Nerf Longshot Bolt
These knobs always seem to get lost. 3D printer to the rescue!
To assemble, I bought a piece of steel rod from the hardware store.
Before attaching the knob, I sanded down the rod slightly, so that it was smooth.
Next, I used a hairdryer to heat up the knob, then press the rot into it. Super glue can also be used for a more secure connection.
because the length of the rod varies between longshot, vulcan, and centurion. I ended up sticking the rod through, and eyeballing it.
So far, it's working well.