Bandsaw blades breaking.

[9shooter]

I just started sawing with a LT40 super and am having a problem breaking bands.  The tension seemed to be set right. (according to the tension gage) The last band that broke was after just the 3rd pass through a spalted beech log.(12") The blade was out of the wood. One of the bands did show stress cracks in several places, so it might have been too old. I was sawing a bit too slow. the lube had run out, but we sawed all winter without it. Any ideas?

[logwalker]

Are these new blades that are breaking? Who's blades are they?

[Chuck White]

If I find a crack in one of my blades, it goes directly into the recycle bin.  They're nothing to mess with. 

[Chuck White]

In addition to my above post:
When a blade breaks, it can take out your band belts and you are out of business.
It can also break into several pieces and go "who knows where".  Not a good thing.
Usually the end will head towards the sawdust chute.

[backwoods sawyer]

How many hours of run time are you getting out of your saws?

[Magicman]

One of the bands did show stress cracks in several places, so it might have been too old.

If a band showed stress cracks, it was already broken and should not have been put on the mill.

There two kinds of bands.  Those that are broken, and those that are going to break.  Bottom line, all bands break  They wear out.  They will travel around the bandwheels only so many times.

It simply sounds like yours are reaching the end of their lifecycle.....

[9shooter]

They are wood-mizer bands. I didn't see any stress cracks in the bands before putting them on the saw. There is some question about the band wheel belts. One shows some wear and a new set is on the way. I will pay more attention to the cut. I am new at sawing so I need to get a little experience with knowing when the bands start to dull.

[backwoods sawyer]

A good rule of thumb to follow is 2-4 saws per day depending on how long your days are.

[ladylake]

If your belts are worn so much that the band is touching metal your blades will break fast.   Steve

[sdunston]

In looking at the cut were the band breaks is it diving, rising, is there a knot. What I am asking is what was the last thing the cut looked like before the blade
failed.
Sam

[terrifictimbersllc]

Never let anyone be on the drive side of the sawmill when you are cutting.  Usually broken blades don't cause much excitement.  But once in my first year of sawing I had a Wood-Mizer blade shred and shoot out the drive side like shrapnel.   I picked up pieces over 30 feet from the mill in a fairly wide angle.   A new blade during the end of an edging cut.   Never saw it happen again but I always shut down if anyone goes into a zone within about 30 feet of a 45 degree cone coming out of the exit chute.  Eye protection on everyone who is watching within 50 feet no matter where they are.

[Magicman]

Sometimes, they will come out of the chute.  Bibby has some real "jewels".
 

[sgschwend]

It is hard for new sawyers to know when a saw is not sharp.  And it is not that difficult for one with experience to know when a saw is ready to be changed.

Fight the erg to keep going.  If you have a hydraulic mill changing every two hours is not unreasonable.  Avoid cutting through the heavy bark and dirt.  As you get uses to setting the feed speed you will start to see when the saw will not cut as fast.  Going too slow dulls the saw. 

Some mills have an option to cut an entry kerf so the saw does not need to cut through the bark.  I don't have one of those so I rotate my logs into the saw direction.  I only need to cut through the bark on the first cut, the subsequent cuts will be through clean wood.  That really helped my saw stay sharp!

[Chuck White]

If you have your own sharpener and setter, you will seem to pull your blades a little quicker. Thus, they last longer. 
You (at least I did) seem to push them a little harder if you have to take them somewhere besides home to be sharpened & set!

[ladylake]

That's another advantage of having your own sharpener and setter, they come off at the first sign of getting dull.  Steve

[pineywoods]

As others have stated, band blades have a limited lifespan. I broke 3 blades yesterday within an hour sawing dry cedar logs. All 3 were from the same box of blades, had been sharpened the same number of times, and probably had sawn roughly the same amount of boards. With experience, you will learn to tell when a blade is so dull it needs changing.
Otherwise here's a couple of ways to easily tell.  1. Put a bicycle speedometer on one of the bandwheels (cheep about $10). This will show the speed of the blade through the log, the speed will drop off when the blade gets dull. 2. Watch the blade when it exits out the end of the log. If the blade drops below the kerf, it's already dull, but will continue to cut if you insist. Just don't expect first class lumber.

[Slingshot]

  pineywoods;
                       You stated you were cutting dry cedar logs. Are they rather difficult to saw?
    I have a neighbor who has some dry cedar trees he has offered me at what might be a
    good price but they have been down about a year and a half. They are trimmed and dragged
    into a pile but not cut into manageable logs. Wondering if I should pass on them? I don't need
    any cedar now but looking to need some in the near future.



_______________________
Charles

[pineywoods]

  pineywoods;
                       You stated you were cutting dry cedar logs. Are they rather difficult to saw?
    I have a neighbor who has some dry cedar trees he has offered me at what might be a
    good price but they have been down about a year and a half. They are trimmed and dragged
    into a pile but not cut into manageable logs. Wondering if I should pass on them? I don't need
    any cedar now but looking to need some in the near future.



_______________________
Charles

Dry cedar saws quite easily. The only problem is ME. The fine dust gives my sinus fits. I have 2 fans plus a sawdust blower on my mill, one blowing on my back and another blowing downward on my head. I still can't saw the stuff when the wind is blowing the wrong way. Cedar makes very nice lumber.

[Papa1stuff]

  pineywoods;
                       You stated you were cutting dry cedar logs. Are they rather difficult to saw?
    I have a neighbor who has some dry cedar trees he has offered me at what might be a
    good price but they have been down about a year and a half. They are trimmed and dragged
    into a pile but not cut into manageable logs. Wondering if I should pass on them? I don't need
    any cedar now but looking to need some in the near future.



_______________________
Charles

Dry cedar saws quite easily. The only problem is ME. The fine dust gives my sinus fits. I have 2 fans plus a sawdust blower on my mill, one blowing on my back and another blowing downward on my head. I still can't saw the stuff when the wind is blowing the wrong way. Cedar makes very nice lumber.

Pineywoods I see you say you have a sawdust blower on your mill, could you tell me what the HP is . I also have  LT40 SH and am thinking of putting a blower on ! Thanks

[pineywoods]

re-sawdust blower on lt40  click here
http://www.forestryforum.com/board/index.php/topic,29689.msg427605.html#msg427605

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