Trimpot adjustment tool

This is a little add-on part to turn a precision bit screwdriver (I use [this one from Husky](http://www.homedepot.com/p/Husky-8-in-1-Philips-and-Slotted-Screwdriver-Set-74501/100074336)) into a trimmer potentiometer adjustment tool. You can [buy such tools](https://www.amazon.com/dp/B00HKJ90V4/ref=cm_sw_su_dp) cheaply, but why wait for delivery when you have a 3D printer :)

I made a first version as a complete bit to be inserted into the tool holder. It didn't work so well because the delicate plastic blade got stripped right away. I'm including that one for completeness but don't recommend it.

The second attempt was a little cap that slides onto the 2mm (in my case) flat metal screwdriver bit, and that one works great.

This part has some small walls, check the dimensioned drawing pictures to see if your printer can print its smallest features.