Mochaboy's "Tool less" Tensioner Printrbot Jr / XL and GT2 belts

thingiverse

Updated 8/10: Added bracket for GT2 belts; suggest printing the bracket at .2 layer height. This part has several design objectives: use readily available Home Depot parts, be tool-free, and avoid damaging the fascia. It also eliminates the need for toothpicks. The tensioner consists of a top belt catch, two 14mm adjuster knobs, and a bottom captive plate/foot. Required items include: * 4 x M4x30mm Hex Bolts (from Home Depot small parts section) * 4 x M4 nuts Assembly notes: 1. Skp files are accurate to within +~.25mm. Adjust as needed or print at 3-5% extra scaling for a perfect fit. 2. The top plate's bolt channels should have minimal play but allow easy bolt passage. Adjust with a drill bit if necessary. 3. Captive nuts should face the bottom/foot of the tensioner. 4. The foot secures parts and protects the wood from damage. It fits over the cap screw due to its cavity. 5. After around 50 hours of printing, belt adjustment was needed; however, with the knobs, it's now effortless. Enjoy!