These gears will replace the gears on the A&A pop-up valve assembly. Please watch the video. I do NOT recommend the printed gears for positions 4 & 5 - you should swap those positions as the gears will last longer. These will work and last for 2-3 months if you have them in all positions (based on my sample of 1 anyway) Using the 3D printed gears in the 1,2 & 3 positions will give you the most life out of your original set of 10 OEM gears.
The filament I used and the gcode is tuned for is Fiberlogy Nylon PA12 Natural. I dried it first and printed from the dryer. The 3MF I am uploading will print 8 gears and it takes advantage of sequential printing - it prints one gear at a time to minimize warping - oddly though it prints the brim for all 8 gears at one time and then goes back and prints each gear. The 3MF is for a MK3S+ - I have not yet tuned it for the MK4. I am also uploading the stl file so you can tune it for other printers. You will also notice I transposed 37 to 73. The filename should be 1237 (12T, 37T) instead it is 1273 - please forgive the confusion. I would fix it, but since the gears print so well, I figured it best to leave everything alone.
Here is what took time to tune - the brim to tooth engagement. It is easy to use the defaults, but then you spend a lot of time removing the brim from the teeth. I have this tuned to hold the gear down, but is still easy to separate in one piece for the most part. The model itself tok some tuning and playing with gear module to print just right - I finally got the diameters & tooth profiles to match. Elephant's foot on the first layer - chamfers, and printer tuning took a bit of time. This is not to brag, it is to let you know what you might need to change on your printer.
If you like the 2 piece impeller - you can find it here, along with a wrench to make changing the gear easier - https://www.printables.com/model/973923-impeller-2-piece-fits-aapentair
Video link -
The author marked this model as their own original creation.