Bandsaw drift

[Grahamshed]

I am looking for a way to deal with bandsaw drift.

Some youtube videos claim that if the teeth of the saw are in the middle of the wheels then you dont get drift, but if i set mine up that way my guides do not go back far enough.

Most other vids show a way involving making a free hand cut but my eyesight is such that I doubt I could follow a straight line closely enough to be sure I was seeing the result of drift and not just inaccuracy.

One vid said you could make a short cut with the wood against the fence and then check the back of the cut to see which side of the blade had a gap between it and the wood and then adjust the fence accordingly. Anyone tried this ?

Or does anyone know another way that does not involve good eyesight ?

 

[Steve Maskery]

Graham
Assuming you have a good blade you should not need to adjust the fence at all, it should be be square to the table. Drift can be eliminated (not just compensated for) by ensuring that the blade rides in the right position on the wheel. That may or may not be dead centre. You may also find that adjusting the tracking knob has no effect for ages and then all of a sudden it all changes. You just have to get to know your machine.
But skewing the fence to accommodate drift is a very poor substitute for setting it up properly, not least because it prevents effective use of the mitre slot.

 

[monkeybiter]

One vid said you could make a short cut with the wood against the fence and then check the back of the cut to see which side of the blade had a gap between it and the wood and then adjust the fence accordingly.

I would have thought this method would require better eyesight than manually finding the correct angle.

 

[James C]

For one of the blades that I use on my bandsaw I have to let it ride slightly back from centre on the wheel in order for it to cut completely straight.

 

[Lord Kitchener]

Have you considered a) getting more light onto the cutting area and b) using on of those magnifying glasses with a flexible stem and a magnetic base that Axminster amongst others, I expect, do? I use on myself for setting scales etc, and very handy it is too. Those measures might help overcome your eyesight problem and would allow you to steer the material against a re-saw fence

 

[Grahamshed]

One vid said you could make a short cut with the wood against the fence and then check the back of the cut to see which side of the blade had a gap between it and the wood and then adjust the fence accordingly.

I would have thought this method would require better eyesight than manually finding the correct angle.

Yes, but it can be done with the blade stopped and a big magnifier behind it.

A magnifier in front of the blade doesn't really work for me as I have to get to close. Most work I do while not exactly done by touch does rely on it to a fair extent.

 

[Grahamshed]

Graham
Assuming you have a good blade you should not need to adjust the fence at all, it should be be square to the table. Drift can be eliminated (not just compensated for) by ensuring that the blade rides in the right position on the wheel. That may or may not be dead centre. You may also find that adjusting the tracking knob has no effect for ages and then all of a sudden it all changes. You just have to get to know your machine.
But skewing the fence to accommodate drift is a very poor substitute for setting it up properly, not least because it prevents effective use of the mitre slot.

Good point about the mitre slot Steve.
Do your DVDs go into this in any depth ? and how would you deal with it if the guide assemblies dont move back as far as you need ?

<edit> Guessing, the wheels can be moved to bring the blade forward ?

 

[Steve Maskery]

I'm not sure how much I can say openly without breaking forum rules, but the DVD will enable you to set your BS up correctly, eliminating drift and getting a good quality of cut. Just read what others have said, not just me! Money-back guarantee etc, etc.

I've only once come across a machine where the blade guides wouldn't go back far enough, and in that case it was a straightforward case of cutting away part of the blade guard with a Dremel, where it fouled the movement of the guide assembly.

EDIT - Just to be unambiguous, the specific point of using a mitre fence is covered.

 

[CHJ]

Graham, I may have missed a thread/post somewhere, but what machine, Make and Model bandsaw do you have, might help with info. from other owners re: guide travel.

Must say with my 14" SIP machine if I get drift it's time to change a worn blade, put anything sharp on and adjust the guides for vertical (square to table) blade and it will cut 2-3mm slices against the fence no problem.

 

[Grahamshed]

hi. Steve, I will be sending for the DVDs, didn't mean for you to break any forum rules

Chas - Its an Axi 400N. When I first got it 2 or 3 weeks ago I changed the blade and set the new one in the middle of the wheel but the guides didn't have enough travel backwards to clear the teeth. They were not fouling anything, just not enough travel.
I solved this by moving the ( half inch 4tpi ) blade so the front of the teeth were maybe 5 or 6 mm in from the edge of the rubber tyre and although the cut wasn't brilliant it wasn't to bad and there was no noticeable drift, or at least I could cut a similar 2 or 3 mm slice against the fence.

It was only when I put the 24 tpi blade on (mentioned in another post) that drift was obvious when testing on 10mm oak ( not what I actually got the blade for ) but that ( as I have been told ) is probably down to sawdust clearance, or the lack of it.

I will see when I put the other, or another, blade back on but having to mess about to much when changing blades is going to be a PITA

 

[CHJ]

Most of my blades are of a similar thickness so only have to adjust the rear support on my SIP so the chore level is minimal.

Very surprised that there is not enough fore-aft adjustment to accomodate a 1/2" blade, the side bearings alone must be near 1/4" alone and the machine should take a 3/4" blade with ease.

 

[Grahamshed]

I dont thinnk it was the side bearings so much, it was the back bearing couldn't move back far enough.

 

[CHJ]

If your machine is constructed as per the image, which shows what looks to be 3/8"-10mm blade, then the rear bearing mounting shown has at least the width of the fixing bolt left in the adjustment slot.

Can you post a picture of your blade support from the side view with the 1/2" blade fitted? (equivalent detail to the above image)

 

[Grahamshed]

I will get some pics in the morning. That would appear to be exactly the same as mine but I am more concerned with the bottom bearings.

I am beginning to wonder if I did, or missed, something stupid when I first set it up ( having never been close to a bandsaw before ) because while what I said above is true, it doesn't appear to make any sense that while saying I had to move the blade to clear the teeth from the guide bearings I also couldn't move the back bearing back far enough.

 

[Alder]

I am picking up on an old thread of bandsaw drift.
Does anybody have experience of the Kreg Rip fence
Thank You
Russell Evans
:?:

 

[Steve Maskery]

Hi Alder, welcome to the forum.
No, not specifically, but Kreg stuff generally is top-notch. It won't cure drift though!
S

 

[Alder]

Thank you for the reply.
My query was based on the matter that Kreg claim it is very adjustable which my Metabo is not.
Russell

 

[Steve Maskery]

It's not best practice to fix drift by adjusting the fence. The fence should be set to true north and drift tuned out by altering the tracking. It's all very well skewing the fence for ripping, but your crosscuts, or anything else that relies on the mitre slot, will be out of true.
S

 

[RogerM]

I'm not sure how much I can say openly without breaking forum rules, but the DVD will enable you to set your BS up correctly, eliminating drift and getting a good quality of cut. Just read what others have said, not just me! Money-back guarantee etc, etc.

I've only once come across a machine where the blade guides wouldn't go back far enough, and in that case it was a straightforward case of cutting away part of the blade guard with a Dremel, where it fouled the movement of the guide assembly.

EDIT - Just to be unambiguous, the specific point of using a mitre fence is covered.

I held back from buying Steve's DVDs for ages. False economy. Just do it. Your bandsaw will sing with happiness as it cuts dead straight!

 

[markturner]

I just had a very frustrating few hours the other day battling with my new bandsaw. It's a Felder so pretty good quality and when I got it new about 6 months ago, worked fine, I have changed the blade twice now. The last time ( few weeks ago) I went from an approx 9mm blade to a wider ripping blade ( using Ian at Tuffsaws blades BTW). After fitting that, it would not cut straight, whereas it was perfect before.

So I very carefully went through everything, could find no issue, apart from the new blade rode nearer to the front of the wheels. I do have Steves DVD's, but on this occasion, as they were not handy, trawled you tube and found a couple of guides to eliminate drift. Following said advice, I adjusted the tracking so the wider blade ran with the gullet of the teeth on the centre of the wheel, IE teeth just not touching the rubber.
It still drifted. So following further advice, I did the old freehand cut and adjust the fence to follow the line trick. My fence is now maybe 10mm out of true across the table, a lot. But the saw cuts straight.

So my queries are, why the difference between the two blades? Also finding it really tricky to gauge the correct tension on the thicker wider blade - when testing for deflection, I can adjust it a long way without being able to detect any difference, so I am not really sure if it's at the correct tension.

Going to go home and watch Steves videos, but I feel that something is not right still......but cant for the life of me see what.

Cheers,