Sometimes a standard wood lathe chuck is just too large and/or cumbersome to open and close repeatedly for quick operations. I have a Jacobs 1/2 inch chuck mounted on a MT taper, but it only stays in place if there is pressure from the tail stock side. I have been looking for an adapter from 1 x8 or even 3/4 x 16 to 1/2 x 20 so I can mount a keyless chuck to my headstock spindle. I could buy collets, but they are so expensive compared to just a spindle adapter. I found adapters at a place like Graingers, but .I am told their tolerance could leave the center as much as a 32nd out of true center. (which seems pretty sloppy.) I would think others could use such a thing if it were made
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