Helical Gear Bed Level Knob with Captive Nut

thingiverse

I really like the "Captive Nut" idea, and I make a lot of gears, so I thought I would combine them in this print. I didn't use the Cura plugin to pause the print. Instead, I monitored the percent status on the Anet display and paused at 65% to insert the M3 nuts. I had calculated the layers in Cura (I think it was layer 46 of 69 total) just before it would start to close the hex pocket. It worked great. I modeled this in Fusion 360 with the Helical Gear generator, then modified it with the hex pocket and thru hole. The pocket is 0.1 inches deep and the M3 nuts I used are 0.093 inches long. This is to ensure you can insert the nuts fully and be below the print layer that will cover them. Make sure the nuts are pushed in as far as they can go before resuming the print, or you risk running over the steel nut and damaging the print nozzle! (I learned this the hard way). Thanks to Ratm3at for the inspiration to try this! This goes great with the Spring Bushing by Puddlefist.