Open SmartWatch Case and Strap

I first learned about the Open SmartWatch project in April of 2024. You can learn more via these links:

https://hackaday.com/2021/04/08/an-open-source-smart-watch-youd-actually-wear/
https://www.youtube.com/watch?v=VCfHogJ8zsw
https://www.youtube.com/watch?v=p-mDOIUr-rQ
https://www.kicad.org/made-with-kicad/open-smartwatch/
https://www.patreon.com/pauls_3d_things
http://open-smartwatch.github.io

I purchased a fully assembled watch from MakerFabs:

https://www.makerfabs.com/open-smartwatch.html

The watch worked right out of the box, but I then upgraded to the latest watch OS (instructions for doing this may be found on Paul's Patreon page).

The watch comes with a commercial wrist band, but the attachment pins failed repeatedly, so I downloaded the STL files from here:

http://open-smartwatch.github.io/resources/3d-files-light-edition/

and then modified them (larger clearance holes, larger hole for USB, and a new design for an integrated wrist strap).

The MakerFabs resin prints are wonderful, but, as stated in the watch description, they are fragile: disassemble and reassemble 5 times and something is likely to break.  So I printed my new design in TPU.

You can print the bottom (with strap), middle, and top out of NinjaFlex Cheetah TPU and transfer the  electronics and battery from the original MakerFab watch.

Print "OSW Case Strap Spike" in TPU to get the bottom of the case with an integral strap and button, complete.

Print "OSW Case Strap Spike Hole" and "OSW Case Spike" on a multi-material printer to get the case and strap in TPU with the spike in PLA.
 

Widened clearance holes, expanded USB cutout, added integral strap