exist, and it's ridiculously strong. Is it clear? Maybe if you have fibers of it imbedded in more plastic like the way glass lams are made.

Cheers.

[JamesV]

Mike...........

If you did get a bow built using plexiglass it would fail under the stress. I have experimented with a lot of different materials, plexiglass and formica as laminates  and they all failed. The solution I found for streaky, cloudy glass is: I don't build bows with clear glass. Black or brown, your choice.

James

[Ice Mike]

Thanks for the responses guys. Just trying to throw some thoughts around. I knew there have been other people that have had these same thoughts and have seen them through to conclusion, and that there is a reason why we do things the way we do. I guess I throw out these random thoughts because is rather learn from your experience than from my own mistakes. I have found that I can go a lot further a lot quicker if I just listen to the guys that have been there.

Anyways. Thanks again.

[KenH]

Clear PVC is available, I know PVC bowyers who have used it.  But PVC does not play well with wood, adhesively...