Modified Promega rear cable chain mount

thingiverse

This is a remix of the rear cable chain mount for the M3D Promega printer. The original is posted in the Promega Public Google Drive, linked on the Promega support site: http://promega.printm3d.com. You will need an M3x25mm flat head screw and an M3 heat insert in addition to reusing the chain attachment and M5 anchor hardware. The following improvements were made: 1. The "bridge" above the motor mounting screw now has a vertical slot to allow a thin screwdriver to be used on the screw without having to disturb the chain mount. If you use the horizontal slot in that bridge for PTFE filament feed tubing, you may have to temporarily remove the tubing when adjusting motor tension. I feed all my filament from a dry box above the printer, so it's not an issue for me. 2. The screw and lock nut at the anchor point in the unused motor mount screw slot has been replaced with a flat head screw fed from the bottom and a heat insert embedded in the top of the chain mount. This allows the motor to have full range of motion on the mount. The slot must be countersunk so that the screw head is flush with the bottom of the motor mount (see photo); I used an 82-degree countersink bit I got at Home Depot and a drill press.