3D printing has exploded as a viable method for amateur fabrication and has correspondingly made waves throughout the hobbyist community. After learning the 3D printing process through experimentation with my own printer and help from online resources, I wanted more. Because my printer was derived from an open-source kit, I was able to obtain the design files and modify them to whatever extent I wished. Over time, I have replaced almost every component on the printer including the electronics, mechanical interconnects, extruder, tool head, and motors. Many of these modifications were fabricated using the printer itself.
Two lightweight E3D-v6 hot-ends are affixed to a small mount, printed in PETG (chosen for its strength and low density, a desirable combination for a rapidly moving print head). This structure connects to the tool head – also printed in PETG – via two M4 bolts with springs pushing outward between the tool head and the hot-end mount. Locknuts are affixed to the hot-end mount’s underside. This system allows the level calibration of the two hot-ends with respect to each other to be adjusted simply by tightening the bolts. The loop on the left of the hot-end mount allows for the addition for an inductive sensor so that the printer may detect the height of the bed in predetermined locations and calibrate itself at the start of each print.
The two hot-ends are fed 1.75mm filament through a PTFE tube via two NEMA17 stepper motors affixed to the top of the printer using a bracket printed in PLA. The PTFE tube was chosen due to its low friction, reducing the probability of filament jams. The two motors are tilted such that the tubes exit the extruder mechanism at an angle of 45°. This is so that the radius of curvature of the tubes remains large, regardless of whether the hot-ends are at the bottom of the Z-axis or the top, thereby reducing the probability of a filament jam.