Work In Progress: MoCo Dolly

The head bearing, coupler, stepper motor, and assorted bracketry and mechanical bits. The assembly worked at this point, but I hadn't finished wiring in the limit switches or bundling the wiring together. One twisted wire on either side of the bearing block actually runs through the inside of the slide to the limit switches flanking the tail bearing, the other runs through the first head bearing, out the bottom of the second, and to the head-end limit switches. The idea is to conceal as much of the wiring as possible.

After the wiring was completed, the wiring was bundled together using heatshrink tubing and tied down with P-clamps mounted using two of the motor bracket bolts (seen under the coupling).

Each end has two redundant limit switches, each of which can be read by the microcontroller independently. A quad OR gate also triggers an interrupt on the microcontroller if any single switch is closed, resulting in an immediate hard-stop of the carriage.

And yes, I know the motor hangs out, unprotected, beyond the plate. No excuse, just bad design on my part. I had plenty of aluminum - there's no reason I couldn't have made that plate another 35mm longer.