Dear home eng, thanks heaps for your video, you explain it well it's obvious, much appreciated. Guess whos been doin it wrong for years??
Dear home eng, thanks heaps for your video, you explain it well it's obvious, much appreciated. Guess whos been doin it wrong for years??
thehomeengineer (Sep 26, 2022)
Different maybe, wrong perhaps not. Vise condition is the factor; thehomeengineers is the go-to test for most conditions, especially where 1 edge of part is dependable.
I'm 1700 miles from my equipment. I'd like someone conduct a test.
Indicate hard jaw, then movable jaw with and without a very good cylinder (or a thick parallel) clamped in the jaws. It's common to find deflection if the round is parallel to vise bed, but 'hide' the discrepancy if not. A vise 'sees' an inclined cylinder as a flat. In the past, have found results of loose lock-down vise adjustments that lift cause it to incline without loosing parallel, just perpendicular. Cylinders are good to aggravate that tendency.
Regardless vise position, a long part is best indicated itself, whereas jaws only hold a portion. For dual vise setups, I like a length of Thompson bar, TGP (Turned, Ground, Polished) or drill rod. I indicate one vise at right or left end .0001 and tighten down. Clamp the rod into that vise, and the 2nd floating on the table (no fixture keys). Lock down vises are secure enough to pull the 2nd into register with the first, but worthwhile verifying with indicator.
If a part with height needs real accuracy, I mount a true flat into jaws vertically and test the quill and knee or sliding head.
This makes a partial substitute or preparation for surface grinding, having really parallel or perpendicular surfaces on a workpiece.
Sincerely,
Toolmaker51
...we'll learn more by wandering than searching...
If you tap to get zero as it moves along, chances are that you only make one pass! Once zero is steady you are done. If you have problems as Ralph mentioned your pivot is moving. Try to improve the quality of your pivot. I.e., Bigger bolt, sleeve the bolt, seat bolt against one side of the ways, etc.
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