It's not UV resistive and becomes brittle. Use PMMA (Plexiglas) instead. Use superglue.
I recently finished an Elsinore ULD build using a combination of 24mm and 18mm bamboo plywood exterior and BB plywood internal bracing. I had little problem working with the bamboo plywood using carbide blades and router bits, in fact had more trouble with tear out, chipping on the BB than the bamboo. Glueing with Titebond 3 went well. My first time working with bamboo plywood so took extra care, particularily in routing, and would not hesitate in using the same approach given availability of bamboo plywood (which in my case on the east coast of the US is challenging).
I cannot imagine trying to work with polymer sheet materials and getting a decent bond with wood/bamboo. Delrin, for instance does not glue well even to itself. Plexiglass/Acrylic will bond together using a solvent that melts the surfaces. I would use mechanical fasteners, I.e., tapped holes with machine screws, which really complicates speaker construction. Epoxy might work, but you need to research the recommended formulation, and shear strength is not that great compared with the raw material.
David
I cannot imagine trying to work with polymer sheet materials and getting a decent bond with wood/bamboo. Delrin, for instance does not glue well even to itself. Plexiglass/Acrylic will bond together using a solvent that melts the surfaces. I would use mechanical fasteners, I.e., tapped holes with machine screws, which really complicates speaker construction. Epoxy might work, but you need to research the recommended formulation, and shear strength is not that great compared with the raw material.
David
No, Lexan is polycarbonate. MAKROLON and LEXAN are trademarks but are the same.
Bamboo causes a lot more wear on router bits, sawblades, chisels etc. On carbide blades you probably don't notice it that quickly except it causing more tear but in your case it's more likely it's the 'normal' tear. If you use it as a cutting board, your knifes become dull noticable faster.
You can also join it by using heat/melting, it's a thermoplastic, after all. It's not great to use, I'd reather use acetone etc to dissolve it instead of heat to join boards. A heat gun is great though to bend it. Mechanical fasteners are indeed the best option for DIY since it doesn't affect the surface and you don't have to remove the 'welding seams'.
What would happen if I use 20mm for exterior and 20mm for the bracing? Any drawbacks? Since I don't have enough 20mm bamboo board, therefore, I'm thinking about using 20mm bamboo plywood for vertical bracing, and using 15mm bamboo board for the horizontal bracing, any thoughts?
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I'm curious why polycarbonate not as good as the acrylic (PMMA) for internal bracing? As far as I know the stock unit is putting some blu-tak between the bracing and drive unit. So I assume the bracing must have some effects to the sound due to the drive units are coupled to it other than the front panel.
I cannot answer that for you. I have only used wood, plywood, K3 and MDF for brace material and corner blocking.
I don't really see how the material used as such, is very important.
Material and sealant compatibility is much more important.
I also have to wonder why one might want to incorporate materials that are much more expensive and difficult to incorporate, to perform a rather menial task.
Please help explain this for those who don't quite get it.
scraps of the same species as the enclosure
That's perfectly fine, no drawback since it doesn't have much lateral force on it (the air moves around it) and the stiffness lengthwise is practically the same.
I'm not an expert, but what I can say is that experimenting techniques and materials is the first step to discover a new way to do even a humble job and then to get a new knowledge.
It will also be expensive in terms of money and energy and time and you will have to accept some failures, but if you don't dare you'll never know.
The beautiful thing is that then the discovery of bold one can easily become a wealth of knowledge for anyone.
Because you can't glue it.
Blu tack is a very weak glue. The reason it is used there is because it stays elastic and dampens vibrations. Usually alubutyl or similar is used for that but that softens/dissolves the polymer.
Thank you for the link. I was aware of it but in practice you can't use any of it because it will be visible, affects the surface, needs near perfect conditions or would take weeks to cure before the enclosure will be finished because you can only glue 2 parts at once (epoxy) and have to wait for 72h before the next.
I found a website actually discussed about how to glue the Delrin to wood.
https://talk.dallasmakerspace.org/t/glue-suggestion-delrin-to-wood/52544/3
Sounds like it is possible.
Here's another trick for gluing plastics that are normally difficult to bond...
https://en.wikipedia.org/wiki/Flame_treatment
https://en.wikipedia.org/wiki/Flame_treatment