# cutting plywood with a bandsaw.



## JuniorJoiner (Dec 24, 2008)

I have always heard not to cut plywood on the bandsaw, and I listened until yesterday.

I had cause to make one 12" long rip cut to trim a jig , it was all glued together and had a router attached so I couldn't use the tablesaw. I cut glued up laminations all the time with the bandsaw, so I thought it couldn't do that much damage.

Well, one cut, and the blade is became too dull for me to consider safe to work with. It was less that 1 hr use before i made the cut, and would have been considered good for three times more use, until it saw plywood.

What I would like to know is, what glue they use in plywood that destroys bandsaw blades like that?

BTW. it was 1/2 inch baltic birch(the good stuff, not the cheap crap).


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## Pimzedd (Jan 22, 2007)

Cut plywood for over 40 years with a bandsaw in the high school shop classes I taught; mostly 3/4 in. AC grade fir and some 3/4 in. birch. Never had a problem.

This is the first time I've heard that.

We mostly used 3/8 in. 10 TPI blades made up locally; don't remember what tooth shape. Blades typically lasted 3 months or more.

Very curious to see what others have to say.


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## TopamaxSurvivor (May 2, 2008)

Was it Chinese junk plywood from a big box? May have hit metal in it?


> ?


??? ;-((


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## Dark_Lightning (Nov 20, 2009)

I use the Craftsman blades from their store and cut plywood (even Baltic birch) all the time, and don't see that much problem.


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## JuniorJoiner (Dec 24, 2008)

I was using a 3 tpi viking bandsaw blade from LV. i'm not saying it catastrophically failed, but it was significantly dulled so much so that i changed it. 
I could see if it was cheap ply, but this stuff is pretty good compared to everything else I have used. 
It didn't seem that I hit any foreign objects, and I went and checked after That question was asked, there were some knots in the internal plys of the substrate, but no noticeable metal.

still wondering why it happened.


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## TopamaxSurvivor (May 2, 2008)

Might be interesting to see if yiou get any sparks running a few pieces of scrap across a grinding wheel if you have one. There has been quit a bit of talk online about what is being put in plywod as filler material, not just chunks of metal.


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## Nomad62 (Apr 20, 2010)

It may be the manufacturer used a gritty wood for the filler layers, like a locust, and only put the birch on the outer layer? Just a guess, of course. I've only heard to not run it thru a jointer, planer, shaper, etc. because of the cutter speed blowing it up. Guess I don't cut a lot of plywood but haven't noticed any problems when I do.


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## Loren (May 30, 2008)

Plywood is glued up with plastic resin glues - the stuff is brittle and
hard. It wrecks Japanese handsaw blades too.

One of the advantages of a larger band saw is you can run wider,
carbide tipped blades on them. With carbide, you can saw plywood
just fine.


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## Nomad62 (Apr 20, 2010)

Got to thinking about this last weekend, maybe the glue in the plywood has stuck to the teeth of your blade, making it seem dull when it really only needs a good cleaning…?


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## stamper (May 23, 2010)

My shop is 20+ years old and I have never had any trouble cutting plywood on my bandsaw. Just recently cut a batch of Corian for pen blanks, no problems there either.


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## JuniorJoiner (Dec 24, 2008)

I have looked at this blade quite a few times since posting this, there is quite a glaze built on the teeth, nothing that couldn't be cleaned. but enough to reduce cutting.
The blade is somewhat usable since cleaned, but it is still dull compared to before the plywood. 
I certainly won't be cutting any more of it.


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