Ring Gear and Pinion

thingiverse

This is a basic ring gear with 54 teeth set at one-eighth inch spacing. The hub was made to fit a standard one-quarter inch shaft on the ring gear. A pinion gear has a one-eighth inch shaft hole and ten teeth. I did not include any shaft lock recess, such as a key slot or flat or set screw holes, in order to let you design your own into it. For precision, I usually bore out my shaft holes and either machine from aluminum or three-dimensionally print a new custom shaft hub designed to fit my motor output shaft and just glue or screw it into the gear model. So, the axel holes are more or less just centering holes, although they will accept standard shaft sizes as is. My purpose for this gear arrangement was to move the bulk of the motor drive above the large wheel axel. This gear set was originally designed in order to move the wheel motor above the drive wheel axel for ground clearance. This was for a heavy-duty rock crawler/ATV rover I built. There is a disadvantage, however; dirt and debris can collect inside the gear and cause problems. Thus I made the gears rather coarse and oversized to pretty much tolerate sand and such. Still, pebbles and sticks can get in there if you are not careful. The gear ratio is 5.4 to one, so it is pretty low for really great torque, especially if the drive motor is a geared DC of something like two hundred to one. The ring gear can also work great as a turret rotator for a crane or model tank or battle ship. The overall diameter of the large gear as presented is 2.4 inches and the overall diameter of the pinion gear is point four six inches. I use PLA filament, bed temperature fifty degrees Celsius and nozzle temperature two hundred fifteen degrees Celsius.