Ultimaker 2 UM2 GT2 belt coupler

thingiverse

This is a GT2 belt coupler that allows the use of open belts on Ultimaker 2 printers. It fits inside XY carriages. To use it: Cut the belt with 1 or 2 cm of extra length, then put a coupler on each end of the belt (the belt must be already on the pulleys of the printer). Put both couplers side by side, tensioning the belt, then measure the length that has to be removed. Cut the extra length (the pitch is 2 mm on a GT2). You may have to cut 2 extra mm to get good tension or use an extra tensioner (don't cut the belt too short or you won't be able to use your tensioner). Assemble the two half couplers, side by side, by pressing them (put a 4 mm diameter screw through both holes can help a lot to keep alignment). Don't try to put both belt ends on the same half coupler, that's too hard to do. Put the original XY Ultimaker carriage back. Notice: My XY carriage may not be genuine, so I'm not sure it will fit in certified UM2 parts (let me know!). This part may need offset/scaling because it has to fit perfectly in the XY carriage (to prevent backlash). My reprap is not working yet, so I can't test it in real conditions (let me know again). A pulling test showed me that the belt is slipping around 18 Kg. This should be okay because the working tension of this kind of belt is around 2.5 Kg. Printer Settings: Printer Brand: Ultimaker Printer: Ultimaker 2 Rafts: No Supports: No Resolution: 0.15 mm Infill: 100% Notes: Cheap (but good!) white ABS from "grossiste3D". 220°C, speed 2500 mm/min, no fan, 0.4 mm nozzle. A few mm of skirt. 100 °C buildplate, Printer closed (A3 sheet container on top, plexiglass on front), acetone/ABS mix applied on cold build plate.