Silvan wrote:
The big block that the screw runs through moves. The four holes that the
rods go through move a little when I whack them. I still can't turn it to
save my life. I think the business end of the screw still has rust deep
inside. That area hasn't really started to turn black yet either.

I apologize for missing this thread till now. I have a Morgan Vise a
friend gave that I was able to break loose with liquid wrench. He told
me he got it from his uncle who'd been using it since the fifties, and
he believes it was old then.

What I found after I'd gotten the screw turning was that it was, for
lack of a better description, the "quick-slide type": the screw itself
only turned about two revolutions before hitting a stop in both
directions; there's a slot in the screw and when it's in the right
position, you can slide the face back and forth, to where it touches the
piece, then tighten it with the screw.

Is it possible you've got one of these, and you're at the end of the
spin travel in one direction or the other? In my case I was trying to do
just that with a piece of pipe in the screw handle, then after the third
treatment of LW I reefed it the other way and nearly fell over when it
broke loose.

Haven't looked at it for a few weeks and I can't leave work right now to
go check it so I might be remembering a few things wrong. Maybe I can
take a few pictures this weekend to see if it might look like yours.
From your description, mine is definitely smaller. :-)

Dan