A week ago the ancient electric pencil sharpener died. The motor could be heard spinning when  a pencil was inserted, but no sharpening action. I took it apart to find the large gear that drives the sharpening mechanism was broken in two pieces. As I shook it out, it broke again. Time for a new unit? Not with a 3D Printer! Before I gave up on this item, I would try and print a replacement gear.

Designing gears is not fun, but the on-line CAD program Tinkercad had a community supplied gear builder. I took measurements from the broken gear, counted the teeth (70) and designed a new one. My first print wasn’t correct. The broken gear did not reveal the drive slot was only partially into the gear, with a round shaft for the rest. Once I had one new gear with the slot all through it was easy to see what needed to be done. The next gear fit well and worked. It’s noisy, but it works.

The next challenge was designing an optical connector for my underwater camera housing. The very expensive part from the manufacturer (double any equivalent price) screws onto an optical fitting on the housing. The bare cable has an optical end, but must be mechanically connected to the strobe and housing. On the strobe it’s a simple hole, but I needed something similar on the housing. Again using Tinkercad, I was able to design a simple connector. It took a few tries to get the sizes correct as things must be tight but still fit. After 5 tries I had a good fit. Now to take it to the water for a test dive.  The optical port is shown mounted on the housing on the upper center left.