Band saw Blade drift

[Rorschach]

FWIW I don't really use the "Snodgrass Method". I did watch his video a long time ago and found that I was doing something quite similar anyway regarding blade/wheel positioning.

My saw is an Axminster 250 something, the bottom wheel was out of whack with the top wheel when I got it due to there being a bit of slop on the arbor, the addition of a thin washer fixed this problem and now they line up well.

I almost exclusively use 1/4" blades and once I got things set up I almost never have to adjust the guides. I remove the old blade, put the new on, tension it up and then adjust the top wheel until the gullet is roughly centred on the wheel and at this point it is just about touching the guide bearings, I add a touch more tension and then lock it down. Blade change only takes a couple of minutes now since I cut a slot in my fence guide so I don't have to remove it anymore.

I also am not a tuffsaws fanboy as some will have noticed. They do not last as long for me as axminster blades but I am currently trialing them on a longer term basis as I think their lower cost might just make them better value for money overall, this is yet to be proven in my case though.

 

[CHJ]

As a matter of interest, managed to eventually get to the bandsaw tasks I'd intended for today after lunch and out of interest had a look at Blade position and tyre condition.

The Tyres are Flat or at least have no sign of crowning now.
The current 1/2" blade is riding with teeth just forward of the tyre and clear of the wheel rim.
The Tyre shows signs of slight grooving in the front third of the tyre, presume from narrower blades that ride further back with teeth on the tyre.

Just been out and shifted the machine to look at the tension guide and it is indicating 3/4" so is at odds with my assessment of blades needs, might just be age of spring tensioner or an extra tooth on the blade.

 

[sunnybob]

Chas, youre flying in the face of every piece of bandsaw advice ever given with the blade that far forwards.
Dont tell me you have thinner blades in the same position?

 

[CHJ]

Chas, youre flying in the face of every piece of bandsaw advice ever given with the blade that far forwards.
Dont tell me you have thinner blades in the same position?

I did say:-

The Tyre shows signs of slight grooving in the front third of the tyre, presume from narrower blades that ride further back with teeth on the tyre.

As I've said, since initial setting up of the Bandsaw some 10 yrs ago and occasional post table tilting alignment checks, I only ever adjust Blade tracking for vertical fore and aft against the table, wherever it settles on the top wheel it stays.
One of the benefits of Flat tyres I guess is that the blade stays parallel to the table mitre slots wherever it settles fore & aft.

 

[powertools]

I have a small Inca and a larger Kity 613. Both have flat wheels and both run well with the blade running with the teeth just overhanging the front of the wheels.
If you have a bandsaw with crowned wheels you need to set it up with the middle of the blade running at the top of the crown and not the bottom of the teeth running at the top.

 

[woodbrains]

Chas, youre flying in the face of every piece of bandsaw advice ever given with the blade that far forwards.
Dont tell me you have thinner blades in the same position?

Hello,

No, tyres without a crown are set up so the teeth ride forward of the tyre. It is not common, but there are bandsaws designed that way. The teeth would chafe the tyres otherwise. Which is a good reason for NOT taking any notice of Snodgrass and tracking your blade central to tyres with a crown.

I have probably run more bandsaws in my life than most hobbyists have changed blades. Setting the band to run central to crowned tyres is fine. Setting the gullets to run on the centre of the tyre is nonsense, it will not prevent drift. Drift is eliminated in the set up of the machine and a sharp blade. Even tension has little effect on drift. If the saw is set so that when the table is bolted to it's trunnion, the rip fence cuts true, you have eliminated drift. Simple. I know for a fact that some respected professionals actually run their saws under tensioned. Set up right, it doesn't matter. I forgot to re-set the tension lever on my saw once and only realised after I had ripped a couple of boards. There was no drift, or else I would have been alarmed to the situation. We seem to be making a mountain out of all this. Snodgrass has to say something different, otherwise he has nothing to say; he is a salesman. And taking the table off every time you change a blade is the biggest load of nonsense I have heard. Not only is it cumbersome and inconvenient, it actually upsets the set up of the table to blade, which when done, prevents drift! You want to keep that set up untouched when the saw is working sweetly. Even Snodgrass doesn't tell us why he thinks the blade needs support at the teeth on the tyre, he just tells us it does and leaves it at that. There is no reason for it, the blade has no support along the entire length of the straight bits, tension and guides keep it running true. What has the position the teeth meet the tyres got to do with it?

Mike.

 

[memzey]

Bandsaw setups = new sharpening thread

 

[powertools]

Bandsaw setups = new sharpening thread

Not really, there are many ways to sharpen a blade but only two ways to set up a bandsaw depending if the wheels are crowned or flat.

 

[Terry - Somerset]

There are only two reasons I have experienced on a bandsaw that cause drift:

- blade getting blunt and/0r being forced
- cutting turning blanks which tends to wear the teeth on one side only

Mind you it is only a tiddler of a machine - 10" throat - and needs patience to cut anything vaguely close to capacity (about 120mm)

 

[memzey]

Bandsaw setups = new sharpening thread

Not really, there are many ways to sharpen a blade but only two ways to set up a bandsaw depending if the wheels are crowned or flat.

I was just having a laugh