How do you throttle a Bandsaw

[david123]

I have had a SIP 14 for quite a while now, for 3 or 4 years and have used it a
lot for most jobs, and found it perfect so far for everything I require of it, including re-sawing hardwood.
I have been pulling my hair out today trying to get it to re-saw a piece of oak 160 X 16 x 7cm.l bought a new saw blade recommended by Ian at tuffsaws. I have completely reset and adjusted the bandsaw fitted my higher fence to accommodate the Oak reset the fence, checked that the oak was square and the fence, blade was horizontal and vertical to the bandsaw table,I even did the flutter test. Reset the guid bearings top and bottom and the ones at the rear, could find no deflection anywhere on the blade.
It rip Cuts perfectly, but every time I try to re-saw anything it will not stay parallel to the fence it wanders off to the right as soon as it passes through the blade. I can't think of what to do next.
I think I must have got myself in a loop and it's driving me nuts. Any advice to put me out of my misery? Or any experts live near enough to come over and point me on the right direction.

I think I need a drink #-o

 

[Steve Maskery]

Hi Dave
I have a couple of q's for you:
1 What size is the blade (width, thickness, no. teeth)?
2 Do you mean
a) the workpiece wanders to the right (i.e. away from the fence) or
b) the blade wanders to the right (pulling the workpiece tighter in to the fence)?

160mm is quite a deep cut for a bandsaw. It's a bandsaw, not a resaw. So setup has to be perfect. The limiting factor on a consumer BS is often not the distance under the blade guides, but the ability of the saw to tension a big blade sufficiently, and tension is important for thick cuts, because the wood itself offers so much more resistance. So that's why I'm interested in the blade.

If the answer to q2 above is a), then try tilting the wheel forward at the top a tad. If the answer is b), tilt it back a bit further. The thicker the cut, the less tolerance there is on the tracking.

S

 

[Racers]

Is the blade running in the centre of the wheels?

Pete

 

[woodpig]

Try putting the back of the gullet (of the blade) on the centre line of the top wheel and see if that works.

 

[AJB Temple]

On the occasions in the past when I have had this trouble (and with set up correct) the answer has been either
1 Blade was not tensioned anywhere near enough
2 Blade was too narrow or had too many teeth so the waste was not being cleared effectively
3 I was overworking the saw

 

[Beau]

Is the fence set at a slight angle to the one the blade wants to cut? I find you can get some variation with blades so for important cuts I do this.

Take a peace of reasonably long clean grained scrap say 50mm thick. Mark a parallel line down one side and then freehand cut along the line until it is running down the length of the fence but not touching it. Now being carful not to change its angle put a couple of clamps on this piece front and back on the table. Now set up your fence system so it runs parallel to the scrap.

Hope that makes sense

 

[Mike Jordan]

Hi David
When you say you have set the fence does this mean that you have lined it up with the mitre fence slot? I'm not familiar with your saw but some can have the table bolted down slightly out of true with the blade, this causes not problems with thinner stock while using a good blade but can cause drift in a deep cut. If you can move the fence after making a trial cut so that the fence is truly parallel to the cut line it may solve the problem.
Mike

 

[david123]

Hi Steve / Peter
The blade is one of Ian's superTuff FastCut bandsaw blades 3 PTI 3/4 inch. Yes it's (A) .
The wheels are flat topped and not crowned and I usually start with keeping the blade to the center. I have successfully used it to re-saw this sort of thickness before, it's a SIP 01444 with150 watt motor. I will try moving the blade on the crown forward in the morning Steve, I did play around with ajusting the tilt, but I will concentrate on that alone in the morning thanks for the imput guys.
Much appreciated.

 

[david123]

Just seen the other posts that have been submitted while I was typing
Thanks Beau, yes I always set up that way with a new blade. And thanks Mike, I understand what you are saying, like most new machines I check them before use, but I got so frustrated today I checked it again.

 

[NazNomad]

The wheels on my Kity aren't crowned. they say to install the blade with the teeth over the front edge of the wheel.

I think there's been a discussion on here about this before, something to do with the way the actual teeth are (or are not, I forget) supported.

 

[david123]

Hi Naz
Depends on the blade, they can (as, like you, I have read ) that they can damage the tyre with the teeth, and so only the gullet should be on the tyre.

 

[Steve Maskery]

No-one, including manufacturers, has yet been able to explain to me how you can have the teeth off the front of the wheel and still get it to track properly. As far as I can see, the two are mutually exclusive. I think it is one of those things that gets perpetuated without any understanding, if I'm honest. Yes, it might cause less damage to the tyres, but what use is that if you can't cut straight?

And the business between flat and crowned is not as important as you might think, because even a flat rim behaves as if it is crowned once it is tilted. I think you have my DVDs, don't you? Have another look at the section on Tracking, where I go down the pub That should help.

I think you are probably using your saw at its limits, but I also think you will prevail! Good luck.

 

[custard]

I have been pulling my hair out today trying to get it to re-saw a piece of oak 160 X 16 x 7cm.

Those dimensions look a bit weird, so let's see if I've got this straight, you're cutting through 160mm of Oak? And you're trying to turn a board that's 160mm x 70mm into two boards that are both 160mm x 35mm (less a bit for the kerf)?

I'll assume that, because your day to day ripping is acceptable, you're okay setting up your bandsaw. In that case there are two things that might scupper your chances on this particular job,

1. You're feeding the workpiece through the blade way too fast. The gullets are getting choked up with packed in sawdust and consequently the blade wanders off the line. The gullet must not be full of sawdust when it emerges at the bottom of the cut, which obviously requires a much slower feed rate on thicker boards. I cut loads of hardwood veneers on my bandsaw with a 1/2" 3 tpi blade, the results are superb, but I nearly pass out from boredom while I'm doing it because the workpiece has to go through the blade at an absolute crawl. Get the radio on and reconcile yourself to a long slow job.

2. The workpiece is wet, or at least it may be dry on the outside but it's still too wet on the inside, so as soon as the cut is made the two halves twist and push away from the fence. If the workpiece was perfectly square going in, but is at all cupped, crook, or in wind coming out, then that's your problem. Leave the wood in stick in a dry environment for several weeks, better a couple of months. Seriously, I sort out the stock I'll use for critical components like drawer sides a year or more in advance.

If you're eager to crack on with a job this may seem tedious advice but as I always say, in woodworking the dice are really heavily loaded and the tortoise will beat the hare every single time.

Good luck!

 

[memzey]

No-one, including manufacturers, has yet been able to explain to me how you can have the teeth off the front of the wheel and still get it to track properly. As far as I can see, the two are mutually exclusive. I think it is one of those things that gets perpetuated without any understanding, if I'm honest. Yes, it might cause less damage to the tyres, but what use is that if you can't cut straight?

And the business between flat and crowned is not as important as you might think, because even a flat rim behaves as if it is crowned once it is tilted. I think you have my DVDs, don't you? Have another look at the section on Tracking, where I go down the pub That should help.

I think you are probably using your saw at its limits, but I also think you will prevail! Good luck.

Off topic but I love your new avatar Steve. At times like this humanity needs to show solidarity against those that seek to ruin us.

 

[Glynne]

Hi Dave,
I had intermittent problems in resawing until I followed Custards advice regarding feed speed.
If you feed your wood through REALLY slowly, as in you want it to take as long as possible, it does work amazingly well.
For some strange reason I like knarly old English oak which is a pig to resaw but I can get 1mm veneers quite easily, but not quickly!
Same blade but on a Record BS350 but the slow speed is critical.

 

[woodbrains]

No-one, including manufacturers, has yet been able to explain to me how you can have the teeth off the front of the wheel and still get it to track properly. As far as I can see, the two are mutually exclusive. I think it is one of those things that gets perpetuated without any understanding, if I'm honest. Yes, it might cause less damage to the tyres, but what use is that if you can't cut straight?

And the business between flat and crowned is not as important as you might think, because even a flat rim behaves as if it is crowned once it is tilted. I think you have my DVDs, don't you? Have another look at the section on Tracking, where I go down the pub That should help.

I think you are probably using your saw at its limits, but I also think you will prevail! Good luck.

Hello,

Steve, the first bandsaw I had was a Kity 613 and always set it up, as per instructions, with the teeth set off the front of the flat tyre. At the time I was reading how to correct bandsaws for drift, setting fences out of parallel to compensate for the out of straight cut line etc. and I was thinking, what is balde drift, I've never experienced that? It may be counter intuitive, but it does work, believe me.

Mike.

 

[Steve Maskery]

Exactly. You have to set the fence out of parallel to compensate.
So how do you get a square crosscut? You can't.
Skewing the fence is a very second-rate way of compensating for drift. Eliminating the drift in the first place is a MUCH better way of setting up a bandsaw!
OK, if the natural position of the blade is true north by nature, then you don't have a problem, but you are very lucky indeed if that is the case. It is by no means universally the case.

 

[woodbrains]

Hello,

I might have been misleading; I mean I never had to use any dodgy methods to compensate for blade drift, setting the blade's teeth off the front of the tyres induced no drift. Flat tyres work!

Mike.

 

[Steve Maskery]

I see. Well in that case you are a very lucky bloke, because most of us do not have that good fortune.
I'm not knocking it, not at all.

 

[david123]

Read and digested all you advice.
The wood is dry, I bought it as an offcut from Beech Brothers timber merchant in Exeter, but I take you point, I may be putting to mich pressure inputting the oak to the blade.
Yes Steve,I have got your superb vidio on setting up a bandsaw and will try and lock it for a second visit (stuff is still hiding away from oir move to Devon.