Materials

Hi, I made this thread for materials that are allowed. It says in the rules that certain materials are not allowed. I may have overlooked it, but I do not recall it saying anything about carbon fiber. Does anyone that has looked over the rulebook know if carbon fiber is a legal material to be used in the robot?

It is, they removed the exotics parts list in 2004, you can use titanium, carbon fiber, etc… just as long as you dont go over the $3500 spending limit, and it is considered OK by the flow chart in the 2005 rules documents.

Thanks.
Good luck on your team’s robot.

I didnt think this was worth starting a new thread for so, im sorry if i should have.

Our team has been using lexan for several years now Mostly to mount the electronics and other small things. Since we now have a new montor, we are starting over from scratch as experience goes. We are now out of lexan, and we have been told we can not spend $560 on a 4’x4’x1/4" sheet of lexan.

My question: Is there anything that is comprable to lexan that doesnt cost this much? I cant immagine that other teams can fork out this much money for a small sheet. If your team does use lexan, where do you get ir from? We are looking for a material with similar properites (machineable, drillable, and flexible emough to use them for the tetras, for example)

thanks

Marcus

I think Home Depot may have it for less? And since they removed the exotic parts list, does that mean duct tape is allowed?

No, duct tape still fails the flowchart.

You should be careful buying polycarbonate at Home Despot, they also have sheets of acrylic which are not really up to the rigors of playing a FIRST game. A suitable and less expensive substitute to mount electronics on is a 1/4" thick sheet of high quality plywood. It is cheaper and much easier to work with than lexan if you don’t have access to nice tools.

Good Luck,

Rob

Last year we used lexan that came out of my dads old airplanes winshield… I dont remember if that actually went on our final robot, as it was kind of bent. Does lexan really cost that much? I gotta start asking how much the stuff we do costs…

You have to be carefully to support it right, but Plexiglas can and has been used on our bot for the last 4 years to mount electronics. As for the tetras thin sheet metal can be cut with tip snips if you don’t have much to work with, or just drill holes in them and zip tie them together.

You should be able to find lexan (polycarbonate) for under $200 for a 4x8x1/4 sheet. Here it is for $130

http://www.sdbodyline.com/aluninum.html

I wouldn’t use Plexiglass it shatters easily.
You can get lexan to crack, but not shatter. It is hard to even crack it. Remember it is bullet proof. Also the colder plastics are the easier they are to crack.

we use mostly Lexan(for mounting), aluminum, and plastic cutting board. Dude, I dont know why lexan is costing ya’ll so much, we get it ALOT cheaper here…One of our sponsors is a metalshop, so we we also get alot of scrap metal, which is usful for battery mounts and reinforcements and such. Oh, and zipties, zipties are great!

Actually, lexan by itself isn’t bulletproof. What they do to make it bulletproof is get really thick sheets of lexan and treat it with some special stuff, i’m not sure what it is. But overall, lexan is much better than plexiglass/acrylic. I think impossible to shatter in a competition of FIRST, but intentionally trying to shatter with hammer or large object, oh it’s possible…but waste of a good piece of lexan.