Metal-cutting bandsaw blade getting stuck in kerf

[joshuabardwell]

Here's something I can't figure out. The blade of my metal-cutting horizontal bandsaw is getting stuck in the kerf. This seems like it should be pretty much impossible, since the teeth should be wider than the body of the blade, so the kerf should always be wide enough to clear the body of the blade. At first, I thought maybe the work piece shifted to bind the blade in the kerf, but that's not it. What happens is the blade stops moving and when I cut power and try to raise it out of the kerf, it is well and truly jammed in there. I have to wiggle the work piece back and forth to free it.

I have worn out more than one blade, but I have never had this happen before. Is this a common failure mode? Maybe the teeth have broken off somewhere? Still, it seems like as long as there were a few teeth still cutting, a kerf would open up. I can't really imagine what's gone wrong here. I don't see how the body of the blade could be wider than the teeth. The blade isn't new, but I don't think it should be at the end of its life either.

 

[mjncad]

What brand of blade are you using? I use Starrett or Lenox.

It almost sounds like friction is heating up the blade causing it to expand and bind. Do you have the blade tension set correctly? Do you have the right amount of downforce dialed in? Too little and the blade rides on the metal and doesn't cut well. It just gets hot and wears down the teeth. Too much downforce and the teeth dig in more than the motor can supply power to actually provide a clean cut. Is your bandsaw a dry or wet cut saw? Are your blade guides aligned properly?

Bandsaws are great tools; but they are like finicky sports cars that need to be tuned up regularly.

 

[chim]

What are you cutting? If it's a plain old piece of pipe, andlg or channel it shouldn't be a problem with a good blade. On the other hand, if you're cutting soomething that had any fab/welding work done on it the piece could be tightening up on the blade because it's trying to pull in the direction it wants to shrink.

 

[Gem99ultra]

I've had my cheap bandsaw do that too. It happens on mine when I have the guides set too far apart, too loose, or the blade misaligned. That, of course also presents a malaligned cut, and often a broken blade.

Naturally, I've learned that a little more care in setup saves a lot of time (and money) in blade replacement.

 

[caps]

As the blades wear they also lose some of their set and the teeth get duller on their outer edges causing them to bind up more easily, especially when some of the conditions previously cited occur.

 

[joshuabardwell]

What are you cutting?

Just a piece of flat bar stock.

 

[Wyobuckaroo]

With what little info to work with here are some facts.

It is generally figured you want 2-2 1/2 teeth engaged in the cut at any one time. Thicker material = fewer teeth per inch of blade. There must be room for the gullet of the tooth to carry away the chips.

So I'm going to guess too many teeth per inch, and well worn blade.....

Good luck.....

 

[kevin37b]

Did you ever fix the chop saw blade problem ?

 

[joshuabardwell]

Did you ever fix the chop saw blade problem ?

I haven't done a ton of fabrication since that project, so I can't say for sure, but I think it may have to do with that batch of steel or something. I have cut up some bar stock into coupons for practice welding with no problem, on the same blade that was acting dead on the tubing. It may have been glazing on the blade, since cutting a piece of bar stock is the prescription for that.

The real test would be to go back and cut a piece of that tubing again and see if the blade dies again, I guess.

 

[joshuabardwell]

Thanks everybody for the feedback. Looks like a new blade is in order. I just hadn't had one fail exactly like this before. I'm surprised that the blade can bind up in the kerf this way, but there you go.

I have heard that whenever something goes wrong with your bandsaw, the first step is always a new blade. Words to live by...