BANDSAW DRIFT---HELP!

It’s either tension or feeding too fast I would think.

The curve means that the blade is flexing.

Set the tension higher.

Try drawing a line down the center of a board and cut it following the line.

-- Gary, East TX -- The longest journey begins with a single step.

Looks like your tension is WAY too low and one must tension properly before trying to set the fence for drift. You might try getting info on the tension for the woodslicer you are using. I use carbide blades for the band saw and they use different tensions. It could be you have too many teeth on that particular blade. For re-sawing, I recommend a 1.5 to 2 teeth per inch blade. You must have enough space adn gullet depth for the material to pass through the wood. The more teeth the more heat build up. John

-- Oldworld, Fair Oaks, Ca

I had similar trouble until I saw a magazine article on how to make a resaw jig. Finished it yesterday and I cut a piece of 3mm veneer 10” wide as straight as you can get. If you would like a copy of the article send me a message. glad to do the same for any other jocks.

-- Grumpy - "Always look on the bright side of life"- Monty Python

I have been having the same problem. I got tons of great advice on my blog about my bandsaw frustrations. (Check it out).

If your blade is too wide you may not be able to tension it properly. Against your better judgment, a narrower blade may work better because you can achieve greater tension.

-- Dust collectors suck.

When I finally pulled my 1” resaw blade and put on a new wood slicer the problem I was having disappeared.
It only takes one or two teeth to spoil your cut and.. your tension is too low regardless.
Try a new blade before you waste any more time.

Bob

-- A mind, like a home, is furnished by its owner

Tension is the curve problem. Make sure your blade is running in the center of the tire. Adjusting that will effect your drift. If you can get the blade right in the center of the tire/wheel you will barely have any drift.

-- Tim -- http://tmuli.com

If you’re guide rollers are pressing against the teeth instead of the body of the blade, that can cause the cuts you see here. Low tension is probably to blame as well.

Thanks everyone!! Blake, GREAT POST. That really has some good info.

I thought y’all would find it interesting that my B-saw HAS NO TENSION SPRING. It is an old Brodhead Garrett J-Line 20” bandsaw that I picked up from a high school woodshop. I practically dissected the thing before I tried to run it, and I was shocked to see that there is no spring in the wheel tensioning system. There’s just a big threaded rod with a wheel handle that threads into the upper trunnion (I think that’s the right term). You can see it below the upper wheel door in the photos.

Here is a picture of the MODEL of bandsaw saw I have—-THIS IS NOT MY SAW!! Mine actually has a table and runs…sort of.

Would anyone advise trying to add a compression spring to the saw’s tension system, or should I just leave it alone and try to find the correct tension anyway?

I’m worried that all the strain is on the blade, and if the blade encounters any extreme tension during a cut, there is nothing to absorb the strain, therefore….SNAP!…buh-bye to a $50 blade. There’s a big ol’ 3HP motor on the saw that runs 3450 RPM and transfers 690 RPM to the drive wheel via a 2” pulley and a 10” pulley. THE RESULTING TORQUE IS MASSIVE….. to say the least.

So I’m confident that my motor can cut anything I put in the saw, but will my blade do so under occasional extremes/shocks of high tension?

-- Lane Custom Guitars and Basses

Another, thought:

Sometimes, a dull blade will yield strange results; however, they tend to be less severe than what you show. Either way, a sharp blade, plus proper tension, will help to get you in the confort resawing zone.

If you have a little time, read some of the stuff I have written on my blog – you might already be familiar with most, or all of it.

-- Al Navas, St Joseph, MO, http://sandal-woodsblog.com

If you’re serious about setting the tension in your bandsaw blade properly, then you should invest in a bandsaw blade tension gauge.

Otherwise, it’s just a guess (though it may be an educated and fairly accurate one in many instances…).

-- Ethan, http://www.merganserwoodworks.com, http://greystonegreen.blogspot.com/

One way that helps is to score the cuts. I always use a marking guage to score the cutline on each side of the board. Another way is to use a tablesaw blade to take a very shallow cut on each side so that the even thinner bandsaw blade will follow. This isn’t so great for thin veneers as most TS blades don’t get much thinner than 1/8”.

Tension is my guess as well as far as your direct question. The blade is flexing. Can’t think of another way that a curved cut is possible. I’d slow down as well to eliminate that variable. Blade choice could be a culprit. As much as I hate changing blades, it is an absolute must when going from curved cuts to resawing or something of the like.

-- Jeff, South Carolina

THANKS EVERYONE. I TRIED YOUR SUGGESTIONS FOR TENSION AND CHANGED THAT 1/4” OF BLADE FLEX INTO ABOUT 1/16”. But it still flexes a little to the left, with the tension as high as I can set it. Maybe I need to angle my fence more to the right. Today I was cutting through 4” of qtr-sawn red oak and I couldn’t get a flat surface. The resultant boards were thinner in the middle along the length, and the blade still flexes in the cut. HELP!!! THIS SAW WILL BE USED EXCLUSIVELY FOR RESAWING.

So I’m probably going to start a big argument, but what would be everyone’s recommendation for brand of resaw blade? I’m not really in the market for carbide (unless you know of a place that sell them for less than 50 cents per inch—I need 12’ 4” or 148”) but I would like to know what works for different people. I am drawn to the Woodslicer because of the variable tooth spacing. It really makes a smooth cut surface that requires little more than sanding. But maybe it’s not the right blade for me.

Should I go with a 1/2” blade instead of 3/4”? Should I change to urethane tires? Where can I get shims to get my wheels to be coplanar? How do I get my top wheel to stop wobbling? (yes, I can spin the wheel by hand and watch the blade track from front to back of the tire as it turns). My saw is obviously not in as good of shape as I had thought or hoped….it is over 40 years old and was used by high school students ….yikes!!

Thanks for the great suggestions…KEEP ‘EM COMING

-- Lane Custom Guitars and Basses

The only quality blades I’ve used are Timberwolf’s. Woodslicer’s reputation is enough for me to consider them in the upper echelon as well, but I haven’t used it myself. Number of TPI and the hook set are also key. Any manufacturer will have information in determining the pro’s and con’s of all their variables.

The wheel wobble is without a doubt and issue if you can visibly see a wobble. All saws are a little different in tuning this. I’d search the net for a model specific manual or forum. Changing tires never hurts, but might not be the culprit. Urethane is the way to go, I’m told. I would not go down to 1/2” from 3/4” unless the saw can’t handle 3/4”. The larger the better is a true statement until the point where the motor can’t handle the size.

-- Jeff, South Carolina

Do you have the blade(s) tracking in the MIDDLE of the tires?

-- Have Fun! Joe Lyddon - Home: http://www.WoodworkStuff.net ... My Small Gallery: http://www.ncwoodworker.net/pp/showgallery.php?cat=500&ppuser=1389"

Is it at all possible that he (you) may be trying to run it thru to quickly?Your pictures show what looks like burning to me. A piece of clear packing tape on one side of the cut edge helps to prevent that even in band saws.If I just made a complete fool out of myself with this thought let me know I can handle it!
LOL!!! PEACE!!!

-- Allison, Northeastern Ca. Remember, Amateurs built the Ark, Professionals built the Titanic!

Joe, the upper tire has a noticeable wobble, as if the bearings are not pressed into it straight. I have the blade tracked in the middle as best I can, but it moves slightly forward and back on the tire because of the wheel wobble. I may have to replace or re-press the bearings.

Thanks Allison!! Great to meet you. If you could post a picture of what you mean by ”A piece of clear packing tape on one side of the cut edge helps to prevent that [burning] even in band saws,” that would be great. My brain isn’t visualizing your suggestion—my fault. Thanks!!

Anyone else have help to offer? Thanks.
Alex

-- Lane Custom Guitars and Basses

I had the same problem with my 14” bandsaw. When I tried to use a 3/4” blade(the max blade size for my saw) the cut would drift towards the fence on the bottom side of the piece on anything taller than about 3”. You couldn’t even tell anything was wrong until the saw started to bog down. I tried to increase the tension, but that did not work. I eventually maxed out the tension and then the belts started to slip instead of turning the wheels.

Based on advice from others I ordered a 1/2” wood slicer blade. The difference is night and day. I adjust the tension to the 3/4” blade mark on the tension scale and get nice clean, straight cuts. I have resawed 9” tall white oak that was 7 feet long. A couple of light passes through the planer cleaned up the slight variation in thickness, caused by me, not the saw.

-- Mark

For shims or other parts I’d try Iturra Design in Florida. They have no website so you’ll have to call them. A search on “Iturra” here on lumberjocks should get you their phone number. You might even be able to get help from them on what to do with your saw to cut straight. They specialize in band saws and are really really good. Their catalog is a great reference on band saw tuning itself. If Iturra can’t help you I’d try Mark Duginske’s Band Saw Handbook .

In some of your posts, Joe, it’s unclear to me whether you’re talking about drift, or a straight cut vertically, as the wood goes through the saw. Drift, as long as it stays consistent once you’ve set your blade tension, isn’t a problem.

BTW, I have a 3/4” alternate-toothed woodslicer on my 14” in saw and love it.

-- johnjoiner

Alan,

Sounds like your machine is in DIRE need of more work (repairs).

IMHO, your machine is very dangerous to use at all!

Get your wheels Coplanar, bearings replaced (or whatever), etc. to get them so they can spin without ANY WOBBLE AT ALL… and also very quietly!

You might also replace the tires because they’re probably shot.

Get all that done… THEN proceed to try again… tuning it up, etc. then trying again.

If you don’t know how to tune up the saw, check out some books by some of the pros, like David Marks, & others… from Taunton press.

Good Luck!

If you continue to use that saw now, IMHO, you will be taking a great risk of injury.

-- Have Fun! Joe Lyddon - Home: http://www.WoodworkStuff.net ... My Small Gallery: http://www.ncwoodworker.net/pp/showgallery.php?cat=500&ppuser=1389"

Contact this company (no web page) and get their catalog. The catalog is said to be a instructional bible on the saw.

http://www.manta.com/coms2/dnbcompany_l6b7r

You have to call him for the catalog and keep trying. It’s busy quite a bit.

Search the company name on google (Iturra Design) and you will see the number of positive reviews on his merchandise to tune your saw.

-- There is no such thing as scrap wood!, http://www.saltrivergallery.com