Great clamps!! They have a deeper reach that any other bar clamps I have seen.
They would be just right for working thick stock, as in 3-4" thick or so. All other only cramp the outside edges.
Oh, if electrolysis leaves tough back stuff on your tools? A quick did in any kind of acid dissolves it instantly. But then you have to scrub with baking soda to kill the acid.
In the case of cast iron like these clamp heads, once you get them dry rub down with a coat of boiled linseed oil.
Use your fingers so you don't have soaked rags of it laying around, and merely wipe the little excess at the end.
Cast iron and linseed go together like ham n eggs!
Overnight the iron will become pitch black and shining, and its a pretty sturdy finish too.
yours Scott