OK, not making this up....
While I have never seen a square key setup that way, in lots of machine setups, and especially tool and die setups, it is real common to have a steel dowel pin with a threaded hole through it lengthwise.
In that case, the dowel is usually a tight press fit, and put in flush. You do not screw in a screw and pull, you would not be able to pull it out.
Instead, you lube the screw well with some high pressure lube, screw it in until it goes all the way through the pin and hits the bottom of the hole.
Then, you keep turning, and the pin rides the screw out. In this case, the screw in question is called a Jack screw, and removing the pin is called jacking it out.
All very well and good..........
Sometimes wheels and pulleys are pressed onto a hub the same way, and have jacking holes to remove them. Usually several around the hub that are tightened a little at a time all the way around so it puts even force on the pulley.
They were having a kinda open house at a tool and die shop I was consulting for, and were doing the whole tea and crumpets type thing.
Lots of dignitaries and their wives.
Work had to go on, but we were all on our best behavior while they were touring the shop.
I was waist deep in a big turret lathe trying to figure out a feed control problem, when I noticed a new guy about to hook a big puller onto a spoked wheel on a very expensive machine that had a bearing problem. I knew that the cast iron wheel would snap and the machine would be down for weeks until we ordered one from Switzerland.
By the time I saw it, he was just getting it tight, and I was still a little distracted by what I was doing, so I didn't think what I was about to do all the way through.....
In a slight panic, I yelled across the large room, " Don't pull on it, Jack it! You got to jack it off, jack it off, don't just pull on it. "
Ever tried to hide in a Warner Swayze turret lath? I just quietly squatted down and closed the doors.
