Drive For Big Gears

Drive for my big cogs for steampunkt installations.

It uses a tiny motor (RF-300CH) to propel the cogs. The power consumption is very low, it can easily run on batteries.

The gear reduction relies on an rubber band. This limits the torque to protect fingers from being squished by the cogs. This method is also very silent. The down side is that the rubber bands don't last very long. But replacing is quite easy.

I recommend to remove some grease from the bearings by washing them with WD40. This save some torque.

Inside the cog two spacers (consists of two "SpcIn.stl") are used to free the bearings from axial pressure.

The drive is to be mounted in an cut-out in the wall of an case. To cool the motor a small duct conducts so blowing of the cogs to the motor cavity. To let out this air the tiny hole beside the motor should not be blocked. In my experience the motor never got worm.

The bigger hole, witch also continues through the rear bracket, forms a plug when when pin headers are installed. This plug comes in handy when the rubber band must be replaced.

The photos above are showing an prototype. In the final (published) version i swapped the 608 bearings for smaller ones.

A short demonstration can be seen at my Facebook Video or an other video or at this video and last but not least this video

To make sure your installation is indeed safer you must check the real risk in your installation. Please notice I am not responsible for your installation.

BOM
2x 685 ball bearings
1x RF300CH Motor (often referred to as "solar motor")
1x rubber band
2x M4x25 countersink screws
3x M3x12 countersink screws
1x M5x50 countersink screw
1x M5 nut

See my other Steampunk designs in My Steampunk Stuff