These knobs fit the standard 8mm encoder D shaft and provide some additional weight to improve the overall knob feel. I made these for amateur radio projects but they should be generally useable.

All these files are designed to use 4.5mm airsoft shot to provide the additional weight. "Hole" models are designed to have the shot friction fit into the holes. I used a tool to force the shot to the front before applying further layers. Versions of the "channel" type provide more space for shot but require epoxy to fix the shot in place. In my experience, I layered shot in with 5 minute epoxy, but it took several days to fully cure. Your experience may vary, but I recommend handling with gloves until you're sure that it is fully cured.

The knobs are a press-fit to the shaft and do not require or accept a set screw.

There are two different major diameter files provides, 20mm and 42mm. In addition, there are low profile versions of some of the designs to fit in my own specific enclosure. Generally, unless you need the low profile version I would recommend the normal height... otherwise there is only 0.5mm of material above the top of the encoder shaft.

I recommend printing front face down for best surface quality.