Sharpening table saw blades

…or mitre saw blades etc.
Any thing I need to know more than just file at same angle as tooth?
thanks

1 Like

I don’t know anything about this, but I’ll speak up just because nobody else will.

I’m pretty sure there’s more to sharpening table saw or miter saw blades than just getting the angle right. For one thing, there are about nine different tooth grinds available. I think the simplest is just flat-top, where all the teeth are like chisels. Even then, the teeth don’t just have to have the same cutting angle. They must also cut to the same depth. You can set them to the same depth by hand turning the blade backwards in the saw against a whetstone to make a tiny flat on the crest of each tooth, then grinding the angle just enough to remove the flat.

But that’s just a flat top grind, where all the teeth are identical. Alternating bevel teeth have alternating skewed angles. I can’t imagine how you set them all to cut to the same depth. And then you have to grind the teeth to the right angle not just front to back, but side to side. And alternate them.

And there are other tooth configurations where the tooth are grouped in threes or fours, each different. Then there are triple chip teeth where they don’t actually cut to the same depth, intentionally.

And by the way, if the blade has carbide teeth, it has to be sharpened with diamond tools. (And if it doesn’t, then it might not be a very good saw blade, and not worth resharpening.)

So that’s why I don’t actually know anybody who sharpens their own saw blades. They send them off to be resharpened, or just toss them out.

That’s all I can tell you! Best of luck!

EDIT: And I forgot, here are some of the different tooth configurations, with drawings.

https://www.toolstoday.com/t-sawbladeterminology

1 Like

I take my blades to a local sharpening company that has a CNC saw blade sharpening machine. They charge just $15 for a 50tooth blade. They can also replace carbide teeth for a few bucks per tooth.

2 Likes

A good quality table or miter saw or even circular saw blade is going to have some form of a Carbide tooth. Those usually have to be ground with a grinding wheel - a file won’t touch it. It is harder than steel technically so unless you are using something like a diamond impregnated file or one made of Alumina Ceramic then a normal file won’t do much.

Second yes matching the angles of the tooth are the basic idea but when you sharpen them remember that there is multiple angles. Example the sides of my table saw blade have a slight angle, the face angle is one thing and the top is also not on 90 to the tooth face. (diablo TCG). So it gets complicated fast.

Now if you are using a basic point tooth blade then yes it’s a much easier process and usually those aren’t carbide. I don’t have any like that anymore - haven’t used a basic point tooth blade in years.

Like said above I would look for a local sharpening place and failng all that I would balance the cost of a new blade. I had some issues with my mitre saw blade cutting popular recently and I cleaned my blade. Just cleaning. Worked like new - turns out it had some sap gunk in there from cutting some pine from my last project.

Good Luck.

2 Likes

While you do need a proper grinding wheel, the part of the tooth that is ground isn’t the back bevel (top or the tooth when it’s on a table saw saw) its actually the face (the part that is almost vertical when mounted on a table saw) .
BUT, filing by hand is not a good idea, because if you do change the angle by even a degree, it will affect the way the saw cuts and can cause it to pull the cut or it can cause premature wear due to heat buildup. If uneven it can also cause the saw to cut only on the longest teeth, as grinding the face affects the height of each tooth.

Background is that I have a Foley saw filer and I also grind moulder knives for our mill

2 Likes

Thanks all. I looked again and found the a large part of the problem (almost always getting smoke) was a build up of resins or whatever on every tooth.
I wire brushed it all off and it cuts better.

But I like the advice to get a new one… a good one. I just need one blade…a combo. I’m no pro.

Thanks to all who replied: VERY helpful!

1 Like

Persoanlly I’m not a fan of combo blades on a miter saw. Combo blades have the wider gullets to help with long rip cuts - miter saws don’t do that.

I do run a combo in my table saw since I do some of each cut but mostly rip cuts. on the table saw.

Mitre saw has either an 80 tooth for fine cuts or a 50 tooth for pressure treat outdoor lumber. And if I was to do something really odd might get a custom blade for that too

1 Like

Thanks. I’m about to do a greenhouse so that is helpful.

combo on table saw sounds about right

1 Like

I run Diablo carbide blades on all my saws. I have a Smith diamond sharpener in my tool trailer, but I rarely have to use it. I take my blades off the saws 1-2 times a month depending on their usage. I’ll grab a big Tupperware tub thing that the old lady had for foot baths until I commandeered it. I grab a nylon brush, splash a little Simple Green in the tub and run some hot water, enough to cover the blade. Let it sit for 5 minutes and go to town with the brush. Most of the reason your blade dulls is because of the buildup on the carbide or you hit a nail or screw. Scrub the blades, towel them off with a terry towel and spray a little BladeCote on there. Good to go without necessarily having to sharpen a thing. If I run into a nick here and there, I throw a little mineral oil on the diamond stone and hand sharpen the problem tooth. It’s worked out so far.