This is amazing, and a good example of the multi-material uses Nylon can give us. 
Originally shared by Emile Wim
Broke a few pinion and spur gears printed in ABS, I had no problem changing the pinion to nylon, the spur gear on the otherhand was too flexible in nylon, so I combined the two. I’ve run about 5 lipo packs through it, still holding. (gear is connected to hsp diff)
I remember hearing Nylon had a hard time binding to other plastics. How good is the bond, and would you know how well other material combinations will bond? That would be a good blog post. 
It appears in this case, the mechanical interlocking is all that is needed to keep this part working. This is a great part! Love it!
was this printed with a duel extruder, or in two parts?
@Steve_Sharp I agree with @Joseph_Chiu . You could even enhance this by encasing the ABS teeth in nylon by adding a solid ring of nylon at the top and bottom, to prevent the wheel from falling off. This of course assumes you have a dual head system, and can print the materials at the same time.
