Miter Gauge Moves While Tightening

JPG · Post by **JPG** » Sun Jan 15, 2012 6:23 pm

algale wrote: A different experiment, and one that has no potential to damage anyone's gauge, is for folks still following this thread to remove one washer from their gauge (if they have a two washer variety) and see if this results in movement of the protractor/fence when tightening down the knob (without applying lateral pressure to the knob).

I did not mean to lean on it so hard as to deform it!

I did try it with no washer and there is no discernible movement. I did that away from any stop.

I slipped a shim under the knob and the outer segment surface and that did cause the segment to move clockwise. Tried shimming the inner segment, and is was more reluctant to move, but did so counter-clockwise.

I have to conclude the outer segment has more surface area to contribute the this undesired movement.

So if the double washer helps, so be it and we have a 'work-around'.

I be adding a second washer to those I have which already do not. Why tempt fate?;)

robinson46176 · Post by **robinson46176** » Sun Mar 25, 2012 7:05 pm

I don't recall ever having that problem with a miter gauge but then again maybe I just did something to compensate without really thinking about it much.
On several kinds of machinery there are adjusting points with slotted holes. Sometimes there will be a double washer but the one against the main surface is of a softer material sometimes even like brake lining material so that it grips the surface tightly and the nut slides against a harder outer washer as it turns.

The best way to describe the function of a second washer is thinking of the two of them as a thrust bearing.
There a huge number of different sizes and types of thrust bearings. Here is one simple style.
[ATTACH]16787[/ATTACH]

If you have a serious problem with a miter gauge moving maybe you could replace the washers with an actual thrust bearing of the proper size.
I first encountered thrust bearings at about age 11 rebuilding king-pin bearings (2 bushings and one thrust bearing per side) on cars and trucks. That is also where I first learned to use reamers.

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