Summary

Replacement gears for a Roomba 581. But it should fit lot's of other models, too.

Instructions

I finally designed all gears because I found out that none of my original gears were in perfect shape anymore. The OpenSCAD file gives you the opportunity to tweak some design parameters.
Keep in mind that 2 of the gears need an metal axle of about 7 mm length and 3 mm diameter. I glued them inside with a drop of super glue. The code is of poor quality. Just a mashup of two libraries and some new lines of code. You should be able to tweak some parameters if necessary.

I recommend to use something else than PLA as material for the small motor gear. During longer operation the motor heats up. When it reaches the glass temperature of PLA the axis begins to slip and the gear wores out. Maybe one gets better results with Nylon or HIPS. The other gears are still in a good shape. Even after longer operation.

Used code from following things
http://www.thingiverse.com/thing:268787
http://www.thingiverse.com/thing:6021
Many thanks to their creators.

Roomba 581 gear