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View Full Version : How to tell if a bandsaw blade is ready to break



Brendan Plavis
04-29-2010, 8:10 PM
I noticed that there is about a .75inch piece on the band that is unlike the rest of the blade. It is very rough, and scratched. Is this normal, or should I be worrying? I would hate for one of them puppies to come flying at me... :eek:

Thanks

Neil Brooks
04-29-2010, 8:11 PM
Could be the weld.

Can you post a pic ?

Nick Mastropietro
04-29-2010, 8:12 PM
Just guessing without seeing the blade, but it's likely the place where the two ends of the blade stock were welded together and then the weld ground smooth.

Brendan Plavis
04-29-2010, 8:15 PM
That sounds right I guess, I wasnt thinking about that.. I forgot that they grind the welds afterwards...

Prashun Patel
04-29-2010, 9:18 PM
Even if it snaps - which one has on me - they sound is usually worse than the bite.

Van Huskey
04-29-2010, 10:34 PM
Even if it snaps - which one has on me - they sound is usually worse than the bite.

+1

It probably is the weld.

Did you hone the back of the blade, not related to this per se but thinking about the weld reminded me you may not have known to.

Jeff Willard
04-29-2010, 10:37 PM
They do sometimes break, and they won't fly.

Dave Verstraete
04-30-2010, 7:44 AM
Brendon
Don't worry about it flying at you. As an older toolmaker, I spent countless hours on a band saw during my apprenticeship. I have broken a blade more than a hundred times (probably less than a thousand). It never came close to flying anywhere. A bandsaw is at its most dangerous moment (IMHO) when it exits the workpiece and you aren't watching where your fingers are.

Prashun Patel
04-30-2010, 7:52 AM
"A bandsaw is at its most dangerous moment (IMHO) when it exits the workpiece and you aren't watching where your fingers are."

Amen to that.

Here's to outfeed support and stopping cuts short when possible and finishing from the other side...

Chuck Saunders
04-30-2010, 8:22 AM
Blades don't fly when broken, but, it is wise not to open the doors until the upper wheel has stopped turning.

Robert Parrish
04-30-2010, 9:01 AM
I've had two break i the last 3 months and neither came off all the way. But they scared the hell out of me. BTW these were Timber Wolf, one broke at the weld and the other at a different place.

Will Rowland
04-30-2010, 10:34 AM
Actually, last night I was folding a bandsaw blade for storage, and it broke (at the weld), whipping around and slicing a nice gash in my finger.

From here on out I'll be wearing gloves and a faceshield whenever I am folding up the blades.

Mike Cruz
04-30-2010, 11:16 AM
Actually, I know someone that got a really nasty cut on his thumb when the blade snapped. But even he will tell you it was a freak accident.

I don't know the details of what actually happened, but I can only imagine he had the guides way up (large capacity cut) and the blade snapped in that space, flinging one end to the side, catching his thumb. Don't know for certain.

But will attest to the sound being shocking, and usually it won't catch you...

Oh, and YES, watch your fingers upon exiting the cut!

mark kosse
04-30-2010, 12:52 PM
I know when one of my students, Jan Carlos, walks up to the bandsaw that the blade is about to break. :)

George Petersen
04-30-2010, 2:47 PM
When I hear a TICK-TICK-TICK-TICK, I shut off the saw and back away. Inspect the blade for a horizontal hairline crack, usually- but not always-at the weld. The ticking sound often warns of imminent breakage, sometimes the blade will break about the same time as I recognize the ticking sound.
About half the time a blade breaks I get no warning (that I noticed)
The expensive Timberwolf blades break as often as the cheaper ones from Grizzly. I do very little resawing, mostly scrolling 3 inch thick dry walnut, and use 3/8 - 4TPI blades. Breakage is fairly uncommon, usually they get dulled a bit and I change them out.
I have never been hurt by a breaking blade, the design of modern saws can be thanked for that, and most of the damage is to the interior of the saw itself.
Broken blades usually get bent up bad enough they cannot be re-welded and expected to run true. Throw them away and get on with it.

Brendan Plavis
04-30-2010, 2:55 PM
Alright, thanks. New to the bandsaw, and was worried that I might want to invest in kevlar for being near the thing....

But I do hear ya Dave.... my folks were wondering why I seem to make a new push stick every couple days.... My rule is... push stick can get chewed into by the blade... but fingers... I would rather not...