Alignment of Table Saw Blade, Slot and Fence using dial gauge and shop made fixtures

[Steven Woodward]

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 https://youtu.be/tOHy69VmNwk

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[Tom Bussey]

I know I am going against the norm and established way of doing things. But here it goes. If you take a piece of wood about 1 1/2 inches wide and cut a piece on using the miter gage moving to the back of the blade and listening as well as seeing what happens at the back of the blade. Switch to the other miter slot and repeat the operation. You will know which way the blade is off and then move the table accordingly and repeat the steps until they are both the same at the back of the blade.You will not be able to do any better. You are doing the checking under running load not static. They want to sell indicators and make you believe you need them and all the extra things that go with them.

The same is true with the fence. if you get saw dust off the back of the blade then you are pinching it and that can be dangerous and cause burning. if the other way the blade will want to cut straight and pull the wood away from the fence. Remember it is the back of the blade that lifts the wood up and back at you. Using a piece of plywood ( no stress in it ) cut the plywood so that the blade is engaged at the front and the back and then loosen your cutting and holding pressure. If standing to one side on should be able to take his hands off from the wood and it should sit there and not move. and then complete the cut and the cut lines should be as if there was no stopping. Some will say that the back should be away from the blade afew to .010 and the one selling that philosophy was also selling Forrest blades. And the piece to the left of the blade was about a 1/16th of an inch.

Again if the fence is away from the back of the blade the blade will want to pull the wood away from the fence and the board will not be exactly what you wanted. if the other wa then you will get a pinch and the board will get harder and harder to push and the back of the blade can lift it up and bang a kick back.

Is an indicator useful ,yes you can measure how much you are moving the table at the back of the blade. You will know how much you moved it in case it was moved to much or not enough.

You can disagree with me and spend a hundred dollars or so and still not get the results you are looking for.

[Bob Jones 5443]

This is what I value most about SMC: ideas and experience from across the spectrum.

While I have always approached table saw blade alignment more or less along the lines Tom describes, I can see that Steven has developed a keener sense of his machine through his foray into the dial caliper. Goodness knows I've gone "technical" with many woodworking operations. Don't get me started with sharpening (but my method works every time).

So rock on, gentlemen, and pursue your craft in the way that works best for you.

Steven, you could probably bring your instruments and fixtures to help someone who just bought a neglected used saw. I can say I would have benefited from someone with knowledge who could have helped me get my jointer and planer performing well a few years ago. I stumbled through lots of trial and error before they became reliable and repeatable. Now I take it on faith with gratitude that they work, but I don't remember how they got that way. If they ever go out, I'll be back to approximately Square Two.