About this 3D model

This thing was made with Tinkercad. Edit it online https://tinkercad.com/things/iQQgeBA2LVT Corner clips for Printrbot Plus with heated bed and glass. Short enough to clear the z carriage. Pics are of the item, how little the clearance is, three of the most recent prototypes (showing how thin the 'top' has to be), and a number of my earlier versions and mangled prints. This is my first project I've done and published. Bolt is a 3mm flat head (pan?) screw from True Value. It has a hex key in the head.