This is a direct replacement for the d shaft gear within each of the Qidi Box extruders.  In the picture of the gear box you can see the replacement in place. 

The picture of the broken gear is a result of the end of a spool going through.  The gear center did not strip and instead it just broke the gear in half.  It was printed in High Temp PLA from Polymaker.  Considering the goal was to print a drop in that would not strip out I think breaking in half against layer lines is a win.  I just recently printed them in Overture PC Professional to see if it will stand up any better. 

Print Instructions:

You need a 0.2mm nozzel to get correct detail for the teeth.

I printed with 4 top layer, 4 bottom layer, 4 walls and 90% infill

Make sure to pay attention to cooling and layer speeds as the smaller gear layer times are extremely short.

The D shaft hole in the gear is a TIGHT fit.  I have to apply some motivation in order for the gear to get on the shaft. 

Also pay attention to the finished diameter as you will most likely not have a perfect circle I was able to use files on the PC Professional ones to take the tips of the teeth off and then clean up the teeth with a triangle file.  The High Temp PLA gears were direct drop ins for me.  You may have to adjust for shrinkage or your machine and material.