Saw Blade run-out

[Robert Wimmer]

<!-- / message -->Have a new dial indicator and , in using it to check for runout/wobble of my sawblade found the runout/wobble to be considerably more than I thought it should be. Any idea what an acceptable runout/wobblefor a sawblade would be? images/buttons/edit.gif (editpost.php?do=editpost&p=126938)

[Scott Parks]

I dont know what is acceptable, but if it helps, my Grizzly Cabinet Saw with a Forrest WW2 blade runs out at .0015". (half the thickness of a dollar bill)

[Jim Becker]

Robert, be sure you are testing with the same tooth at either end of the travel. Do not switch teeth between measurments as there is always slight variation. Also put your dial indicator on the blade steel just under the carbide, not the carbide tip since there can be slight variations there. Once you make that measurement you should also check the runout of the "permanent" washer on the arbor with the blade removed. Runout on the arbor can be amplified out at the saw blade tip and it's important to determine "where" the runout really is...

[Hoa Dinh]

... be sure you are testing with the same tooth at either end of the travel....

No Jim. That would not be measuring total runout. The way I measure it on my saw is to zero in at a point just below the gullet of the blade, then rotate the blade by hand and record the movement of the indicator.

Mine is about 0.003" total runout. I don't know what the acceptable value is.

One way to minimize total runout is to vary the relative position of the blade with the arbor, say, 1/8 turn at a time, then select the best position, mark it and make sure always put the blade in that position.

[Jim Becker]

No Jim. That would not be measuring total runout. The way I measure it on my saw is to zero in at a point just below the gullet of the blade, then rotate the blade by hand and record the movement of the indicator.Good point, Hoa...you are absolutely correct. I was mixing up alignment with runout measurement. But I still suggest checking the arbor, too, to determine if it's the blade or the arbor that is "out"...or both.

[Robert Wimmer]

Just got my Woodworkers Journal in the mail and found that a reader had submitted the same question. Found it interesting that they quote an Aaron Einstein of Amana Tool as saying "the blade must be flat, flat, flat." He is also quoted as saying that Amana's maximum acceptable tolerance in a 10" blade is .002 Wow. None of my blades are that flat, although I don't have an Amana blade. I wonder if, in use, a blade can be thrown 'out-of-round.':confused: