Thread: bandsawn vs chainsaw slabbed

Like most things it depends on on a lot of variables.

If you could afford a bandsaw mill and were mill mostly logs from European and American species then from what I've read BSM beats CSM hands down. Its when you start into Australian hardwoods that it appears that the debate is ongoing. At least for the hobbyist or small professional anyway.

Thanks Weaver, I should explain my position in the debate (at the moment). I can see that the bandsaw will save kerf wastage, but it is the amount that I am unsure of. The fella I am arguing with states that for every 5 x 50mm slabs with a chainsaw mill, you would get 6 bandsawing. From what I have seen, using 3/8th chain and cutter angles of 10-15 degrees, it would be more like for every 9 slabs with a chainsaw you would get 10 bandsawing. If bandsaw blade wander is a significant factor in wide slabs of hardwood, then there would be even less difference. I realise operator skill and machine quality/setup would be a huge factor in practice, but I want to remove this from the debate at this point, and assume all this side of things is equal and optimum.

The fella I am arguing with states that for every 5 x 50mm slabs with a chainsaw mill, you would get 6 bandsawing. From what I have seen, using 3/8th chain and cutter angles of 10-15 degrees, it would be more like for every 9 slabs with a chainsaw you would get 10 bandsawing.

Using your numbers it's even more than than you think.
To get an extra 50 mm board the "kerf losses difference" have to add up to 50 mm.

Assuming the 3/8 chain has a 7 mm kerf and the BS has a 3 mm kerf the kerf loss difference is 4 mm, 50/4 = 12.5, so 13 x 50 mm boards have to be cut to get one more.

3 mm is a thick bandsaw kerf but may not be unreasonable if blade wander is considered. If the blade it tracking true and the BS has a 1 mm kerf the sum becomes 50/6 = 8.3 or 9 boards

For a 404 chain where the kerf loss difference is 7 mm, 50/7 = 7.14, so 8 boards have to be cut to get one more. For a 1 mm BS blade its 50/9 = 5.55 or 6 boards.

Whatever the case CS milling generates a lot of saw dust. If you slab a 1 m wide by 3 m long log with a CS mill into 50 mm slabs you generate ~130 kg of sawdust!

Don't know about a lot of experience, but i will share some of my exposure to the bandsaw.
I had a fairly large cedar tree a while back and slabbed most of the billets to 50mm.
Thinking i was doing the right thing and saving on some wastage, i took the last billet to a "mate" who had a portable bandsaw. My intentions were to cut a heap of 1 inch slabs from the billet for future panel work etc.
After the first couple of slabs looked like Bondi beach due to the wandering blade and 3 or 4 blade changes during the logs demise (which i agreed to pay for the resharpening as part of the bill) i got the slabs but frustrating all day and cost a fortune.
Thought about it all the way home and once arriving home, patted the Lucas as i walked past it to the beer fridge.
I'll stick to the Lucas and of course----- ditto to what Burnsy thinks of these great pieces of gear.

Originally Posted by rosewood

Thought about it all the way home and once arriving home, patted the Lucas as i walked past it to the beer fridge.
I'll stick to the Lucas and of course----- ditto to what Burnsy thinks of these great pieces of gear.

I love my Lucas but it is Allan (Sigidi) who LOOOVES his Lucas.

I reckon Nifty could enlighten us on the bandsaw topic seeing he owns a Woodmizer. How about some pictures of it in action Nev?

Like a lot of tools its the nut behind the controls that has a lot to do with how effective it can be used. I have seen a heap of pictures of very straight narrow kerf boards displayed on the ArboristeSite. I have asked a couple of the Bandsaw millers for permission to post their pics here to demonstrate what can be done.

I heard Lucas and my name mentioned... what?.. hey???

Yeah look, I've on occasion had a debate similar to how many can you get when comparing the two.

I've no experience with wide band slabbing, so for 'real kerf' figures we'll have to get them from the guys that do it, but for chainsaw slabbing like Bob said about 7mm kerf with .404 chain and less than 1mm lost to removing the chain marks (take a look at the "ammamoor Slabs" thread for proof) so 8mm total kerf.

If the bandsaw has a kerf of 1mm on the band what does that equate to actual kerf in the timber and does it need a similar amount to remove saw marks (around 1mm for my slabber)

So I put the figure at around 9 slabs needed on a bandsaw slabber before gaining 1 slab over doing the same log with my lucas slabber. Having said this after talking to a fella who cleans and dresses slabs he advised me if I was bringing more slabs to him to cut them at 65mm not 50mm as he felt over the face of most slabs it doesn't take very much to require a heap to be taken off before you get 'clean board and then you are left with a 38mm slab more often than not. So using 65mm (although you didn't ask for it) it would mean 11 slabs on a bandsaw before it could gain 1 over a chainsaw.

The worst thing I reckon is a heck of a lot depends on the operator, I've seen (and cut a very small amount) slabs with 6-8mm washboard from the chain across the face obviously bringing the number down closer to 5 slabs before gaining 1.

If your bandsaw operator pushes their band too far before replacing or sharpening, then I'd expect you'd get similar losses.

So it's easy to say lets forget about everything else and just do a direct comparison, but it just doesn't work that way.

Looking forward to hearing about the bandsaw side of things.










Oh and yeah - I love my Lucas!!!

They're all ducking for cover.....

The video of the woodmizer I have seen looks pretty impressive and a lot quicker than a chainsaw/lucas slabber so really you would have to take the cost of cutting the slabs into account as well.

I doubt that the likes of woodmizer would be able to sell their product here if it was not capable of cutting quality flat slabs so as Bob says, maybe the operator.

I have to admit Mike, the nature of band mills is why I bought a circular. Before buying my mill I was on an American Forum way too much, me would you believe it?!?!

Anyway, I figured out way beck then, a band mill needs a lot of experience behind the operator before good timber comes out - I didn't have that much time as a luxury - I wanted to cut our own timber pretty darn quick and also start turning over some $'s too and it worked

Can't wait to see what the band milling boys have to say.

If I compare my vertical bandsaw with my chainsaw and asuming that both r running perfectly...sharp cutters/teeth, tuned,etc etc bandsaw easily produces a narrower kerf in the order of 1 to 2mm compared with 7 to 8mm as others have said.

If however the blade on the BS goes off it will wander offline follow the grain, cut thick or thin depending which side the teeth have lost sharpness or set.
Not good if u r trying to cut good straight 1" thick boards much like Rosewood said.
Wider blades improve this wander tendency.

If I compare surface finish in "general" bandsaw wins especially if I use the tungsten tip blade, the finish can be good enough to go straight to a sanding machine (not green wood tho) Chainsaw will produce smooth flat timber as I and others have done but everything has to be right there as well...mostly anyway, sometimes u can get away with some dodgy bit of chain and still produce good timber like Allan showed us with his Ammamoor slabs nice bit of stuff there btw

In theory bandsaw will produce more timber by virtue of the narrower kerf, in practice tho many things go wrong and they can leave u scratching your head
Is one better than the other? It depends.

Just my 2 cents...

Peter.

I can see a lot of this is coming down to what actual kerf there is on a large horizontal bandsaw, and then what the blade wander adds to this. BobL, you stated that 3mm is a wide kerf for a bandsaw but reasonable to assume if it includes wander. I was under the belief that kerf loss is 3mm alone, and wander may add 1 or 2 more to this. Even my vertical bandsaw has a kerf of 2.5mm when I run the 30mm blade.
The other thing that occurs to me is that as the chainsaw cutters dull while milling the kerf doesn't increase, it just cuts slower, whereas on a bandsaw the wander, and hence kerf, presumably increases as the blade dulls. This no doubt is a big factor in practice.

I used to have a Portamill bandsaw.
Blade wander was a real pain. After 2 or 3 slabs of messmate,which isn't very hard, the band would start to wander. I used to work on an average of 4mm wander per cut.

So in 1 day I might need to change bands 4 or 5 times.
The downtime in changing bands is as important as kerf loss.

The situation is different for the wide band high tension bandsaw mills but they are in a totally different price range.

By the time you anaylse wastage and the necessary time lost resawing on a bandmill just to straighten wavy timber a chainsaw mill seems a superior choice to me.

Originally Posted by timbertalk

I can see a lot of this is coming down to what actual kerf there is on a large horizontal bandsaw, and then what the blade wander adds to this. BobL, you stated that 3mm is a wide kerf for a bandsaw but reasonable to assume if it includes wander.

Apparently not if you know what you are doing.
I have obtained permission to post these pics from expert Band Miller, Sawyer Rob on the Arboristsite.




Now there may well be differences with some of our aussie hardwoods but including wander that does not look like like more than about 1 mm to me.

And just to stir the pot he also sent me this one of of "swing millers can do no wrong"!


He said he might pop over and sign up - be good if he did as he knows heaps about BS milling

Like I said, . . . . "- it's the nut behind the wheel".