I was driving down the road the other day and something red caught my eye, it was an abandoned little red car sitting under a pile of trash waiting to be picked up by the garbage truck only a mile behind me.

I continued to travel down the road a bit then thought that I might be able to fix it for a friend of mine to play with. I did a U-turn and took the pile of trash off to get a better look.
The steering wheel was missing as were the batteries, but it had all four wheels and the motors were still in place. I decided that if I couldn't fix it that I could always return it to the trash for the next pick up date.

Since it was a Friday night some of my friends came over to work on their projects with me. I stripped the little car down to the bare chassis and connected 12 volts to the motors to test them out. One motor made a very slight attempt to turn, the other seemed frozen. 
We decided that the motors probably would never work again but we would try a little more power. Being a bit insane... I decided that my MIG welder would work on it's lowest setting... it was after all just a jumbo sized 16 volt power supply.  ( Right? )

The motors did turn that time, the gears made a grinding sound and they vibrated very badly. We knew the motors were not ever going to work right again. Well... there was nothing else to do... I set the MIG welder to 100 AMP mode and hit the switch. It sounded like somebody fired up the Batmobile... the wheels spun nearly 80 miles an hour and looked really kool with all the smoke and flames pouring out of the holes.
Soon the motors glowed red and then gave up in a glorious and quite festive display of lights, fire, and smoke. We stripped the motors off the chassis after the fire went out and they cooled off a bit. ( Grin )

Here you can see the stripped down chassis. We decided that even though the car couldn't be fixed up for a ride-on toy with ease... it would make a wonderful platform for a new robot base.

This car is great... it has a nice metal frame which makes it lightweight and very strong. The area in the rear seems to be perfect for batteries.
I designed a set of sliding blocks to be mounted on the front frame. Another block is mounted to the wheel cross-arm to form the basis of a screw driven steering system. 

By moving the block left to right, I can make the wheels turn. I can adjust the tension on the block to adjust the amount of slippage allowed so that it should be able to run very smoothly.