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Can someone diagnose this Bandsaw?

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Forum topic by StDane posted 03-31-2020 11:47 PM 1210 views 0 times favorited 57 replies Add to Favorites Watch
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StDane

20 posts in 1571 days


03-31-2020 11:47 PM

I have a Steel City 14” band saw. It has started making crazy cuts. As you stand at the saw, no matter what size blade, how tight, loose or just right I tension it, or how carefully I set the guides, it cuts hard to the left and no amount of trying to turn the work against the curve will allow you to straighten it out. The blade is perpendicular to the table. The blade will try to go left and take it to the point of locking up because of the twist in it from trying to straighten it out. There are couple of pics of cuts in a board, plus how it cuts in a crazy compound curve pattern in a thick piece of wood when just trying to make a simple straight cut. One possibility is that on the upper wheel the gullets are centered on the crown, but not so on the lower wheel. I don’t think this should be an issue, but hey, I obviously don’t know anything at this point.

The guides can’t get set quite as close as I thinks they should be, but that shouldn’t matter in a straight-on cut. The instant the blade touches the wood it starts to curve off. I have tried different settings on the thrust bearings to no avail.

Saw is 100% dysfunctional right now. Any ideas are welcome.

Thanks
Dan


57 replies so far

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jkm312

20 posts in 140 days


#1 posted 04-01-2020 12:17 AM

Check to make sure your blade is centered on your wheels and they are co planer. The picture 2nd from the bottom is centered, the bottom picture the blade is not by the looks of it. You will need a straight edge you know is straight or perhaps an aluminum level that hasn’t been dropped yet and dinged up the corner. Don’t ask me how I know about that one.

If you google Alex Snodgrass you will find some you tube videos that will teach you a lot about tuning band saws.

Last bit of advice. Relax, it’s a machine and they all need care from time to time. You got this.

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Andybb

2751 posts in 1340 days


#2 posted 04-01-2020 12:27 AM

Hard to tell which picture is of the top or bottom wheel. The bottom picture is extremely not right regardless if it’s the top or bottom wheel. Is the bottom picture your upper wheel? The wheels need to be parallel but don’t need to be co-planer but that is very extreme. Something is not right.

Start with a sharp blade and the Snodgrass tune-up including the guides then report back. As Snodgrass says, remove the table and back the guides off before mounting the blade. The BS is probably the most complex tool to set up as there are so many variables. Is the blade dull?

I can think of a few causes. Show us a picture of the saw. Can you tension the blade properly? Does the top wheel attach to one of these? They are usually pot metal and break easily.


Check to make sure your blade is centered on your wheels and they are co planer.

- jkm312

Sorry but no, that is not the case and Snodgrass says so in his video. They do not need to be co-planer. Trust me on this.

-- Andy - Seattle USA

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Aj2

2965 posts in 2534 days


#3 posted 04-01-2020 12:50 AM

That looks like the way a dull blade cuts. If that’s a woodslicer blade they dull pretty fast esp if your wood is wet or the exotic nasty stuff.
Good Luck

-- Aj

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MrUnix

8005 posts in 2935 days


#4 posted 04-01-2020 01:08 AM


- StDane

If that is your upper wheel, your tracking is way off.

Cheers,
Brad

-- Brad in FL - In Dog I trust... everything else is questionable

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TheSnekkerShow

6 posts in 121 days


#5 posted 04-01-2020 01:10 AM

If the blade tracks fine before you start cutting, but starts moving hard to one side after you start cutting, it’s likely a blade issue. It’s tough to see if there’s any pitch buildup, but that will cause the blade to twist because the pitch hits the wood before the side of the tooth. Since it’s a set-tooth steel blade, they’re also very sensitive to hitting anything metal on the sides because it ruins the set.

Have you aligned your fence to the blade yet? If so you could test with a thin piece of plywood or MDF to verify setup. If your fence is perfectly aligned to the blade and you cut in slowly only an inch or so before stopping the saw and not moving the wood, the back of the blade should not touch either side of the kerf.

I nearly ruined a $140 carbide-tipped Laguna Resaw King by starting the saw before lifting the tensioner, and then I stepped on the brake in a less-than-ideal reaction. The brake caused the blade to slip off the wheel and scrape against the side of the table, and I had to send it back for sharpening to get it to track right again.

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Andybb

2751 posts in 1340 days


#6 posted 04-01-2020 01:35 AM

If that is your upper wheel, your tracking is way off.

Cheers,
Brad

- MrUnix


+1 Why is it tracked so far back on the wheel? Before you do anything center the blade or the gullet on that wheel. I assumed the bottom pic was the bottom wheel but probably not.

-- Andy - Seattle USA

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Foghorn

463 posts in 123 days


#7 posted 04-01-2020 01:36 AM


Check to make sure your blade is centered on your wheels and they are co planer. The picture 2nd from the bottom is centered, the bottom picture the blade is not by the looks of it. You will need a straight edge you know is straight or perhaps an aluminum level that hasn t been dropped yet and dinged up the corner. Don t ask me how I know about that one.

If you google Alex Snodgrass you will find some you tube videos that will teach you a lot about tuning band saws.

Last bit of advice. Relax, it s a machine and they all need care from time to time. You got this.

- jkm312

I used to subscribe to co-planer as well until seeing both the Michael Fortune and Snodgrass tips. They both say it’s not required and a little offset is actually a benefit. Edit: Andybb already covered it. :)

-- Darrel

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CaptainKlutz

3027 posts in 2231 days


#8 posted 04-01-2020 02:02 AM

+1 dull blade(s)?

+1 AndyBB comments on pivot bracket in tension assembly.

Check the location of blade on the top wheel. If should be same on front and back, relative to the table.
Have seen where the casting holding the pivot pin on tensioner broke and the wheel was tilted slightly. It should be same distance to sheet metal cover on both side. The bracket can rest on the lower housing, which makes the failed pivot bracket hard to see; until you use enough tension to break the bracket all they way.

Best Luck!

-- If it wasn't for bad luck, I wouldn't have no luck at all, - Albert King - Born Under a Bad Sign released 1967

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Andybb

2751 posts in 1340 days


#9 posted 04-01-2020 02:05 AM



The bracket can rest on the lower housing, which makes the failed pivot bracket hard to see; until you use enough tension to break the bracket all the way.

- CaptainKlutz

+1 Ask me how I know.

-- Andy - Seattle USA

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StDane

20 posts in 1571 days


#10 posted 04-01-2020 07:09 PM

Thanks everyone for the replies, but here is the problem. I have done literally everything suggested, except buy new blades. The blade in the saw now is new and clean and sharp. The problem first started with a different, also fairly new and clean blade.

One thing I have noted is that when the top bearings are lowered to just an inch or so it will cut straight, but anything higher than that and it deflects the instant the blade hits the wood. I can’t adjust one side bearing any closer, and it is about 3/32 away from the blade, on the side that the blade deflects to. Again, with a straight-on cut I would not think this would matter. Resawing is one of the big reasons I got a band saw.

Do I need new guides?

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tvrgeek

946 posts in 2386 days


#11 posted 04-01-2020 07:26 PM

Test to see if the guide post stays in line. Maybe some dust got in there and is moving the guide post.
It should be able to cut a straight line with the side guides backed out. Of course, never touching the rear bearing. I follow the advice of moving my blade back. (Snodgrass) Not quite centering the gullets, but further back and it made a world of difference for me.

If this new blade was run and hit a guide, the set will be off and it will not cut a line. I am no pro on a BS, but I made that mistake. Fortunately a $9 Bosch band.

Does the band feel tight? I run my guides about half an inch above my cut. No more.

View Andybb's profile

Andybb

2751 posts in 1340 days


#12 posted 04-01-2020 07:29 PM

As a rule of thumb you should be able to adjust your guides so they are the thickness of a dollar bill away from the blade.

-- Andy - Seattle USA

View bmerrill's profile

bmerrill

97 posts in 810 days


#13 posted 04-01-2020 07:40 PM

Post some pictures of the top and bottom guides.

-- You are not told the truth, you have to learn the truth.

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splintergroup

3667 posts in 1959 days


#14 posted 04-01-2020 07:45 PM

Look closely at your blade teeth. If they ever came in contact with the guide, it could have removed or reduced the tooth set on one side (Also could happen if the blade came off the wheel rubber and made contact with the steel rim).

View Aj2's profile

Aj2

2965 posts in 2534 days


#15 posted 04-01-2020 07:58 PM

I still say it’s the blade.

-- Aj

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