RFGuy wrote: Sun Nov 07, 2021 10:02 am
So, what is the benefit then unless you do precision work in drill press mode frequently? I mean, I wouldn't assume 0° error between a drill chuck and a saw arbor. I primarily use my Mark V for tablesaw, jointing and lathe operations. Doing the prescribed alignment in this thread won't necessarily give me alignment between the sawblade and the table ensuring a perfect 90°. Or am I still missing something here? I think some assumptions are being made here that a sawblade arbor and a drillpress chuck are ideal and no axial angle errors (systematic offsets) exist between them.
The objective stated in an older manual: "The table surface must be aligned so that is is parallel with the main spindle when the table tilt is set at 0." There is a picture showing a line extended from the quill spindle similar to what the OP is describing.
No method that we use provides a perfect reference, so I'm open to the possibility that this method may provide a better reference. It is simpler, in the sense that there are less variables creating error. (KISS principle.) And the alignment itself is much simpler. Which does not mean there is less error, but it is at least possible. The good part is that the error is quantifiable, IIUC the error is the total runout of the mounted cylindrical shaft. (Meaning combination of spindle runout, chuck runout, and shaft runout.) Quantifiable and measurable error to the axis of rotation IMO, but perhaps not with tools we all own. Contrast this with mounting a sanding disk, saw blade, or whatever, determining the high and low points (sometimes just the high point) at some distance from the center, drawing a line through those points that theoretically represents maximum deviation, then drawing a perpendicular line and saying it is minimum deviation. Is it? Is its deviation measurable or quantifiable? I think we are just saying it is a 'good enough' representation of the plane of rotation. That doesn't preclude a better one or one that is easier to align to.
- David