# What Causes Band Saw Blades To Break



## Jerry Bowen (Jun 25, 2011)

I'm breaking blades on my band saw, not very often just often enough to make me wonder if this is just normal or am I setting the blades to tight. I'm talking about half inch Timber wolf blades right now. The blades are set up as per the Snodgrass recommendation as as far as the guides and and position on the tires are concerned and the saw cuts perfect when working, I'm referring to re-sawing when I say perfect, abd all other cuts are fine, but it seems as though the instructions that I read about tention are a little vague. So is why I am asking the question about it.

Jerry


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## denniswoody (Dec 11, 2011)

It is abnormal for a band saw blade to break. If the blade is cutting OK the logical conclusion, to me anyway, is to start looking at too much tension or a feed rate that is excessively fast.


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## Jerry Bowen (Jun 25, 2011)

denniswoody said:


> It is abnormal for a band saw blade to break. If the blade is cutting OK the logical conclusion, to me anyway, is to start looking at too much tension or a feed rate that is excessively fast.


Thanks Dennis,
What is a normal feed rate, I think that I am cutting slow, but the term feed rate is like tension setting, not an exact issue. However, from what you are saying Dennis, I do suspect that I'm setting the tention to tight. I think that after I set up a new blade and it is cutting right I will slowly let the tension off until the cut no longer is correct and then tighten back up just enough to get the cut right again. What do you thing?

Jerry


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## Dmeadows (Jun 28, 2011)

Jerry, are they breaking at the weld? If so, I have heard of some issue with TW blades doing that. If not could be at least partially a tension issue. Else technique? Are you using the primarily for resaw? What exactly are you doing when they break?

I know... more questions than answers!


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## JOAT (Apr 9, 2010)

Jerry Bowen said:


> I'm breaking blades on my band saw, not very often just often enough to make me wonder


Just exactly HOW often?


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## Cherryville Chuck (Sep 28, 2010)

I've always heard that you are better off with too much tension than not enough in respect to breakage.

One more question; are the blades new or have they been resharpened? If they have been resharpened and the saw filer left sharp corners in the gullets that will break blades.


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## paduke (Mar 28, 2010)

TW blades are a low tension blade. I was setting tension to tight initially also and breaking blades. ie on my Grizzly BS setting for 1/4" TW blade is less than 1/8" on tension scale. Salesman at woodcraft suggested I was using too much tension He was right.


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## Jerry Bowen (Jun 25, 2011)

Severa questions to answer. I'm inclinded to think that I am overtentioning the blade. These are all new plades, have never had a blade resharpened, only use new blades. I have broken two of these half in blades in the past six months, but my saw is not used a lot. I was cutting the top off of of a box when the last one broke. I noticed the brade beginning to not run true when I startd th4 cut which probably meant that the blade was already coming apar. I don't know if the break was at the weld or not, will have to have a ook but I don't think that it was. Also, it is possibile that I had been feeding the cut to fast on some previoious cuts. Lot of "I'm sure issues here" but the answer that breaking on a regular basis the the most important comment indicating operator error for the most part.

Jerry


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## Cherryville Chuck (Sep 28, 2010)

You can try getting them rewelded. They might last quite a while yet.


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## Wood Chip (Apr 10, 2011)

I can't imagine this could actually cause breaks, but having all the guides properly adjusted goes a long way toward stability improves blade longevity. But I suspect you knew this.


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## Jerry Bowen (Jun 25, 2011)

Cherryville Chuck said:


> You can try getting them rewelded. They might last quite a while yet.



I have assumed that by the time you freight both ways, get it welded, and might well get it sharpened too, that it is just about as easy does not cost much more to just buy a new blade, I'll order a couple of new ones from Grizzly this morning.

Thanks for the suggestion though, 

Jerry


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## Slappy (Nov 2, 2013)

are you releasing the tension when your done resawing ?


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## david_de (Jun 3, 2013)

Matthias Wandel has a blade tension gauge on his site and has done some testing in this area. I built one of his wooden band saws and they do not come with a gauge. I have a gauge on a Delta band saw but I am not sure how accurate it is. I started building the gauge thinking it would be handy but have not finished it yet to see how well it works.


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## Jerry Bowen (Jun 25, 2011)

Slappy said:


> are you releasing the tension when your done resawing ?


No I'm not, I had read that this was not necessary, but that just might be the problem let's hear so more about this point. Makes sense that Grizzly didn't put that feature on the saw for decoration did they. Thanks for meminding me about that, I wonder if other members have any comments on the matter..

Jerry


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## Cherryville Chuck (Sep 28, 2010)

Jerry Bowen said:


> No I'm not, I had read that this was not necessary, but that just might be the problem let's hear so more about this point. Makes sense that Grizzly didn't put that feature on the saw for decoration did they. Thanks for meminding me about that, I wonder if other members have any comments on the matter..
> 
> Jerry


I always release mine. They say it is hard on the tires. I don't know about the blade.


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## Marco (Feb 21, 2009)

Cherryville Chuck said:


> I always release mine. They say it is hard on the tires. I don't know about the blade.


I thought I read where not releasing the tension would aid in stretching the blade?

Hate to say I busted a blade.............. too much tension in thick wood and a heck of a curve! Thankfully the blade stuck in the wood and the other end stayed away from flesh.


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## mlerchenmuller (Sep 26, 2011)

Sounds like too much tension. Do you release the tension when not in use? This will prolong blade life.


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## MAFoElffen (Jun 8, 2012)

david_de said:


> Matthias Wandel has a blade tension gauge on his site and has done some testing in this area. I built one of his wooden band saws and they do not come with a gauge. I have a gauge on a Delta band saw but I am not sure how accurate it is. I started building the gauge thinking it would be handy but have not finished it yet to see how well it works.


David-
I remember that GulfCoastGuy made one of those and liked it. Haven't heard much from him lately. Curious how it does for you and what you think about it.

I've broke a resaw blade (and a few more)... un-nerving. I was resawing... as the blade was in the kurf and cutting through a knot, the non-squared stock came loose from my jig and tilted... 

It didn't break on that first try... Actually that time the blade bent as the blade came off the tires. It broke after I straightened the blade, put it back on the tires and got it stuck again, in the same piece of wood, in the same spot, doing the same thing.

You know... I just realized, I have not done much resawing at all since then...


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## AxlMyk (Jun 13, 2006)

Timberwolf recommends using the flutter method to tension blades. That's how I do all of mine, and have never had a blade break, and always get a great re-saw, even with 12" inch stock on my 14" saw. I never de-tension it.


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## mrmistake (Nov 5, 2013)

*Breaking blades*

Jerry
I use timber Wolf blades and there are instructions in there catalog on how to adjust blade tension (VERY IMPORTANT). the tension I use is the the least I can.I raise the guide bar up all the way, move all the bearings and guides away from the blade and run saw while lessening the tension knob until blade starts to wobble then tighten until blade until it stops vibrating. Read there instructions before you follow my advice.I also always release blade tension EVERY time I'm done cutting to lesson stress on blade. ALWAYS use a full face shield while your doing this procedure! I always leave a small sign on the table when the blade is loose so I don"t forget the blade is loose before I turn it on. there are other things I do but trying to keep this short as possible. hope this helps
Ed


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## mrmistake (Nov 5, 2013)

Jerry
. Read Timber Wolf's instructions on how to adjust blade tension.( always wear full face shield while doing this procedure)! One thing I ALWAYS do is release blade tension Every time I'm done cutting. Very important to keep lessen blade stress on TW blades.I also keep a small sign on saw table reminding me blade is loose before turning on saw.I do other things but to keep this short I'll omit for now.hope this helps.
Ed


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## Jerry Bowen (Jun 25, 2011)

mrmistake said:


> Jerry
> . Read Timber Wolf's instructions on how to adjust blade tension.( always wear full face shield while doing this procedure)! One thing I ALWAYS do is release blade tension Every time I'm done cutting. Very important to keep lessen blade stress on TW blades.I also keep a small sign on saw table reminding me blade is loose before turning on saw.I do other things but to keep this short I'll omit for now.hope this helps.
> Ed



Thanks Ed,
I had already gone on line and read the instructions that you are referring to. 

I have broken three blades in the time that I have had my Grizzly 17" saw and each time the broken blade has been retained inside of the closed doors. Because of the blade never offering to bd dangerous when it broke, I have not given any thought about it being when it breaks until now. Thanks for the heads up, I sure will keep it in mind and be more careful, I must have a guardian angel in that I have not gotten hurt yet and have done so many dangerous things since I started learning about woodworking. I do try to be careful, but sometimes not knowing of potential danger can get a person in trouble no matter how careful his is trying to be.

Jerry






Jerry


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## bosox (Jun 12, 2012)

Most basic reasons why band saw blade breaks are over tension, blade tracking, worn tires, bad welds,
wrong blade, bad guides, over feeding and wrong speed, other reasons could be .


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## greenacres2 (Dec 23, 2011)

Besides relaxing the tension on the BS, i try to run all the belted tools at least once a week--at a minimum i hand turn them a little. With the winter and not a lot of unheated shop time, it just seems like the belts would kind of form to a stationary spot, especially in the cold. May not do be any real benefit, but i feel better!!

earl


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## jeff.fredrick (May 20, 2010)

Jerry

I've found that releasing the tension at the end of the day and only reapplying it when you use the bandsaw again is another way of minimising breaks. My bandsaw blade supplier rewelds for free if it breaks on the weld.

Regards Jeff


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## rpludwig (Nov 22, 2011)

I too have a Grizzly bandsaw and use TW blades, mostly 1/4". I've broken two in 3 years of moderate use which I attributed to too much tension, too fast feed rate, and pushing a dull blade to the limit on hardwood.

Since the last break and after some research, I relax the tension after each use, lower the guides onto the table as a reminder that it is untensioned, and change blades more often as they show wear. Also have used some blade & tool cleaner which removes the gum and extends blade life. Pay close attention to your guide adjustments and tweak as necessary. Haven't broken one since....fwiw.


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## Jerry Bowen (Jun 25, 2011)

rpludwig said:


> I too have a Grizzly bandsaw and use TW blades, mostly 1/4". I've broken two in 3 years of moderate use which I attributed to too much tension, too fast feed rate, and pushing a dull blade to the limit on hardwood.
> 
> Since the last break and after some research, I relax the tension after each use, lower the guides onto the table as a reminder that it is untensioned, and change blades more often as they show wear. Also have used some blade & tool cleaner which removes the gum and extends blade life. Pay close attention to your guide adjustments and tweak as necessary. Haven't broken one since....fwiw.


Ron, you might look at my latest thread on what happened to me after installing the blade. The thread is named, "This Happened To Me".

Jerry


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