What affects getting a square crosscut with the miter gauge

[BuckeyeDennis]

So far, I have resisted strong temptations to post on this topic. But now it's Friday, the hour is now late, and I have succumbed.

As an engineer with decades of product-design experience, I never miss an opportunity to learn from experienced technicians. They know tons of stuff that the engineering professors don't. And have very keen bullshit detectors.

Conversely, engineers are trained to never make assumptions. If it can go wrong, it will. And at the worst possible time.

Hobbyman2, if you say that your table is square to the miter slot, I absolutely believe you. I still don't know if mine is square (520 rail, that is) but I'll damned sure check it the next time I check my miter gauge. If it turns out to be square, that's a handy time-saving tip.

Conversely, just because your table is square, please don't assume that all tables are square. I actually know that you don't, because I "read the fine print", and I know that you qualified yours. But please be careful that your writings cannot be misinterpreted. Some of them could be misconstrued as saying that ALL tables are square to the miter slot, which could literally be dangerous advice to a newbie.

As for squaring the other miter gauge angles, I have to agree with reible and JPG on this. Your point may ring true if for a milling machine. But on a table saw, the tabletop itself controls both the "pitch" and "roll" angles. The miter gauge controls only the "yaw" angle. Which brings us back full circle to proper alignment methods.

Personally, I use a verified-true square to check the angle between the face of the miter gauge and the miter bar. But I'm hoping that my 520 rail proves square to the slot, so that I can use your time-saving tip. And also that the 520 miter-bar retaining washer doesn't screw up this method, when it prevents me from poitioning the bar full-depth into the slot.

[JPG]

The miter bar retaining washer will interfere(assuming it has not had the Reible double-d modification), but it will likely drop down sufficiently to align to the slot.

That places the miter gauge face at a 'non-vertical' angle. I am not familiar with the 520 rail, so I do not know if that will present a problem, but the top corner of the face is not machined from the top. I do know the table front edge is not a machined surface over the entire width(them bosses are, but they are inaccessible).

I doubt this will work well with a 505/510/520 table.


BTW There is no 'pitch' adjustment for the table. Neither does it matter.

[Hobbyman2]

I personally feel this has been a very productive thread , BuckeyeDennis you said it , ya have to check it before you can trust it , if it works for others then it is just one more trade secret for their arsenal .


I took several drafting classes,,spent 4 years as apprentice in the pattern shop , that was back when Iatola was messing around in the desert,,, we had 4 people who used the same saws all day long , can you imagine how long it would take to align a miter gage every time with out a quick way to do it?

One or two had the quick set gage but mostly used it for angles .

Spent many years in the filed as electrical technician & HVAC design ,,worked on everything from high rise buildings to craw spaces in mobile homes ,,,, .

Here is another one that will throw a wrench in the conversation ,,I know my table is square ,,,, I actually check and set my squares to the table top on my other saw ..

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It has never led me wrong.

My square will go all the way around the table and the miter gage and the corners all read square.

I seldom use my SS as a miter saw but I do re-saw some with it.

But ,,,,,like you said,,,,,, check and verify for accuracy .

[BuckeyeDennis]

The miter bar retaining washer will interfere(assuming it has not had the Reible double-d modification), but it will likely drop down sufficiently to align to the slot.

That places the miter gauge face at a 'non-vertical' angle. I am not familiar with the 520 rail, so I do not know if that will present a problem, but the top corner of the face is not machined from the top. I do know the table front edge is not a machined surface over the entire width(them bosses are, but they are inaccessible).

I doubt this will work well with a 505/510/520 table.


BTW There is no 'pitch' adjustment for the table. Neither does it matter.

Ah, but the table does control the "pitch" of the workpiece. It keeps it at zero.

Workpiece "pitch" angle matters if and only if the table is also tilted about the "roll" axis (for a bevel cut). In that situation, IF you clamped a (right rectangular prismatic) workpiece to a non-vertical miter-gauge face, such that the workpiece was not riding flat against the table, you would cut a compound angle. But I agree, if the miter gauge is used normally/properly, it's face need only be "reasonably" vertical.

I have one miter gauge on which the face is not even flat. It's slightly concave. This doesn't matter either, if the workpiece is long enough to span the entire face.

[JPG]

The miter bar retaining washer will interfere(assuming it has not had the Reible double-d modification), but it will likely drop down sufficiently to align to the slot.

That places the miter gauge face at a 'non-vertical' angle. I am not familiar with the 520 rail, so I do not know if that will present a problem, but the top corner of the face is not machined from the top. I do know the table front edge is not a machined surface over the entire width(them bosses are, but they are inaccessible).

I doubt this will work well with a 505/510/520 table.


BTW There is no 'pitch' adjustment for the table. Neither does it matter.

Ah, but the table does control the "pitch" of the workpiece. It keeps it at zero.

Workpiece "pitch" angle matters if and only if the table is also tilted about the "roll" axis (for a bevel cut). In that situation, IF you clamped a (right rectangular prismatic) workpiece to a non-vertical miter-gauge face, such that the workpiece was not riding flat against the table, you would cut a compound angle. But I agree, if the miter gauge is used normally/properly, it's face need only be "reasonably" vertical.

I have one miter gauge on which the face is not even flat. It's slightly concave. This doesn't matter either, if the workpiece is long enough to span the entire face.

YEP!

[Hobbyman2]

the tabletop itself controls both the "pitch" and "roll" angles

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May I add to this comment,,,,, that this is particularly true with the shopsmith or any machine where the cut is adjusted by the table , I would add to the comment on a stand alone saw the blade angle and table alignment is crucial as well , also all tables should be flat , I have seen tables that were warped or out of adjustment , that makes for a unsafe cutting operation and cuts that are not true..

Maybe tables could be a topic for a safety thread.