pic: 3D Printed Parts Contest

[Cothron Theiss]

Originally Posted by Mike Schreiber

Has anyone tried 3D printed bevel gears for a low load high speed application like an intake? We talked about this but we were too nervous about it. I don't know enough about the plastic properties to know if they'd be okay. I know you can buy nylon bevel gears, but I don't know how they hold up.

Short answer:
Yes. It works, but it isn't the BEST option.

Long answer:
This year, I prototyped a vertical extension of our horizontal roller intake after bag and tag. I made some 1/2" hex bore spiral bevel gears that transmitted power at a 1:1 ratio at a 90° angle. While the system did work, we ended up not using it due to size, placement, and vulnerability. To get the strength capabilites you need to use for just about anything, even a low torque intake, the gear tooth has to be pretty large. Also, I had to design the gears myself, just because there aren't many resources online that I could find for printed gears. Downloading the files for a gear won't give you the correct tolerances for printing. Had I already not spent some time last semester on how to design spiral bevel gears, I would have had no idea how to do it. Also, I had access to parts printed out of Ultem plastic, which is much stronger than ABS or PLA. In the end, it worked, but not as well as I would have hoped considering the time I put in it.
I would just use the bevel gear from WCP if you can, but I would also love to see somebody refine some designs for printed bevel gears.