is fiberglass legal to use on a first robot?

[mechanicalbrain]

Originally Posted by Veselin Kolev

Fiberglass gets its strength from the glass fibers that make it. If you drill a hole in a fiberglass box beam, the glass fibers are no longer continuous, so you compensate the beam's strength. If you want to have a continuous box beam with cuts in it, you have to get it custom woven by a company, and that is pricey. I would stick to using fiberglass welding glue, or if you must, only drill screw holes in the very ends of the beam. That way you retain as much of the beam's strenght as possible.

One thing to keep in mind with fiberglass as well as carbon fiber is the epoxy. I know heavy carbon fiber weave has a much weight to strength ratio than stainless steel but it doesn't take sharp impact well (it shatters because its brittle) and while Kevlar weave can take impacts extremely well over a series of hits the epoxy will turn to dust and the Kevlar turns back to fabric. I'm willing to bet fiberglass has a similar limitation due to the epoxy or glass (one or the other will give). Fiberglass is actually brittle (I found this out from experimentation) It can break of in chips or even form finite cracks due to minuscule air bubbles that weaken it.