I use my panavise (Jr) all the time, but often find myself having to crank by hand from one end to the other. No more with this simple hack. My trusty nut driver does all the work.
Step 1: Find a bolt
Find a bolt that will fit your nut driver. Almost all nut drivers are 1/4" hex. This was just an extra bolt I had around.
Technically, this is a hex washer head sheet metal screw, but that's just the engineer in me speaking.
Step 2: Mark the center
I wanted to drill as close to the center as possible so that the vise and driver don't shake in use.
I used the center finding gauge from my tri-square. There are more complicated ways of drilling in the exact center of a circle but this worked for me. I used a knife to scribe a few lines through the center at varying rotations.
Step 3: Find a drill bit
I used an 1/8" drill bit for the hole. I didn't want to split the knob on my panavise so I used a size that was just a bit bigger than the shank of the screw.
Step 4: Drill into the end knob
Next drill your hole in the center. Even with the center marked it was hard for me to get it just right. If I had to do it over, I probably would have drilled a smaller hole first just to help get the center right.
Don't drill too deep. Mine went in about 3/8 of an inch and then brass shavings started coming out. Definitely stop when you see brass coming out.
Step 5: Test and cut to length
Before you cut your screw to length, give it a try in the hole first. This way you'll know that the hole is the right size and it gives the self tapping end of the sheet metal screw a chance to cut some threads for later.
I cut my screw to approximately 1/4" long. I could have left it longer but I wanted to be on the safe side.
I used a jeweler's saw to cut the screw. Most people would use a dremel tool for this but I've never really liked using mine.