I bought a cheap 3d printer off ebay. It was mostly good but I have had to replace all the bearings, and in doing so I have decided to make my own housings that use zip ties to hold them in place. This is a 2 bolt and 2 zip-tie design with a really low profile for use with a prusa i3. Uses 4mm screws and nuts. I've also included the origin blender file I used in case anyone wants to have the original geometry in all quads for editing... OK not ALL quads, but pretty close.