Looking for the dimensions or CAD model of the small front motor shaft and 10-tooth pinion of the Pololu 20D 25:1 gearmotor.

Hi, I’m designing a custom gearbox for the Pololu 20D 25:1 Metal Gearmotor, 6V (#3450).

I need the dimensions or CAD model of the small front motor shaft and the 10-tooth pinion gear directly attached to it.

I am not looking for the large 4 mm D-shaped gearbox output shaft or the rear encoder shaft.

The official STEP model only shows the complete assembled gearmotor, so I cannot isolate the bare motor/pinion geometry.

Specifically, I’m looking for:

  • motor shaft diameter
  • shaft protrusion from the motor
  • 10T pinion outside diameter
  • pinion width
  • pinion position relative to the motor face
  • module/pressure angle, if known
  • preferably a STEP/CAD model

I want to reuse the original gears and build my own gearbox while keeping the 25:1 ratio.

If anyone has disassembled a 20D gearmotor and can provide measurements or a CAD model of the motor + pinion, I would really appreciate it. Thanks!

Hello.

We do not have a 3D model for the 20D motor’s pinion gear. What are you aiming to change about the gearbox design?

By the way, perhaps you are accidentally referencing another motor, but our 20D gearmotors do not use 10-tooth pinion gears.

- Patrick