Bandsaw blade keeps falling off!

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bsshog40

bsshog40

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Joined
Oct 2, 2018
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Omaha, Tx
So I have a 17" grizzly bandsaw. I never had any problems with it in west tx. Since we moved back here to E.Tx., I've used it a few times but the last couple times I've tried to cut wood, the blade keeps coming off the wheels. The rubber ring under the blade is sliding off also. I have rechecked and adjusted my stopper and guide wheels and checked tension. I have maybe 1/4" slack. I even bumped the tension just a little but the blade still keeps coming off. Any suggestions?
Bobby
 
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Sounds to me like the top wheel is out of plane (no longer aligned and in the plane the lower wheel and blade need to be on).

There will be an adjustment above or below the center of it on the back.

Check out this video where Alex Snodgrass is a guest on the Wood Whisperer YouTube Channel. He goes over the whole process.

 
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d_bondi said:
Sounds to me like the top wheel is out of plane (no longer aligned and in the plane the lower wheel and blade need to be on).

There will be an adjustment above or below the center of it on the back.

Check out this video where Alex Snodgrass is a guest on the Wood Whisperer YouTube Channel. He goes over the whole process.

Click to expand...
I will watch this. Thanks
 
Alright, so I watched the video and got manual out and readjusted all my blade guides, centered the blade on my wheel and set to about 1/4" tension. This is a 1/4" blade. Everything seems to be ok for a bit and then looking thru my inspection window, it looks like the blade is trying to jump forward occasionally. I see no wobble at all in the wheels. See video below of what is happening.
 
It looks like you have the blade centered on the wheel.

Per the Alex Snodgrass method/video (that I use and stand by), you want the bottom of the gullet of the teeth centered on the wheel. In other words, in my opinion, you need to move the blade back a bit.
 
d_bondi said:
It looks like you have the blade centered on the wheel.

Per the Alex Snodgrass method/video (that I use and stand by), you want the bottom of the gullet of the teeth centered on the wheel. In other words, in my opinion, you need to move the blade back a bit.
Click to expand...

@bsshog40 Aye, you generally want the gullet of the teeth to be closer to centerline, than to have the blade entirely centered. This ensures that the cutting edge of the blade is very stable. If you center the blade, then the cutting edge actually hangs out front a bit, and since the wheel has a curved surface, this allows the cutting edge of the blade to wander. I've been following the Snodgrass method for years now and its kept my cutting edge stable.

Regarding the blade coming off the wheel...how do you tension your blade? There are a variety of techniques. Using the gauge in the bandsaw is usually not very effective. I've been using the "flutter" method lately myself. If you search for some videos, you'll find some that are very good. The general idea is to tighten the blade, then turn the bandsaw on and look for a flutter in the blade. If there is none, you are probably too tight, so back it off until you see a slight flutter. When you see the flutter, tighten just until the flutter disappears and does not reoccur. That should get you to tight enough but not too tight (which can start wearing the wheel unnecessarily.)
 
I'll adjust the wheel again and try that.
As to tension, I tightened the blade where I had 1/4" play behind the top wheel where snodgrass showed. I also tried the flutter method but I still have flutter and the blade doesn't give that much play. I'm afraid I might snap the blade. Should I take it to "no flutter" and see what happens?
So I recentered the gullet on the wheel. 10 seconds of running and this happens.
1000015753.jpg
 
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A couple things. First get rid of those tires. Grizzly had problems with their original urethane tires for some time. The tire should never ever slide right off. Unless there is tremendous heat built up because of blade slippage.. If blade is slipping then tires are not doing their job. I never did like urethane tires. I prefer rubber tires. Those look pretty thick and flat. A tire should have a crown to it. I understand the Blue Max urethane tire works well with that saw. I have no experience. There is and always will be one of those old adages you do not need to glue urethane tires on but others say different. They should be proper size and and when installed may need a little heat to install them. Then you know they are correct. You could try gluing them but to me I would replace them before buying new blade.

The next thing it is important the wheels are parallel to begin the tune up. The blade could have an offset in it from prior use or from heat because of slippage on tires so you may need to replace it as well. This is correct to center blade on tire with the back of the gullets in the center. yes on no flutter. Those gauges on bandsaws are only guides. Alexe's tutorial is very good. Those 1/4" blades and smaller are not easy blades to use and keep running true on large saws like that. Good luck. My two cents.
 
Ok, so I washed my tires. The blade is staying on but I haven't applied any pressure like a cutting a board yet. I'm watch my blade and it's straight for a few seconds, then flutters a little, then straightens up again and flutters again. Maybe a bad blade. I have a spare blade that was new but is rusty now from when I had my tools in storage for a year and a half. Not sure if I can trust that blade now.
 
bsshog40 said:
I'll adjust the wheel again and try that.
As to tension, I tightened the blade where I had 1/4" play behind the top wheel where snodgrass showed. I also tried the flutter method but I still have flutter and the blade doesn't give that much play. I'm afraid I might snap the blade. Should I take it to "no flutter" and see what happens?
So I recentered the gullet on the wheel. 10 seconds of running and this happens.
View attachment 385609
Click to expand...
So, sometimes the tires are bonded to the wheel. I can't tell if I am seeing and old bead of glue on the wheel there? Does it look like the previous bond has broken? It might just take rebonding the tire to the wheel, to keep it in place.

As for flutter, before you try that, I guess, I would make sure you find and watch a few videos on how people actually do that, as they will usually talk about appropriate tension and all that. Regarding play in the blade....you say you have 1/4"? As far as I remember, Snodgrass says NO MORE than 1/8" play. If you have 1/4" play I suspect your blade is probably a bit too loose still. I would still recommend watching some vidoes on the flutter technique, so you have a full grasp of how it is intended to work, and how to know when you have the tension right. There are different kinds of blades as well, and tensioning say a metal cutting blade (which I use for cutting hard resins and things like TruStone) because they have more teeth and have less risk of chipping or breaking brittle blanks like that, and tensioning them is not necessarily the same as tensioning a wood cutting blade.

Once you have a good handle on how the flutter method is done, I think you'll be able to dial it in pretty readily. That tire, though...popping off like that, is kind of crazy. I don't know if that particular brand of bandsaw is one where you usually glue the tier in place or not, but its worth checking if it is and doing so if required.
 
bsshog40 said:
Ok, so I washed my tires. The blade is staying on but I haven't applied any pressure like a cutting a board yet. I'm watch my blade and it's straight for a few seconds, then flutters a little, then straightens up again and flutters again. Maybe a bad blade. I have a spare blade that was new but is rusty now from when I had my tools in storage for a year and a half. Not sure if I can trust that blade now.
Click to expand...

I suspect its just not tensioned enough. Those little flutters, are what the flutter method of tensioning is all about, and once you dial it in the blade should be rock solid stable, but not over-tensioned.

I guess it could be possible, that a bend in the blade might be causing the flutters. If that is the case, you probably want to replace the blade, but, I would see if you can find the bend(s) first to make sure. If you do not have any, then its likely you just don't have enough tension. I was pretty timid when I first got my bandsaw, and never had it tensioned tight enough. I had occasional flutters, and they affect the cut. I don't remember how I came across the method in the first place...I think it was just a YT video that auto-played after some other bandsaw maintenance videos I was watching. I then watched more, got a real feel for it, and since learning it, my blades no longer flutter, are very stable and strait, and cut a heck of a lot better than they did early on.
 
I've been watching videos on tensioning the blade. What bothers me right now is the guage on this saw maxes out at 8. Right now that guage is on 7. I never had any problems with this saw before we moved and I know that guage at most was around 5. I know you can't really depend on the guage but almost maxing it out makes me nervous about snapping the blade.

To add: grizzly has a bundle pack of 3 different blades for about $55. I think I'm just gonna go back to a 1/2" blade and hopefully that will fix my problem. The 1/4" blade I have on there now is about 4 yrs old. Still not used that much but sitting in storage for a year may not have done it any good.
 
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bsshog40 said:
I've been watching videos on tensioning the blade. What bothers me right now is the guage on this saw maxes out at 8. Right now that guage is on 7. I never had any problems with this saw before we moved and I know that guage at most was around 5. I know you can't realky depend on the guage but almost maxing it out makes me nervous about snapping the blade.
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You do know bandsaw blades do stretch right. Just like scrollsaw blades which I have dealt with over the years.. Blades on a bandsaw are lot trickier than a solid blade on a tablesaw. Small blades are tougher to keep tuned because as with any blade heat will cause strange things to happen. When a blade gets hot it expands and when it cools it shrinks. You keep tightening a blade that is hot and when it cools and shrinks you now put more stress on that blade. This can cause micro cracks in the blade and will break sooner. Alot of this has been overcome by different blade metal makeup and I will not get into all that. This is why they recommend to release tension your blade when done using a saw. It also can make permanent indentations in the tires either type. and can cause vibrations later because heat melts. If you have your saw dialed in and keep the guards close to your work you should not get fluttering.
 
jttheclockman said:
You do know bandsaw blades do stretch right. Just like scrollsaw blades which I have dealt with over the years.. Blades on a bandsaw are lot trickier than a solid blade on a tablesaw. Small blades are tougher to keep tuned because as with any blade heat will cause strange things to happen. When a blade gets hot it expands and when it cools it shrinks. You keep tightening a blade that is hot and when it cools and shrinks you now put more stress on that blade. This can cause micro cracks in the blade and will break sooner. Alot of this has been overcome by different blade metal makeup and I will not get into all that. This is why they recommend to release tension your blade when done using a saw. It also can make permanent indentations in the tires either type. and can cause vibrations later because heat melts. If you have your saw dialed in and keep the guards close to your work you should not get fluttering.
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Thanks John. I always take the tension off my blades with both my bandsaws. I edited to my last post, in case you missed it.
 
bsshog40 said:
I've been watching videos on tensioning the blade. What bothers me right now is the guage on this saw maxes out at 8. Right now that guage is on 7. I never had any problems with this saw before we moved and I know that guage at most was around 5. I know you can't really depend on the guage but almost maxing it out makes me nervous about snapping the blade.

To add: grizzly has a bundle pack of 3 different blades for about $55. I think I'm just gonna go back to a 1/2" blade and hopefully that will fix my problem. The 1/4" blade I have on there now is about 4 yrs old. Still not used that much but sitting in storage for a year may not have done it any good.
Click to expand...
Have to say on a 1/4" blade at a tension of over 7 on any guage is way too high. Recommended 15,000-20,000 psi for carbon steel blades and 25,000-30,000 for bimetal blades. And this is why those gauges are basically a guide. Get one of those tension gauges for bandsaws if concerned about tensions. They clip on the blade. You can buy aot blades for the price of a good quality one though. :)
 
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jrista said:
@bsshog40 Aye, you generally want the gullet of the teeth to be closer to centerline, than to have the blade entirely centered. This ensures that the cutting edge of the blade is very stable. If you center the blade, then the cutting edge actually hangs out front a bit, and since the wheel has a curved surface, this allows the cutting edge of the blade to wander. I've been following the Snodgrass method for years now and its kept my cutting edge stable.

Regarding the blade coming off the wheel...how do you tension your blade? There are a variety of techniques. Using the gauge in the bandsaw is usually not very effective. I've been using the "flutter" method lately myself. If you search for some videos, you'll find some that are very good. The general idea is to tighten the blade, then turn the bandsaw on and look for a flutter in the blade. If there is none, you are probably too tight, so back it off until you see a slight flutter. When you see the flutter, tighten just until the flutter disappears and does not reoccur. That should get you to tight enough but not too tight (which can start wearing the wheel unnecessarily.)
Click to expand...
So if I go back to a 1/2" blade, would I center that blade or set the blade gullet to the center also? That wheel is only about 1" or so of space.
 
I am far from a bandsaw expert and have trouble with my saw staying true for extended periods of time. I think that's due to my second hand machine and the user together. If I spend time really going after perfect then it runs well for a while and will gradually "loosen up" a little and require some retuning after some use. To be fair to the machine and user, I have the hardest time with this when I'm really pushing the machine making bandsaw boxes in the shape of apples with a 1/8" blade.

That said, I do tend to think a couple of the other posters could be on to something and you ought to think about replacing the tires. I wonder if the existing ones have a little slack in them and they are part of the problem. I replaced mine a while back and it has definitely helped my machine. You might need to clean the wheel with a little denatured alcohol or something before installing new ones too. Your photo makes me think the tire wants to slip when under pressure for tension and cutting together.
 
Blades are an expendable (or consumable) item. You will need replacements going forward. Get some now, and go for great quality. Much the same discussion for tires. replace them, and if you want to diagnose, replace one at a time. That will ID the culprit. You should be up and running as a result.
 
I bought my bandsaw new maybe 5-6 yrs ago. I've never done any resawing on it and most cutting is just small pine wood projects, pen blanks and a few small hardwoods. I'm beginning to think that the year in storage, which were not climate controled, probably didn't help anything much. I will probably just go ahead and get new blades and tires, hopefully next month.
I really appreciate all the responses my friends! Y'all have been very helpful!
 
bsshog40 said:
I bought my bandsaw new maybe 5-6 yrs ago. I've never done any resawing on it and most cutting is just small pine wood projects, pen blanks and a few small hardwoods. I'm beginning to think that the year in storage, which were not climate controled, probably didn't help anything much. I will probably just go ahead and get new blades and tires, hopefully next month.
I really appreciate all the responses my friends! Y'all have been very helpful!
Click to expand...
You won't regret it. It is one of those things that gets overlooked many times. The big thing about rubber tires and urethane tires is basically the ease to clean. Hard plastic is easier to clean because with rubber bits of saw dust can become embedded,. There are 2 sides to which is better but new ones will make a difference.
 
bsshog40 said:
So if I go back to a 1/2" blade, would I center that blade or set the blade gullet to the center also? That wheel is only about 1" or so of space.
Click to expand...

Centering on the gullet is what you need. If you center on the middle of the blade, then the teeth will wander and you won't get optimal cuts. Centering on the gullet ensures that the crown of the tire peaks at the portion of the blade that will ensure the teeth remain stable during a cut. So always to the gullet.

Regarding tension, your tire did come off. I wonder if that somehow changed things enough to affect tension. I would certainly try a different blade and see how things go. When testing for flutter, you don't want the blade to already be at a high tension, I think if you well overtension it, you can cause flutter as well. So start with a tension that keeps the blade on the tire safely, but not fully tensioned. Then turn the bandsaw on. You will likely see flutter, and you then start increasing the tension on the blade until the flutter disappears. When it disappears stop, and you should be tensioned well enough that your blade is stable and will give you a clean, strait cut.

This is a short video where he shows how to use the flutter method to tension a blade, on what I think is a grizzly:


He de-tensions it a bit at first, to introduce flutter, then re-tensions it until the flutter is gone. Then, finally, once he is sure the blade is stable, adds a 1/4 turn to tighten it just a smidge more. This is pretty much the procedure. Key thing being, de-tension a little first, until you first see flutter, then re-tension to eliminate it. It is possible to over-tension, and sometimes you can see some flutter when you get too tightly tensioned. The other key thing here is that additional 1/4 turn to make sure your blade is indeed well-tensioned (if you don't do that, you might still have the occasional flutter.)

When you back tension off and see a lot of flutter like he did, then you know for sure, you definitely don't have enough tension. You don't necessarily need to back it off quite that much, but you should see (and often hear the vibration of) flutter before you start re-tensioning.
 
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Several months ago I had a blade that started doing that kind of thing. After a close inspection in the blade I found a crack in the blade between two teeth. A new blade fixed it right up. - Good Luck I hope you are successful in diagnosing and fixing the problem. - Dave
 
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