M3D ProMega filament guide

thingiverse

Simple yet heavy-duty filament guides for M3D ProMega, designed specifically for the backpanel and utilizing the top screw on the backpanel for mounting without the backpanel in place. A necessity to avoid hitting the drive motors when printing. The design consists of three pieces: a mounting support, a "capture block," and an arm, created to simplify printing and maintain modularity for ease of development. Three captured nuts (3D threaded heat inserts) are strategically placed on the "front" of the support and two on the back to ensure the capture block remains securely in place. This is crucial due to the high torque on the arm as the filament passes through the bowden tube. For a smoother printing experience, consider removing or shortening the PTFE bowden tube to reduce drag. However, this may result in some noise from the guide arm dragging against it. Alternatively, you can remove the bowden tube altogether and rely solely on the guide arms for smooth filament flow. The alignment of screw holes between the capture block and support is quite precise, but a slight redesign could incorporate some slack into the notch that holds the capture block to facilitate easier assembly. Two complete assemblies are provided, one for each side, as the ProMega printer comes equipped with two spool holders by default. The parts can be reversed or just the support rearranged without significantly affecting the overall design's symmetry, except for a minor offset in the guide arm's centerline that is unintentional and should not impact assembly. **Update 1** The initial version of these guides relied on "plastic against plastic" to manage filament flow. However, at steep angles, the filament sometimes bound up against both the support and exiting the arm due to its friction against the plastic. To address this issue, the updated design widens the filament feed holes so that the bowden tube passes completely through it, allowing the filament to enter and exit only against PTFE. This modification significantly improves printing smoothness. Please note that the provided pictures show the original drilled-out versions but illustrate the feed path effectively. **Acknowledgements** The connection method of the guide arm to the capture block was inspired by the "2020 / Ender 3 Filament Guide" design, which can be found on Thingiverse (https://www.thingiverse.com/thing:2917932).