[sgreco]

For size, you shouldn't need anything thicker than 3/8, my team used 5/16 and it is proabably what I'd recommend. A hot plate is what I would recommend for attaching them. If you need to fix them while they are on the bot I'd use heat gun. Most people say let it cool off before you put tension on, this is very good advice. Try not to stretch before it is completely cooled down, probably about 1/2 an hour to an hour. If it's in the heat of competition, get some Dust Off, and spray the belt, it should decrease the cooling time exponentially. I'd use PVC pipe for the rollers. Get some Sched 80 2 or 3 inch Diameter, and cut about a 1/8 inch groove everywhere that you want the belt to go. Then I'd take a piece of PVC whose ID is the same as the original one's OD and put two thin pieces on either side of each groove to further prevent slipping.