Tools, Sharpening and Power Machinery - Table Saw Etiquette

Hello,
I am fairly new to woodworking and I ran into a problem recently that I thought someone might be able to answer.

I was cutting some painted board that i saved when changing my porch in order to re cycle them. But, I noticed that the table saw didn't like this very much, as it caught the paint in its teeth.

I cleaned the teeth off with a toothbrush and paint thinner and am thinking about going ahead and cut the rest and just clean up the teeth again later. Is there a problem with this that I don't know about?
thanks Joe

Shouldn't be; is this a carbide blade?

Lead paint? I've cut painted lumber on my table saw without that problem.

Good catch, cw; I was thinking more on the line of a non-carbide blade running a bit hotter and melting the old paint to the blade.

Yes, this is a carbide blade. I remember a friend saying to me that the manager of a community workshop would not let him cut varnished oak furniture ( ie pew benches) on the equipment because it would gum it up. But, mine simply would not cut very well at all with the paint on the teeth. But, what do I know?
Joe

Well, saw blades eventually will gum up to a certain extent regardless of what you're cutting. There are plenty of products to clean blades with.

"Well, saw blades eventually will gum up to a certain extent regardless of what you're cutting. There are plenty of products to clean blades with."

Yes, but this is not "eventually". It is after cutting a few boards. You guys have got me worried. Either I am imagining things or something really odd is happening with this saw blade. I was going to give up cutting these things altogether because of this problem. I looked on the saw and it says carbide. I can see the paint on the teeth and scrape it off with a knife and the toothbrush.

I tell you this was getting so bad ( there would even be smoke when i tried to run the boards through the saw!) that I devised a plan to just cut below the paint and then try to split the boards, in order to save them. this seemed a little too dedicated, though.

Joe

Just a thought. Could the blade simply be old, worn out and dull? How would you tell with one of these?
Joe

Saw the boards with the painted side down.

Rip a piece of PT straight from a big box. If it'll cut that without binding it's sharp.

It may be that your blade is just old, tired and dull. If it's carbide tipped you can get it sharpened.

thanks guys,

I will turn the piece upside down to see how it does. Also, it does seem to cut regular lumber without binding--once I clean the paint off the teeth. Maybe I will just take it in to get it sharpenned, anyway. I bought this saw second hand and it may have had a good deal of use already. did i not hear that you could just take the old blade in and exchange it for a new one? Where would I take it to get it sharpenned?

thanks Joe

Do the boards have just a single coat of paint or do they have a big buildup of multiple coats?

"Do the boards have just a single coat of paint or do they have a big buildup of multiple coats?"

Well, there are at least a couple of coats. I don't know about a big buildup. But, this is porch paint, which in itself, I think, is quite thick. All in all, about three coats. But, like i say, this is fairly thick paint.

Joe

Usually when my table saw starts to struggle I know it's time to either sharpen the blade or replace it. I don't recall noticing any problems because of paint. I would think it is either the blade or the saw is under powered - I'd start with a new blade ;)

I'm fortunate to have a machine shop that sharpens saw blades only a mile or so from my house. They charge around$5-$10 depending on the number of teeth. It's amazing the difference sharpening makes.

Check out the yellow pages for your area.

Is it possible that you have a blade with a large number of teeth more suitable for crosscutting rather than ripping?

If you don't need a smooth edge a 24 tooth ripping blade would not heat the paint which causes the gumming.

"s it possible that you have a blade with a large number of teeth more suitable for crosscutting rather than ripping?

If you don't need a smooth edge a 24 tooth ripping blade would not heat the paint which causes the gumming.
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Hello GeorgeH,

I notice that you are a "SuperModerator" I don't know exactly what that means but it must mean that you know a good deal about this kind of thing. And since you mention that there can be a heating going on here that causes gumming. That makes me feel a little better, since it confirms that I may not be imagining all of this ( or misunderstanding what is going on). I am not sure of the number of teeth. I have a very fine blade in my drawer which I bought from Sears on sale. I have hesitated to use it, except when I get to fine work ( which I may be a distance from at the moment) and so I did not want to take it out.

If I understand you correctly, sharpenning may not be the answer. It could be too fine a blade that gets gummed up by the paint. And the solution may then be not so fine a blade. I am sure that with the help of everyone here I will get out of this quagmire and will be cutting again,\

thanks Joeh

Greg,

Sorry about the "George", I meant Greg.
Joe

SuperModerator means he wears one of those cool uniforms under his street clothes with a big "S" on it. :D

Also, he's very knowledgeable.

Could be a combination of things, i.e. too many teeth, not sharp enough, many layers of paint, and (to add one more wrinkle) maybe the paint is oil-based. A paint guy will have to correct me because I've never given it much thought, but possibly oil-based paint would be more susceptible to gumming up a blade than latex?

Dry oil base paint is hard and brittle, latex tends to be softer and a little pliable. I would think dry latex would pose more of a problem than dry oil base but don't know for sure.

I've never had a problem with ripping boards painted with either. If not mistaken I run a 40 tooth blade on my table saw.

Thanks TG but Super Moderator is really what happens when you do something dumb like putting up your hand when someone was looking for a volunteer rather than being head down looking down at your shoes!

In reality it just means that they give you a few more buttons to click to help keep things running smoothly, it is not that you are a saw blade expert. :)


A coarser blade may help but it might not eliminate the problem totally.
It would be similar to what I experience when trimming laminate.
I need to sometimes stop and clean the router bit of burning adhesive before it dulls.

Try something like this (http://www.doityourself.com/invt/u341081).

Just a thought, since the blade is gumming up after only a few boards, is it possible the blade is in the saw backwards. It will not cut well, and will burn more than it will cut, sort of like what you are describing. But all the other suggestions are very good, so let us know how it goes.

Where are the "Mythbusters" when you need them? :D

They could make a show out of this.

How high do you have your blade set at? If it's too high, your teeth arent cutting the material at a good rate and the body of the blade is rubbing against the material...!

Hello again,

thanks for the good replies. I will get a chance to to into the garage tomorrow and test it out. But, I don't think the blade is on backwards and I raise the blade just above the level of the piece i need to cut, so I don't think those things are the problem. I had been wondering whether it might be that the belt is slipping on the motor. I will check it all out and let you know if i can figure out the problem. Maybe I just need to sharpen it up. We'll see

Joe

And for the grande Finale....It was dull! I put another old blade that I had in and it worked wonderfully. It should have been the first thing that I thought about, I suppose, but maybe I was put off track by that idea of paint dulling the blade, that I;d heard. It is really amazing, though, how dullness can really impede cutting!
thanks for the support and help

Joe

Glad it worked out..
Uh, yes.... a dull blade will impeed performance.
Amazing isnt it!!!

More than once I have been pleasantly suprised at how much better the new blade cut than the old one it replaced :D ;)

Yep .. - thats the whole idea.
Skimp on the blade..and you skimp on the work..!
Not my cup of tea!

Like the old story on how to boil a frog. The blade gets dull slowly over time so you get used to it.:coffee:

Just a followup question, if I may. I took the blade down to the store today. The guy said that it would cost twenty four dollars to sharpen it, I believe. I know that someone on this board mentionned that they can buy new blades for twenty four dollars. Am I better to get it sharpened or buy a new one? The blade is really quite thick and hefty. More so than the other blade that I found around and put in. Would that mean that it would be worth shapenning? I do have a rather expensive fine wood working blade that I have never used. I believe it was supposed to cost over one hundred dollars and I got it on a big sale at Sears.

Joe

A little info on saw blades.

The thicker the blade (kerf) the more power it takes to turn it when cutting.

When ripping wood, use a coarser (40 tooth) blade.
When crosscutting, use a finer (60-80-100) tooth blade.

I purchased one unmarked Irwin blade on E-bay and am very happy with it. Don't buy the Chinese blades. They are cheap, but they are cheap junk.

Im all for sharpening when reasonable.
Imho, $20. to sharpen an old blade VS $24. for a new one....Id buy a new one. - so long its of the same genre.
Depending on how often you use the saw and that kind of blade would dictate whether you want or need another (2). If so, then sharpen the old one for back-up.
That's what I would do..and have done...!!