Which cutting band really is best

[kkcomp]

I have seen many people, including myself, ask about band (blade) life. The question always seems to stem from an economic and value standpoint. The typical response is some for of I use Brand X or Y because based on that person's particular reasoning and situation which may be drastically different from the next person to respond. Put simply, the person running a multiple million-dollar hardwood business has different requirements, expectations and criteria for determining economic and value than a person cutting to put up utility sheds on their homestead. As well as does everyone in between. There are also other factors such as brand loyalty (think Ford vs Chevy arguments), predominate climate and even the sawyer themselves. I have also seen many make statements like I normally get so many BDFT per band before I change out. This is also ambiguous because it could leave out important factors such as are you cutting 4/4 or 8/4 or dimensional 4X4 etc. After all the question really is about amount of cutting and not directly about the amount of boards produced. There are also other factors such as what are you cutting, WP being less dense and less hard than WO

From the collective experience there seems to be a DeFacto rule to change a band when it is not sharp. Also, that not sharp is different than dull. My limited time milling has shown me that is something that can only be determined through experience. However, many experienced people have been quite helpful in sharing the signs to look and listen for to determine that.
This still leaves the original question asked in some form or another of which brand is best or is there really any difference? 

To address such issues, I propose and would like to see some sort of an industry standard expectation rating be created. This is what I have thought up. I call it the cut foot which is one foot of cut depth into one foot of width. Then a secondary rating based on Janka hardness. I only made four hardness groups because quite frankly I do not have enough experience or access to different tree species to know if a Janka 2000 is twice as hard to cut as a Janka 1000 so more groups may be appropriate. Therefore, I based my groups on the fact that Janka is a linier scale.
 
One Cut Foot² = 12 inches of 12-inch-wide cut
Groups:
A-      Janka below 1000
B-      Janka 1000-2000
C-      Janka 2000-3000
D-      Janka above 3000
 
So hypothetical brand X Silver blades have an average expectation of 1000 CF²A, 650 CF²B, 250 CF²C

And hypothetical brand X Blue blades have an average expectation of 1200 CF²A,750 CF²B,450 CF²C


Any thoughts? Suggestions? Or even comments of I have way too much time on my hands.
 
 

[KenMac]

I'll jump in here with my perspective. I bought a Cook's mill in 2019 and have used the blades they recommended at that time with no issues. If you're not satisfied with what you've been using, then you may have to buy and try others until you find the one-or ones- that work for you in your circumstances. I know that's not very scientific but I chose not to chase blades hoping to find a better one, but probably never succeeding. Good luck!

[Magicman]

Yes.

[Ljohnsaw]

I raised that very question/hypothesis early on in my sawing journey 12 or so years ago. Blade life is based on area cut, not volume. Since the width of the cut has some bearing on speed of a cut through a cant, as well as hardness, perhaps a reasonable proxy would be hours cutting.

It would be a matter of teeth in contact with the wood that causes dulling. Harder wood you cut slower, more band revolutions, more contact per linear foot cut. Likewise for width.

That, at least, would work for lower HP setups.

Maybe hours cutting with adjustments for wood hardness and HP?

[SawyerTed]

There's something to this line of thinking.  Admittedly it's beyond my capacity to wrap my mind around it.  The variables ... the variables?

Each log would have to be measured for hardness?  Wouldn't that be necessary to compare blade life relative to wood hardness but not necessarily species?

X amount of board feet cut in Y hardness material regardless of species?  

[trapper]

Also amount of dirt in the bark for us without a debarker

[Ianab]

I think there would be just too many variables to take into consideration? Janka hardness is only one measure of wood properties, and of course it does matter, harder woods are generally more difficult to saw, and it's common to select different tooth angles for different wood types as they can give much better results. But other things affect the equation too. Size of logs, larger logs have more teeth in the wood, so the power needed to drive the band properly is going to change. Sawmill power? Related to log size issue, do you have 55 hp or 15 hp? That's going to affect which band works best for you as well. Then there is "fuzzy" or pitch loaded woods, that probably affects the tooth set, and "problem" woods like knotty spruce, which is pretty soft on the Janka scale, but has hard angled knots that cause blade deflections. Other woods are known for dulling bands quicker, in spite of not being super hard. Harder steel or carbide bands for those?

One thing that's murder on band life is having to slow down in the cut, through lack of engine power. Each time the band passes through the wood, the teeth have to slice through all the strands of wood fiber, no matter how large of a bite they are taking, and the wear on the blade tip is similar, even if it's only taking 1/2 the bite. So a low power mill will usually get less production out of each band, compared to a higher powered one that's throwing out coarser sawdust. 

Band wheel size vs band thickness is another issue. The smaller the wheels the more the band has to flex each time around, until it eventually breaks. Thicker bands can handle more pressure / power and cut faster (if you have a high powered mill), but on a small mill they may break prematurely.

So while the "best band" idea has merit, it's the best band, for Your mill, and Your logs. Wood hardness does come into the equation, but it's not the only factor. And there is also the "keep is simple" principle, where you don't want to be swapping between 4 different bands depending on what log comes up next. Pick a "general purpose" one that cuts most things "OK", and just use that. 

[WV Sawmiller]

  When I bought my mill (25 hp gas engine) I bought a selection of 4,7 & 10 degree hook angle blades and later tried some turbo 7's and over the years have standardized on the 4 degree hook angle. (I probably did not give the turbos a fair chance but life is hard and they will just have to get over it).

   I found the 4's worked best in my hardwoods and when I cut soft woods like tulip poplar, spruce, or white pine they still had t6he occasional very hard knot that would cause the deflections Ian talks about above.

    My suggestion is to try an assortment of blades and hook angles, give them a fair test and settle on the blade(s) that work best for what you are sawing and that your mill can handle best. Good luck, let us know how it turns out and lessons learned in the process.

[Nebraska]

I'd read and enjoy the findings.  I'm sure it would be more interesting to me than most all of network tv.     

[thecfarm]

I like a NH tractor better. 

[barbender]

I don't think all of the carbon steel band blades on the market have a hill of beans of difference between them as far as alloy composition. I have no way of verifying that, other than personal experience- they all seem to have the same sharp life to me. 

The difference between manufacturers for me has been consistency in tooth spacing, set, and weld alignment. 

The real differences seem to exist mostly in the marketing departments.

[ladylake]

 
Like above I've tried bands from quite a few different companies, no matter how much hype some got they all cut about the same . Steve

[DDW_OR]

https://forestryforum.com/board/index.php?topic=124930.msg2041659#msg2041659

good info here

[kkcomp]

I don't think all of the carbon steel band blades on the market have a hill of beans of difference between them as far as alloy composition. I have no way of verifying that, other than personal experience- they all seem to have the same sharp life to me.

The difference between manufacturers for me has been consistency in tooth spacing, set, and weld alignment.

The real differences seem to exist mostly in the marketing departments.

And this is exactly why I suggest some sort of standard. It will always come down to preference I.E. Ford vs. Chevy but it would make the manufacturers back up the claims.

[Peter Drouin]

I use WM, I get them all from Ross WM of Maine. 
They are best after I sharpen them and push out the set.

[barbender]

Kkcomp, it would be nice if you could find specs for Rockwell hardness of the teeth and band body for sure. The specific alloy composition I would expect to be proprietary (or at least claimed to be) so no one is likely to give that up.

It would be interesting to know how many steel mills are actually producing raw band blade coil stock. I wouldn't be surprised to find there are only a handful of sources. 

[jpassardi]

I'd say you're spot on BB, they're are likely only a few manufacturers of the coil.

[Machinebuilder]

AS far as the MFg of the steel

 will be pretty far off on the numbers.

When I was working for a mfg of rack and pinion steering gears, we had a metalurgist working with a major steel supplier.

We used a 1040M steel for the rack bars and produced 5-10Million gears per year.

One crucible of molten steel was more than 10 times the amount of steel we purchased in one year.

I would be pretty sure that all of the band mfg's use less steel per year.

until you get into the bimetal and carbide blades I will guess the steel id a fairly standard alloy, and the differences are in the tooth profiles and processing.