i3 y-idler with tensioner

I was having difficulties tensioning the belts on my i3. So for the y-axis I created a new version of the idler with an integrated tensioner. It was easier for me to just create the design from scratch although if requested I can do an openscad version.

3D printer parts and enhancements

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Printed in PLA with .25 layers and 60% infill. The bridge is challenging but if your printer is tuned it shouldn't be too much of a problem.

I've also added two nuts on the support rail so the idler is held in place but can still move when tensioning.

Edit: Changed the shape to octagonal to avoid extreme overhangs before big bridge.

y-idler...3mm - 3mm bearing hole for 623

y-idler...4mm - 4mm bearing hole for 624

Also: There seems to be a design very similar to this in the box_frame repositoryhttps://github.com/josefprusa/Prusa3/blob/master/box_frame/y-drivetrain.scad

Materials and methods

- M3x20 bolt
- 2 * M3 nuts
- 2 extra M8 nuts for lock nuts



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271bd29307139f614237353b4d066254?default=blank&size=40mkikia added this to the Prusa i3 collection ago
0fd2e6fe9cb729230eba89f306de3f75?default=blank&size=40Mike Benton added this to the RepRapGuru collection ago
7eb09ef83e65758030525ddafc2d395e?default=blank&size=40SirMoo added this to the things to make collection ago
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Mini 3davatarPaulo Rodrigues added this to the Utility Stuff for 3DPrinter collection ago
64f8de1412c9f5cc90662efceba76874?default=blank&size=40xrajox added this to the Prusa i3 collection ago
Mini me 300by300Richard M published this design ago