I needed a replacement for the knob on my Work paint scraper, so I modeled one similar to the original.

The step file can be used to extrude it a bit longer if needed. This one has about the same height and shape as the original.

Mounting

Like the original, just screw a bolt right into the plastic. Usually it lasts for long, but the screw hole on the original was worn out on mine after some tough work against concrete floor.

Printing instructions

I used 4 perimeters. 0,4mm nozzle and 15% infill. I printed it in ABS.