Table alignment

[Ed in Tampa]

Nick in the thread on Main Table ribbing you gave a three part adjustment to the properly align the table.
In step C. Square the miter gauge slots to the axis of rotation in the sanding/sawing position.

You said, "Measure the distance between the disc and the table slot. Then turn the disc so the high spot is near the back and repeat. Position the table so both measurements are the same and the bill is still pinched in place. Tighten the bolts."

I need to understand what you meant by "the same".

As I explained in that thread that you may have missed is, I'm using a dail indicator. I believe one full revolution of the needle is .1 of an inch. The scale has 9 numbered segments which I think equal .01 of an inch and between each numbered seg is 9 other marks that I think equal .001 of an inch.

After playing with my table and trying to tighten it without moving anything I seem to only get my table to align so that there is a two mark difference between the front and back. I think that is .002 which is not very much and most of the time I can alter that just by slapping the table with my hand.

It that close enough or should I strive for "the same" meaning to me no difference in reading on a dail indicator.
Thanks for all of your help
Ed

[Nick]

Ed, I apologize for the poor directions. The engineers around here would beat me with a slide rule if they knew that I spec'd two measurements as being "the same." I should have written "within .005"."

The specific maximum allowable difference between the two measurements are determined by the diameter of your saw blade and the set of the teeth. By "set", I mean how far the teeth protrude sideways from the body or plate of the saw. For example, if you're working with a 10-inch-diameter carbide-tipped saw blade and the teeth are .125" (1/8") wide and the saw blade body is .100" thick, then the teeth protrude .0125" on each side. The set is .0125" (.013" is close enough for government work).

If the table is misaligned more than .013" across the 10" diameter of the saw blade, then the wood will rub on the saw body as it's fed past the blade. So if you have aligned the table to within .002" across the 12" diameter of the sanding disc, you're home free -- and then some.

With all good wishes,