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Bob Jones 5443
01-17-2020, 1:26 AM
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
01-17-2020, 6:12 AM
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
01-17-2020, 6:37 AM
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
01-17-2020, 8:12 AM
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:

423861

JKJ

Lee Schierer
01-17-2020, 9:08 AM
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
01-17-2020, 9:22 AM
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
01-17-2020, 10:00 AM
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
01-17-2020, 10:04 AM
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
01-17-2020, 10:24 AM
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
01-17-2020, 10:39 AM
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
01-17-2020, 10:44 AM
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
01-17-2020, 11:02 AM
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
01-17-2020, 12:48 PM
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
01-17-2020, 12:59 PM
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
01-17-2020, 1:28 PM
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

Kris Cook
01-17-2020, 1:29 PM
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.

This is what I do as well.

I always assumed the de-tensioning was as much about saving unnecessary bearing load as anything.

Rod Sheridan
01-17-2020, 2:14 PM
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?

Mark, since I've never done it in 40 years, I doubt if you are saving the tire.............Rod.

John TenEyck
01-17-2020, 3:22 PM
The blade, frame, and spring all will happily sit there for years under tension without complaint, as long as you stay within the max. spring tension of the saw. Rubber tires, however, can and will take a set or stretch, like they did on my 14" Delta. It was so bad that the saw would shake pretty badly for several minutes each time I turned it on if it had sat unused overnight or longer. This is exactly the reason Woodlander cites on their bandsaw lumber mills of why tension should be released when it's not being used, as John J. referenced above. Anyway, I finally put new tires on it and leave it under tension w/o issues now. My larger 17" Grizzly has a quick release lever, and I use it infrequently, so I release the tension when not using it.

Patrick Kane, how much wood have you cut on that Resaw King blade? I've never had that kind of life out of any blade, including carbide, before it needed to be re-sharpened.

John

Rod Sheridan
01-17-2020, 3:42 PM
John, my band saw has been in the shop for 18 years without tire issue, maybe it's due to the tire material?

Regards, Rod.

John TenEyck
01-17-2020, 6:34 PM
John, my band saw has been in the shop for 18 years without tire issue, maybe it's due to the tire material?

Regards, Rod.

I'm quite sure you are correct, Rod. Since I changed the tires on my 14" Delta I haven't had a problem and leave it under tension. I'm pretty sure tires that are vulcanized to the wheel, like on my Grizzly, don't suffer from this problem.

John

Zachary Hoyt
01-18-2020, 8:37 AM
I never de-tension the sawmill except to change blades, the blade runs on 4.80-12 trailer tires and they don't seem to care. I also never take the tension off the shop bandsaws except to change blades. My little Rikon 10-305 had the same blade in it for over a year, under tension, and I didn't see any negative effects to the tires or the blade. My 18" Jet has urethane tires from Sulphur Grove Tool and they are very hard and non-stretchy, so I can't imagine that they could be affected by the blade tension.
Zach

Alan Lightstone
01-18-2020, 8:43 AM
I put a couple of labels on my bandsaw next to the on/off switch.

It says Blade Tension On
or Blade Tension Off.

I put a magnet next to whichever tension level I keep it at.

That being said, I forget to release the tension a bunch. But at least I don't try to start my beast with the tension down.

John K Jordan
01-18-2020, 9:11 AM
I put a couple of labels on my bandsaw next to the on/off switch.
It says Blade Tension On
or Blade Tension Off.
I put a magnet next to whichever tension level I keep it at.
That being said, I forget to release the tension a bunch. But at least I don't try to start my beast with the tension down.

Ha, I once forgot to retension and didn't notice until getting into the first part of teaching a bandsaw class! The saw was still cutting but I was puzzled with some drift and other problems until I remembered the tension. How embarrassing!

Did you happen to see the picture I posted about the tension reminder: For me it is foolproof since I put it on the table every time I release tension. I saw this idea on one forum or another, maybe here. I wish I had wrotten it down on the piece of wood so I could credit the person. Here's the picture again. I hang it on the quick release lever.

423958

JKJ

Mark Daily
01-18-2020, 1:03 PM
Mark, since I've never done it in 40 years, I doubt if you are saving the tire.............Rod.

Thanks Rod- that’s something to consider.

Doug Garson
01-18-2020, 1:35 PM
Ha, I once forgot to retension and didn't notice until getting into the first part of teaching a bandsaw class! The saw was still cutting but I was puzzled with some drift and other problems until I remembered the tension. How embarrassing!

Did you happen to see the picture I posted about the tension reminder: For me it is foolproof since I put it on the table every time I release tension. I saw this idea on one forum or another, maybe here. I wish I had wrotten it down on the piece of wood so I could credit the person. Here's the picture again. I hang it on the quick release lever.

423958

JKJ
Another version of this method is to use a carabiner. Clip it on the tension mechanism when tensioned and move it to around the blade when detensioned.