Motor Mounts with Clearance for 1.5GT Pulleys on Upgraded CORE One/+/L

After installing the 1.5GT belts and pulleys for the Gen2 upgrade on my CORE One+ printer, one of the new pulleys was rubbing on a curved guard built into the stepper motor mount. It made a hard-to-locate scratching sound while printing and it affected print quality a little bit by causing some uneven layer stacking.

Looking at the CAD model , you can see that there was originally a 1.0mm gap between this guard and the rim of the old 2GT pulleys. The new 1.5GT pulleys have a larger-diameter rim that closes that gap to 0.45mm . In the actual printed stepper motor mounts, that gap is even smaller . Using the movement around the screw holes, I can shift the gap between about 0.35mm and 0.15mm, measured with feeler gauges at the very edge of the guard. At its closest, something on the interior of the guard face that I can't see makes contact with the pulley rim.

You should be able to avoid this problem by pushing the stepper motors toward the rear of the printer and pulling the mounts toward the front of the printer while screwing them down. To me, that gap is still a little too close for comfort. So, I modified the motor mounts to restore the original intended 1.0mm clearance around the new, larger 1.5GT pulleys. This is probably not necessary, but I view it as an easy extra bit of insurance to swap these out while you're building your new printer or tearing it down to do the upgrade.

Printer Compatibility

These stepper motor mounts are drop-in replacements for the ones that come with any of the CORE One or CORE One L printer variants, both with or without INDX. They only increase the clearance around the stepper motor timing pulleys, so they are most useful for the upgraded CORE One+ Gen2 or the upgraded CORE One L+ printers (or their INDX variants) that use the larger 1.5GT timing pulleys.

Printing the Model

Use a 0.4mm nozzle and default slicer settings with the 0.2mm STRUCTURAL profile . This model should be printed with Prusament PC-CF filament to match the rest of the printer, although any filament with a HDT (heat deflection temperature) well above the maximum chamber temperature will work (because the stepper motors themselves will get significantly warmer than the chamber). Materials like ABS/ASA/PC Blend will also work well.