? on a vacuum form project

[dragon23]

i want to vacuum form a guiter body and i was wonder what thickness i should use to do it with

[chan luci]

6 mm thick

[spektr]

I wouldnt think of using 6 mm just yet. There are many questions to ask... such as the tone quality of thermoplastics in general.... Think for a minute.... Many manufacturers of guitars for the mass market have the wherewithall to vaccuum form the bodies if it worked well. To the best of my knowlege, nobody does.
Guitars are basically "air pumps". The guitar takes string energy, transmits it thru the bridge to the top of the guitar. Those vibrations resonate in the body and exit thru the sound hole. It is very important to get the correct mix of materials to convert string energy to sound. Using a thermoformable plastic with its acoustic dampening properties looks to be a poor idea. I know for an absolute certianty, that Titebond 2 glue, by itself, can dramatically deaden the acoustics of an otherwise well done wood guitar. I personally cant concieve of petg working.
Structurally, the body of the guitar must mate to the guitar neck and resist the pull of string tension. Petg exhibits creep, that is a very difficult property to overcome thru design alone...
If you decide to do this, my best of luck to you, i just don't see it working for the reasons i've covered as well as a few others of lesser importance, like, how do you glue it together, and how do you make a traditional dovetail joint work to attach the neck?

ALSO to Luci Chan......
PLEASE explain to me why 6 mm is a good choice, if you are sitting there knowing the manufacturing processes for guitars AND you know something I don't, speak up so we can all get smarter, otherwise, it might be best to not comment unless the facts can be shown to support your position.. We need new guys to be successful, so instead of shooting short answers lets look hard at whats going on below the surface.

This is a great question for the builders at the Musical Instrument Makers Forum. www.mimf.com

Thanks..

Scott

[chan luci]

Hi Scott,
I understand you have good knowledge on guitar. But your 'advice' for me to make you and other listeners smart is not really what was asked for. Read the question out there. Did the questioner ask for explanation of guitar manufacturing? No. He simply shot a single objective question.

Assuming the guy knows the material and guitar like a smart guy like you., and not to waste time I gave a short reply suggesting 6 mm. Well, why 6 mm and if done with 6 mm, my choice is Lexan, this should give better results for all to see whether be it strength, acoustics and all.

The better answer is if the poser asks me to make guitars I can. But making the whole world smarter is not my job and the more you talk, less you work. So pls do not be sarcastic or take advisory roles, as this would not augment members participate in such forums.
Thanks
Chan Lucie

[cod]

I have to admit that 6mm sounds a little arbitrary. But I also am intruiged by the prospects of vacuforming a guitar body-never thought of that!. It wont be easy. Lots of trial and error. The neck joint will be tough. I would think that petg would not be a great choice- or acrylic -- but on the other hand, damping isn't necessarily a bad thing..... for instance if you were making a hollow body bass it might make a desirable sound- probably not so much for a guitar- but it depends on what you are going for..... I would try multiple plys of polycarbonate myself.

[spektr]

Chan... First, My appologys for getting your name incorrectly in my last post. Unintentional on my part. Second, yes, he asked a very short specific question. So you are correct as far as not making anybody smarter. I'm sure you can build a guitar out of 6 mm petg, I can too. It wont be a very good one, but then That isnt your concern. Youre right, less talk more work. We shouldnt help others prevent failures caused by their inability to form questions correctly. We should just answer exactly what was asked, and never seek the reason the question was asked......... Perform exactly to the spec and press on.................... Scott.