How do you know when bandsaw blade is dull?

[southernclay]

Bought a bandsaw at an estate sale a while back and it came with many extra blades, none in packaging.

Is there an easy way to tell if the blades are still sharp enough to use without putting them each on the saw and trying them out? I've looked them over for rust, damaged teeth etc.

It's a nice assortment of sizes. My first thought is buy new of the couple of sizes I think I will use most of but can't seem to find the answer to the question out there so got curious.

Thanks!

 

[robutacion]

Bought a bandsaw at an estate sale a while back and it came with many extra blades, none in packaging.

Is there an easy way to tell if the blades are still sharp enough to use without putting them each on the saw and trying them out? I've looked them over for rust, damaged teeth etc.

It's a nice assortment of sizes. My first thought is buy new of the couple of sizes I think I will use most of but can't seem to find the answer to the question out there so got curious.

Thanks!

Is not that difficult to see if a bandsaw blade is blunt or not, you just need a very close up look at the teeth, you can take some macro pics and show them here or, you use some magnifying glass tool to allow you to see clearly the very tip of the teeth.

From experience I can tell if a tool/blade is sharp, with my eyes closed, I feel the edge and you can tell however, if you are not very experienced, which we all were in our beginnings, the best way is to actually use it.

Why do I say this...??? well, from factory if the teeth feel sharp, the blade will cut well however, if the blade/tool, was sharpen by someone without much experience, the edge may feel sharp but, it would be a nightmare to cut anything with its because, not all sharpening and thee setting, is the same.

Some blades when need sharpening also need re-setting the teeth, this is called "racking", the angle and sequence of the left, right and centre can vary but, if the teeth were set too far out, in the wrong sequence and sharpen at the wrong angles, you will have all sorts of troubles and "grabbing" will be the one that can hurt you, pretty bad...!

I reckon, the easiest way for you would be looking at each blanks to see if the teeth look all in the same condition and then, take a good close up photo of one section, that will show half a dozen teeth, show that here, I and some other members, will be able to tell you if they are OK or not...!

Cheers
George

 

[lwalper]

If it feels sharp (like, easily hooks the skin on your finger with gentle pressure) it's probably sharp enough to use. Throw one on the machine and see what it does.

 

[Sylvanite]

I was going to say that if you get blood on blade when you handle it, then it's sharp.

 

[JD Combs Sr]

I would use the finger nail test on any spare blade I needed to test. Rub the top of one of your finger nails "lightly" against a few teeth. A sharp blade will generally dig in and scratch your nail. Dull blade teeth will mostly just slide across your nail. Works good for table and miter saw blades also.

 

[southernclay]

I was going to say that if you get blood on blade when you handle it, then it's sharp.

How hard should I squeeze? : )


Thanks for the quick replies, that was my gut feel but definitely not enough experience to trust my gut yet. Although it's getting bigger does that count?

Most look and feel pretty good. Like this.


There are some like this second one that just look ok but have several similar size in good shape.

Then a couple like the third that have a little surface rust too so not sure about that.

Overall 10 extra blades the larger ones look good and some of the smaller do as well so should be able to do a few various jobs with them.

 

[southernclay]

I would use the finger nail test on any spare blade I needed to test. Rub the top of one of your finger nails "lightly" against a few teeth. A sharp blade will generally dig in and scratch your nail. Dull blade teeth will mostly just slide across your nail. Works good for table and miter saw blades also.

Great point thanks!

Btw, got the adapters, just what I needed so thanks again!

 

[robutacion]

None of those blades look new, far from it, the one with the least use is the one on the third pic but still, not that sharp.

To actually verify if a bandsaw blade is OK or not, depending on how it looks, you can very quickly put it on the bandsaw and not worry about fence and any other stuff that you have to remove to replace the blades. Most bandsaws, will allow you to remove the blade you've got there and instal the one you want to test, tension it slightly and grab a piece of board that to you use to make a single straight cut, free hand, if is blunt, you will know straight away...!

Now, there are times where the blade is new or sharp and doesn't cut straight with the fence, 95% of times, has nothing to do with the blade but, incorrect adjustment on the table, guides and or many other adjustable locations...!

Cheers
George

 

[Lucky2]

For the little amount of time it takes to load/unload another blade on your saw, I think that that's what you should do. Then after doing some practice cuts, you will know yourself if the blade is sharp enough to do the cutting you want to do. Don't take our word as gospel on the sharpness of the blades that "YOU" are about to use, none of us want to take on the responsibility of you cutting yourself. Plus, by trying each blade, you get familiar with what each of them are best at. Good luck
Len

 

[jttheclockman]

Everyone of those blades you have shown are used. The ones on the right hand side photo look dull. The teeth should come to a point and those look rounded over. You can always have them sharpened. You would need a place that knows what they are doing though. The problem too is though it may cost more than new ones. Seperate the blades and use the ones you need and like others have said you will know if they are sharp after a few cuts. Now if you are rough cutting blanks so be it. They may do you well just the way they are.

 

[southernclay]

Thanks all. This has been on the list for a while but saw time is rare. Shop is in the basement and mostly only go down when kids are asleep. Great advice, intimately it is as expected to put em on and see how the cut but was curious of other techniques. Thanks again!

 

[Charlie_W]

Warren,
If the blade wanders and will not cut on your line, it is dull. If you feel you have to push hard against the blade to get it to cut, it is dull. This can lead to you getting injured. If you are pushing your work and the blade comes out of a cut your hand will move forward near or into the blade.

If you can pick up a new blade locally, buy the new blade, put it on and this will be your standard as to whether the others are sharp.
Sometimes a blade will loose it's sharpness on one side. the teeth should feel the same on both sides of the blade.

Hope this with all the other great advise helps.

I would rather throw away a dull blade than throw away part of my finger.

 

[southernclay]

Thanks Charlie! I'm ordering a couple new blades today along with two blades for a little 10" craftsman I have. I like the idea of having a good comparison first since I have cut very little with the saw and only with the blade currently installed. The sizes that came with the saw are so varied it will be nice to have them if they still cut for a very rare use.

 

[LeeR]

Google "Alex Snodgrass Bandsaw" and watch his YouTube from a wood show. He demonstrates how to place blade on wheels, tensioning, and most importantly for me personally, how to set bearings so they are NOT touching blade when blade is moving. Friction causes heat which can eliminate the tooth set. By following his advice, my bandsaw operation improved dramatically, and my resawing is so much better.

Oh what the heck, here is the link ...

https://www.youtube.com/watch?v=wGbZqWac0jU

 

[duncsuss]

Google "Alex Snodgrass Bandsaw" and watch his YouTube ...
https://www.youtube.com/watch?v=wGbZqWac0jU

The only thing better than watching this demonstration of how to tune a bandsaw is watching it again ... and again ... and again ... :biggrin:

Seriously, I change the blade on mine so infrequently that I watch this video twice before doing it.

 

[Charlie_W]

What type and brand of blade to buy is another huge topic and you should find some threads for that. ...main thing is buy quality. A thicker blade is light years better than the flimsy blade you will get at your big box store.

Buy quality and smile when it cuts great!

 

[southernclay]

What type and brand of blade to buy is another huge topic and you should find some threads for that. ...main thing is buy quality. A thicker blade is light years better than the flimsy blade you will get at your big box store.

Buy quality and smile when it cuts great!

Researched that and bought a few blades from Timberwolf today, extremely helpful folks! I just had a blade break while in operation on a small 10" craftsman I have just for cutting blanks into two pieces when doing batches. Blade was 3-4 months old with little use and tension not too tight, bought at a big box store and won't do that again. :biggrin: Got my heart rate up a bit

That's what got all of this going and off the backburner.

 

[Charlie_W]

What type and brand of blade to buy is another huge topic and you should find some threads for that. ...main thing is buy quality. A thicker blade is light years better than the flimsy blade you will get at your big box store.

Buy quality and smile when it cuts great!

Researched that and bought a few blades from Timberwolf today, extremely helpful folks! I just had a blade break while in operation on a small 10" craftsman I have just for cutting blanks into two pieces when doing batches. Blade was 3-4 months old with little use and tension not too tight, bought at a big box store and won't do that again. :biggrin: Got my heart rate up a bit

That's what got all of this going and off the backburner.

My experience over the years...since the early seventies, is that when a bandsaw blade breaks, it just plain stops...dead in its tracks. Never had one jump out and try to get me. Makes a bunch of noise, kicks up some dust and wakes you up!
Good call on the timber wolf!

 

[southernclay]

My experience over the years...since the early seventies, is that when a bandsaw blade breaks, it just plain stops...dead in its tracks. Never had one jump out and try to get me. Makes a bunch of noise, kicks up some dust and wakes you up!
Good call on the timber wolf![/quote]

Yep! Exactly what happened to me. That was my first break. Fight or flight kicked in hard, since I couldn't punch the bandsaw in the face I ducked:biggrin:

I've learned a lot of this thread, I knew the real answer was to put some blades on and try them out safely but the info that has come out of it makes me glad I asked, even for future searchers to see some of the tips and especially what typically happens when blades do break.

This blade was 3/8, I can only imagine the h@!! that breaks loose with a 1" blade!

 

[Charlie_W]

Once a blade breaks, it instantly looses contact with the drive wheel as it is no longer tensioned. Your blade also has hundreds of teeth which grab onto the bandsaw doors, the narrow spaces on the straight aways. Sort of like a blade brake!
Keeping your blade guard down near your workpiece is always the safest route.
I have a friend who cuts lots of big bowl blanks. He leaves the blade guard up high on his 14" height of cut Laguna...makes me nervous. I pull it down when I use it.

 

[reddwil]

Just bring them to me. and Ill let you know sometime next year if they were dull or not.

 

[southernclay]

Google "Alex Snodgrass Bandsaw" and watch his YouTube from a wood show. He demonstrates how to place blade on wheels, tensioning, and most importantly for me personally, how to set bearings so they are NOT touching blade when blade is moving. Friction causes heat which can eliminate the tooth set. By following his advice, my bandsaw operation improved dramatically, and my resawing is so much better.

Oh what the heck, here is the link ...

https://www.youtube.com/watch?v=wGbZqWac0jU

Lee I was able to take the time to today to watch it, amazing video, thanks again for posting it. In the next couple weeks will watch it again prior to playing with the blades.