Stepper motor with worm gear for operation of air valve

thingiverse

I needed an air valve for my basement that could be automatically operated via Arduino electronics. The commercial valves available were too expensive and too dull, so I bought a manually operated valve and built a gearbox to work with a NEMA 17 stepper motor. The gearbox has a 25:1 ratio, giving the stepper motor enough power to operate the valve at 60 rpm. A flange is included for attaching another small electronics enclosure; later, I plan to install the stepper motor controller there. My gearbox design was based on the Thingiverse model https://www.thingiverse.com/thing:1924502, but I completely redesigned the housing for this purpose. In the original design, the screw gear pushed the bearing out of the housing when operated, so I added a cap to prevent this. The screws used are 3 mm sheet metal screws. The bearings used are 625ZZ. The axis for operating the air valve was also printed; it needs some fixing with plastic glue to the gear to be tight enough. It could be replaced with a metal part, but I didn't have one and wanted to print as much of the parts as possible anyway, and it works fine like this.