Aligning bandsaw table to the blade

[Meryl Logue]

This is a riff on a much-discussed topic.

I bought one of those gizmos to see how far off my blade is. (A lot) Then I looked in my Jet owner manual for how to adjust the table (miter slot). Nothing. I wound up adjusting the fence to the blade, which is fine, worked well. Almost enough slack, but I got it close, and my cut was smooth and lovely.

1) This precludes using the miter slot/track for a holding jig for making boards out of logs
2) Made me wonder if blade position on the wheel would affect alignment
3) Led to the discovery of badly cracked tires (to be replaced)
4) Which further led to the discovery of an out of round/ out of balance lower wheel as evidenced by carefully holding a soapstone to it inside and outside (NO BLADE!). The marks were in very close alignment inside and out.

This saw dates from 2005, very little use. It had the original blade on it.

Comments?

[Alan Schwabacher]

Yes, adjusting the tracking to vary where the blade rides on the wheels will affect the cut line. Use that to make it parallel to the miter slots.

[Edward Weber]

Adjusting the blade tracking is the proper method to align the blade.
All the gizmos and gadgets are a waste of time and money IMO

[Paul F Franklin]

If the wheels and/or tires are crowned then adjusting position of blade on tires with the tracking adjustment will change alignment. If the wheels/tires are flat I don't think it will make much difference. My Laguna 18BX table slot was not aligned to the blade and like yours, no info in manual on adjusting the table alignment. But it was pretty easy to figure out what to loosen to shift the table and I was able to align it close enough using the magnet and rule trick. If you're going to do this, align the table first, then the fence. If you shift the table, check it over the full range of motion to make sure the table insert doesn't hit the blade at any angle.

[Jim Becker]

Adjusting the table to be perpendicular to the blade is what I consider a critical need. But the cut line, itself, is going to change over the life of a blade. That's where an adjustable or point fence comes into play.

[Edward Weber]

To be clear, I was taking about Bandsaws with crowned tires.

[Lee Schierer]

This is a riff on a much-discussed topic.

I bought one of those gizmos to see how far off my blade is. (A lot) Then I looked in my Jet owner manual for how to adjust the table (miter slot). Nothing. I wound up adjusting the fence to the blade, which is fine, worked well. Almost enough slack, but I got it close, and my cut was smooth and lovely.

1) This precludes using the miter slot/track for a holding jig for making boards out of logs
2) Made me wonder if blade position on the wheel would affect alignment
3) Led to the discovery of badly cracked tires (to be replaced)
4) Which further led to the discovery of an out of round/ out of balance lower wheel as evidenced by carefully holding a soapstone to it inside and outside (NO BLADE!). The marks were in very close alignment inside and out.

This saw dates from 2005, very little use. It had the original blade on it.

Comments?

I aligned my band saw table to the blade and I no longer have drifting problems, even when I change blades. I used this link to do the job (https://www.youtube.com/watch?v=vNdrkmx6ehI).

[glenn bradley]

Bandsaw threads are often as rife with voo-doo as Saw Stop, Festool, and sharpening threads. Many, many folks have found what works for them; they are all correct. A lot of these folks think they have the definitive answer; they are probably not correct :D. Your post touches on a lot of areas but it seems you have found a method that works for you so I would stop there.

Blade position on a crowned tire does alter alignment with another fixed plane.
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Adjusting the fence to compensate for "drift" is another way to go.

You mention the miter slot. As with router tables there are those of us who use the miter slot and others who wonder why. This will vary with how completely you use the tool as in the case of many 14" 'do it all' machines versus dedicated curvy-cutters and ripping bandsaws.

I aligned the blade to the miter slot using a wide blade, a magnet and a rule. First to the miter slot.
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Then aligned the fence.
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As mentioned, blade wear or use beyond the reliable life of the cutter will result in tracking issues and there are all sorts of ways (including an expensive fence) to handle that until your new blade arrives. I keep spares of each commonly used blade and order the replacement when the spare goes on the machine.

Bandsaw blades are wear parts like sandpaper. If you try to milk extra work out of a failing item you can spend more time fixing the errors it provides than it is worth. I find I get much better and more repeatable results with a cutter that isn't past its "good" life. I do keep worn blades around as 'thrashers' for unknown or unforgiving material.

[Edward Weber]

I look at it this way,
I have two bandsaws both with crowned wheels/tires. On both my saws, the table is mounted solidly to the frame, not designed for adjustment. The fence is mounted to the table solidly and aligned to the miter track, not designed for adjustment. The blade is mounted on the wheels/tires which are designed to be adjusted via the tracking adjustment mechanism.
So, not to sound like a jerk but why would I fiddle around with things that aren't designed to be adjusted?
The number of gadgets available to eliminate "blade drift" is staggering. If you set your saw up properly in the first place, you effectively eliminate the need for all those gadgets.
Once the blade is running parallel with the fence and by extension the niter slot, you can use other fixtures and sleds with better accuracy.

There are many opinions on this subject but there are also objective facts and laws of physics/geometry that can't be ignored.

As has been said, whatever works for you in your shop. I only provide an alternative that works for me and try to explain why.

Cut straight, be safe

[Curt Putnam]

I use this Bandsaw Buddy from Axminster and find it to be very effective.
https://www.axminstertools.com/us/ujk-technology-bandsaw-buddy-101807?glCountry=US&glCurrency=USD

[Bruce Wrenn]

Adjusting the table to be perpendicular to the blade is what I consider a critical need. But the cut line, itself, is going to change over the life of a blade. That's where an adjustable or point fence comes into play.


And that's the easiest adjustment to make. Take a board about 4" high, and make just a kerf cut into it. Take same board and place kerf cut behind blade. If blade doesn't align, the adjust and try again.

[Eric Arnsdorff]

I've been working on improving my Grizzly 16" bandsaw for resawing and such.
One of the guys at Woodcraft suggested watching this Alex Snoddergrass of Carter Products:
https://www.youtube.com/watch?v=wGbZqWac0jU

I did what he did on my bandsaw and I've only did one test cut but I was able to cut a test piece 0.10" thick off of a 1.5"x8" board. The worst the thickness varied (excluding blade ripple marks) was about 0.015". It was about 20" long. That was the best I've ever done with it. We'll see if that works on the soft maple I'm resawing. My first round before tuning it up ended up losing a number of my boards due to varying thicknesses.

Alex claims drift and such isn't a problem with a properly tuned saw. And it is a quick tune-up.

BTW - My saw is a 1999 Grizzly 16" G1073. It is a decent saw but is not a "tight" construction and still has all the original guides and such which leave a lot to be desired.

[Randy Heinemann]

I'm not really sure what the gizmo you bought was, but I have never had any problems with alignment either at 90 degrees to the table or 90 degrees to the miter slot. Whenever I change blades, and sometimes in between, I go through the setup process detailed by Alex Snodgrass from Carter Products. I realize that this set of steps is meant for resaw bandsaw setup, but the steps have always resulted in everything being setup properly including both the blade squareness to the table and the slot. Now maybe I'm just lucky but I doubt it. I also have something similar to the Axsminster jig referred to in the this post (mine is from Carter) but I don't use it for that purpose; only for getting an approximate distance from the blade to the fence for resawing. I also don't use the factory fence which came with my saw (Rikon). I could never get their fence to lock down square even though they supplied me with a replacement during warranty. Instead I use Cadter's MagFence which allows me to lock the fence down exactly where I want it with the 2 integral magnets. It is square to the table and to the slot (which for resawing probably isn't essential, only for other rips).

In case you're interested in the Alex Snodgrass (Carter) video, it's all over the internet on YouTube and, I think, on Carter's site. It's never failed me.

[Doug Garson]

Adjusting the blade tracking is the proper method to align the blade.
All the gizmos and gadgets are a waste of time and money IMO
I agree the gizmos and gadgets are a waste but you are assuming the able is properly aligned and the blade is good. If the table is off either because it was not properly aligned when originally installed or knocked out of alignment when moved or in use then that needs to be corrected. In my experience though, the main source of drift is the blade itself, I had a blade that drifted badly, I sharpened it with a Dremel and metal cut off wheel and the drift is gone.

[Edwin Santos]

I look at it this way,
I have two bandsaws both with crowned wheels/tires. On both my saws, the table is mounted solidly to the frame, not designed for adjustment. The fence is mounted to the table solidly and aligned to the miter track, not designed for adjustment. The blade is mounted on the wheels/tires which are designed to be adjusted via the tracking adjustment mechanism.
So, not to sound like a jerk but why would I fiddle around with things that aren't designed to be adjusted?


Are you certain the table mounting holes in the trunnions of your bandsaw(s) are not oversized?

The table adjustment procedure is to loosen not remove these bolts, tap the table into the desired alignment position with a mallet, then tighten the bolts.

The video Lee linked demonstrates what I am trying to describe at about 7:45 of the video.

[Alan Kalker]

Thanks Lee for the link. Michael centers the center of the blade on the center of the wheel. I’m pretty sure Alex Snodgrass demonstrates proper centering as placing the gullet of the blade on the center of the wheel. Which is correct?

[Lee Schierer]

I have seen Alex several times in person and even talked with him at length. His method works to a degree, but I still had problems with drift. Since I aligned my table, I've not had drifting problems resawing nor difficulty cutting circles with my circle jig. I use my bandsaw more now than ever before.

I center the blade on the upper wheel.

[Edward Weber]

Of course there is some play in the assembly for rough alignment.
I'm trying to follow the thinking here.
Put a blade on the saw and center it, then align the table to it?
If that's the case fine, let's say I do that when I first setup my saw, The problem is, is that every blade is different and doesn't care that you aligned your table to the first blade. There is no guarantee when you change blades that every one will track where the first one did.
The tracking adjustment is there for a reason, to adjust the blade position to cut parallel to the miter slot/fence, not to keep the blade directly centered on the upper wheel.

My point is once the saw is set up (ballpark aligned) the fine adjustment is done by the tracking adjustment. Your not going to re-align the table every time you change a blade are you? I know some people adjust their fence each time they change blades, which is much the same thinking.

I don't understand aligning something that is fixed (table or fence) to something that is moveable (blade)

[Edwin Santos]

Of course there is some play in the assembly for rough alignment.
I'm trying to follow the thinking here.
Put a blade on the saw and center it, then align the table to it?
If that's the case fine, let's say I do that when I first setup my saw, The problem is, is that every blade is different and doesn't care that you aligned your table to the first blade. There is no guarantee when you change blades that every one will track where the first one did.
The tracking adjustment is there for a reason, to adjust the blade position to cut parallel to the miter slot/fence, not to keep the blade directly centered on the upper wheel.

My point is once the saw is set up (ballpark aligned) the fine adjustment is done by the tracking adjustment. Your not going to re-align the table every time you change a blade are you? I know some people adjust their fence each time they change blades, which is much the same thinking.

I don't understand aligning something that is fixed (table or fence) to something that is moveable (blade)

The thinking is basically the same as the conventional method of tuning a table saw. The arbor is fixed, so loosen the bolts and adjust the table so the miter slot is absolutely parallel to the blade. Then adjust the fence so it is parallel to the miter slot. When you change blades, the blade plate will be in the same plane even if the blades themselves have different tooth profiles.

So taking this procedure to the bandsaw, if you are tracking every blade in the center of the wheel (top of crown), then the band body is in the same plane. So when you adjust the table miter slot to this plane, and adjust your fence to the miter slot, there should be no drift, and your results should be consistent from blade to blade. At least that's been my experience. The tracking function is only to get your band centered on the wheel. I might add, that after discovering this tuning approach, my tracking adjustments are minimal, oftentimes none.
Anyway, that's the thinking in answer to your question. I accept that there are other approaches, and I'm not trying to talk you out of whatever method works for you.

The only time I can remember having problems is when the blade had a bad weld and was not running true.

[Edward Weber]

The thinking is basically the same as the conventional method of tuning a table saw. The arbor is fixed, so loosen the bolts and adjust the table so the miter slot is absolutely parallel to the blade. Then adjust the fence so it is parallel to the miter slot. When you change blades, the blade plate will be in the same plane even if the blades themselves have different tooth profiles.

So taking this procedure to the bandsaw, if you are tracking every blade in the center of the wheel (top of crown), then the band body is in the same plane. So when you adjust the table miter slot to this plane, and adjust your fence to the miter slot, there should be no drift, and your results should be consistent from blade to blade. At least that's been my experience. The tracking function is only to get your band centered on the wheel. I might add, that after discovering this tuning approach, my tracking adjustments are minimal, oftentimes none.
Anyway, that's the thinking in answer to your question. I accept that there are other approaches, and I'm not trying to talk you out of whatever method works for you.

The only time I can remember having problems is when the blade had a bad weld and was not running true.


Here's where I slightly differ with this method.
On a tablesaw, mounting a blade (fixed) and adjusting the table to it, makes sense.
On a bandsaw however, the blade is not fixed, yes it's mounted but it is not fixed. By it's very design, the tracking is meant to align the blade for proper cutting. How are you gauging "putting the blade in the middle?

which brings me to tracking every blade to the center.
People are obsessed with the center of the upper wheel, why?
Put the blade in the center. no put the gullet in the center, no turn around three times and, you get the point. Not to mention where most people look at "center", at the 3:00 position is not where it matters. This is where the blade is leaving the wheel. If you really want to see where the blade is riding, you need to look at the 12:00 position
The top wheel is crowned and tilts, therefore no matter where the band is riding, it's being driven in exactly the same way as if it were in the dead center. In the earlier post I showed the diagram of how/why you would adjust the tracking, this is not opinion, this is geometry and physics.
When you replace a belt on a belt sander, do they all just track perfectly or do you need to adjust the tracking?
I agree that once your saw is in "general alignment", (it seems we all get there differently) mounting and tracking a blade into alignment should be a short process.
When I originally set up my saws, I mount the table and square the miter slot with the lower wheel, which is a fixed plane to reference from. Then align the fence parallel to the miter slot. I have never had to or would change these. Each blade over the years get mounted into the general position (roughly centered) and aligned by tracking and making test cuts. this takes very little time for me. When everything is set, I could not possibly care less if the blade is not perfectly centered in the upper wheel so long as the resulting cut quality is straight, every blade is different and may ride in a slightly different area of the wheel.
I should note that when I say use the tracking adjustment, I'm usually am talking about small adjustments, 1/8 or 1/4 turn at a time. Once you're in the ballpark you should not need to make drastic adjustments unless you've changed something else.
We will all have to agree to disagree sometimes, be safe, cut sraight

[Edwin Santos]

Here's where I slightly differ with this method.

We will all have to agree to disagree sometimes, be safe, cut sraight

Total agreement with that last part.
I'd say you love your Porsche, and I love my Ferrari.

[Rod Sheridan]

The thinking is basically the same as the conventional method of tuning a table saw. The arbor is fixed, so loosen the bolts and adjust the table so the miter slot is absolutely parallel to the blade. Then adjust the fence so it is parallel to the miter slot. When you change blades, the blade plate will be in the same plane even if the blades themselves have different tooth profiles.

So taking this procedure to the bandsaw, if you are tracking every blade in the center of the wheel (top of crown), then the band body is in the same plane. So when you adjust the table miter slot to this plane, and adjust your fence to the miter slot, there should be no drift, and your results should be consistent from blade to blade. At least that's been my experience. The tracking function is only to get your band centered on the wheel. I might add, that after discovering this tuning approach, my tracking adjustments are minimal, oftentimes none.
Anyway, that's the thinking in answer to your question. I accept that there are other approaches, and I'm not trying to talk you out of whatever method works for you.

The only time I can remember having problems is when the blade had a bad weld and was not running true.

Yes, exactly how I set them up.

Regards, Rod

[Edward Weber]

I will simply post a quote from Micheal Fortune, who many of you have cited as an authority on this subject. https://www.finewoodworking.com/2018/07/16/two-fixes-for-bandsaw-drift
"
When I bought my bandsaw in 1974, I set the fence parallel to the miter-gauge slot in the table, and I haven’t had to adjust it since. The reason is that I use the tracking adjustment on the upper bandsaw wheel to align the blade. A nightmare of fence adjustments ensues if each new blade is allowed to track differently.
Simply by keeping the centerline of the blade (regardless of width) in line with the centerline of the upper wheel, I am able to keep the blade aligned correctly at the blade guides.
The relationship between tracking the blade on the centerline of the upper wheel and having the fence aligned parallel to the miter slot should produce a kerf with equal space on either side of the blade.
Much has been made in books and articles of the alignment of the two wheels to each other. In my shop and in my travels to schools around North America, I have never found this to be a problem. Tracking the blade properly on the upper wheel has always been enough, except in the case of a severely damaged bandsaw. "

In a nut shell. Yes put the blade in the center and adjust the tracking until you achieve a straight parallel cut.
He does not go into what he means by "center"
Personally I roughly center the band, the flat potion of the blade. This is the part of the blade designed to make contact with the tire, drive the blade and adjust direction via the tracking mechanism. The teeth and/or the gullet should not come in contact (as little as possible) with the tire.

[Jim Becker]

I'm curious about what Michael would advice for folks who have bandsaws that feature flat (not crowned) tires where we run the teeth just off the edge of the wheel for tracking...