About this 3D model

In an effort to teach myself how to model (slightly) more complex, and interlocking shapes in SketchUp; as well as being disgusted with how expensive these stupid things can cost I decided to "make" my own. This set includes dongles which should fit 1/4", 3/8" and 1/2" drive sockets; labled 25, 375 and 50 respectiely. I must point out however that my 3D Printer is on back-order so they are **COMPLETELY** untested however I *think* I did the math right and gave proper clearances. The STL's load fine in both Cura 13.06.4 and Repetier 0.90c; as well as a "virtual" print in Repetier runs fine. Cura reports a cost of ~1USD per rail assuming a cost of ~30USD/kg of ABS @ 75% Fill, the dongles being ~0.15 to 0.21USD depending on which size at the same fill. The rails have little nibs on each end stopping the "dongles" from sliding off once you squeeze them on; and the dongles themselves have nibs which should keep your sockets reasonably secured. The rails measure 180mm; which *should* fit on a 150mm (6") print bed if you rotate it 45 degrees. Also listed is a "one sided" rail, with nibs on one end only so you can glue or ABS fuse two rails together. If anyone actually prints these off; please post a comment and picture of how it turned out; I'd really like to hammer out any kinks before my printer actually arrives :-D