Using the Adafruit Feather case design and Fusion 360 an enclosure was created to hold a tracking tag using a Feather M0 w/ WiFi and a Wing GPS boards from Anafruit, along with a 3.7V 1200 mAh LiPo battery. The width of the case was reduced to match the 1200 mAh battery where a slide switch is located in the main housing given the battery compartment is too shallow to enclose the switch. The main housing height was increased to accommodate stacking the GPS wing on top of the Feather M0, where the lowest height headers offered by Adafruit were employed.

The Adafruit Fusion 360 design includes use of user parameters to enable changing key dimensions such as width and height. That said when reducing the box's width the sketch for the slide switch was improperly linked. The result was the retention bosses were outside of the main box, thus these features were modified.

While not fixed in the posted STLs, the opening for the USB is too small for most cables such that the USB data pins will not make contact. I struggled with Fusion 360 attempting to fix this feature but gave up and got out the knife opening up the USB feature after printing the main body.

Another issue with the Adafruit design is that lateral tolerance for the attachment features for the top and battery box is too large. Technically the snap tolerance is settable in the user parameters, but the fact the top and battery bottom slide back and forth a huge amount making the final assembly appear to be poorly designed junk. This issue was not fixed in the attached STLs, though I might go back and do battle again with Fusion 360 in an attempt to repair the overall snap feature tolerances.

Overall I found the Fusion 360 design from Adafruit welcome rather than starting from scratch, but in the end it was more frustration that it was worth.