Bandsaw blade twist

[Sandy Syring]

I just installed a new bandsaw blade and while attempting to tension it properly, I could not. I would get it to the point of running with minimal wobble, then suddenly it would wobble significantly. When I unfolded the blade I did notice what appeared to be a small bend in the blade. When I rotate the blade by hand there is a very noticeable point where the back edge of the blade twists out to the right. Don't know if it's a me problem, a Bandsaw problem, or a blade problem. I've attached three pics to demonstrate the issue I see with the blade. In the first pic the block of wood is set against the blade. You can see in the second pic the amount of twist. In the third pic you can see how much the block was moved by the blade twist. Any thoughts/help would be appreciated.

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[Michelle Rich]

if your bandsaw was running fine before the blade change, I'd guess it is the kink in the blade.

[John K Jordan]

This certainly sounds to me like the blade is warped, especially since you can see a twist while rotating the blade by hand. Does the obvious twist line near the kink you noticed.

In my experience a kink of any kind is the end of a bandsaw blade, even a relatively small one. If you lay the blade down flat on, say, a flat concrete floor, can you see any warp? Also, if you rotate the blade by hand (or watch through a window if your saw has one) does the blade track in one spot on the tire or does it move forwards and back? (I suspect it tracks ok or you would have noticed this while running.)

Since this is a new blade perhaps it could be exchanged if it is bad.

I would check that the tension is set high enough. (Then set the guides properly, of course!) If the blade runs fairly smoothly for a while then suddenly starts to wobble (flutter?) for a while, insufficient tension is suspect, although a higher tension probably won't fix a warped blade.

You said you could not get it to tension properly. What method, deflection, flutter, tension indicator on saw, separate tension gauge? There is a lot of controversy over how and how much to tension. I personally use a tension gauge to set the tension of a new blade and to "calibrate" the tension needle and marker built into my bandsaws. For me this removes any doubt. However a tension gauge is expensive. You can measure the tension just as well with just a digital caliper and a couple of clamps. Here are some earlier messages about how to do this:

http://www.sawmillcreek.org/showthread.php?250388-Bandsaw-blade-tension&p=2640833#post2640833

http://www.sawmillcreek.org/showthread.php?251853-bandsaw-tension-guidelines&p=2659282#post2659282

The proper tension of course will not fix a warped or kinked blade, but will eliminate one variable factor.

JKJ

[Erik Loza]

Kinked blade. Just get a new one.

Erik

[glenn bradley]

Kinked blade. Just get a new one.

Erik

+1
Just that easy.

[Sandy Syring]

Thanks for the response and links. In answer to your questions, yes, the twist occurs at the location of the kink. I use the flutter method of tensioning my blades. I could not get the fluttering to stop for any length of time regardless of the tension applied. The blade is tracking correctly on the tires. I have contacted the merchant that I bought the from and asked to have the blade replaced. I'm hoping they will agree however I purchased the blade in late January and just got to installing it last night.

[lowell holmes]

Thanks for the response and links. In answer to your questions, yes, the twist occurs at the location of the kink. I use the flutter method of tensioning my blades. I could not get the fluttering to stop for any length of time regardless of the tension applied. The blade is tracking correctly on the tires. I have contacted the merchant that I bought the from and asked to have the blade replaced. I'm hoping they will agree however I purchased the blade in late January and just got to installing it last night.

I would probably buy a new blade to get the saw running and take the damaged blade back to the dealer it came from for replacement. It doesn't hurt to have a replacement blade on hand.