Summary

130mm RC ABS (work in PLA too) printed Buldozer
with servo motor and gears
laptop batteries
7805 voltage regulator
"all functions" each thread and the arm.

Note : printing in ABS made it easy to assemble with solvent.

Instructions

ERRATUM : i was using ABS at that time, beveling it to be PLA. so for ABS use acetone to glue parts together.
For PLA use iron solder ;)

It's an RC buldozer that i designed and made with an huxley reprap.
To make it you need :
-2x 608 bearings,
-M8 screw rod with some nuts (nylon nuts seems to fit well inside 608 bearings)

some tiny screws and washers
3 servo "9gr" and two have to be modified to become "motors" (unlink the potentiometer from the last gears and cut the block that prevent it to make complete turns)
a battery pack (mine is 2 elements 3.7V 2200mAH from a laptop battery)
And some voltage regulator to amke 5V for the receptor.

Now for the mechanical part :
Before printing make sur that you correctly positioned the part in your slicing software, some of my stl are "in the air"
You will certainly need some wood fill mainly on the tank thread and the tooth of the "wheels" to make them run smoothly.

I use "acetone " (french word for the chemical that melt the PLA) to glue all the parts together

The thread are assembled with paper clip

Don't forget to screw the servo before assembling and to not glue the hood and top to put batteries and electronic in it.

If you have a programmable transmitter you could make mix and have on one stick all directions.

By the way the thread are slipery on hard surface but on grass/earth/sand it should be fine.

Oh and i forgot : it's really fun to drive and clean the mess on my desk with it ;)

See it in action :
http://www.youtube.com/watch?v=zUUmX01zgo0

ps : thread inspire by http://www.thingiverse.com/thing:10924

RC printed Buldozer