What does steam mean?

[YellowHammer]

So you are sharpening the bands but not setting?

[Digger Don]

Guilty as charged. Let's just say I'm trying to sharpen. That may be part of the problem!   Or, the whole problem. I'm amazed at how fast you saw in the video. Can you go that fast in an oak log?

[customsawyer]

A 10X magnifier is your friend when you first start sharpening. Make sure you are getting a good grind all the way to the corners. Especially on your set teeth.

[Digger Don]

You mean my bifocals aren't good enough?!    I can get the magnifier, but I'm not sure I'll know what good looks like, if I see it.

[SawyerTed]

You need one of these to check set. 

[YellowHammer]

Yes, red oak saws very fast and easy, I smile everytime I put one on the mill.  Proper set is crucial to band performance.  What kind of setter are you using?  I bet there are lots of folks on here who may have it and maybe help you out get it dialed in.   

I had a couple guys drive from several states away to Alabama a couple weeks ago who had their own lumber and sawmill business and wanted to talk about mine and the subject of speed came up.  They had an LT70, just like mine, maybe newer.  Anyway, I had just sawn some boards and I pointed to the teeth marks and showed that that I was moving about 4 inches per band rotation.  They were shocked, they looked at each other and said they maybe got one inch of advance per band rev, sawing small diameter logs in soft softwood, such as cherry and walnut.  I mentioned they should be pushing easy 3 to 4 inches per rev in those!

By the way, looking at advance per rev is a very good way to "grade" and evaluate both my bands, my mill, and me.  I discuss it in several videos, but you also know when you are sawing dead on when you hear the very clear sound of the band, I have been told it is an E flat, and once heard is never forgotten.  It only happens when the band is right, sawing fast and flat.  It's music that I always try to push the mill to generate.

On another note, (pun intended) last year at Jakes Project, Customsawyer, I had a couple guys come up as he was sawing and they were asking about the note of the band I keep talking about in my videos.  I said watch Jake a second and you will hear him hone in on it, and sure enough, the very next cut in that 40 foot long cypress, he hit and maintained "tune" for most of the cut, and the sound was ringing clear as a bell from 30 feet away, and one of the guys exclaimed "I HEAR IT!"   

[moodnacreek]

I guess it is a mini, then.

At first, I didn't appreciate your comment. Then, I realized my 8,000 LB. excavator is considered a mini. I wasn't aware of how big a band mill could be. So, no offense taken. Thanks to all for your comments. Don

I think there are band saws 12" wide and even larger and with teeth on both edges [double cutters]. My excavator is 4000 lbs. and very handy.  There are members here with 'swing' sawmills that use small circle saws. Some of the Amish mills have carriage mills [like circle mills have] with a 2 " to 4" fixed vertical bandsaw.  Doug

[Digger Don]

Red oak saws fast and easy?! Boy, we are definitely doing something wrong! We were sawing it today and going about as slow as possible. I doubt that we were getting one inch per rotation. If we went any faster, it drug the engine way down. I suspect the fact that the cant was 16 X 18 may have had something to do with that. It was leaving a LOT of sawdust on the boards, too. At one point, I checked the blade after it came out of a big cut. It was a little warm to the touch, but not hot. 

I'm not certain what the setter is, but I think it's something from Timberking. It came with the mill when we bought it. I'm not sure if it does three teeth at a time, or just two. We messed with it once or twice and gave up. I think it's time we take the time to figure it out.

I love the videos, but I have a pretty low data limit, so I can't watch nearly as many as I'd like. I'm hoping we get better internet in the next year, or so.

Pardon my ignorance, again, but if our mini can cut a 2 1/2 foot log, what size can a 12" band cut? I would think trees of that size are pretty rare. Or, do they just cut the log a LOT faster?

I suspect the note is something that if I ever heard it, I didn't know what it meant. I certainly wouldn't know an E flat if you hit me with it. Don 

[beenthere]

Google "play an E flat" and you will hear it. 

 
E flat sound

[Machinebuilder]

Digger Dan 

AS far as the speed that Yellowhammer saws at, remember he has a 55hp diesel engine.

He will be able to saw much faster than you can or I can with my 19hp gas engine.

I agree red oak is fairly easy to saw. Because I tend to have pretty big logs I can not saw fast enough to clear the sawdust.

I have learned that if I add a glug of dawn to the water tank and keep the drip very slow it helps and I can mostly dump the sawdust off as I remove the board.

I try to control my cutting speed to keep the engine RPM above 3300RPM, I adjusted things so the engine is always WOT when engaged.

I enjoy watching different sawmilling videos and have learned much from many of them. I just have to also realize there are some techniques that don't apply well to a fully manual hobby mill.
For example I don't try to use the reverse roll quarter saw because its too much effort for me with a cant hook and manual clamps.

I was just thinking about chip load, IE how mach each tooth is removeing, at 4" per rev the chip is 4x bigger than at 1" per rev.
This is where YH talks about corn meal consistancy sawdust where mostly I see flour consistancy.
It also will take 4x the power to make the cut. (disclaimer very rough estimate)

[Magicman]

I have a 38hp Diesel.  I saw as fast as the engine can handle without reducing the speed and it does not approach YellowHammer's sawing speed.  Maybe half but honestly I know that the engine is doing all that it can do so I seldom look.  I know for certain that my sawing speed reduced when I had to go back to a non-turbo engine in November. 

[Digger Don]

It makes a lot of sense that the bigger engine will cut faster. We have a 25HP Kohler, which I'd say is less than half of what YH has. We keep it at WOT when sawing and try to maintain at least 3,300 RPMs, too. Is there a rule of thumb concerning how much the engine should be allowed to slow? I'm thinking about 10%, but that is just my uneducated guess.

We used to used water and liquid soap, but have changed to using diesel. It seems to keep the blade cleaner and doesn't freeze like water.

We've never tried to quarter saw anything. Whatever comes out quarter sawn from our regular sawing is what we get.

MM - I don't remember the actual number you mentioned as to what you can saw in an hour. But, I do recall being amazed by it. When I'm by myself, I'm happy if I can get 150 bd. ft. That rarely happens. The turbo diesel might be a big part of that.

[terrifictimbersllc]

Yes, red oak saws very fast and easy, I smile everytime I put one on the mill.  Proper set is crucial to band performance.  What kind of setter are you using?  I bet there are lots of folks on here who may have it and maybe help you out get it dialed in.   

I had a couple guys drive from several states away to Alabama a couple weeks ago who had their own lumber and sawmill business and wanted to talk about mine and the subject of speed came up.  They had an LT70, just like mine, maybe newer.  Anyway, I had just sawn some boards and I pointed to the teeth marks and showed that that I was moving about 4 inches per band rotation.  They were shocked, they looked at each other and said they maybe got one inch of advance per band rev, sawing small diameter logs in soft softwood, such as cherry and walnut.  I mentioned they should be pushing easy 3 to 4 inches per rev in those!

By the way, looking at advance per rev is a very good way to "grade" and evaluate both my bands, my mill, and me.  I discuss it in several videos, but you also know when you are sawing dead on when you hear the very clear sound of the band, I have been told it is an E flat, and once heard is never forgotten.  It only happens when the band is right, sawing fast and flat.  It's music that I always try to push the mill to generate.

On another note, (pun intended) last year at Jakes Project, Customsawyer, I had a couple guys come up as he was sawing and they were asking about the note of the band I keep talking about in my videos.  I said watch Jake a second and you will hear him hone in on it, and sure enough, the very next cut in that 40 foot long cypress, he hit and maintained "tune" for most of the cut, and the sound was ringing clear as a bell from 30 feet away, and one of the guys exclaimed "I HEAR IT!" 

Got a pic of the cant on what that 4" per rev looks like? 

[GAB]

Question and comment:
Mr. Milton I believe that you have a wide head saw.  How long is your blade?  A ratio of one's blade length versus his times 4" would be what your equivalent to his 4" would be in my estimation.  That is if I'm not all wet as I have been known to be in err more than once.

A few year back at Bruno's I was sawing with another FF member's LT40 with the Kohler engine and I learned real quick that I could not go as fast with it as I can with my LT40HDD34.  That gas engine just did not have the torque that my diesel has.
GAB

[Machinebuilder]

I think the answer for what RPM is Just above the torque peak of the engine.

That way when it starts to slow down the torque will increase and the RP will not drop as much

[Magicman]

MM - I don't remember the actual number you mentioned as to what you can saw in an hour. But, I do recall being amazed by it. When I'm by myself, I'm happy if I can get 150 bd. ft. That rarely happens. The turbo diesel might be a big part of that.

I have no idea because productivity is not one of my goals.  My only goal is to saw quality lumber for my customers and meet their cut lists. 

[Digger Don]

I think the answer for what RPM is Just above the torque peak of the engine.

That way when it starts to slow down the torque will increase and the RP will not drop as much

I don't know what RPM that would be. But, the engine on the mill is very similar to the engine on my track loader. The torque peak on it is 2,400. At 3,300 RPM, it's just under 38 FT-LBS. At 2,400 RPM, it's just under 40 FT-LBS. Is the two extra FT-LBS worth letting the blade slow that much?  

[doc henderson]

you want to get their and not go under.  that is getting all the power out of that engine.  most have a graph you can look up.

[Digger Don]

I understand that 2,400 is the torque peak, but won't that slow the blade too much? I'm thinking (right or wrong, I don't know) that keeping the blade speed up would be more important than those last two FT-LBS.

[doc henderson]

there is a relationship between RPMs and HP, and HP and torque.  look at graphs all you want, but you may just have to push when all things are right to see the limit.  I did that.  I will occ. push with a dull blade and that does not work.  you have you watch the sawdust and listen to the blade and motor.  push a little at a time and see how it goes.  If rpms drop a bit and torque goes up, it should keep things form going slower.  keep pushing and rpm and torque drops and you are done.

[Ben Cut-wright]

Question and comment:
Mr. Milton I believe that you have a wide head saw.  How long is your blade?  A ratio of one's blade length versus his times 4" would be what your equivalent to his 4" would be in my estimation.  That is if I'm not all wet as I have been known to be in err more than once.

Correct, the surface speeds of both lengths is the same but the length traveled is farther. 

[Ben Cut-wright]

I understand that 2,400 is the torque peak, but won't that slow the blade too much? I'm thinking (right or wrong, I don't know) that keeping the blade speed up would be more important than those last two FT-LBS.

Your question is often asked and (I think) you are correct in your thinking.  RPM (and) torque results in HP.  In other words, horsepower is work done over time. I find NO information instructing operation of the band saw mill in the "peak torque" range.  What I have repeatedly found is a specification for "surface speed".  3,000 to 3,600 is normal max RPM for these small gas engines. If the engine RPM is reduced to a peak torque of 2.400 RPM's  blade *speed will be significantly reduced. 


Saw blades running out of the cut don't require max governor operation.  I adjust travel until the governor has the throttle at wide open *during cutting but RPM's only drop slightly. There are other factors/indicators one must take into consideration but governor throttle control is a major one for me.  A tachometer can monitor when the governor has the throttle at max.  Eventually most sawyers can 'hear' and feel correct load on the engine. 

[Digger Don]

Doc, Our problem is that we haven't been around well running mills enough to know what that sounds like. So, until that time comes, I'm going to keep it WOT and the RPMS, while sawing, no lower than 10% below the unloaded speed. That's around 3,400.

Ben, we do have a tach so keeping the speed up isn't too hard. One thing I wish our mill had was a different throttle control. It runs wide open, or wherever we set it, whether it's cutting or not. No slowing between cuts. 

[doc henderson]

DD, my 2000 has a dc solenoid on the throttle.  It has a momentary on off on switch to reverse polarity for the dc part.  up and down throttle.

[YellowHammer]

Most of my videos will show me cutting in the 3" to 4" advance range, unless the log gets big or hard, then I have to slow down.  Here are a couple photos I took today, between 3 and 4 inches of advance per band rev on some wood I had sawn previously.  I have the LT70 wide, 55 hp diesel and have a few teeth out on the band I was sawing the red oak, which has since been kiln dried and hit or miss planed.  Ugly band but good for showing advance using poorly set teeth.   

Red oak, 3.125" of band advance per rev.
Red oak, about 3.5" band advance per rev

Pic 3 is really cool, a detailed close up tells a good story's and shows how much I change advance during the cut, and also why faster is better.  This cut was with a good band, very few offset teeth.

There is a tooth mark about an inch in front of the tip of the tape measure, where I slowed down for the ugly knot, so I had decreased to 1 inch per rev, then at the tip of the tape, I was about through the knot, so started accelerating my feed, and on  the very next cycle, was up to what looks like almost 1.75" advance per rev, which means I was starting to increase feed rate quickly.  Then after that, I put the hammer down, and really increased feed speed and the teeth marks pretty much disappeared, or at least shallowed out where I can't discern them anymore.  I would guess with my eye I was thinking it was back to to over 3" per advance, but I can't pick it up in the photo.  However, the cool thing is that it shows as advance increases, the cut quality also goes up.

Pic 4 is one I have on my latest video, and shows how little sawdust I have left on my boards, virtually sawdust free.  With the teeth on this band, I can't tell what the advance it, but its pretty fast.

I think the key on all this is that it doesn't matter quantitatively how fast you saw, it matters that you are sawing as fast as possible, balancing the band performance, the hp of the mill, the species, all that stuff plus more to get flat cuts and nearly sawdust free boards.

By the way, when sawing fast, there reaches a point where you can actually hear the advance is faster than the band can cut, especially in smaller cants and logs.  The cut isn't lugging the mill, but you can hear and even feel that the band has reached cutting capacity, the sound changes to a dull sound, and the feel of the mill gets "hard" for lack a more descriptive term.  I call it "stuffing the band" although there may be another name for it, it just can't eat faster, like the gullet is full and literally can't carry anymore.  It's a very distinctive feel and sound.

Anyway, you guys may think I'm off base, but I just call it the way I see it.  Also, there are guys on the Forum who can cut a board in a higher gear than I can, I've seen it.