Yes spigor, the OD is approx. Ø27mm. It's the cut of the tooth that's wrong. Even with my gauge pins (Ø2.1mm) being way bigger than you recommend, on the 'bad' gear, the pin fits all the way down into the root of the tooth. On the good gear (it's mating pair) the pin is sitting on the tooth...
Hmm, not sure how to take that mfgenggear.
However, I sense your reluctance to offer a complete picture of the answer here...nothing for free, right? I get it.
Perhaps you'd be at least willing to confirm or deny if a Ø.083" pin would be suitable for measuring over the wires on the above...
I've made this gear before with these specs (10+yrs ago), but with a new vendor I'm having to explain how to check it and I'll be darned if I remember. It's way undercut but it's mating gear they did right.
The spec is:
Spur Gear
1.0 Module
20° Pressure Angle
.001" of backlash
Hobbed on a...
