How Long Should a Good Saw Blade Last?

[Pat Germain]

I recently bought a Forrest WWII blade for my table saw. I'm very pleased with the cuts, but wondering how long it should last before it requires sharpening. Today I made some cuts in 8/4" hard maple and my saw was seriously bogging down. Is it possible the blade just needs a good cleaning, or am I just kidding myself and in dyre need of a sharpening?

Granted, I've been doing some heavy duty cutting, but I was hoping to get more life than this out of it. Since I bought the blade, I've made three cutting boards from 8/4" hard maple and walnut, cut a few pieces of 3/4" birch ply and cut some pine here and there. How much use should I expect from a WWII before it's dull?

[Matt Meiser]

Have you cleaned it? We had a talk by a pro sharpener at our woodworking club and he said that many of the blades he got in for sharpening didn't need anything more than a cleaning. Mine hasn't been sharpened in a few years and I've just started noticing a decrease in cut quality. I just picked up a backup blade tonight so that I can send it in for sharpening. I've cut a ton of oak, plywoods, maple, and various other things with it before getting to this point.

[Pat Germain]

Not yet, Matt. I don't have any kerosene or Simple Green in the shop. I called LOML while she was at my local Target, but they didn't have any Simple Green. I plan to find some Simple Green tomorrow and give the blade a good cleaning.

I need to tell LOML whether I'm done cutting until I can get a sharpening, or if there's a good chance cleaning will help. From your post, Matt, I get the impression a gunky blade can behave like a dull blade. Does is make that much of a difference? I was under the impression a gunky blade was just more likely to cause burning. If your blade hasn't been sharpened in a few years, I should have a few more years of use. My blade is only a few months old.

[Dan Barr]

yup, me too

i clean my whenever i see the burn marks starting to show up on any cuts. other than that, i dont think i'll need any sharpening for quite a while.

also, its just like a brand new blade everytime i clean it. wood just glides right through.

v/r

dan

[Gary Keedwell]

For more years then I care to admit...I used oven cleaner. A few years ago I started to use Formula 409. Works great. Spray it on...wait a couple of minutes and wipe off with paper towel. Sometimes I'll scrub with an old tooth brush. I change my blade frequently because I'm one of those guys that likes to use a dedicated blade for each operation. Only takes a few minutes to clean while you have it off the saw.
Gary

[patrick anderson]

If this makes any difference to your thinking I picked up a almost new CMT crosscut blade (80 tooth or something). Anyway, when I put it on it was like the proverbial slicing through butter until I stupidly tried to take a thin rip off a 4" tall piece with the blade at full height. It smoked a bit and popped a fuse and I swear it doesn't cut the same. I think it needs a bloody good clean as I can see yellow crap on the teeth

[Pat Germain]

I've seen many threads about what to use to clean a blade. Oven cleaner seems to scare lot of folks, but hey, if it works, it works. I recall seeing a post from a Forrest rep who recommended kerosene, but I'd rather not have a container of fuel sitting around just for blade cleaning. I guess if I get a kerosene heater, it will be more practical.

It seems the most common consensus is Simple Green and kerosene are the safest options. I understand oven cleaner can compromise the carbide bond.

Just to be clear, you guys are telling me if my blade needs a good cleaning, it can behave as if it's dull. Correct?

[Dan Barr]

Yep.

clean it up good with formula 409 and you'll be back to new.

v/r

dan

[Dan Barr]

Yes,

it will give burn marks and seem slower than when clean. if you look at the teeth you'll probably see plenty of resin on the sides and backs of the teeth. just strip that off nice and clean and you'll be back to sawdust.

v/r

dan

[Pat Germain]

Thanks, Dan, and everyone else. I'll go ahead and clean the blade with 409. It's probably pretty gunked up.

My $20 contribution to SMC just paid for itself. I hope anyone else who can contribute will do so. I sure need this forum to keep going! :)

[Bruce Wrenn]

I recently bought a Forrest WWII blade for my table saw. I'm very pleased with the cuts, but wondering how long it should last before it requires sharpening. Today I made some cuts in 8/4" hard maple and my saw was seriously bogging down. Is it possible the blade just needs a good cleaning, or am I just kidding myself and in dyre need of a sharpening?

Granted, I've been doing some heavy duty cutting, but I was hoping to get more life than this out of it. Since I bought the blade, I've made three cutting boards from 8/4" hard maple and walnut, cut a few pieces of 3/4" birch ply and cut some pine here and there. How much use should I expect from a WWII before it's dull?Two magic words- 8/4 and maple. I would suggest that you use a dedicated ripping blade with about 24-30 teeth for this. I also concur with cleaning your blade regularly. I have blades that are over ten years old and have cut thousands of feet of 3/4 birch ply. One day they will need sharpening, not now though.

[Jared Cuneo]

I've tried a few different cleaners and I tell you, the best by miles is the CMT blade cleaner. I spray it on, and less then 30 seconds, the gunk wipes right off, and it has a nice smell too :)

Oh, and it comes in a handy spray bottle.....you have to use VERY little.....I've cleaned my blade 5 times and it hasnt even made a dent in the bottle....

http://www.highlandwoodworking.com/index.asp?PageAction=VIEWPROD&ProdID=1288

Woodcraft carries it and I'm sure many others....

JC

[glenn bradley]

Blade cleaner review:
http://www.empiremfg.com/products/industrial/bladesaver/B&B%20cleaners2.pdf

[Andrew Nemeth]

I second CMTs cleaner. The product works great and it's non-toxic. I bought some of it when I was picking up a second WWII blade at Woodcraft to use as a backup before I send my other WWII out for sharpening and a tooth repair. Well, I got home cleaned my old blade and it worked so well I dug out some older freud blades stuck in a drawer. They cleaned up so well, and cut so cleanly, that I returned the second WWII and I now have two backup Freud blades to use while I get my Forest fixed. I bet the pitch buildup could cause enough friction to bog down a motor IMHO.

[Lance Norris]

Today I made some cuts in 8/4" hard maple and my saw was seriously bogging down.

How much horsepower are we talking about? If you have less than 3 hp, your saw is going to struggle some in 2" hard maple

[Pat Germain]

How much horsepower are we talking about? If you have less than 3 hp, your saw is going to struggle some in 2" hard maple

My TS is just an old, hot-rodded Sears contractor saw, but when I first started cutting the maple, it cut pretty well.

[Gary Keedwell]

Blade cleaner review:
http://www.empiremfg.com/products/industrial/bladesaver/B&B%20cleaners2.pdf
I don't know if a review that may favor retail specialty products is being fair. Alot of those products sold in retail specialty stores are just household products packaged to appeal to the woodworker.
The more I got into finishing the more deceit I have seen. People buy a bottle of stuff that says "tung Oil Finish" and there isn't any tung oil in it.How about "wiping Poly"? It is just POly that has been diluted with mineral spirits so the consumer is really spending big money for cheap paint thinner.
I have read numerous "reviews" from real woodworkers who clean their own blades using household products that are very happy. I thought for many years that I needed something "strong" so I used oven cleaner. I then read all these testimonials about Formula 409 ( I'm sure that there are other products that will also work) and a light brushing with a toothbrush and I can tell you it cleans my blades sparkling clean. That's my two cents and I'm sticking with it.:)
Gary

[Jim Becker]

In addition to keeping the blade clean, you'll need a much slower feed rate when cutting thicker material with a lower-powered saw. If you keep the bite within its capabilities, it will do the job nicely. But you'll also need a nice even feed rate, too, to avoid burning. No stopping if you can avoid it.

[Pat Germain]

^^ Thanks, Jim. I was using that technique and it was working pretty well until yesterday.

A new, more powerful TS is in my future, but I want to get a very nice example. It's going to take awhile to get the proper budget. Then, as usual, I'll be seeking the advice of the SMC forum.

[David Weaver]

It'll be interesting to hear your opinion after you clean the blade. I have been using a WWII TK for about a year now - first in a contractor saw, and now in a hybrid. If it's sharp and clean, you should still be fine cutting 2" maple as long as you don't let it stall in a cut - I haven't really had any trouble with anything - just can ram it through a 1.75 hp saw like you can a 5 hp saw.

Buddy of mine has been using a WWII TK in a 5 hp PM66 for probably 5 or 6 years and hasn't had his sharpened. If you're just using it on weekends as a hobbyist, it should last a really long time before it needs sharpened.

[Paul Girouard]

I've used oven cleaner for years aslo all the shops I've worked in used oven cleaner. Spray on , let it sit 2 or 3 minutes wipe off , sometimes a lil scot brite on stubborn spots.

With a under powered saw clean often and I'd wax the blade , the table and fence as well before the next run.

Feed rate and like Jim (Norm):D said no stopping if possible.

You'll be clean off the burns with a planer / power or jack type , anyway right?

[Paul Girouard]

I have blades that are over ten years old and have cut thousands of feet of 3/4 birch ply. One day they will need sharpening, not now though.




I think if this is true and you send out one of those blades to be sharpened you'll find a great difference in the cutting process.

The glue in plywood can be more abrasive that the wood used for the lams .

Send one out and give it a try , you may just be "used" / accustomed to dull blades and are working yourself and your saw to hard;)

[scott spencer]

...Just to be clear, you guys are telling me if my blade needs a good cleaning, it can behave as if it's dull. Correct?

Absolutely, and it can also lead to premature dulling by causing excess heat. You have something in your house that's capable of cleaning your blade well....Goo Gone, 409, Totally Awesome, Dawn w/water, TSP, Fantastic...any degreaser, citrus cleaner, etc., will work. Spray it on, hit it with a stiff brass or nylon brush...soak it for a few minutes if it's really stubborn.

The actual edge life depends on a lot of things...cleaning frequency, material thickness and density, moisture content, flatness, saw power, feedrate, saw alignment, etc. Hard maple is among the tougher woods I've encountered, and 8/4" is pushing the limits for the 40T WWII, especially with a smallish motor that may bog more. 40 teeth is a lot to have buried in that much wood and can cause excess heat compared to a 24T ripper or 30T WWII, which in turn dulls faster. There are some decent $30 24T TK rippers that'll have an easier time with 8/4" hard maple, and will help preserve the edge of your WWII. (Holbren's now got an Amana AGE MD10-240TB (http://www.holbren.com/product.php?productid=3524&cat=0&page=1) in that range, and there's a Freud LU87 (http://www.amazon.com/Freud-LU87R010-10-Inch-Ripping-PermaShield/dp/B0000225UH/ref=sr_1_2?ie=UTF8&s=hi&qid=1197823947&sr=1-2), a DW7124PT (http://www.amazon.com/DeWalt-DW7124PT-10-Inch-Ripping-8-Inch/dp/B000HCVN5C/ref=sr_1_1?ie=UTF8&s=hi&qid=1197823991&sr=1-1), and Leitz made Irwin Woodworking ripper thru Mike Jackson (http://www.forums.woodnet.net/ubbthreads/showflat.php?Cat=&Board=UBB4&Number=3314621&fpart=&PHPSESSID=))

[Matt Meiser]

There's an article on this very topic in the latest Fine Woodworking. As I understand, the pitch buildup on the blade teeth physically hinders the cutting, is corrosive to the binder in the carbide, and as Scott said, creates excessive heat. So yeah, dirty is bad :D.

After the presentation at our club meeting, I cleaned my miter saw blade which I figured needed sharpening. It cut like new. I did finally get it sharpened about 1-1/2 years later. The blade that came with my MS also cut pretty respectably after cleaning. I'd used it for cutting a lot of PVC (duct work and PVC outdoor trim) and it was pretty well coated in stringy PVC. The cleaner took it right off and cuts in construction lumber were very respectable.

Now any time I notice buildup on my blades and router bits, I clean them. I keep a bottle of the Boeshield (T-9?) cleaner and a brass bristled brush right by the sink. That's the only cleaner I've tried and it works well for me so I haven't tried anything else. The brass is safe for the carbide according to the guy who did our talk. I spray down both sides of the blade, let it sit about 2 minutes, then go over the entire blade with the brass brush to remove anything stubborn. After rinsining with hot water and wiping it dry I'm back in business. BTW, cleaning will quickly remove any fancy printing on the blades.

[Todd Jensen]

To take the burden off the blade, when I'm cutting thick or hard woods(or both), either on the TS or the slider, if I notice any bogging I'll make multiple shallow passes. With a good blade I still get good clean cuts in the end, and I'm not burning up the blade, wood, or motor.

[Cliff Rohrabacher]

Sometimes cleaning a blade makes all the difference in the world.


How long a good blade lasts is often simply a matter of what you do with it. Cut wood with lots of silica and it won't last so long between grindings. Or if you are like me you can drop a 5 pound forged Armstrong C clamp on you blade the very day you first mounted it and spun it up. That makes it go really fast.

[Mark Berenbrok]

I use mineral spirits, an old toothbrush, and one of those wide plastic basins for changing your car oil. Let it soak for an hour or two and use the toothbrush.

[Pat Germain]

I cleaned my blade this morning with some 409 and a scrub brush. It really did make a big difference, but I was still getting some bogging about halfway through cuts.

I recently aligned my fence to the mitre slot. Over the last few days I put the fence against the blade several times and it all appeared to line up nicely. Still, I decided to try realigning the blade. When I started to loosen the trunion bolts, boy did I get a surprise. All six bolts were little more than finger tight! It's been awhile since I messed with the trunion. Apparently, the bolts have been vibrating loose, or something.

After the trunion was loose, I clamped a piece of planed oak between the blade and the fence then tightened up the bolts good and snug. Of course, this made a big difference.

Between cleaning the blade, realigning the trunion, and tightening the bolts up tight, my saw is cutting MUCH better. It's still no MiniMax, but it's getting the job done. I think the trunion was actually moving halway through my cuts. :rolleyes: I've got some Loc-Tite somewhere in my shop. I think I'm going to apply it to the trunion bolts.

Thanks again for the input, everyone. I hope someone out there can learn from my biscuit-head experiences. :)

[CPeter James]

Pat check out this link. It is an article that I wrote a couple of years ago for the "Old Saw", the newsletter of the Guild of New Hampshire Woodworkers.

http://home.metrocast.net/~cpjvkj/tstuneup.htm

www.gnhw.org

CPeter

[Howard Acheson]

Your problem is as Bruce wrote. A 40 tooth general purpose blade like the WWII is not intended for ripping wood above 3/4" to 1". For hard woods that easily burn like Maple you should be using a 24 tooth dedicated rip blade.

If you contact Forrest they will tell you to use either their 30 tooth or 20 tooth blade.

[Jared Cuneo]

I see a lot of posts describing letting solvents soak, scrubbing with brushes, etc, and I have to reiterate as a public service in my opinion.

I have nothing to gain by pimping CMT blade cleaner, but I tell you that this stuff works normally in less than 1 minute of soaking (and by soaking I mean laying the blade on a paper towel and spraying, then waiting a minute) and wipes off with a paper towel with NO scrubbing required.

I cut pine, maple, cherry, sapele, and get my blades pretty gunky.....trust me on this and stop wasting time scrubbing and waiting around.....get the CMT cleaner.....

JC

[Dan Barr]

I'll try it out myself.

thanks,

dan

[Pat Germain]

I'll check out that article. Thanks.

As for the blade, I guess I should use a dedicated ripping blade with fewer teeth. In fact, I'm pretty sue I've got one laying around the shop unused somewhere

I was ripping some very thin pieces; down to 1/32". I thought the WWII would give me a smoother cut since I can't use the jointer on such thin material. I'll give the ripping blade a try and see what happens.

Boy, the more I learn the more I learn how much I have to learn.

[Bruce Wrenn]

I think if this is true and you send out one of those blades to be sharpened you'll find a great difference in the cutting process.

The glue in plywood can be more abrasive that the wood used for the lams .

Send one out and give it a try , you may just be "used" / accustomed to dull blades and are working yourself and your saw to hard;)I have several newer blades including a couple of Forrest WWII's, Freud LU84R's, Delta/ DeWalt 7657's. All of these are in either new or new condition. The old DeWalt triple tooth still out cuts them. The old DeWalt cuts like butter and leaves a surface that I don't even think about touching with sand paper. Better than what my Forrest WWII's give.

[Dan Barr]

Boy, the more I learn the more I learn how much I have to learn.


I second that emphatically!

same here and then some.

v/r

dan

[Chuck Burns]

If you contact Forrest they will tell you to use either their 30 tooth or 20 tooth blade.

I've been cogitating on getting that 20T WW from Forrest. Has anybody tried it, or the 30 tooth?

[Dan Barr]

Well, Jared

I got some CMT blade and bit cleaner and YES, its all its cracked up to be.

I sprayed it on, waited about 5 minutes, and presto! the gunk wiped off effortlessly. A lot better than 409, mineral spirits or kerosene. NO SCRUBBING or WIRE BRUSH involved.

It was $11.90 at my woodcraft and i think more than worth it. it only takes a few squirts on each side to get all the teeth.

Thanks Jared, :)

v/r

dan