Added a few new OpenBuilds parts: ACME Nut Plate, ACME Nut Block, and Solid V-Wheel.
Added STEP and IGES versions of all part models, including parts in earlier version.
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V-Slot CAD Models for Autodesk Inventor Updated 4-22-14
A set of CAD models for the V-Slot extrusions, plates, spacers, and other parts.