v120 face tilts when protactor rotated

[algale]

I have a Shopsmith edition Incra v120 miter gauge. At 90 degrees on the protractor, the face is perfectly perpendicular to the table.

FullSizeRender (2).jpg (103.73 KiB) Viewed 1707 times

If I rotate the protactor, the face is no longer perpendicular. Here it as at 45 degrees.

FullSizeRender(1).jpg (177.21 KiB) Viewed 1707 times

My Shopsmith miter gauge does not do this. Any ideas?

[reible]

I just went out to check mine. It doesn't have your issue. At this point I don't have any idea why that is happening.

Does it do that same thing when set to the other 45 degree setting?

Ed

[algale]

I just went out to check mine. It doesn't have your issue. At this point I don't have any idea why that is happening.

Does it do that same thing when set to the other 45 degree setting?

Ed

Hi Ed, yep, has the same issue at both 45 degree settings. I'll test a few more angles as well.

[Mike907]

Does the Miter Gauge face stay perpendicular to its own miter bar when rotated, and have you put a straightedge across your table?

Mike

[algale]

Good questions. I'll take a look.

Given that my standard Shopsmith miter gauge doesn't exhibit this problem, it isn't likely an issue with the table.

[JPG]

I would guess the miter gauge is pivoting on an axis that tilts(not vertical).

However your two pix show the square on opposite sides of the pivot.

A more revealing comparison would be positioning the square at the location in line with the pivot.(same location with all protractor angles).

[reible]

I'm now wondering if this issue could be happening if the miter bar is twisted in the miter slot and if it goes away once a piece is clamped down?

If you were to slip a narrow piece of wood on the table and clamp down on it with enough force to do cutting that load might bring things into alignment. The wood would have to be placed so you still had access to check the squareness to the table.

The other question is have you tried it on both miter slots and at different spots along the slot?

Ed

[algale]

Last night I took the gauge completely apart. It really has very few parts and none appeared to be damaged/bent/or defective.

I remembered that there is a vague reference in the instructions to using paper to shim the face of the gauge perpendicular to the table top. I probably would have glossed over this except there is a more specific discussion of this in the instructions to another Incra miter gauge I used to own and which required shimming.

When I got the v120, I remember checking and thinking no shims were necessary. What if anything has changed, I'm not sure, but last night I put some shims in place and think I may have resolved my problem. I am going to recheck tonight because I have a habit of seeing what I want to see when it gets very late.

[dusty]

I had to shim mine but when I was out-of-square it was in all positions. I'll be watching with great interest.

[algale]

Well, in the cold light of morning I have gone back and tested the now shimmed fence with my square and it seems to be square at 0 and at 45 degrees left and right.

I am dumbfounded because previously it seemed square at 0 without shimming but was leaning when rotated to 45 degrees.

Makes no sense to me whatsoever but it is what it is.