[DeTomaso] Lexan?

[JDeRyke at aol.com]

In a message dated 12/7/10 11:19:09 AM, wdemelo at cogeco.ca writes:

> What type of plexi-glass should I use? Or should it be lexan? There will 
> be heat and vibration, of coarse, so what is the best material? I'm 
> thinking 3/8" thick? Can I drill and tap or will the vibration cause cracks 
> eventually?
> 
Heat, vibration, strong pulsations and blow-back of the witches brew the 
fuel producers now call "gasoline" may cloud and weaken plexiglas. Try 
UV-stabilized   Lexan- maybe 3/16" thick should give enough structural strength 
without weighing too much, unless you make the thing so large that it needs 
internal supports to counteract pulsations. The material can be drilled & 
tapped but I'd use an industrial glue for your chosen plastic rather than screws 
or bolts 'cause screws will cause strains that will eventually crack at one 
or more threads. Screws will also hasten solvent or UV-cracking at the 
strained areas. Glueing spreads loads over the entire joint so point-strains are 
less. Look at the way plastic aquariums are built- but an air cleaner 
doesn't need to be perfectly watertight, only dust-proof. 
Finally, you can polish the edges with 1000-grit sandpaper or a 
motor-buffer and even file-contour the stuff, then polish it so the result looks 
professional. There's also the polish used on plastic helmet visors and plastic 
headlight lenses.   Post photos when you're done. Good luck- J Deryke