Hi, I also do it like Darebee, but I also have a flat plate that I lay across the bed and use a square to get the front face of the job vertical, then just put a dial indicator on my surface gauge and run it across the top of the job from the back, rotating the chuck to get the other side and split the difference when adjusting the top and bottom jaws.
When I worked in UK I had a square job weighing several tons in one of those big faceplate lathes.
The only way to move the faceplate chuck was with the pendant control from up on the toolpost.
You started off by measuring the distance from the outer edge of the chuck to the job with a tape or 6 ft rule, and adjusted the jaws till you were close.
Then depending on what you were doing, IE, cutting down from a rough forging or casting, or if it was setting to a finished diam or face it would be close enough, you would then use the graduations on the top slide to wind in and out to get more accurate, turning the chuck with power to get the four planes.
Barring the chuck round was not an option as it took two to do it, one to move the chuck and one to get the position.
I used one crafty method, by marking a chalk line on the bed and moving the chuck to the four points respectively and marking the "cardinal" points on the chuck face in chalk.
Using this method required a dial indicator on a tool holder on the top slide so that the crosslide could be wound in and out under power while you barred the chuck round to the four points, and allowed you to see the zero from down on the ground.
Ian.  |