Band Saw Tension & Blade Breaking

[arnie]

First thing is i have not touched a band saw since jr. high and i'm 65. I bought a Skil band saw (not the best) and have broken a number of bands. Given my learning curve it has taken a few changes to get the hang of setting the tension.
My question is, is there any other reason for the bands to break at the weld? Other than the operator. Any hints you might make would be appreciated. The Saw is maybe two or three months old. Sorry the bands i have been using are 3/16 and 1/8.

THanks in advance for any help.
Arnie:icon_scra

 

[Trent Mason]

Arnie, I'm sure you'll get a lot more advice from folks that know more, but to me, it would seem that the weld would be the weakest point in the blade (I'm just guessing on that one). So I'm not surprised that it would break there. You're also using some very small blades and I'm sure it's a lot easier to snap those, rather than something like 1/2". Personally, I've only used 1/2" and 3/4" blades, mainly for resawing or rough cuts. I've had the opposite problem with those on my Grizzly. I can't get them tensioned enough. :BangHead::BangHead::BangHead: Perhaps there is a very fine line of when not to make that last turn on the tensioning knob.... :eusa_thin

 

[arnie]

Thanks Trent,
I'm using the smaller blades due to making toys for the kids and there are a lot of fine small curves. I talked to a local shop that makes bandsaw blades and they made 3 up for me using 3/16 which also broke. Considering that the material was industrial grade it surprised me.

 

[Dudelive]

Depending on just how tight a curve you are making, you might consider a scroll saw for tight turns.
It sounds like you might be turning the knob a bit too much.

Let us know what you find maybe someone else will chime in and offer other ideas.

 

[macdaddy]

To get the right tension I pluck the blade like a stringed musical insturment. The tighter the tension the higher the pitch of the sound. So I crank the pitch high and then back off a little to a middle pitch sound.

 

[Phil S]

First I would look at the wood you were cutting when it broke - look exactly were the blade was when it broke and see if the wood is glazed or burnt If so the blade is binding in too tight of curve and that will lead to breakage quickly. If the cut looks clean, either the tension is too tight or your guides too tight which will also heat and break the blade - but usually the guides would have to be extremely tight for this to be the cause.

If you find that indeed the cut looks glazed or burnt, then the curve is too tight and you might have to use a scroll saw.

Hope this helps

 

[CaptnA]

Sounds like you may have too much tension. As others have said, if small and tight, the size of the circle you are cutting can put a lot of stress on the blade, so many variables - speed of cut, thickness of wood, species of wood, and any combination of these and more can give you a fit and certainly cause/contribute to blade failure.

The woodwhisperer has a good video on tuning a bandsaw that may give you some good information. try this link -13- Bandsaw Setup/Tuneup | The Wood Whisperer
if it doesn't work, go to http://[URL="http://.woodwhisperer.com"]woodwhisperer.com[/URL] and in the search box look up tuning a bandsaw.
You said your saw isn't too good a saw. The difference in my old craftsman bandsaw circa 1981 and my new Delta of the same size and hp rating are phenominal. Nothing against any tool - but its easy to overexpect on performance.
After watching the video and reading, I decided I had some tool work to do- replacing bad tires (my fault from over tightening tension), installing better cooling guide blocks, buying some good quality blades, etc... each thing I tried made the saw better and better (now if my skills would improve as markedly)

 

[arnie]

Thanks everyone for your responses and help. I have decided to replace the old band saw after trying all your suggestions. Hopefully the new one will work out better all round for me.

Again thanks for the help.

 

[Tarhead]

When you get back to bandsawing tight turns you can try dressing the back of the blade with a stone. Ease the sharp corners and the tight turns will be smoother with less heat and stress on the blade.

 

[arnie]

Being a novice i don't understand what you mean by dressing with a stone.

 

[Tarhead]

Take a rough sharpening stone or a chunk of an old grinding stone glued to a piece of 1X2. Run the saw and round off the sharp edges on the back of the blade. Make sure nothing is smoldering in the bottom wheel well when you're finished. It'll make some sparks.

 

[ehpoole]

You can also use an old oilstone (waterstones don't fair well) to dress the back of your blade, just rotating/pivoting the stone around the rear edge of the blade to round it.

I also even out the set on my teeth by running the blade backwards (I do so by manually turning the wheels on my 18" bandsaw -- some do this under power by turning the blade inside out, then mounting it upside down). Doing so evens the set by grinding down those few teeth that stick out much further than the rest. You give up a little in terms of minimum turn radius (tightness of turn), but you gain a substantially smoother cut. To do so, you locate the oilstone to the right or left side of the blade so that it is just touching the teeth while you turn the blade backwards (teeth travelling from lower housing to upper housing).

 

[ashley_phil]

i'd recommend the next blade you buy be a timberwolf blade.

i put one on my craftsman band saw this weekend and it's a different saw!!!