band saw drift question

[mqbernardo]

Hi, just a quick question for the more experienced (than me, at least ) folks around here. I have a small 10" Axi bandsaw , aka piece of junk, but with a nice after market blade (from a respected and trusted seller). I found out that the BS preformed better with the blade running slightly behind the center of the upper tire. i don´t know much about BS subtleties (if here is such a thing), including drift, but this has worked for me.
I recently had to change the blade, and found out (to my expense) that i just could not get the BS to cut without drift. Blade was brand new, welding was fine and i tried putting it dead center on the tire, slightly forward and back and even overhanging the sides of the tire and it still cut with drift, always to the same side. After ruining some pieces of fine brazilian tulipwood i ended up switching to another blade and eventually got the machine to cut with minimal drift. So question is: is there something else i coul have done with the 1st replacement blade? could (as it appears) it be only the blade fault? any more tips?


thanks in advance,
Miguel.

 

[woodfarmer]

I don't have much experience using a bs, but tensioning the blade seems to make a difference and each blade needs a different tension. generally wider ones a lot more that the thin ones. But blades do differ. I have two sabrecut blades, one 3/8 and the other 3/4 The 3/8 cuts like a champion, the 3/4 not anything like as good.

but the blade needs to be true, vertically for and aft as well as up the sides. It also has to point towards the slot and be parallel with it.

Hope that helps, sure someone who knows better than me will be along shortly.

 

[Random Orbital Bob]

Try not to get side tracked by the position of the blade on the tyres. The upper wheel tyre, where you notice the tracking adjustment should be pretty much central. What a lot of people don't understand about band saws is that the reason the wheels are crowned is to aid central tracking. A bandsaw is basically a large flat belt pulley where the belt is metal and has teeth on one side. Of course you cant have a v groove to aid the channelling of the belt because it needs to be flat. That's where crowned wheels come in, they aid in the movement of the flat blade back to centre. So band saws are designed to have the blade track centrally on the wheel where the adjustment is (ie the top). It doesn't matter where it is on the bottom so long as its on the tyre. This does assume your wheels are in the correct plane. Lets assume they are for now because the two most likely causes of drift are:

1) poor blade quality/blunt blade even from new (this is easily and by far away the most usual cause)
2) blade tensioned incorrectly (usually under tensioned, causing poor beam strength so the blade doesn't stay straight in the cut)

A well tensioned bandsaw with a good quality blade and the right feed speed will cut straight without any of the guides even in place. I'm not advocating no guides, just making the point that the critical setup is blade quality and tension assuming wheels are co-planar.

You've mentioned your supplier is good....that leaves tension. How have you achieved your tension and what tests have you done to satisfy yourself its correct?

One last question on the blade....have you had acceptable results from a new blade before from the supplier you cite as good?

 

[dzj]

Lack of tension, sharpness or set can cause this. Also too many TPI is not good either.

 

[Baldhead]

I have two bandsaws, the smaller on is an Axi, when using Axi blades I had a lot of trouble tracking the blades and I just couldn't get the damn thing to cut right, I bought a couple of blades from Tuffsaws and it made a world of difference, easier to track and the cut was cleaner and straighter, I wouldn't buy blades anywhere else now.

Can I also recommend Steve Maskery's DVD's on the bandsaw, they show you how to set up your saw correctly, he even has a novel way of explaining what Bob has said above about where the blade should be on the tyre (Steve uses a beer barrel)

HTH

Baldhead

Edit - The beer barrel was empty (wonder who drank the contents........answer on a postcard :lol: )

 

[woodpig]

I read quite a bit about setting up a bandsaw and spent ages making all kinds of adjustments.
I could have saved an awful lot of trouble if I'd seen this first:

http://youtu.be/wGbZqWac0jU

Blade position (gullet on centre line) and tension is all I adjust now.

 

[Higon]

Thanks.. thats a very good video!

EDIT:
just spent this morning setting up the bandsaw as per the instructions on the video. I have to say I'm rather impressed! Can now slice 1mm flat slices from large chunks without any problems! Could never do that before.

Once again thanks Wood pig. Good find.

 

[blackrodd]

AHH! Mr Snodgrass, He is without doubt, the man.
I'm always amazed at the speed in which he cuts those bandsaw boxes.
Rodders

 

[mqbernardo]

thanks for the replies and the video. I have mr. Maskery´s DVD somewhere but can only find an empty case - i blame my kids!

will look at the video closely, seems just what i need!


best,
Miguel.

 

[Higon]

AHH! Mr Snodgrass, He is without doubt, the man.
I'm always amazed at the speed in which he cuts those bandsaw boxes.
Rodders

made me feel proper inadequate... he didn't hang around on the reindeer either.

 

[Ghengis]

Used his method and its transformed my bandsaw

 

[Rhossydd]

Try not to get side tracked by the position of the blade on the tyres.

Indeed. The 'run the gullet of the teeth' is repeated often here, but on some saws that's simply not possible.
The instructions supplied by both Startrite and Axminster say to run the blade on the centre of the wheel. Startrite specifically says not to run the blade on the back of the wheel and if you did you wouldn't manage to fit a decently wide blade on anyway. Are the manufacturers really not to be trusted with their advice on how to set up their machines ? I'm not convinced.

 

[Steve Maskery]

This is a simple tracking and tension issue. You have lot of good advice above, but I will add a bit more. FIND YOUR DVD!!! It will solve your problem.

The point is that the blade at table level needs to be North-South. Adjust the tacking until it is, and don't worry about where that leaves the blade. As long as it's still on the wheel...
S

 

[Higon]

Used his method and its transformed my bandsaw

+1

 

[woodpig]

The reason for the blade position is mentioned again here.

http://thewoodworkersnews.com/2012/11/bandsaw-blade/