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Bandsaw Blade Tension


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How tight do you go on your horizontal bandsaw. I just upgraded to a 10"x16" capacity saw with a 1"x132" blade. I've heard to tension until it rings when plucked, but that feels like I'm putting too much strain on the machine to get to that point. How do you know when the blade is tight enough?

Thanks,

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I'm having the same problem with finding correct tension.  I have a HF saw and the blade keeps jumping off the drive wheels.  I have had the tension as tight as I could hand tighten the tension knob and that causes it to jump after only a few seconds of cutting.  I am now backing it off to "firm" tension on the knob.  We will see.

All the instructions say is that it should be tight enough that the power and idler wheels don't slip.  Big help.

"By hammer and hand all arts do stand."

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Don't those bandsaws have tracking adjustment rollers/wheels?  Not the same, but my small belt grinder has an adjustment wheel with an oval cross-section that you adjust in and out to change the tracking.

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Over tensioning band saw blades causes wear in the wheels and when bearing wear causes them to start running out of track you can't keep blades on them.

Listening to the "tng" to judge tension is an acquired skill. If you haven't heard a properly tensioned blade's "tng" how are you going to tell? 

Check to make sure there's no lash in the pully wheel bearings by pushing on top and pulling on bottom to see if they move. 

You should be able to move the blade a LITTLE bit by hand most saws will say how much on a plaque, sometimes inside the upper wheel cover.

Turn your saw on once without a blade to get a idea of what it sounds like without a load. When you put a new blade on snug it up and turn it on. If it stays on the pullies you have it close now tension while it's running and listen closely. When you hear the motor and gears start to work, listen for the blade to start singing. Give it a LITTLE more tension, turn it off, test how far you can move the blade by hand and strum it.

Try cutting something if a new blade pulls one way or the other adjust the blade guide wheels a LITTLE BIT. Tinker a little, ONE thing at a time. 

A band saw tip is to always adjust the guide rolls as close to the stock you're cutting as will clear. The less free air between guide rolls and work the less it will wander.

If it's cutting straight and starts to pull one way or the other the teeth on that side are getting dull. If you cut dirty steel it will dull the teeth quickly, sometimes immediately. I take my cup brush to dirty steel and my blades last pretty well.

Frosty The Lucky.

 

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Order more than one blade, they're cheaper that way, 3 will probably last few years. I buy several at a time through "BandSawBladesDirect". There are others online. Better still I mentioned the price online at my local industrial hardware store and they beat the deal for what they carry in stock. They increased the selection when I told them they were carrying a useless TPI blade (Threads Per Inch) some places call it "pitch" 

The rule of thumb is 3 teeth on the stock at all times. It's hard to find blades that aren't stupid too fine. About the best TPI I can find are variable pitch, they don't gall in the kerf if they aren't THE right tpi.

Darn, I'm off again! A good cut off band saw is the only power tool I'll start working and go do something else. 

Have you figured out the automatic shut off? Usually it's a little tab on the head that pushes the power switch off when the blade clears the bottom of the vise. 

Frosty The Lucky.

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Sawblade dot com  is where we got blades at my last job.

Bi-Metal blades cost more but they don't snap like high carbon blades do.

And yes, get more than one, so when you get down to one you order more.

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I ended up ordering a new bimetal blade off mcmaster carr: 8tpi seemed to fit the stock sizes I'll most likely be cutting. I'll compare prices with the site you gave Frosty and order a few more, thanks for the lead. On my smaller saw I've used for the past 4 years I always had an extra "in stock", ready to throw on when the old one broke. I'm hoping the larger blades wont break so often. On the smaller saw I was going through 3/year approximately. 

The auto shutoff works great. I did order some coolant, so we'll see if I ever use that. Right now the blade is cutting wedges, which is pretty frustrating. I tweaked the guides until they are as close to square as far as I can tell so at this point I'm assuming the problem is the old blade that was on the saw when I got it. I'm hoping the new blade will solve that issue. Otherwise, I'm hoping the problem is not worn out carbide guides. 

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Sawblade.com is the place I was thinking of when the one I recommended hit in a search. Sawblade. com carries parts for Kalamazoo saws and much more. That's the one Bigguns, thanks.

Adjusting the machine, especially the guide rolls before you have a fresh blade is a mistake. You'll have to readjust them once you get a new blade on it. It's not a major thing though, just a little more work. 

Adjust the guide rolls with a square, not by eye. Let the head down till the blade is almost at the bottom, you want the teeth below the clamp table. Lay a square on the clamp table, slide it into contact with the blade and adjust till it's parallel with the square. If it is touching the teeth there WILL be a space between blade and square, you can make it parallel but not having to interpret the gap is easier.

Frosty The Lucky.

 

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I figured I might need to re-adjust it. I wanted to see how close I could get it with the old blade while using it as an opportunity to get to know the machine.

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Now you know how it is when it's not right. Unfortunately you don't know what's not right about it. 

Best to get to know a machine that's working properly. Get it as right as you can first.

Frosty The Lucky.

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When tuning my saw I grab a scrap of large diameter square tube, it is easy to measure the cuts in the tube with a square and make adjustments. The larger the tube the more obvious the errors are.  Helps a lot when trying to dial in the last couple degrees.  Really can be frustrating when you are cutting wedges, but stick with it (after you get that new blade) Once you get it right the whole world will seem like a brighter place...

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