Hypercube 3D Printer X Carriage Mod

Slight modification on Tech2C's wonderful Hypercube 3D printer's x carriage. This mod makes the left hand side belt clamp stronger by allowing the screws go from the back all the way to the front of x carriage. Also fill up the original nut holes which make it weaker (mine snap right over there when I tighten the belt). It was a pain to insert the nut into those tiny holes in the original design.