My PrintrBot Simple 1405 was giving me fits tonight so in a moment of extreme irritation (and since I can't fall asleep) I tore it down and rigged the board, extruder, extruder motor, hotend and endstops onto my ShapeOko based CNC router. I'll eventually be purchasing a SmoothieBoard to do both 3D and CNC routing on the machine, but until I have the free cash this seemed like a fun thing to do. My only concern at the moment is that I don't have a lock collar or jam nuts to take strain off the coupler, so it is holding the z on its own. I'll stop by a hardware store tomorrow to remedy this. I've been thinking about springs as a possible solution if I can't find the nut or lock collar that I need.
The machine has dual y motors wires in parallel, and once I have the Smoothieboard it will have hard limit switches. I revised some of the original ShapeOko plate designs and I had them all cut from 1/4" 6061 aluminum. The X is a 40x40 piece of extrusion with OpenRail bolted on. Y and X are belt driven, Z is screw driven. I took the Delrin nut PrintrBot provides and hacked about 1/8" off each side then mounted it on top of my existing 8mm Delrin nut by drilling holes in the Delrin block. Eventually (and before I do any milling) I'll replace the screw with a 3/8 acme setup someone on the ShapeOko forums sells.
It is printing well so far, but I can already tell the springiness of the collar combined with the weight of the Z is an issue; the nozzle is dragging just a tad in certain spots. Also, since the machine has a 375mm x 500mm profile and it is bolted to a piece of particle board it shakes my desk quite a bit, but the overall noise is lower than the Simple.
Eventually it will have a build area of roughly 12" x 8" x 5". I've got some thoughts on how to increase the Z, but it isn't a huge priority right now.
This was all thrown together spur of the moment, so as you can see my work area is ridiculously messy and the wiring is not too pretty.
Here is a video:
Photos:



