Y tensioner for Anet A2

thingiverse

This is a Y tensioner module that fits Anet A2, Tevo Tarantula, and possibly other printers using 2040 extrusion on Y axis. Inspired by Banholm's Tarantula Y tensioner at http://www.thingiverse.com/thing:1704100, but I didn't like its size - it was huge. So I created my own compact version that doesn't share any parts with Banholm's. The sideplates are the same height as A2 stock sides and just 10mm longer (72 vs 82 mm). It has 10mm of adjustment, which is plenty for me. Print Settings Printer: Anet A2 Rafts: No Supports: No Resolution: 0.2 Infill: 70 Notes: I printed all the parts with 70% infill and was happy with the results, so didn't try any other options. With correct orientation, all the parts should print fine without supports. Post-Printing To assemble this, you need six M4x10 or M4x12 screws, one M4x30 bolt with a 7mm head, one M4 nut for tensioning, and six to eight M4x10 bolts plus T-nuts for mounting it to the 2040 frame. If you want to use M5 bolts/T-nuts, print with thicker walls (min 1.2) and drill the relevant holes with a 5mm drill - it should work fine. UPDATE: Don't use cheap Chinese 16t idler pulleys; they won't last. I'm using 16t idlers in the tensioner, but original flanged 623 bearings would work fine as well. Use the original flanged bearings with a 0.5mm shim between the bearings, or they'll be too narrow for a 6mm belt. Original M3x30mm screws can be used for the idlers, but they must NOT be tightened - the bearings/idlers must be able to rotate freely. I suggest using M3 nyloc nuts, two standard nuts tightened against each other, or a drop of threadlock to prevent loosening over time. Easiest is to assemble the inner slide first, then backplate plus nut (loosely), then add the sides and mount the whole assembly to the frame. How I Designed This