Warning: you need a vise to press the existing knob to the print part.

Bought some cheap knobs and it's too small to handle. I enhanced it by designing a bigger, better and easier to grip knob. This knob can be used for building a jig like a table saw tapering jig or router table fence, etc... Have fun and be safe!

I recently added a new knob and all you need is 5/16 hex bolt. Please check it out https://www.thingiverse.com/thing:4092649