There are a lot of people who converted a RC tank to a robot chassis. One thing which I absolutely not like about this solution that it’s not really “robot design”. I love thinking a lot about how to build a chassis/make several parts for the robot.
The second thing which I do not like is that you will always see that this was a RC tank. (tracks)
The third thing is the spare tracks. You will probably not find a track for this anywhere. So as soon as your track dies, you will run into a problem.
One possible solution is building a tank base from scratch, which I am doing currently in my (limited) free time. Alu, plexi, 2 cordless drills, 2 bike chains, 2 PVC pipes, screws, creativity and you are on the right track.
You can follow my progress on my blog, which is listed below. Note that my spare time is limited at the moment, so there might be less updates the next 3 weeks, add me on twitter to get updates.\
If you need help just ask.