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View Karda's profile

band saw won't cut straight

by Karda
posted 12-18-2019 04:35 AM


21 replies so far

View Hockey's profile

Hockey

182 posts in 1327 days


#1 posted 12-18-2019 05:09 AM

Could be a number of things. Blade guides not properly adjusted, blade tension, dull blade, blade width and feed rate are the usual culprits.

View RobS888's profile

RobS888

2829 posts in 2760 days


#2 posted 12-18-2019 05:12 AM

Have you watched the Alex Snodgrass video? It helped me. Especially about centering the gullets on the crown of the top wheel, not the blade itself.

-- I always knew gun nuts where afraid of something, just never thought popcorn was on the list.

View TDSpade's profile

TDSpade

121 posts in 3331 days


#3 posted 12-18-2019 07:03 AM

What size blade? The thinner the blade the less accurate the cut. What type of blade, regular, hook, or skip? What tpi (teeth per inch) are you using? Is the blade old and dull? Hard or soft wood?

Cross cutting is easier than ripping. A ¼ inch blade will tend to follow the grain easier and give a less accurate cut than a ¾ inch blade when rip cutting.

Just some thoughts.

-- For every expert, there is an equal and opposite expert.

View Karda's profile

Karda

2602 posts in 1468 days


#4 posted 12-18-2019 07:09 AM

blade is .5” 3 hook tooth. Blade is used but not real hard. This has never happened before. does it in hard and soft wood. I free cut a piece of OSB. and the blade cut straight then

View HokieKen's profile

HokieKen

15319 posts in 2053 days


#5 posted 12-18-2019 12:51 PM

Free cuts will always be straight… well as straight as the operator can push it anyway :-) It sounds like you have a tracking issue. Maybe the blade changed position on the wheels for some reason? You don’t say how your sled is made but, if it rides in the miter slot, you probably need to adjust your table or if it rides on the fence you probably need to adjust that. Good luck with it. Bandsaws are great when they cooperate but they can be frustrating buggers too…

-- Kenny, SW VA, Go Hokies!!!

View Robert's profile

Robert

4148 posts in 2395 days


#6 posted 12-18-2019 02:41 PM

Dull blade? Forcing too much can also do it.

Check the guides and blade for sharpness.

I’ve tried the Snodgrass deal go ahead if you want but it doesn’t work on every bandsaw.

-- Everything is a prototype thats why its one of a kind!!

View GrantA's profile

GrantA

2921 posts in 2322 days


#7 posted 12-18-2019 02:44 PM

All bandsaws have drift, just the nature of the beast. The fence and /or sled have to be able to compensate for it, and our must be checked after switching blades too.

View Aj2's profile

Aj2

3498 posts in 2713 days


#8 posted 12-18-2019 02:49 PM

To me it reads like a dull blade. It doesn’t take much to smoke a carbon steel blade OSB has nasty glue. One of the reasons to have a larger then needed bandsaw is a longer blade. Longer blades might cost you more up front but they pay off in the long run.

Good Luck

-- Aj

View Phil32's profile

Phil32

1181 posts in 818 days


#9 posted 12-18-2019 04:43 PM

Possibly the tooth set of the blade. Alternate teeth are set (bent) to the side to make the kerf – the clearance of the blade in the saw cut. This can happen with incorrectly adjusted guides or normal wear. Try a new blade.

-- Phil Allin - There are mountain climbers and people who talk about climbing mountains. The climbers have "selfies" at the summit!

View Karda's profile

Karda

2602 posts in 1468 days


#10 posted 12-18-2019 08:27 PM

ok thanks I’ll get a new blade

View JayT's profile

JayT

6414 posts in 3126 days


#11 posted 12-19-2019 03:24 AM

The only times I have drift on my band saw is dull blade &/or too fast of feed rate. The thicker the wood, the slower you need to cut to give the blade a chance to clear the sawdust. Forcing a piece through too fast will leave too much sawdust in the kerf, which pushes the blade to one side.

-- https://www.jtplaneworks.com - In theory, there is no difference between theory and practice. In practice, there is.

View Karda's profile

Karda

2602 posts in 1468 days


#12 posted 12-19-2019 03:44 AM

this piece was abou 3×3’’ hardwood and my feed was very slow, probably is dull

View GrantA's profile

GrantA

2921 posts in 2322 days


#13 posted 12-19-2019 01:09 PM

Mike you didn’t say (or I missed it) whether you’re sled rides on the fence or in the miter slot or whether it’s adjustable
You might get lucky and think there’s no drift like Jay but the bottom line is you’ve got a thin piece of metal stretched out 2ft or better between 2 wheels that do not have any adjustments besides tracking on a mass produced machine.
I’d bet a cold beer if you set the fence dead on with the miter gauge slot you will not get a drift-free cut

View Karda's profile

Karda

2602 posts in 1468 days


#14 posted 12-19-2019 06:05 PM

the sled runs on the miter slot but the fence is squared with the blade, the last time I cut to a line it was dead on then next cut it is way off

View TDSpade's profile

TDSpade

121 posts in 3331 days


#15 posted 12-19-2019 06:49 PM



the sled runs on the miter slot but the fence is squared with the blade, the last time I cut to a line it was dead on then next cut it is way off

- Karda

Sounds like a tracking problem. How old is your bs? The tires could be worn, causing the blade to move around. Is the blade tension properly set? Don’t trust the markings when adjusting the tension. The tension spring could be weak.

I had worn tires, which would cause the blade to move off the crown, screwing up the tracking. Changing the tires fixed that. Difference was night and day. Like a new bs.

-- For every expert, there is an equal and opposite expert.

View Karda's profile

Karda

2602 posts in 1468 days


#16 posted 12-19-2019 07:18 PM

My saw is about 2 yrs old this Is not a tool I use on a daily basis but at times i use it alot, mostly for bowl/turning blanks. It shouldn’t be wore out yet but is not a high end saw. I am never getting a 1/2 inch blade again for some reason i get get 1/2 inch to adjust right and that is what came on the saw

View Lazyman's profile

Lazyman

5947 posts in 2302 days


#17 posted 12-19-2019 11:05 PM

After 2 years it is probably just dull but sawing green wood for bowl blanks can cause build up that will have a similar effect as a dull blade. You might try cleaning it if there is a bunch of gunk of the blade. I use Simple Green cleaner and soak the blade while coiled in the largest cheap clear plant tray I can find at Home Depot. After about 10 minutes I uncoil and wipe the blade off or use an abrasive pad for stubborn areas. I usually put a little wax on the blade afterwards. You can just use a candle for that. I also occasionally rewax the blade while it is running to help prevent buildup.

-- Nathan, TX -- Hire the lazy man. He may not do as much work but that's because he will find a better way.

View Karda's profile

Karda

2602 posts in 1468 days


#18 posted 12-19-2019 11:58 PM

there is no buildup on the blade that has been worn off. I cut a piece today and used a line the I cut on the line and it was hardly any drift,maybe a 32nd at the end of the cut, when I cut very slow I can see individual teeth cut, its a 3 tooth blade. being a 1/2 inch blade I can’t get it on the wheel where it belongs

View Karda's profile

Karda

2602 posts in 1468 days


#19 posted 12-20-2019 07:20 PM

I cut a 1 x on a line and the saw was accurate. I later cut off a piece from a box blank about 2.5” in diameter and the cut was way off. Apparently the problem is only when I cut thick wood

View Lazyman's profile

Lazyman

5947 posts in 2302 days


#20 posted 12-20-2019 10:23 PM

That’s pretty common with a dull blade. You could try to sharpen it. Matthias Wandel has a video on how he does it with a Dremel just on the top of the tooth. This video shows just how much difference it can make, even with a new blade (he uses his bench grinder). I’ve never tried this but it seems like it could save you a few bucks or perhaps get you back in business until you get a new one.

BTW, the rule of thumb is that you should have at least 3 teeth in the cut at all times so a 3 TPI blade is not the best choice for boards that are thinner than 1”.

-- Nathan, TX -- Hire the lazy man. He may not do as much work but that's because he will find a better way.

View Karda's profile

Karda

2602 posts in 1468 days


#21 posted 12-20-2019 10:58 PM

I change the blade or resharpen thanks

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