Pulley Thread Fix

thingiverse

I recently encountered a problem with the pulleys that come with my Velleman VERTEX K8400 printer - they have very short threads that are prone to damage. Instead of replacing the entire pulley and facing the same issue again, I devised a simple solution. A 3D printed ring with a much longer thread is placed over the pulley, securing it in place with a mounting screw that passes through the original hole in the pulley, which needs to be slightly widened. This ring was specifically designed for K8400 printer's pulleys, which are mounted on 8mm rods. Given its simplicity, you can easily create your own ring tailored to match the dimensions of your pulley. UPDATE Unfortunately, this fix only lasted two months before the threads in the rings began to loosen. While printing rings with PLA or ABS may produce better results, I decided to tackle the root cause by replacing the rare 19T pulleys and GT2.5 belts used in VERTEX K8400 with more widely available and cheaper 20T pulleys featuring longer threads and GT2 belts. I am now waiting for these parts to arrive, and will post an update on whether this replacement is successful. UPDATE 2 I successfully replaced the pulleys and belts, and you can find the details here: http://www.thingiverse.com/thing:1857266 Print Settings Printer Brand: RepRap Printer: VERTEX K8400 Rafts: No Supports: No Resolution: 0.1mm Infill: 25% Notes: I printed rings with Brim, but they should stick without it as well. Material: PLA Post-Printing Assembly Widen the holes in the pulley to ensure the M3 screw can pass freely through them. Use an M3 hex socket cup screw to cut a thread in the ring. Place the ring over the pulley and align the holes. Fix the pulley with the ring on the rod using an M3 4mm or M3 5mm screw.