MPCNC Primo Nema17 drag chain mounts

Drag chain mount for MPCNC Primo, remixed from thing https://www.thingiverse.com/thing:4613811. I chose to attach the drag chains directly to the Nema17 steppers with a design that straps around the motor and kept in tension with a screw.

The drag chains i used are Sunhokey 15x20mm, purchased from https://www.amazon.com/gp/product/B07MJPBV4Y. I needed four of them since i have a larger machine (3x5' footprint).

For the drag chain from the gantry, I used a simple aluminum angle to give the drag chain some support to rest on (it's ok if it's only on one side). This was inspired by https://www.thingiverse.com/thing:4635424 but created from scratch for my application.

Update April 16, 2021: added J and F size clamps.

Print Settings

Printer Brand: Prusa

Printer: I3 MK3S

Rafts: No

Supports: No

Resolution: 0.2mm layer height

Infill: 20%

Filament: Prusament PETG Black

Post-Printing

In my setup, i have three drag chains.

The first drag chain is on the left, attached to the motor using part nema17-mount-yleft.stl, and leading to the rear left of the machine. This drag chain has all motor and endstop cables for the y-travel direction. The cables from the right-hand-size motor are routed inside the pipe to the motor truck on the left.

The second drag chain is connected to the gantry motor using nema17-mount-gantry.stl, and is angled and elongated in order to meet up with the drag chain support underneath. This drag chain contains the z-axis wires, endstop, and could also have your router/laser/probe wires if you want to.

This drag chain rests on a narrow aluminum extrusion (15x10mm) which is mounted to truck_clamp_c_primo_raised.stl and truck_clamp_c_primo_plate-small.stl on the front the machine, and parts truck_clamp_c_primo_raised.stl and truck_clamp_c_primo_plate-large to the rear of the machine. The drag chain is screwed to truck_clamp_c_primo_plate-large using an m3 bolt and nut.

The third drag chain is in the rear, attached to the read x motor using part nema17-mount-xrear.stl. This is a mirror of the nema17-mount-yleft part. This drag chain has the x-motor wiring and endstops, as well as the wires from the gantry, and leads to the rear left of the machine.