Where am i going wrong with bandsaw?

[dvddvd]

I wanted to cut some thin pieces/ veneers from some hardwood.
The pieces of timber I have are 150mm high.
I've watched a lot of videos on YouTube and followers there tips.

I bought a Record sabre 450, their biggest model.
I bought a new blade from tuffsaws that the recommended for veneer cutting.
I also bought the Bow bandsaw feather board which is made for cutting veneers.

I set the blade up, it's at maximum tension. I squared the fence and table and set all the blade guides.

I followed all the guides on YouTube and did what they recommended but it still won't cut a perfect veneer.

Sometimes you think you have nailed it and the top looks fine and then realise that the bottom is 2 mm thicker etc.
I don't know what else I can do?
I can get an ok one on a piece of material which is 50mm high, but any higher and its bad news.

As I said the blade is new and it feels fine but it is tensioned to the max, could the blade be a little to long?

 

[Orraloon]

When you say max tension you need to be aware that the gauge is only a very rough guide. If you can still krank it up some more then do so. My early attempts at resawing were a disaster because a recommended blade I bought was too wide for the saw to tension properly. The specs the makers publish can be a bit optimistic sometimes. Max tension is when the spring is fully compressed and its not recommended going that far. If you are at that stage perhaps a narrower blade could be the answer. Now assuming the setup is right the fence is sturdy and high enough then the rest is technique.
bandsawing vineer - Google Search
Regards
John

 

[pgrbff]

Setting up a bandsaw can be a bit tricky. I changed the blade on my Hammer N2-35 yesterday, from a 3/8 to a 5/8 to resaw some ash and it took a lot of fiddling to get the cut right.

 

[MarkAW]

Stock even thickness to start?
Not feeding it too hard?

 

[Gary B]

Given that everything is square and the guides have been checked (including beneath the table?) I would try cutting some without the Bow featherboard. I have one and I am not convinced it has sufficient pressure to keep the wood flat against the fence. Now I just use a grippy pushblock and really drive the piece into the fence just before the blade to make sure it is flat against it, particularly the bottom half of the piece which I found has a tendency to want to come away from the fence if not held in firmly. And go slow also.

 

[dvddvd]

Thanks, it won't let me tighten it anymore, but not sure if it's tensioned enough? Seems to work if I drop the adjustable guides so only 50mm of blade is showing but put them up so 100mm of blade is showing and it starts to drift

 

[Agent_zed]

Does your blade guard move the blade as it moves up and down? They can be adjusted so they follow the blade line. If they are out then when you tighten it it can force the blade out of line.

Try putting the blade guard in different positions and tighten it up and see if it moves the blade

 

[Richard_C]

I squared the fence and table

Squared table - which bit to what thing? It sounds like the veneer thickness varies from top to bottom of your cut. Have you checked that the blade is running at exactly* 90 deg to the table top? I don't know that model, but most bandsaws have a tiltable base and most have a stop screw so it goes back to horizontal when you clamp it back flat. That stop screw is adjustable, and even a bit of dust/dirt in the way can stop the table being properly and reliably flat. Easy to check with a square against the side of the blade and the top of the table.

* Its a long time since I did any trigonometry so I could be wrong, but I calculate that a 1 degree error in the angle between blade and table translates to 2.6mm error in veneer thickness over a 150mm deep cut.

 

[Spectric]

My early attempts at resawing were a disaster because a recommended blade I bought was too wide for the saw to tension properly.

You have not said what width of blade you are using ? I can say that on the BS400 which is supposed to be able to use a 1 inch blade that it cannot tension it properly and a 3/4 is really the max.

 

[Deadeye]

Do a test like this:
Take a properly square board of decent thickness, and just nudge it along the fence onto the running blade. Don't try to cut far, just enough to scratch down the wood.
Is the line parallel? If not, then the blade is not parallel to the fence/square to the table.
If the line is parallel, nudge the wood a bit deeper, very very slowly, I mean painfully slowly. After a couple of cm, back out and look at the underside - is the cut straight or veering?
If the cut is straight, then your issue is about feedrate and technique.
If the cut veers my hunch would be tension.

 

[Orraloon]

Thanks, it won't let me tighten it anymore, but not sure if it's tensioned enough? Seems to work if I drop the adjustable guides so only 50mm of blade is showing but put them up so 100mm of blade is showing and it starts to drift

For any cut the top guides should be just high enough that the wood can pass under. Should be hardly any blade showing above the wood. A basic rule of bandsawing.
Regards
John

 

[dvddvd]

For any cut the top guides should be just high enough that the wood can pass under. Should be hardly any blade showing above the wood. A basic rule of bandsawing.
Regards
John

Thanks yes I've adjusted the guides to their lowest point with reference to the piece of wood so that no blade is showing above.

 

[dvddvd]

You have not said what width of blade you are using ? I can say that on the BS400 which is supposed to be able to use a 1 inch blade that it cannot tension it properly and a 3/4 is really the max.

I will check, but I'm sure it was a 3/4 blade...when I tension it I go as far as it will go. But then with 150mm of the blade showing I can deflect it with one finger to the side

 

[Terry - Somerset]

On my bandsaw the top guides are easily accessible and visible - easy to set accurately with the rear guide in the right position and sides close to, but not touching the blade.

The bottom guides are fairly inaccessible hidden below the table and awkward to adjust accurately - I often use a small mirror to help rather than remove the table.

If the lower guides are not properly set and aligned with the top guides, it is entirely possible the blade will appear correctly set at 90 degrees to the table when stationary, but deflect when under load and rotating.

It may be that you machine is a rather higher spec than mine without these sort of issues - but worth thinking about.

 

[deema]

There are only three things basically to cause the blade to wander. First is the gullets are not large enough to take the sawdust and get chocked pushing the blade aside.
Second is a damaged or blunt blade. Can be caused by the blade guides touching the teeth and affecting the kerf on one side of the blade.
Third is insufficient blade tension. The spring may be over compressed…, in fact from your description sounds that it could be. If a compression spring is compressed by more that 25% of its length, it’s toast. So, coil on coil compression is a buggered spring. Most bandsaws don’t have bump stops to prevent over compression.

Have a read of this on blade guides to dispel a few myths.
https://www.ukworkshop.co.uk/threads/bandsaw-blade-guide-theory.135481/

 

[JSW]

I will check, but I'm sure it was a 3/4 blade...when I tension it I go as far as it will go. But then with 150mm of the blade showing I can deflect it with one finger to the side

I'll play Captain Obvious here and ask if the blade is the right length, just to remove all doubt.

Link us to the blade you bought?