Made a diy leg vise from junk / surplus that i could found.
Its not a beauty, but works for me.
Traditionally leg vises are based to threaded rod with a big diameter, that supports / alings vise straight. Some extra guidance can be get with dowels etc..
But, big screw is the "main" thing.
Those are just hard to find for cheap.
I wanted to found alternative way to make a leg vise.
If you watched the video, you might notice, i didn't need to use any extra supports on the long end of the clamped piece. Vise holds well and is easy to make.