Hi, I made the vise shown hear some years ago, made it out of an old coffee table top, mainly to hold guitar bodies for scraping or sanding the sides and other work.
As it would be ideal for holding boxes for the same jobs I thought it might be of interest here as a cheaper alternative to a shop bought one. I can also see ways to modify it further to make it "mobile", so those of you that work off of the kitchen table can attach it when required, and remove it before the wife comes home.
I think the photo's will tell the story. Half inch threaded rod can be used, but would be sized according to the size of the vise jaws.
The threaded rod goes through nuts that have been embedded into the back board and capped both sides with suitably sized washers to keep them in place.
there are a number of ways to make handles for the ends of the rods, what I used was already in the "parts" drawer.
I made mine to fit into my "island vise stand" but you can get creative as to where and how it mounts.
If I had made it to fit on to the front of a bench I would have had two more nuts spaced out so as to give more rigidity to the two threaded rod and the moving vise jaw. But as it is it worked fine for 20 years.
Forth picture shows it off nicely. Really dig your handle idea.
That's a nice vise.
Now let's see the bike!