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David McCollum
06-04-2008, 07:13 PM
I am having trouble with my bandsaw cutting straight. I am ripping white oak, something I have lots of experience with, but I have never had this much trouble. The blade seriously veers off, bending the blade and jamming the piece against the fence, and will stall it if I keep feeding.

At first I thought I had a dull blade, but a new blade does the same thing. These blades are a quarter inch wide, with 4 teeth per inch, supposedly okay for ripping, according to the package they came in.

Any advice would be appreciated. Thanks.

Captain Blight
06-04-2008, 07:19 PM
If your tension is correct, guides etc. set correctly, check your tires. They may be collecting sawdust or may need a recrowning.

Dan McCosh
06-04-2008, 07:21 PM
I've had this problem when the blade isn't centered on the wheels, which sets it off on an angle.

Rob Hazard
06-04-2008, 07:45 PM
How thick is this oak you're ripping?

For any serious ripping, my saw is usually happier with a 1/2" blade.

pipefitter
06-04-2008, 07:52 PM
I usually suspect the blades when they come in a package. Typically blades from the big box stores come in blister packs and aren't worth the package they come in, name brand or not and they are usually very thin metal. I use Lenox blades, even though they may not be top of the line, they sure are durable for the $. I've had the same 6tpi x 1/4" blade in my saw since October cutting aluminum every day with it.

Some cheaper saws have a natural path they will want to run that is not always square with the table and you may have to adjust your rip fence to compensate. To get close, you can take a 12" scrap piece and put a parallel pencil line along the rip edge, feed it about half way through and notice how the piece is sitting in relation to the table. This will get you close to the angle the fence needs to be. Once you get it set to make a uniform rip, read the angle of your fence with a bevel finder and keep it for reference so that you may set your fence up accordingly for different size rips. I usually transfer this angle mark on something permanent so that I may pick it up again in the event I need the angle gage for something else. This is only if the saw can't be perfectly tuned or if you don't have the means to tune it.

Best to get a book that shows how to tune the saw. To explain it here would take awhile.

merlinron
06-04-2008, 08:13 PM
several reasons this could be happening .
if you are sure your guide alignment is good... blade isn't being pushed out of a straight path from upper to lower wheel.... i would suspect you've either lost set on one side of the blade or for some reason dulled one side. either one of these will make it wander no matter how well aligned things are, especially when resawing..

David McCollum
06-04-2008, 09:12 PM
Thanks for the advice. The saw is a 20 year old Craftsman, and I have always used Craftsman blades. The wood is 5/4 thickness. You have given me lots to look into.

Cuyahoga Chuck
06-04-2008, 09:19 PM
There are bandsaws and there are bandsaws.
Bandsaws cut straightest when there is a lot of tension on the blade. If you have a bandsaw with a cast iron frame you have what it takes to pull the blade tight. If you have a lesser machine, like most of us have, the back bone of the frame will give and tension will be limited.
Bandsaws need regular tune-ups. Clean the dust out, make sure the tires are OK, adjust the guides or blocks to keep the blade straight.
If you are going to rip you need the widest blade the saw will take. Wider blades can, of course support more tension. What you are using is intended for cutting curves.
A blade, no matter how well set up will flex to the side if you push on it hard enough. You have to let the blade do the work.

Gary E
06-04-2008, 09:32 PM
Ok.. so I got this from Norm on the THIS OLD HOUSE show

Your 1/4 in blade... arnt they for countour sawing? not resawing??

He sets up at least a 1/2 in blade, bigger if your machine will handle it...
crank in plenty of tension and make sure the guides are set correctly.

The fence.. your most likely using a solid fence on the table, set to what you think is parallel to the cut...it's not..
Norm's guide is what amounts to a PIN, aprox 3/4 in dia mounted the proper distance from the blade so he can follow the pencil mark on the material being cut.

Maybe their website will show and explain what I forgot.

pila
06-04-2008, 09:44 PM
Like mentioned above, the blade guides are the key to make the blade stay straight. Your saw should have a guide both above and below the table, and a ball-bearing behind it to support the back side of the blade when you lean into a cut. The guide set-up is crucial, as well as blade tension. The guide assembly has to be re-set each time you use a different width blade, and the side guides need to be just behind the teeth to hold the blade so it can run true. Look your saw over and make sure you understand how the adjustments work, and you may discover how to make it work like you need it to.:)

kc8pql
06-04-2008, 10:02 PM
.... i would suspect you've either lost set on one side of the blade or for some reason dulled one side. either one of these will make it wander no matter how well aligned things are, especially when resawing..

If everything else is OK I'd suspect this too. It's not unusual for inexpensive, and sometimes even premium blades to have an uneven set. Many bandsaws have fences that have angular adjustment. One way to compensate is to cut freehand to a straight line drawn on a piece of scrap the length of the fence. Stop the cut half way through. Without moving the cut piece, draw a line on the saw table and align the fence with the line. It may take a little fiddling, but you should be able to get a straight cut against the fence when the alignment is right. 5/4 isn't that thick. Most any bandsaw should be able to rip that.

john welsford
06-05-2008, 03:34 AM
Out of interest, does it always veer the same way? If so its likely that the blade is blunt on one side ( hit something sometime) .
I do agree though that a wider blade will help, and I dont buy blades prepackaged ( where do you think Craftsman get them? ) I go to a local saw filing and tool sharpening shop with the old blade and ask for a new one . Their commercial customers wont tolerate product that does not perform so they generally supply good stuff.
Mine goes best on 3 tpi and 3/4 in wide blade, and I can rip 250mm thick Kwila hardwood with that ( and some patience)

John Welsford


I am having trouble with my bandsaw cutting straight. I am ripping white oak, something I have lots of experience with, but I have never had this much trouble. The blade seriously veers off, bending the blade and jamming the piece against the fence, and will stall it if I keep feeding.

At first I thought I had a dull blade, but a new blade does the same thing. These blades are a quarter inch wide, with 4 teeth per inch, supposedly okay for ripping, according to the package they came in.

Any advice would be appreciated. Thanks.

SeaLeveler
06-05-2008, 04:23 AM
As mentioned above,run board of oak with parallel line down center halfway through saw and stop cutting and cut off saw while holding board still.Mark line on table along edge of board.If your Craftsman is like mine,the fence is not adjustable so I loosen the bolts between the trungion guide and saw frame while leaving the angle setting bolt tight at 90 degrees.Line up mark on table parallel to blade then add spacers between the trungion and saw frame on one vertical side only to line up table.I use thin washers and cutouts from a drink can.Tighten bolts then repeat cut and adjust with more or less spacers as needed to acheive straight cut with fence.

Mrleft8
06-05-2008, 08:52 AM
OK....First get rid of the Craftsman blades. Get GOOD quality blades from an on-line source like Suffolk machinery ( WWW.Timberwolf1.com )
Second....1/4" blades are for cutting curves, not straight. Get a 1/2" blade minimum.
Third... Make sure that your wheels are in plane with eachother, and that the blade is tracking in the center if the tires are crowned, or at the front edge if they are flat.
Fourth.... Make sure that your blade guides are set properly. If you have "blocks" the blocks should be set only about the thickness of a piece of tissue paper away from the sides of the blade. The rear thrust bearing should not spin until you feed a piece of wood into the blade, but should spin the second that you feed a piece of wood into the blade. (both top and bottom....The bottom guides are often neglected.)
Fifth... If you saw has been abused or neglected for an extended period of time it may need serious repair. If you still want ti resaw your Oak before this happens you can set your fence to accomodate the "drift"...... This is a fairly unsatisfactory solution that will deliver barely adequate results, and only continue to abuse your saw.

InTheBeech
06-05-2008, 09:37 AM
I would suspect the fence. This makes all the difference with my Laguna. Run a piece of wood part way in to the blade, stop the machine without moving anything and look at the clearance left by the kerf at the back of the blade's width. It needs to be even on both sides. If not adjust your fence accordingly. Shim, file holes - do whatever you need to do to make sure the fence is parallel with the blade using this technique. Of course your tension, blade guides, tires, and squareness of the table to the blade should also be tuned properly. But I think that the fence is off and you will see improvement.
Ed
Good luck.

kc8pql
06-05-2008, 11:08 AM
I am ripping white oak, something I have lots of experience with, but I have never had this much trouble. The wood is 5/4 thickness.


If you still want ti resaw your Oak before this happens you can set your fence to accomodate the "drift"...... This is a fairly unsatisfactory solution that will deliver barely adequate results, and only continue to abuse your saw.


He's not trying to resaw. He just wants to rip 5/4, which apparently he's done before with this same saw.

Bob Cleek
06-05-2008, 11:46 AM
Most all of what has been said above is absolutely correct if you are considering resawing. However, it seems to me a bandsaw is the wrong tool for the job in the first place. For ripping inch and a half oak, I'd use a table saw. Generally speaking, table saws are for straight cuts and bandsaws are all about curves. (I know, there are those who cut curved planks on a table saw and there are bandsaw applications, like resawing, that require straight cuts, but we're talking generalities here.)

Tom Robb
06-05-2008, 05:20 PM
Advice I got from Carter (the bandsaw mavens) is pretty much all of the above - good skip tooth blade, properly set guides, enough tension (may need aftermarket tension spring) non scrap tires, don't push it, and the blade set on the tires with the tracking screw such that the edge of the gullets of the blade is in the center of the tire. If it isn't centered the blade will curve one way or the other.

John Meachen
06-05-2008, 05:54 PM
Unless you have several hundred feet to saw,just mark the line and saw to it freehand.

merlinron
06-05-2008, 06:31 PM
there was a thread on here a while back,... quite a while... where it was decided that a band saw may be a more universal saw in comparison to a tablesaw for the purposes of boatbuilding. those who say the band saw is not the right tool for this guy to rip lumber with, might want to re-think.
i personally, don't agree with the above, i'm just bringing to point a consensual(word?) fact.

David McCollum
06-06-2008, 01:58 PM
Thanks for all the advice. The reason I prefer the bandsaw for this operation is I am cutting multiple slats of approximately 1/8 inch thickness for laminating. I like the rough surface the bandsaw leaves behind because it should help strengthen the glue joint. Of course, the real reason why I do not use a table saw for this is I do not own one. But after reading everyone's suggestions I started over with the blade installation instructions. While I was carefully following the instructions, I noticed that the tracking adjustment did not seem to work right. I would make an adjustment to get the blade centered on the wheel, give it a spin, but it would not stay in one place. I suspect it wanders because the bearing on the wheel may be worn. If that is the case then blade guide resetting is going to be a moving target. I have yet to try the fence alignment suggestions. I'll do that tonight. I appreciate all the help.

Tom Robb
06-06-2008, 03:47 PM
If the saw is worn enough to need repair, I guess that getting it to do your job will be endless frustration until you either fix it or replace it with a better one. I had a pretty old Sears bandsaw once that I got cheap. It was better than no saw, but not by much.