# Precise Alignment of Table Saw Blade with Slot and Fence using only a dial gauge and simple shop made fixtures. Demonstrated on SawStop



## StevenWoodward (Aug 14, 2020)

Inspired by the book: “Shop Machines” by John White, I found that I could get excellent results with shop made fixtures. The only expensive thing to purchase is a good dial indicator.

Blade alignment on a table saw should be checked at three blade positions: 1) vertical at maximum height; 2) vertical at minimum height; 3) bevel 45 degrees at maximum height.

Some table saws, such as SawStop ICS, have separate adjustment for each of these alignments, but even on a saw without separate adjustments it is good to know what the alignment errors are. 

Most instructions for alignment say to measure off of the blade. A better approach is to replace the blade with a rigid arm. I used 1/2 inch phenolic for the arm. An arm has two advantages, over a blade: 1) deviations on the dial gauge are amplified, which gives a better indication of the alignment error; 2) when the blade is at minimum height the arm still projects above the table so a standard dial gauge can still be used, whereas with a blade, a special vertical dial gauge would be required.

Photos below, Video here


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## Steve Neul (Sep 2, 2011)

I've been around woodworking equipment for almost 50 years and have never needed more than a tape measure to align them.


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## TomCT2 (May 16, 2014)

rather a bit overdone. 
setup the dial indicator on the slot - not the fence.
find a neutral spot on the blade (i.e. constant distance, eliminate runout of the blade)
mark the spot on the blade.
measure front and back at the same spot on the blade (rotate blade by hand)


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## Tool Agnostic (Aug 13, 2017)

I like using a dial indicator to check blade alignment with the miter slots. I like the ease of use, speed, and accuracy (not really necessary) compared with a combination square.

I designed a simple jig with a lap joint and a "compression fitting." You tighten it enough so that the jig is snug in the miter slot, but can still move along its length. It works well. Loosen the screw, and you can fold it up into a compact stick shape. The dial indicator is easily attached or removed for storage and protection.


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## Dave McCann (Jun 21, 2020)

Tool Agnostic said:


> I like using a dial indicator to check blade alignment with the miter slots. I like the ease of use, speed, and accuracy (not really necessary) compared with a combination square.
> 
> I designed a simple jig with a lap joint and a "compression fitting." You tighten it enough so that the jig is snug in the miter slot, but can still move along its length. It works well. Loosen the screw, and you can fold it up into a compact stick shape. The dial indicator is easily attached or removed for storage and protection.
> 
> ...


Using a spring loaded "ball detent" in the piece that goes in the miter slot, also works well to keep the slider registered against one face of the miter slot.


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## Tool Agnostic (Aug 13, 2017)

Dave McCann said:


> Using a spring loaded "ball detent" in the piece that goes in the miter slot, also works well to keep the slider registered against one face of the miter slot.


Very true, but those thin maple triangular cut-offs from another project had been laying around for six months, and I had been scratching my head all that time, wondering how I might use them. "Firewood" was not an option.


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