Page 52 of Boston Gears Gear Catalogue ( a 3.2M file) (
http://www.bostongear.com/pdf/catalo...rs_catalog.pdf) indicates that the H1212R gear that came with the robot kit has the following specs:
H1212R
-pressure angle 14.4 deg.
-helix angle 45deg
-12 transverse diametral pitch
-pitch diam 1"
-Right hand gear (the H1212L is a Left hand gear)
If you plan to mate this gear with another one, you need to use a 12 pitch gear also, with Right hand teeth. If the pitch diameter is larger than 2" (the diameter of the mating H1224R gear that we got), then you will need to modify the plastic gearbox housing accordingly. I posted a note elsewhere on this board on how to do this.