Bandsaw will not cut straight.

[Oldguy48]

My Buffalo horizontal/vertical metal-cutting band saw is probably about 35 years old. It's performed flawlessly for all those years, and required only replacement blades occasionally. Even the drive belt is original! The problem is that it no longer makes a straight cut. Instead of a clean right angle cut, the blade wants to slowly drift about 5 or 10 degrees away from the desired path when the saw is in the horizontal position. I see no play in the guide bearings, or anything else on the machine. Anyone have any advice on this issue? HELP!!

 

[MotoDave]

I have had similar symptoms from a dull blade, try replacing the blade and see what it does? Didn't make any sense to me why it would drift like that, but a new blade solved the issue.

Dave

 

[Oldguy48]

That was my first thought, as well...but changing the blade produced the same result. I've been using blades purchased at my local Lowes. I think they are the Lenox brand. Maybe I should try a different brand of blades???

 

[PT Doc]

Not enough tension?

 

[Strouty]

There are lots of cam bearings that can get worn or out of adjustment. It is hard to say without pictures, but it can take some effort to get it back. Sometimes you can adjust for wear, other times, you need to replace them.

 

[JCByrd24]

Check to see if the saw actually travels in that direction as it is lowered or if there is any slop in the hinge first. If it is tight and the blade just wants to go a different way then the saw travel then my understanding is that it's the blade. My saw cuts very straight normally (I can take 1/64" slivers over 3" angle that measure within a couple thou top and bottom), but just the other day I threw on a cheap hss blade and it wanted to go off to the side right from the start, possibly because the first thing I cut was thin wall. I may not have broken in that blade, which is done by cutting something plenty thick (solid) for the teeth count with lighter than normal down pressure. The teeth on a bandsaw blade are not in a straight line, they're alternating leaning one side and the other. If a manufacturing defect or some mis-use (cutting to thin wall with too course of blade) takes that out you can never get it back.

I've seen different opinions of tension. Some say really tight, some say just a little past keeping it on the wheels. I run mine about as tight as I can get it by hand, but the tension knob isn't huge.

 

[Oldguy48]

Tomorrow, I'll take some pics to post here. I've certainly gotten more than my money's worth out of this machine, and I'll replace it if necessary. But I'm hoping I can adjust it back to normal.

 

[Packard V8]

Tomorrow, I'll take some pics to post here. I've certainly gotten more than my money's worth out of this machine, and I'll replace it if necessary. But I'm hoping I can adjust it back to normal.

If it cut correctly once, then of course it can be made to do so again. It's blade, tension, guides or the hinge wear. Find the problem and repair it. Band saws aren't rocket science, but some are worth more repair effort and expense than others.

jack vines

 

[EdT]

I had a problem like that a long time ago which turned out to be that the lateral guide bearings were set up for a blade just a little thinner than the one I put in and it was causing a bend across the short dimension of the blade. Basically, the blade wanted to cut a circle. Adjusted the blade guides and a new blade and it was all good.

 

[_Dock_]

When band saws won't cut square it's usually not one glaring problem, it's usually several small non obvious problems. Clean everything that has any adjustment, slide or mating surface. Many years of build up can cause the pulleys to have camber and it will not be obvious to see. Is the blade popping off also?

 

[Halfdawg]

Bi metal blade? On my little 4x6 saw the $10 regular saw won't cut worth a ****, put a $30 bi metal blade on and it cuts awesome until I screw it up.

 

[catalytic]

Not to belabor the obvious, but does your saw have a tracking knob that can be adjusted? I use mine to adjust blade drift until the blade cuts square with the table.

 

[Oldguy48]

I think I may have found the problem. Laying a square on the base, there is at least 1/8" difference between having the blade raised up about 6" and it's resting position at the bottom of its travel. It looks like possibly the pivot pin is worn. I guess I have a repair project to get it straightened out. Thanks for all the replies.

 

[Gizmosity]

On some saws the "pivot pin" is eccentric and rotating it allows one to keep the blade vertical throughout its travel arc.

 

[Oldguy48]

On some saws the "pivot pin" is eccentric and rotating it allows one to keep the blade vertical throughout its travel arc.

Good to know that...I had no idea. I'll check that out before I disassemble anything.

Wayne

 

[Gizmosity]

I found this video helpful:

It's for a model B Kysor Johnson. I have a model J but the adjustments are the same. Not so sure on yours, but it's worth a shot.

 

[Oldguy48]

I found this video helpful:

It's for a model B Kysor Johnson. I have a model J but the adjustments are the same. Not so sure on yours, but it's worth a shot.

Excellent informative video. Thank you for posting that. I'm confident that with all the suggestions & tips & video, I can get this saw to perform as intended. Thank you all for the assistance.

Wayne

 

[gus1962]

I have experienced this kind of problem, if it's not the band saw blade, it's the tension or guides. Good thing everything is back to normal.
You mentioned that your bandsaw is 35 yrs old, what do you apply to prevent it from rusting? Do you do wet cutting?

 

[Oldguy48]

I have experienced this kind of problem, if it's not the band saw blade, it's the tension or guides. Good thing everything is back to normal.
You mentioned that your bandsaw is 35 yrs old, what do you apply to prevent it from rusting? Do you do wet cutting?

I've not had a problem with rusting. I just brush the chips off as needed. Most of my cuts are dry, although occasionally I have used "Cool Tool" or "Spray Tap".

Wayne