[R.C.]

Originally Posted by Ivan Helmrich

RC,

Here are the ODs of the gears and the tooth counts. As far as I acn tell, all of the gears in the FPs are the same regardless of color. The motor pinion may change. In the 2009 KoP I think the motor pinion had 16 teeth. The other option is 19 teeth. I don't have a 16 to measure, but the 19 tooth one measures .673" OD.

Large OD Count Small OD Count
Gear #1 2.283” 72 teeth .870” 25 teeth
Gear #2 2.510” 79 teeth .919” 19 teeth
Gear #3 2.634” 62 teeth 1.300” 12 teeth
Gear #4 3.501” 38 teeth

Hope this helps,

Ivan

Originally Posted by AdamHeard

I'm pretty sure the FP gears are .8 Mod. (Based on my recollection that stock FP pinions are 31.75 DP, aka ~32 DP. Knowing DP = 25.4/Mod you can solve and get .8 Mod)

Pitch Diameter (mm) is Mod x Toothcount.

So, for the 72T gear.

PD (mm) = 72 * .8 = 57.6 mm

PD (in) = 57.6 mm x (1 in / 25.4 mm) = 2.268 in (although I imagine it'd be more accurate to just enter the metric units into SW)

I know you already know how to get C-C distances, so that should cover it for you.

Thank you Ivan and Adam, big help there. Now I can get to CAD'ing that gearbox.

-RC