Originally posted by ottoman
I dont know how you would use "sheet rubber" to make donuts. you can buy donuts from many sources and you can glue them to the rims youself... I used to buy mine from http://www.rc4less.com/
WWeeelll OttOMan you asked for it.. How to make Tire Donuts from Sheets of rubber!..
Depending how wide you want your tires, fronts or rears, you get two or three of the 3 foot by 3 foot sheets of the foam and glue them together and clamp them flat on a surface to let dry. You then take an inner hole saw that is the size of your car's rims and put it inside a larger hole saw that is the size of the outside of your tires. If you get the same make of hole saws, they will have a threaded shank that lets you screw them together to form a double hole saw. Next you drill through the sheets of rubber with your double hole saw and low and behold you have fresh cut tire donuts coming out of your ears for a quarter of the cost of buying store bought donuts.
The only downfall of cutting your own donuts is that you end up with tons of black foam dust all over you and everything in the garage by the time you have cut out the donuts and trued them.
They have been cutting donuts like this since the early days of RC cars. The problem is figuring out what hardness and dinsity of foam to use for what type bite for certain track conditions.
I used to do this when I was driving 1/8th scale gas cars in the late 70's and early 80's but I forgot the stock numbers of the sheets. In one batch of tires we would end up only paying 4 to 5 bucks for a pair of tires compaired 12 to 15 bucks for 1/8th scale donuts at the track or hobby shop. When you race on a team of 4 or five guys and you race every other weekend all year long to get points for year end champoinships, you learn how to cut as many corners as you can to cut down on costs. You would be suprized what a crazed RC Junkie will do to keep his car running at as little a price as possible
. Or maybe you wouldn't be surprized.. LOL J/k'n