Bandsaw blade care

[Bob Jones 5443]

Is turning the top wheel a bit more than a half-turn every day or so as good as releasing the tension when the saw is not in use? Turning prevents the blade from deforming onto the curve of the wheel, but is there another benefit to pulling the tension release lever?

[Steve Eure]

Maybe it's my imagination, but when I have left the tension on my bandsaw for several days, It seems like the blade has less tension in it then when I was using it. As I said, it could be just my imagination.
I was told by an older woodworker that it could also put a "set" in the blade where it goes around the wheel. Don't know if that is true, but why take the chance since I have a tension lever on my saw.

[Rod Sheridan]

In 40 years of using band saws in both industry and at home, I’ve only removed blade tension to change blades....Rod

[John K Jordan]

Is turning the top wheel a bit more than a half-turn every day or so as good as releasing the tension when the saw is not in use? Turning prevents the blade from deforming onto the curve of the wheel, but is there another benefit to pulling the tension release lever?

The tensioning question almost always has replies from two camps - one always releases the tension and one never releases the tension. The manuals in the bandsaws I have say to release the tension. The manufacturers don't say if they are just saying that to protect themselves, because it might be a good idea, or if it is based on specific research and experience.

For example, for my 18" Rikon: 10. Release blade tension when the saw will not be used for a long period of time.
My older 14" Delta: "Release the tension when the machine is not in use."
The instructions for my Woodmizer sawmill are clear: "CAUTION Release the blade tension when the mill is not in use."

I wonder if the size and type of blade, wheels, and saw make a difference, say spring steel vs bimetal or carbide blades, hard steel wheels vs softer tires, cheap shop saw vs heavy industrial model.

What I do: On my shop woodcutting bandsaws I leave the saw tensioned if I plan on using it in the next day or so. If I'm not planning to use it for a while I release the tension. For the sawmill I always release the tension when done sawing for the day - the steel in those blades is wide and thick and the they run directly on steel wheels AND the amount of tension needed is very high - tensioning requires using both hands to turn a heavy steel handle.

I guess the bottom line is each person has to decide what to do!

BTW, one of the problems with releasing tension is forgetting to retension when starting the saw! I saw this idea on one of the forums (maybe here?) for a tension reminder so I made one:

tension.jpg

JKJ

[Lee Schierer]

Is turning the top wheel a bit more than a half-turn every day or so as good as releasing the tension when the saw is not in use? Turning prevents the blade from deforming onto the curve of the wheel, but is there another benefit to pulling the tension release lever?

That only works if you are in your shop everyday and also remember to turn the wheel. Personally, I just release the tension and then set the tension again the next time I use the saw.

Since band saw blades are routinely stored coiled in three or more loops I doubt that having a blade remain in one position on the wheel that is larger in diameter than those coils is going to cause any permanent set.

[Patrick Kane]

I have a resaw king that is from 2004. I cant say what the previous owner did with it, but for the 4ish years ive owned it, its been under tension for weeks and months when its on the saw. When its not on the saw, its coiled and on the hook. If you have a smaller saw, like 14-16" then maybe you want to release tension? I think the smaller diameter wheels are harsher on blades, generally speaking. Mine is 20", and probably on the edge of tension/de-tension. If I had a 36" saw, i wouldnt even think about it. I know a lot of people worry about this question, but I havent seen any reason to do one or the other. Furthermore, eventually all the really smart bandsaw folks get pulled into this discussion, and they havent swayed me one way or the other. Im lazy, i leave my saw tensioned.

[Jim Becker]

In 40 years of using band saws in both industry and at home, I’ve only removed blade tension to change blades....Rod

I tend to not release tension, either...

[Doug Dawson]

I tend to not release tension, either...

Another point in favor of the Laguna 18BX: it's difficult to _deliberately_ use the saw with the tension lever in its released position.

[Andrew Seemann]

I do not believe I have ever seen or heard of a bandsaw being relieved of tension for reasons other than changing a blade in actual any shop I have ever been in in my life.

I always wondered about bandsaws that get used on a daily basis, like the Tannewitz and DoAll we had in the machine shop I worked in. Those blades and saws got more stress on them than any bandsaw at rest, yet they worked just fine and they were decades old then (and are 30 years older now). Same with a 14 Delta or a 12 Crafsman. How does using a bandsaw not deform it when leaving it at rest supposedly does? And blades, every blade I have taken off a bandsaw that wasn't damaged was round, not ovaded from being left at rest. And wouldn't they need to be left in the exact same position to take a permanent set? Otherwise the next night would counteract the previous nights set (as would turning it on the next morning).

We don't take the tension off the rubber V belts on machines at the end of the day, and those are far more susceptible to deformation than tempered spring steel.

[Doug Dawson]

I always wondered about bandsaws that get used on a daily basis, like the Tannewitz and DoAll we had in the machine shop I worked in. Those blades and saws got more stress on them than any bandsaw at rest, yet they worked just fine and they were decades old then (and are 30 years older now). Same with a 14 Delta or a 12 Crafsman. How does using a bandsaw not deform it when leaving it at rest supposedly does? And blades, every blade I have taken off a bandsaw that wasn't damaged was round, not ovaded from being left at rest. And wouldn't they need to be left in the exact same position to take a permanent set? Otherwise the next night would counteract the previous nights set (as would turning it on the next morning).

I used to blame the so-so performance of my 14" Delta on forgetting to de-tension the blade. On a related note, how do you get your dog to stop farting,..

Blades in everyday use that aren't de-tensioned are still round because they stop in different places every day, etc. I'd be more concerned with whether the frame distorted from "plastic deformation". The industrial saws probably wouldn't have this issue.

[mike stenson]

I used to blame the so-so performance of my 14" Delta on forgetting to de-tension the blade. On a related note, how do you get your dog to stop farting,..

Blades in everyday use that aren't de-tensioned are still round because they stop in different places every day, etc. I'd be more concerned with whether the frame distorted from "plastic deformation". The industrial saws probably wouldn't have this issue.

I imagine the tension spring would simply lose tension before you distort a cast iron frame.

[Doug Dawson]

I imagine the tension spring would simply lose tension before you distort a cast iron frame.

It's the tension delivered to the frame that matters, no matter if the spring is worn or not. The frame+spring functions as a system, they both see the same tension. Agreed, in the short term the spring may suffer first.

[Paul F Franklin]

BTW, one of the problems with releasing tension is forgetting to retension when starting the saw!

When I tension the blade, I turn the bandsaw task light on. When I turn the light off, I de-tension the blade. Works for me.

[Mark Daily]

I have a 14” Grizzly BS that I use infrequently. I release the tension when not in use to prevent deforming the rubber on the wheels.
The saw has a tension lever so it is easy to do and there’s no “penalty” in releasing the tension.

Any thoughts on if I’m really saving the wheel rubber?

[Erik Loza]

There are blades, and then THERE ARE BLADES. It probably doesn’t matter on a small saw with the thin blade but on a big saw with a 1” carbide, I’m pretty convinced you could fatigue the blade if you left it under tension all the time. Just my experience.

Erik