Reproducing tiny plastic gears for vintage 'gear'

[Jeff_Birt]

These are pictures of the ALPS Y-axis (paper feed) 3D printed gears I have been working on. The image with the black mark on two teeth is a gear that broke after about 800 printing minutes (V9). The teeth are holding up just fine which was my initial worry, one of the spring perches broke on this gear. These break often on the original gears as well. You can see it broke right at the top of the chamfer that I added to strengthen it. There is another picture of a new V9 gear so you can see what it should look like.

The other picture is a V10 gear which has a chamfer that runs top to bottom. The base of the perch is now about 1.8x as wide as the top. The continuous chamfer prevents the concentration of stress where the V9 perch broke.

The 4th picture is the inner gear, the side closest to the printer's build plate. On a resin printer this is the side that has a lower quality (less detail) than the side away from the build plate. The number '10' embossed into the plastic is 1mm tall and 0.1mm deep. I did this originally just to see if the printer could resolve this fine detail on the build plate side. With just the right resin, with the part at the correct angle to the build plate, etc. it does a good job. Amazing results on a $300 printer.