Grainger Dayton Motor 4Z065A replacement stepped Gear

This is a Grainger Dayton stepped gear from a model 4Z065A motor.  This is an old motor, replacement motors and parts are very scarce. 

The gear was modelled from a damaged/worn gear. 

This is an 11 tooth very small gear with a bigger base gear that is a helical gear with 46 teeth. The helical gear has a 15 degree pressure angle. I learnt quite a bit about gears and CAD trying to design this.  

I had to count the number of teeth on both gears (what was left of one of them) and accurately measure and work out correct tolerances and work out the correct angle for the helical gear. and clearance for the spindle/shaft. So that it matched up with the existing drive gear that is fixed on the motor spindle. 

The original part actually consists of two parts. A 4.5mm metal spindle with a metal 11 tooth gear attached and a what seems to be nylon or dense/hard rubber helical gear with 46 teeth at 15 degree angle. 

I opted to design the part as a single print of both gears to aid strength and ease of printing. 

In order for this part to be feasible and strong enough to function a metal spindle was also required that was lathed and bonded to the new gear. 3d printed plastic was not strong enough for this aspect.

The part was originally tested printed in PLA for fitment and to get the angles/sixes corrected. Once proven to fit and rotated correctly was re-printed in PETG for greater wear resistance. May possibly be printed in Nylon too if required. 

The new part usage:

This gear motor is possibly used in many applications but this is actually from and old bowling ball resurfacing machine that wanted to be brought back into action by the pro shop owner. As a keen bowler myself and 3d print hobbyist I said would try and create a new part for it. (Replacement parts are no longer available with it being so old and any documentation is not useful for any replacement parts).  So the new part will hopefully now serve a valuable purpose and bring the machine it back into action!

The motor in view int he video has the new 3d printed gear in action.

Print settings used:

So far this gear had been printed in PLA+, & PETG. Prints very well using a standard 0.4mm nozzle. Ideally this is best printed in Nylon.

Print settings used:

Orientation: largest 46 tooth gear face on print bed

Supports: Not required

Material: PETG/Nylon (ideally)

Nozzle: 0.4mm or smaller

Layer height: 0.16mm or smaller (to aid layer adhesion strength)

Seams: Random

Infill: 50% cubic or gyroid for strength (no infill required to top small gear)

Top/bottom layers : Minimum of 6 (1.8 - 2 mm)