My old reliable MM16 is having troubles

[Mark Katz]

This is an old 2003-era MM16, probably 1st generation (the included manual says 1st edition). I got it as a demo at a woodworking show in January 2004 and it was all set up, fully assembled, and running. It came with a Lenox Trimaster 1" blade. I brought it home, maybe tweaked a thing or two and it's been running well ever since.

Confession: I've never changed the blade (now going on 20 years). Also I keep the tension up high all the time. I did but a 1/2" Wood Slicer blade right away but its still hanging on the wall behind the bandsaw. I also never readjusted the guides after the initial setup as it seeed to be fine.

I typically use the saw for a few cuts once or twice a month - the last time I remember using it was about 2 months ago and it worked just great. I fired it up for a few small cuts yesterday and it sounded awful and is making really rough cuts. I checked and adjusted the guides (euro style) and thrust bearing but no noticeable change.

Here is a short video showing the sound that the saw is making running under no load.

https://youtu.be/b7mfTZG_GQE

And here is one showing the sound it's making while cutting.


https://youtube.com/shorts/tZYadytK6TM?feature=share

Finally, here is a picture of the cut that is being produced. Prior to this, the cuts the saw produced were very smooth.

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Not sure where to go from here. Should I bite the bullet and switch this blade out for the Wood Slicer as a test. As I said, I've never changed the blade on this saw before so it's a little daunting. On the other hand, I guess I should finally figure out how to do that. If it is the blade, I can't complain about the service it's given me.

Anything else I should look at?

Thanks, Mark

[Andrew Hughes]

My suggestion is to check the blade carefully and look for a crack in one of the gullets. They way it’s pulsing looks like a bad weld but also could be a crack forming.
Good Luck

[Richard Coers]

With that infrequency of use, I'd check how those guide bushings are rotating with the saw shut off. I have that identical saw, not unusual to have to clean up and oil the sleeve bearings in all the guide bearings. That sleeve bearing gets very dry and packs with sawdust. Blow it off and add a couple drops of lightweight electric motor oil. Could very easily also be a kink in the blade. With saw running, slowly bring up a full length stick of chalk and just let it kiss the blade right behind the teeth. That will reveal a high spot on the blade.

[Andrew Hughes]

Just wanted to add. If you do find a crack it doesn’t mean the blade is unusable just get it cut and welded by a saw service that sells bandsaw blades.
I also agree with Richard time for some maintenance on your saw. I think that’s what he’s eluding too It’s long over due.
Good Luck

[Mel Fulks]

Just wanted to add. If you do find a crack it doesn’t mean the blade is unusable just get it cut and welded by a saw service that sells bandsaw blades.
I also agree with Richard time for some maintenance on your saw. I think that’s what he’s eluding too It’s long over due.
Good Luck
That’s a good idea…when it works . Where I am they don’t fix them unless they sold it. If you are buying from a vendor that won’t
fix them ,I would move on.

[Mark Katz]

My suggestion is to check the blade carefully and look for a crack in one of the gullets. They way it’s pulsing looks like a bad weld but also could be a crack forming.
Good Luck

Thanks, Andrew. Do you think I should look for a crack with the blade on or off the machine? I could pull the blade manually a foot at a time on the machine. Am I looking for a hairline crack or something more obvious? One thouth I had is that one or more teeth are set to the side more than the others (due that possible crack) which might account for both the periodic nature of the sound and the rough cut.

I could take the blade off and examine it that way. I'm thinking my best bet, before doing anything else, is to replace the blade with that 1/2" one I've got. If that solves the problem, then I can move on. At that time I can also do the maintenance that Richard suggests.

[Andrew Hughes]

Look for the crack while the blade is under tension.
It might be hard too see if it off the saw. What I do is sit in a chair with my magnifier head set and a flashlight.
Its good to find cracks in blades. When they break during a cut it’s actually not very dangerous at all but the loud bang won’t be something you’ll soon forget.
Good Luck

[Mark Katz]

With that infrequency of use, I'd check how those guide bushings are rotating with the saw shut off. I have that identical saw, not unusual to have to clean up and oil the sleeve bearings in all the guide bearings. That sleeve bearing gets very dry and packs with sawdust. Blow it off and add a couple drops of lightweight electric motor oil. Could very easily also be a kink in the blade. With saw running, slowly bring up a full length stick of chalk and just let it kiss the blade right behind the teeth. That will reveal a high spot on the blade.

Thanks, Richard - the saw is definitely due for the maintenance you suggest. Will 3-in-1 oil work for those bearings? That's what I've got at the moment.

[Andrew Hughes]

That’s a good idea…when it works . Where I am they don’t fix them unless they sold it. If you are buying from a vendor that won’t
fix them ,I would move on.

Maybe so when everyone was eating high on the hog. These days nobody’s going to tell if cabbage fall out of your pocket they will wait for you walk away.

[Richard Coers]

3 in 1 may work, but I like a long lasting electric motor oil. 3 in 1 does make that as a specialty. I use Sid Harvey's Extendo Oil. I love the extended hose applicator for getting into tight spaces. https://www.ebay.com/itm/404542038030

[Bill Dufour]

I would look at the tires and vee belts for cracking and peeling.
Bill D.

[Erik Loza]

Mark, I hear the blade riding the thrust bearing in your first two videos. If you back the thrust bearing out a bit, the sound should disappear. Also, I see a slight pulsation in your blade. Could be a weld that’s not quite true but also could be that you have created a flat spot in the tire(s) from leaving that Tri-master under full tension for such extended periods of time.

Minimax USA used to supply a Tri-master with show pickup machines as a “cherry on the cake”, so we wouldn’t have to ship machines back to Austin but to be honest, that’s not a great all-purpose blade. If it were me, I would remove the carbide and fit that other blade you mentioned. It’s probably more suitable for everyday use. Hope this helps and you have a very special bandsaw there.

Erik

[Jim Becker]

As an owner of the same exact machine (that also came with the Trimaster) I agree with Erik's advice. Keeping that heavy band under tension for all that time could certainly be contributing to the noise for sure, too. I typically keep a .5" band on the machine for general utility use.

As an aside, my TriMaster only lasted a few years...somehow, someway, it got a "kink" in it and began to run rough so I abandoned it. IMHO, a 1" heavy band pushes things for a 16" wheel machine.

[John TenEyck]

Thanks, Andrew. Do you think I should look for a crack with the blade on or off the machine? I could pull the blade manually a foot at a time on the machine. Am I looking for a hairline crack or something more obvious? One thouth I had is that one or more teeth are set to the side more than the others (due that possible crack) which might account for both the periodic nature of the sound and the rough cut.

I could take the blade off and examine it that way. I'm thinking my best bet, before doing anything else, is to replace the blade with that 1/2" one I've got. If that solves the problem, then I can move on. At that time I can also do the maintenance that Richard suggests.


Gets some dye penetrant and spray the blade with that. Any crack will be much easier to find. FWIW, when a blade brakes it can get pretty dramatic if you run the tension very high. I had a 1" blade brake, it warned me first but I didn't heed the warning, and when it let loose it went down into the lower wheel housing and folded up like a pretzel. The sad part is it took a piece of the tire with it and scratched up a lot of paint. I learned to heed the warning. Thump, thump, thump means something's wrong, and if it didn't sound that way when the blade was new, from an imperfect weld, the blade likely has a crack in it.

FWIW, my friend has a big Grizzly BS with vulcanized tires. He leaves a 1" blade under full tension (almost 25 ksi) all the time. The saw is over 15 years old and runs great. I suspect your problem is the guides and/or blade, assuming the tires on your saw are of the vulcanized type.

John

[Tom Trees]

Obviously the blade is the first thing to eliminate
Also worth seeing if the crowned rubber on those tires has been nibbled off by the carbide blade.
It's obviously barely perceivable, as most here are still seemingly still convinced that these machines have flat tires,
(so obviously those folks reckon my Centauro 600 tire from the authorised dealer is a reject, and infact the apex of the crown should be exactly centred
for the tire to become flat due to anticlastic curvature)

Anyway....
One easy way to find out if you've removed the crown profile, is by noting beam tension will be reduced to the point of the blade refusing to cut,
not to mention set compression on non carbide blades.
If so, I strongly suggest it might be worth finding out why that camber got nibbled off, as wheel bores are at risk if ignored.

All the best
Tom

[Jim Becker]

Tom...the tires on my 2004 era MM16 are flat and not crowned. You keep coming back to this for some reason. The bands are not run in the center of the tire; rather, they have the teeth just off the tire/wheel.

[Tom Trees]

No bandsaw has flat tires Jim, that's just a misconception, or should I say obfuscation to be more specific.
(a deliberate act if you ask me)
Obviously you don't have a spare on hand to see for yourself. took me a while to actually have a proper ganda at mine!

But I suppose... it could be the case of some believing the differing sized machines have different profiles,
like the 440mm wheeled machines made from the second best manufacturers of bandsaws down the road!
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https://www.youtube.com/watch?v=GDK83aVUL9w



All the best
Tom

[Mark Katz]

Just thought I'd check in with an update. I checked over the blade with a bright light and a magnifier and didn't see anything out of the ordinary. Even the weld looked clean and smooth. I took that blade off (for the first time ever!) and checked the tires. They seemed fine, to my untrained eye and touch.

I mounted the 1/2" Wood Slicer but need to reposition the guides and thrust bearing. The upper ones were no problem but the lower ones will need some leverage to break loose the thumbscrews that lock it in place. I had to stop for the day as this 75-year old frame doesn't take kindly to crawling around on the floor. Hopefully I can get the lower guide adjusted and try running the new blade tomorrow.

Thanks for all the help, everyone.

[Jim Becker]

Tom, you have a completely different saw from a different era. But no matter, we can just choose to disagree.

[Richard Coers]

No bandsaw has flat tires Jim
Tom
No bandsaw is a very bold statement. There has never been one in the history of bandsaws? My very old Yates American with babit bearings has flat tires. It seems Centauro does too. https://sawmillcreek.org/showthread.php?296914-Flat-tires-on-a-re-saw-band-saw

[Erik Loza]

I can say with 100% certainty that every Minimax-spec Centauro ever made has totally flat tires. Regardless of size. Not mildly crowned, not slightly round-overed, but totally flat. I’ve installed many of them!

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Maybe vintage machines were different? I have no idea.

Erik

[Jim Becker]

Thanks, Erik. That was my understanding, too, from hanging out with you folks "back in the day". :)

[Tom Trees]

Tom, you have a completely different saw from a different era. But no matter, we can just choose to disagree.
Completely different, yet Sam Blasco tracks the Centauro made MM16, and the newer ACM formula saws the exact same as is suggested for these machines.
I think we're agreed on that last part. :)


No bandsaw is a very bold statement. There has never been one in the history of bandsaws? My very old Yates American with babit bearings has flat tires. It seems Centauro does too. https://sawmillcreek.org/showthread.php?296914-Flat-tires-on-a-re-saw-band-saw
My saw with vulcanized tires had a flat profile on them also.
Though I dressed them as such, they didn't come like that, for good reason, as you can read on page 20
https://www.ukworkshop.co.uk/threads/centauro-400-ssp-bandsaw-does-anyone-have-a-manual.141846/

" MAIN TROUBLE AND RELATIVE REMEDIES "


The blade moves very far back when it receives the cutting force
- Insufficient flywheel seal convexity, notify the technical service of the area dealer.


I can say with 100% certainty that every Minimax-spec Centauro ever made has totally flat tires. Regardless of size. Not mildly crowned, not slightly round-overed, but totally flat. I’ve installed many of them!

Maybe vintage machines were different? I have no idea.

Erik


As mentioned Erik, I dressed my tires to make a totally flat profile before, and not just once to be sure,
aswell as considering the edge of the wheel had some importance in regards to acting as a crown, and making sure it was consistent,
so experimentation thereafter in regards to wheel depth in chassis.
All those things did nothing in regards to having anywhere satisfactory beam tension, i.e the blade was refusing to cut.
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Edge chamfering thereafter for consistency
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And some wheel depth experimentation after levelling the machine beforehand
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I can post some more about that, if there's a misunderstanding or perhaps some scrutiny instead.

So my point being, if it is indeed true what you say about these snap on tires seemingly
having a visually flat profile, that doesn't mean it acts as such.

And anticlastic curvature doesn't account for the cambered apex, which is offset by 1mm,
on these flat profiled wheels.
I can't take a screenshot of the Centauro wheels, but those are also machined flat from what little I've seen of them.
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One possible reason for this I guess, is the face of the wheels throwing things off when using a straight edge against them.
I've maxed out my picture count, but can show how much times I questioned if I might have been off by possibly one degree perhaps,
but then again, I did muck about for a very long time trying various adjustments, etc..

All the best

Tom