Band Saw Fence and Drift

[fritz eng]

Is band saw drift a factor when using a fence? Obviously the use of a fence is primarily for parallel cuts and re-sawing.

[Rob Luter]

I've seen it suggested that drift is really misalignment between your fence and blade. I spent a ton of time aligning my band saw table and fence when I got my saw. I don't have much of an issue with drift.

[Doug Garson]

Yes, if your blade has drift and your fence is not set at the drift angle then the cut will try to follow the drift angle and push the workpiece towards or away from the fence. If the workpiece stays in contact with the fence, the blade may deflect (depending on how close your guides are) or just bind in the cut.

[Thomas McCurnin]

I think the absolute best way to avoid drift with a fence is to tune up your band saw, although you can measure the drift and create an angle compensator, which is old school. The best method I have seen is on a video called tuning up your band saw for the anally retentive. https://www.youtube.com/watch?v=9DzbJYIPPNE (https://www.youtube.com/watch?v=9DzbJYIPPNE)

[fritz eng]

A follow-up question: do blades of different widths drift differently? Additionally, once the drift of a blade is determined and the table adjusted accordingly, will that be the "permanent" position of the table for all blades? In other words will the table set up be a one time event? Thanks

[Zachary Hoyt]

A sharp blade on a well set up bandsaw will not drift if the feed rate is kept reasonable. Each blade will be dull in its own way, so if the blade is the problem then when you change blades the drift will change. If you switch blade widths or types then I would also expect the drift to change and require readjustment. I have not learned to sharpen blades yet, so for me when a blade begins to drift it is time for a new one, which has always taken care of the problem so far.

[Doug Garson]

My understanding is there are two potential causes for drift, either the saw setup, meaning the blade is not parallel to the miter slot, or the blade. If you cut curves with the blade, one side of the blade may dull more than the other causing drift or the blade itself as manufactured may not have equal set or sharpness on both sides. So you can start with a well set up saw with no drift and after cutting a bunch of curves or changing blades start getting drift. Best to check for drift before you make any critical rips or resaws if you have been cutting curves or change blades.
Sharpening blades is not difficult assuming not carbide blades or high tpi blades. I just tried it for the first time a few days ago and took about 10 minutes to sharpen a 105" 3 tpi blade. Lot's of videos out there showing how, I did it on the saw(unplugged) and just touched the tip with the side of a cut off blade in my Dremel. Dramatically improved the cut, haven't checked if it affected the drift yet, will do that if I need to rip or resaw with the fence.

[Rod Sheridan]

A follow-up question: do blades of different widths drift differently? Additionally, once the drift of a blade is determined and the table adjusted accordingly, will that be the "permanent" position of the table for all blades? In other words will the table set up be a one time event? Thanks

Yes.....Regards, Rod

[Derek Cohen]

Drift can also occur when the wood is reactive, opens up when sawn, and one side pushes away from the fence.

Regards from Perth

Derek

[Robert Hazelwood]

Drift can also occur when the wood is reactive, opens up when sawn, and one side pushes away from the fence.

Regards from Perth

Derek

Yes, I suspect a lot of reported drift is actually cause by this. It is not always obvious what is happening and what you notice is the blade drifting towards the edge/face you had against the fence.

Otherwise I think it is an issue with blade set or sharpness. This is what would cause a handsaw to go off a line.

I see how the setting of the wheels and tracking can affect the angle of the blade, but the blade should still cut straight at whatever angle it happens to be. So it is just a a matter of adjusting the wheels until the blade is parallel to the miter slot and fence, or adjusting the table to suit the blade.

I can't see any reason why a blade would cut at say 5 degrees off from the angle of the band, without there being something wrong with the blade.

The other issue might be the band flexing under the feed force. I can see this causing the blade to want to twist and wander. This may be why drift seems to be a less reported problem on larger heavier saws running bigger bands at higher tension. The greater beam strength minimizes blade flex.

[Darcy Warner]

The other issue might be the band flexing under the feed force. I can see this causing the blade to want to twist and wander. This may be why drift seems to be a less reported problem on larger heavier saws running bigger bands at higher tension. The greater beam strength minimizes blade flex.

As a connoisseur of large bandsaws, there is a difference in performance with different tensioning mechanisms, wheel styles, weight, etc.

Knife edge style tensioning makes a noticable difference in smoothness. Solid disc or Carter/tannewitz wheels are much improved vs. cast spoked wheels, never had a BS with a miter slot.

If I need to resaw on my BS, i have a single point fence i use.

I prefer to resaw with a resaw.

Blades will drift, it's mostly due to tooth set when new and tooth wear when used.

[Christopher Charles]

The fence on my saw is straightforward to adjust for changing drift, which I usually check when switching blades using a ~24" piece of scrap. Mark a line parallel to the fence side of the scrap, carefully freehand cut the scrap about 1/2 through, hold in place to the table. Nearly always it will be non-parallel to the table by a degree or two. Adjust the fence parallel to the scrap and that's it.

[Josko Catipovic]

I remember once setting up my bandsaw for drift, and then rounding the back of the blade with a stone. I happened to just touch the stone to the teeth on one side (oops!) and on the next cut, drift angle was way different. That involuntarily confirmed that teeth set is an important part of drift. (I am NOT suggesting that one adjust drift by stoning one side of the teeth.)

[Robert Engel]

Ok, this always gets me going.......:-D

First of all, its a fallacy to think drift means there is something wrong. Common sense tells me it that were true, bandsaw fences wouldn't be made to adjust and the manual for every single bandsaw I've ever owned (4 to date) talk about adjusting the fence for drift.

You can do the tricks everybody talks about to eliminate it, then find out for yourself it works or doesn't work. It certainly doesn't work on either one of my bandsaws.

I like Michael Fortune's technique of setting fence parallel to slot and adjusting table.

That said, how hard is it to simply align fence to drift?

I know I'm checking that every time I resaw regardless of how well tuned my saw is.

[fritz eng]

I'm beginning to think that regardless of drift, one will do their best to have the material tight up against the fence to get the desired cut and let the "chips fall where they may"...............

[Derek Cohen]

I'm beginning to think that regardless of drift, one will do their best to have the material tight up against the fence to get the desired cut and let the "chips fall where they may"...............

Actually Fritz, that may be the root of the problem if you are dealing with reactive wood (see my earlier post).

This is the reason I use a shortened fence. It permits the board to open up away from the fence, and do so without creating drift.

https://i.postimg.cc/ry75CHFY/IMG-2801.jpg

Regards from Perth

Derek

[ChrisA Edwards]

I had to resaw quite a lot of long boards with minimal waste allowance, so when I started getting drift I went in search of a reason and a solution.

First, I went with a carbine tipped 3/4" blade (ReSaw King), the largest my bandsaw could use. That didn't cure it.

After watching several videos, I was back to adjusting the tilt angle of my upper wheel to get the blade to run in perfect alignment to remove drift. I also bought a Carter Magnetic fence and F.A.S.T (Fence AlignmentSystem Tool).

I used the Carter tools (https://www.carterproducts.com/band-saw-products/band-saw-magfence) to identify the drift angle easily and to allow me to reasaw with the Carter fence instead of my bandsaw fence without drift affecting my work piece.

After successfully resawing all my long boards, I used the Carter fence to help me micro adjust the bandsaw tilt wheel to get the blade tracking perfectly parallel to the miter slot. This then allowed me to adjust my bandsaw fence.

Now I don't have any drift and can use either fence option.

[John TenEyck]

This is a never ending story it seems. What people would not think of tolerating with their tablesaw has become accepted practice for their bandsaw. A sharp blade with teeth having equal set will cut straight if it has enough tension and is properly adjusted on the wheels. What's that mean? Put the blade on the center of the upper wheel (for crowned wheels), adjust the miter slot parallel with the blade and the fence parallel with the miter slot. Done. If your saw won't cut straight after that then check the wheels to see if they are coplaner.

Adjusting the fence for drift is something you do as a short term solution for a dull blade that no longer cuts parallel with the miter slot.

John

[Doug Garson]

I had to resaw quite a lot of long boards with minimal waste allowance, so when I started getting drift I went in search of a reason and a solution.

First, I went with a carbine tipped 3/4" blade (ReSaw King), the largest my bandsaw could use. That didn't cure it.

After watching several videos, I was back to adjusting the tilt angle of my upper wheel to get the blade to run in perfect alignment to remove drift. I also bought a Carter Magnetic fence and F.A.S.T (Fence AlignmentSystem Tool).

I used the Carter tools (https://www.carterproducts.com/band-saw-products/band-saw-magfence) to identify the drift angle easily and to allow me to reasaw with the Carter fence instead of my bandsaw fence without drift affecting my work piece.

After successfully resawing all my long boards, I used the Carter fence to help me micro adjust the bandsaw tilt wheel to get the blade tracking perfectly parallel to the miter slot. This then allowed me to adjust my bandsaw fence.

Now I don't have any drift and can use either fence option.
Sounds like a lot of effort and $ to avoid spending a couple of minutes to adjust the fence to match the drift angle which will change if you change blades or cut curves.

[ChrisA Edwards]

Yes, but it achieved the desired results and now I'm happy with my bandsaw rather than being frustrated.

If I couldn't have got the drift figured out and just cut my project, plowing on ignorantly, getting 50% of useable wood out of each piece, I would have spent 10 times more in wasted material than what the tools cost.

I've used the Carter Magfence and the FAST pieces countless times for other things, so I'm not sitting with a one time use tool.

[Doug Garson]

Yes, but it achieved the desired results and now I'm happy with my bandsaw rather than being frustrated.

If I couldn't have got the drift figured out and just cut my project, plowing on ignorantly, getting 50% of useable wood out of each piece, I would have spent 10 times more in wasted material than what the tools cost.

I've used the Carter Magfence and the FAST pieces countless times for other things, so I'm not sitting with a one time use tool.

If it works for you great but I struggle to understand how it works. As I understand it the FAST system attaches to the body of the blade without touching the teeth
and allows you to set the fence parallel to the body of the blade. What good is that if your blade has drift and therefore does not cut parallel to the body of the blade?

[ChrisA Edwards]

Yes the FAST pieces have a magnet and a recess, to account for the teeth kerf, so it sticks to the blade. You then slide the Cater Magfence up to the FAST piece, that's on the blade, aligning it until it touches the MagFence and is parallel. Any slight touch of the FAST piece by the MagFence cause the FAST piece to wobble on the blade. Once you have the MagFence in position, you turn the magnet switches to lock it in place. You can then see the drift angle and compare the MagFence to the bandsaw fence to see how far out of alignment it is. You can then remove these two pieces, turn the saw one, make a slight adjustment of the blade tracking knob and check again.

This whole process took me about 10 minutes and I had eliminated my drift.

If I change blades and experience drift again, I just repeat.

It's nice knowing you can get to a drift free setting quickly and easily within a couple of minutes.

[John TenEyck]

That's putting the cart in front of the horse. Set the blade in the middle of the top wheel and adjust the miter slot parallel with the blade. Then the fence parallel with the miter slot. If the blade doesn't cut straight and parallel with the fence adjust it slightly with the top wheel adjustment until it does. If it still doesn't cut straight then the blade is bad or the wheels need to be aligned.

What you are doing is not getting drift free settings, it's adjusting to compensate for drift. That's OK if you have a dull blade, etc. but just have to finish a project, but forces you to repeat the procedure every time you change the blade and makes the miter slot of no value. Most people wouldn't want to have to adjust the fence on their TS every time they change blades and have the miter slot of no value.

John

[lowell holmes]

Neither do I. I have an after market rip guide for my bandsaw.

[ChrisA Edwards]

That's putting the cart in front of the horse. Set the blade in the middle of the top wheel and adjust the miter slot parallel with the blade.
John

John, if this was in response to me, I understand what you are saying, but I had no joy with just putting the center of the blade in the middle of the top wheel. The blade will track to where it wants to be, based upon the alignment of that wheel, adjusting the wheel tilt changes this. Changing to a different blade would possibly require aligning again.

So your method tune the table and fence to the blade, just using the tilt wheel adjusts the tracking of the blade. You just need something as a reference to see this fine adjustment. This is what the Cater system gives me.

Thinking about the Carter FAST pieces, you could easily replicate the use of these with a small round Rare Earth magnet and a small steel ruler and use the rulers to align the fence.


Each method gets you to the desired result.

I'm happy with mine since setting it up.

Taken this afternoon.

https://www.youtube.com/watch?v=M0WLypukpSY&feature=youtu.be

[John TenEyck]

Chris whatever works or you is fine; I'm glad you are happy with it. But your comments show you may not have given centering the blade on the upper wheel a fair shot. Of course the blade will move forward or backwards when you first put it on the upper wheel. That's why the tilt mechanisn is there; so you can adjust it so that the blade does in fact run on the center. No two blades are exactly the same, so every time you change blades you may very well have to adjust the tilt mechanism to keep the blade running there. But once you do that the blade will cut straight, or require no more than a minor forward/backwards adjustment to do so, with no need to adjust the fence for drift.

John

[Meryl Logue]

John, if this was in response to me, I understand what you are saying, but I had no joy with just putting the center of the blade in the middle of the top wheel. The blade will track to where it wants to be, based upon the alignment of that wheel, adjusting the wheel tilt changes this. Changing to a different blade would possibly require aligning again.

So your method tune the table and fence to the blade, just using the tilt wheel adjusts the tracking of the blade. You just need something as a reference to see this fine adjustment. This is what the Cater system gives me.

Thinking about the Carter FAST pieces, you could easily replicate the use of these with a small round Rare Earth magnet and a small steel ruler and use the rulers to align the fence.


Each method gets you to the desired result.

I'm happy with mine since setting it up.

Taken this afternoon.

https://www.youtube.com/watch?v=M0WLypukpSY&feature=youtu.be

That was a sweet cut. No doubt there.

[Rod Sheridan]

It’s only a factor if your saw is not properly adjusted or the blade needs replacement....Regards, Rod

[Lee Schierer]

My band saw used to have drift. I adjusted the fence to reduce it but couldn't eliminate it. It was suggested that I check out this video (https://www.youtube.com/watch?v=vNdrkmx6ehI). Before watching the video I had never considered that band saws like table saws are assembled in a factory but not precisely aligned. Most experienced woodworkers will confirm that their table saw worked much better when it was tuned up, so why don't we all tune up a band saw to align the table with the blade. We adjust the table on our band saw to be perpendicular to the blade yet many ignore the miter slot.

You can tune your band saw following the guidance in the video. I used the process from the video on my saw and my saw became a totally different machine. I could change blades when ever I wanted and it still cut drift free. I can use my miter slot and get cross cuts at 90 degrees. I can rip pieces of wood without them pulling away from or into the fence. I can resaw without wiggling the board all over the pace to stay on the cut line.

[Kevin Jenness]

Michael Fortune's method requires that the blade centerline runs on the upper wheel centerline- all well and good when using the same blade width all the time. In his original FWW article he said that he always uses 1/2" blades, and given that he has 8 bandsaws in his shop he could easily set each one up with a different blade width. The trick comes when changing blade widths- you need to adjust the upper wheel tilt to get the blade in the sweet spot. If using the miter slot is important to you then that is the way to go.

My saw has no miter slot and the guide setup precludes running all blades at the upper wheel's centerline, so I just adjust the fence to match the blade I am using at whatever angle works. I use this fence https://www.popularwoodworking.com/american-woodworker-blog/bandsaw-fence/ which has the advantage of being able to run on the right side of the blade when needed for bevel cut support.

[Doug Garson]

My understanding is that one way drift is introduced is when the teeth on one side are duller than the other as a result of cutting curves. So unless you use a dedicated blade for ripping and resaw and never cut curves with it, you will introduce drift. I had a blade with severe drift, resharpened it in about ten minutes with my Dremel and the drift was gone or at least dramatically reduced. For minor drift I adjust my shop made fence to compensate for it. Seems like adjusting the fence is a lot easier and intuitive than adjusting where the blade rides in the upper wheel, I keep mine with the the crown of the wheel just behind the kerf.