About this 3D model

I recently came across the Open Source Optics collection by jpearce (it's really great, you should check it out: http://www.thingiverse.com/jpearce/collections/open-source-optics), and I came across the M3 hex thumb screw on there. It seemed to me that there was no way for this to be held in place, as these nuts are rounded, and also these have to be fitted *before* the screw is in place. I thought I could do better, so I have designed this press fit version, which should not spin. **EDIT** The original version had some bad things going on in the SketchUp file (some faces were missing/reversed). The new files should be fixed and printable now.