Shopsmith Forums

RFGuy wrote: ↑Sun Nov 07, 2021 6:40 am

dusty wrote: ↑Sun Nov 07, 2021 6:33 am "Chuck it in the headstock" .....this is what confuses me. How does this work? What is needed at this point is a reference that is perpendicular to the face of the saw blade (perfectly aligned to the axis of rotation of the drive shaft).

Thanks Dusty. I agree. I was confused by the description as well. Hopefully Steve will post a picture or two and some more details.

I'm glad that JPG understands this but I am still not on board with this.

Chuck it in the headstock???? .... to establish a reference surface??? You have more faith in your chuck than I do in mine. Furthermore. once I have adjusted my main table (for horizontal - I calibrate the dial and then trust it as a rough indicator. If I need precision for this task I use other instrumentation.

Put the 1/2" 'shaft' into the drill chick or router arbor.

The bottom edge of the shaft defines a line parallel to the quill shaft axis of rotation.

Raise the main table up under the shaft. Adjust the table tilt until it touches the bottom of the shaft all the way across the top.

At that point, the table is parallel side to side(l/r) (0° tilt) to the rotational axis of the quill.

Nothing more than that.

Last step would be to set the tilt stop and the scale.

What I think is going on is that he chucks rod into the drill chuck with the rod sticking out above the table, then raises the table and adjusts it until it contacts & is parallel to the rod. At least I think that’s what’s being described. Seems like it should work….

JPG we cross posted

That's it in fewer words!

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.

Get off the drill press train of thought.

If I am correct, only the table tilt is being set.

A drill press operation requires alignment in BOTH horizontal planes.

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

Geez guys, does it hurt to wait for the OP to respond? We have 2 pages of comments now with different interpretations of what he said. I asked a question, but it is no clearer to me how this is an improvement on existing alignment techniques. I am not saying that it isn't, but oftentimes threads like this one go off the rails because we don't wait for the OP to respond. I'll check out of this convo for awhile...

+1

We 'traditionally' think of using a square and a flat plate(saw blade sanding disk or precision plate). to zero out the table tilt.

He describes an alternative.

How many of us have a precision 1/2" ball slide shaft.

If not ignore this!