This is a DIY AT Switch that provides a large activation area and a customizable activation force using various springs.
Switch "throw distance" can be controlled by shortening the stem on the button (either in the model or after printing via sanding). Activation Force can be changed by adding a variety of commonly available springs (from Ace Hardware or Home Depot) or by removing the spring altogether.
3 "keyhole" mounts are available to mount the switch to a flat surface. Other mounting options include using a 1/4"-20 adapter like this one: http://www.thingiverse.com/thing:2061248
Additional mounts including the Go Pro style mount shown in the pictures are under development and will be posted as separate Things. This file will be updated when they are available.
Follow the full guide here: http://atmakers.org/2017/03/3d-printed-at-switches-mark-i/
UPDATE: I have added the F3D file for those who want to work on this.
Supports are recommended for the Jack mounting hole. Supports on the threads are optional (if your slicer supports removing them). There were no supports on the threads shown - notice there are some stray layers that will break off, but they will work themselves out when screwed into the bevel.
This prints fine in ABS and PLA, and should print in PETG (not yet tested) just fine. Mating parts of different types works fine.
This requires a small button switch attached to a 3.5mm jack. Full instructions will be posted at atmakers.org and this Thing will be updated.