Accessories for Atlas Lathe Change Gears: gear-Lock, bushing, bolt, nut, drive shaft support

thingiverse

These accessory parts are designed for the Atlas gear changer system. You can find more information about it at https://www.thingiverse.com/thing:143893. The gear lock is what connects the rotation of one gear to another. I have not tested all these parts yet, and I'm unsure if 3D printed plastic will be strong enough for them. It's likely that they would work better in materials like ABS. The bushing fits inside the gear lock, while the bolt goes through it. I suspect that plastic may not be strong enough to hold up well, but I included these parts because it was easy to model them. I printed my bushing with nylon and found it worked really well. The drive screw support is a replica of the original part designed for holding the far end of the drive screw in place on the bed. This component should be a bit weak so that if the carriage crashes into the headstock, it can break away to prevent further damage to the lathe. I included both an STL model of the exact original part and one with additional support. However, I discovered that when milling threads, the 3D printed version of the original part wasn't rigid enough (printed in nylon), causing the carriage movement to be non-smooth. I then switched to the sturdier version and haven't encountered any issues since. These parts need to fit together precisely with each other and the gears. I included a printer_tolerance parameter in the OpenSCAD file, which users may need to adjust for their specific printer to ensure that the printed measurements match the desired size. This takes into account the inherent inaccuracies of the 3D printing process. The gear lock size was modeled after an original part from my lathe. However, I found that the 3D printed gears (see the link above) were often thicker than their original counterparts. This made the bushing and gear lock too short by about 4.6 mm. It's possible that not all gears are of the same thickness, but I haven't measured them yet. Others might need to adjust the code to change the bushing_gap variable to achieve the desired part thickness.