dynamic test of table saw blade alignment

[al ladd]

I just posted a video on what I think is the easiest method I've ever seen of accurately checking table saw blade alignment to saw's miter gauge grooves, especially for a person who hasn't purchased a special tool for the purpose, (but probably easiest for anyone.)

As I'm claiming a superlative for something novel (at least as far as I know), I'm leery I might be missing something, and so advising people to do something awful. If that's the case, I bet a few people here will tell me so!

Thanks for looking:https://www.youtube.com/watch?v=GawrKyyTB_0

[Doug Garson]

Seems like a valid way to ensure the blade is not misaligned. Since you cut from both sides of the blade, it ensures it is parallel. Well done.

[Andrew Hughes]

Why is there saw kerfs through your miter gage fence?

[Doug Garson]

I think they are called oops cuts.

[al ladd]

Why is there saw kerfs through your miter gage fence?


"I think they are called oops cuts." ----- I certainly don't remember whether I had an actual reason to make those cuts or whether they were accidents! Probably accidents.... (I can't think of a good reason now for why they'd have been intentional, --but I might have thought I had a good reason at the time!). I guess the clearest answer i can give you is I've had the miter gauge for several decades and have used it every day for thousands of different types of cuts. The kerfs really have no effect on the fence's usefulness, nor on the blade when the cuts were made. Because of them I did consider using a different miter gauge for the video, out of vanity, but I decided the gritty truth is best!

I realize most of the Youtube woodworkers present with pristine tools that seem to get used mostly for videos. Many of my tools are older than most of the YT woodworkers themselves, and have helped me earn a livelihood my entire adult life through actually making and selling things out of wood.

I've been considering swapping my Powermatic 66 for a Sawstop, but somehow it would feel a bit like leaving my spouse for a younger woman. I've made it this far without a table saw blade encounter, with hours of my fingers being so close to the blade the safety police would have me jailed for life. Not to say I still don't consider this particular swap. But, besides the infidelity, it would be so much work....

[George Yetka]

We all have oops marks, we just try and keep them off our hands. I got my new sawstop and 3 days after getting the saw I cut down the height of 3 drawers and hadnt realized kreg screws where peaking through. Now my saw has 8 racing stripes.

[Andrew Hughes]

I think they are called oops cuts.
Your too nice Doug. I believe they are called Appreciate marks. :)

[Bill Dufour]

I do not understand the geometry? Seems like the tiny width is too small to see any error. To my eye all it proves is the mitre gauge fence is at 90 degrees to the slot. If the blade was skewed by 10 degrees a through cut would still be at 90 wouldn't it?
Bill D

[Robert Hazelwood]

Bill, he isn't measuring the angle of the cut made on the stick. Just comparing the cut length at front of the blade and back. The method should work with the mitre fence at any angle, although that would make figuring the magnitude of any error more complicated.

This is just like the common method of resting a combination square in the slot and setting it until it touches a tooth at the front, then comparing with the back. He's just doing it with a piece of wood and with the saw running, and using a piece of scotch tape to gauge how far off from perfect it is.

[Bill Dufour]

For me the $18 horrible fright dial indicator is well worth the cost. Especially at 20% off. It is also useful for setting up jointers, planers, etc. You can probably find one cheaper online. I find used stuff like that on the bay is cheaper if it is metric. For most here metric is fine since your goal is to reduce the motion to zero not actually measure anything.
Last week I bought a slightly used bore gauge with a metric dial indicator. Cost was about 1/3 of a equilvilant inch unit. It is used by sweeping the bore to the lowest reading then pulling it out and using a micrometer to push it back to the same reading. Use any micrometer in any units.
Bill D