Thread: Log Tension by Timboz

Originally Posted by rustynail

John, I agree, there are always logs that are non viable. My concern was that a lot of what I saw over the years was quite millable, provided the miller had the skill. This was also Don's experience, hence his comment to me about checking the log dump. Many parts of Australia are still well forested, while others are now scratching to come up with a millable log. The importance of not wasting a resource is far more relavent to the later than the former. Nonetheless, all parties need to make the best use of a given resource.
If the determining factor is the skill of the miller, then should not the mill have the necessary skill? Im not talking about bad logs. There are always those. Im talking about mill skill. That to me is very different. When you see logs sitting in the yard for the want of someone who has the ability to turn it into stick is sad. Particularly when
some of those logs are exotics.
As for cooking the pig? Yes, we could do that.....once. Then there is no more pig. Instead, we have an abundance of silk purses. A matter of priorities I guess.

Mate, please don't get me wrong here. I agree and wholeheartedly endorse everything you've said. I say the same things often enough myself.
My point is that regardless of the skill of the miller, the technology he has at hand will play a large part in what logs it's economically viable to mill.

Lets say you've got an order in for 50 lengths of 150 x 50 GOS at 5.7 long. It's not a bad little order by anyones standards, 3 grands worth give or take a little, not too small for a bigger mill to take but not too big for a little guy either. The order is for "straight" timber.... average stuff, not gunbarrels but we can't ride the deflection table of AS2082. The kind of stuff the customer expects to buy off a professional operation, and all our millers are professionals.
The logs at hand are some nice clean little Forest Red Gums... and I've picked that species specifically because it's a timber most eastern seaboard millers are familiar with, and it's known to move a little when it's small. Logs are clean, reasonably straight, and would be good except that they average around 18 inches diameter, with the largest being 600 and the smallest 300. They're going to pull.

Sawmiller A has a Lucas Mill. By facecutting on each "deck" of boards he'll get some off no problem at all, but is going to be forced to oversize and straighten on a lot of them because of the spring. Doing that with a Lucas is bloody hard work as anyone's who's done it knows, and it's actually going to take him longer to resaw then it will to do the initial breakdown. He's going to loose a few when he resaws too - the hardest part of doing that operation on a Lucas is actually holding the board in place against the log. And FRG is hard enough that he can't stack multiple boards on top of each other because they'll tend to shift due to the sawhead bouncing when the wheel comes off the end of the board but the blade is still 200 mm back in the timber, resulting in the last 150mm of the board being out of grade due to size. Sawmiller A can do it, but it's a big job and it's going to take him awhile.

Sawmiller B has a three knee linebar carriage backed up by an automatic bench: pretty much the old industry standard in the Australian hardwood sector. He's a good operator and knows how to advance and receede his knees to ride the linebar to compensate for log movement, the flitches are coming off at a consistent 52mm. He puts in an initial cut on his bench, then uses the linebar there to keep his timber straight. Orders like this are his bread and butter - it's not a great drama and the biggest complaint he has is that to reduce bow in the boards he's had to turn the log on the carriage a few more times, and lost a fair bit on the bench due to needing to keep face cutting there as the boards pulled. His recovery percentage is about the same as Sawmiller A, but the order is out the door - after much swearing and cursing about cutting bloody poles - by the end of the day.

Sawmiller C has a fully optimised small log system, comprising end dogging carriage with downturns, curtain scanner, twin blades and two chipper reducers per side. From there flitches move down the chain and go to another fully automatic optimised ten blade gang, with top and bottom chipper reducers to sort any oversize. He starts the order at 8.30 am and its packaged ready for delivery at 9.

Under the Qld Western Hardwoods schedule a billet of 250 SED (x 2.4 long) is a compulsory sawlog, so obviously the State of Queensland thinks that's a viable and economically profitable log to mill.
I was being generous making them 450 in this little scenario. Cutting 6x2's from 200 diameter logs with a swing mill can be done, but my experience is that it will cost more in time to do it then it's worth. It literally is a case of better to turn them into garden sleepers, and ideally not to have that log in the yard in the first place. It's a perfectly viable log to mill, and it can be done... but it's not profitable unless you've got gear suited to the task.

(And I know you know all this stuff BTW, but I was elucidating for those here who are less familiar with the issue)

John, I think your right you do have to draw the somewhere as to what goes through the mill and what gets left in the bush
But that happy medium doesn't mean you need to go bigger to get a better profit margin
that in my opinion is only shooting yourself in the foot, better off just picking the right size mill cutting whatever you can get out of your logs and sending it on its way.

Originally Posted by 1thumb

John, I think your right you do have to draw the somewhere as to what goes through the mill and what gets left in the bush
But that happy medium doesn't mean you need to go bigger to get a better profit margin
that in my opinion is only shooting yourself in the foot, better off just picking the right size mill cutting whatever you can get out of your logs and sending it on its way.

Mate, typing all that has made me think. Based on whats happened in the industry elsewhere in the world, Sawmiller B's days are numbered. The little guy can tighten his belt a little at times, pick and choose his orders, doesn't have a lot invested so he can take a day job if he has to if things get quiet, and if the logs aren't much good he just moves on to better pastures. The big guy sets up beside a large plantation resource and makes a small earning per share for all the investors. Any logs too big for his sawline he palms off to whoever is around, or if he's getting enough of them he puts in a conventional carriage to reduce them back to size but that's just a sideshow that gets started up every second Friday.
Sawmiller B gets squeezed out. He's not big enough to compete with the big guy, not strong enough to invest the million or so required for a modern sawline if he did have access to the volume to run it, but too big to survive on a load of decent logs a week. That's whats pretty much happened in the USA, Canada and Europe.

I'm Sawmiller B.

Originally Posted by John.G

Mate, typing all that has made me think. Based on whats happened in the industry elsewhere in the world, Sawmiller B's days are numbered. The little guy can tighten his belt ait little at times, pick and choose his orders, doesn't have a lot invested so he can take a day job if he has to if things get quiet, and if the logs aren't much good he just moves on to better pastures. The big guy sets up beside a large plantation resource and makes a small earning per share for all the investors. Any logs too big for his sawline he palms off to whoever is around, or if he's getting enough of them he puts in a conventional carriage to reduce them back to size but that's just a sideshow that gets started up every second Friday.
Sawmiller B gets squeezed out. He's not big enough to compete with the big guy, not strong enough to invest the million or so required for a modern sawline if he did have access to the volume to run it, but too big to survive on a load of decent logs a week. That's whats pretty much happened in the USA, Canada and Europe.

I'm Sawmiller B.

Agree 100% the small bloke gets pushed out and the consumer has to cop what comes out of the back of one of those big automatic monsters. My old man always said cut a good stick and you will sell It, in the future it will be "this is all you can get so get usedto it"

John, that was an excellent break down. I could almost taste the sawdust. What you are saying is is quite correct, The need for speed is the main driving factor in any mill. I am not suggesting that every log is millable and I agree that some logs dont suit some saws. Not much can be done about that other than specify what the loggers are to supply and that wouldnt go down too well in a lot of cases.
Let me put it this way, in years gone by, a miller would have to cut whatever was locally available. In some cases these logs would be less than ideal milling logs- Houn pine would be a good example. It is no trouble to pick the material that was cut fifty years ago compared to what is produced now. The same thing applies to many other
furniture grade species.
I understand that structural timber and furniture grade are very different kettles of fish and the effort required to obtain best yield from the latter is better rewarded and therefore the time spent is more justified. My point is, a lot of material is being wasted, purely through a low skill level of the operator.
I have been out of the industry for a few years now. But a year ago, one of the owners of a mill I used to do a lot of business with asked if I could supervise the cutting of some Cedar and Rosewood that he had purchased for his own use. For old time sake, I agreed, as the Cedar was pretty nice stuff. The young sawyer was delighted to have something different and was more than prepaired to hand over the controls to me. Of course I declined the offer and said, "She's your baby and you should feed her." The poor bloke didnt have a clue. If he had had his way, he would have chopped it up like any other hardwood log! When I first got the call from the mill owner I was surprised. But once on site and we were underway, I was bloody glad to be there. The young bloke's comment when we finished was, "I've learnt more today than in the last five years." I told him, "It only seems like that." But if I was honest, he was probably right. A good lad, with heaps of potential, but no one to show him the tricks. Sadly, this is common in the mills now. The sawyers are young with little variety in what they are doing so the opportunity to develop their skills is delayed at best.

Interesting way this thread has run.....

Rusty, when you say logs that are left in the yard give an indication of the millers skill, what kind of logs are we talking about

I've come from a background of cutting log from a paddock 'after' the sawmill has already left, and then I took logs to cut timber from. So I figure from that perspective my general log quality was well below what most mills would take - only logs I have now are logs brought in by the logging contractor and I tell ya...MAN oh MAN!!! they are a helluva lot different compared to what I've spent the last 10 years cutting.

We currently have a monthly order for feedstock to NSW, the grading on it means each day there are logs on my skids that I turn down/won't cut and/or leave in the yard. These logs are logs I can see from the ends have pipe bigger than I can fit boards around, they have branch stubs bigger than the width of the boards we are cutting and not just one or two where we can roll it to the 'bottom' but branches on 3 or 4 faces, too small (less than 250mm starts becoming ridiculous), bent so when lined up with heart each end you only get 2 or 3 1" boards full length - these are my sows ears logs, but its limited to spotted gum and for this order. None of those are worth the time to cut to try and get something for this order.

Now if they where Ironbark, tallowood even bluegum, I'd cut every one of them, admittedly I wouldn't reach for them first, I like the idea of giving my customer the best timber I can, but if sleepers where needed, they'd be sliced into sleepers, but to try making them into structural timber just isn't feasible.

That's the kind of log I'm talking about not being able to make a silk purse from.

Originally Posted by Sigidi

Interesting way this thread has run.....

Rusty, when you say logs that are left in the yard give an indication of the millers skill, what kind of logs are we talking about

I've come from a background of cutting log from a paddock 'after' the sawmill has already left, and then I took logs to cut timber from. So I figure from that perspective my general log quality was well below what most mills would take - only logs I have now are logs brought in by the logging contractor and I tell ya...MAN oh MAN!!! they are a helluva lot different compared to what I've spent the last 10 years cutting.

We currently have a monthly order for feedstock to NSW, the grading on it means each day there are logs on my skids that I turn down/won't cut and/or leave in the yard. These logs are logs I can see from the ends have pipe bigger than I can fit boards around, they have branch stubs bigger than the width of the boards we are cutting and not just one or two where we can roll it to the 'bottom' but branches on 3 or 4 faces, too small (less than 250mm starts becoming ridiculous), bent so when lined up with heart each end you only get 2 or 3 1" boards full length - these are my sows ears logs, but its limited to spotted gum and for this order. None of those are worth the time to cut to try and get something for this order.

Now if they where Ironbark, tallowood even bluegum, I'd cut every one of them, admittedly I wouldn't reach for them first, I like the idea of giving my customer the best timber I can, but if sleepers where needed, they'd be sliced into sleepers, but to try making them into structural timber just isn't feasible.

That's the kind of log I'm talking about not being able to make a silk purse from.

Sounds like the Western Hardwoods Schedule... so long as there's no two major defects inside 2.4m of each other it's a sawlog. Pipe up to 60% diameter... it's a sawlog. Bent like a dogs hind leg but the bends are 2.4 apart... it's a sawlog. How many other mills is your contractor supplying and do their logs look the same, or are you two - being the "new" kids on the block - drawing a shorter straw?
If you haven't got a copy of it PM me your email address and I'll send you one, I have it on PDF. Anyone else who wants one do the same.

This, apparently is "to help the industry transition to a plantation based resource". They haven't planted the trees yet (up here at least). And apparently no-one advised them that there is no demand for hardwood shorts in the building sector anymore because internal framing is now all done in pine, and that CHEP is the only hardwood pallet manufacturer of any volume since LOSCAM went to pine 10 years back. There are high value uses for hardwood shorts... but they are cost prohibitive to the little guy to implement. There aren't any little guys on the advisory panel now are there???

What was it Ronald Regan said..."The nine scariest words in the english language are: I'm from the Government and I'm here to help."

Originally Posted by Sigidi

Interesting way this thread has run.....

Rusty, when you say logs that are left in the yard give an indication of the millers skill, what kind of logs are we talking about

I've come from a background of cutting log from a paddock 'after' the sawmill has already left, and then I took logs to cut timber from. So I figure from that perspective my general log quality was well below what most mills would take - only logs I have now are logs brought in by the logging contractor and I tell ya...MAN oh MAN!!! they are a helluva lot different compared to what I've spent the last 10 years cutting.

We currently have a monthly order for feedstock to NSW, the grading on it means each day there are logs on my skids that I turn down/won't cut and/or leave in the yard. These logs are logs I can see from the ends have pipe bigger than I can fit boards around, they have branch stubs bigger than the width of the boards we are cutting and not just one or two where we can roll it to the 'bottom' but branches on 3 or 4 faces, too small (less than 250mm starts becoming ridiculous), bent so when lined up with heart each end you only get 2 or 3 1" boards full length - these are my sows ears logs, but its limited to spotted gum and for this order. None of those are worth the time to cut to try and get something for this order.

Now if they where Ironbark, tallowood even bluegum, I'd cut every one of them, admittedly I wouldn't reach for them first, I like the idea of giving my customer the best timber I can, but if sleepers where needed, they'd be sliced into sleepers, but to try making them into structural timber just isn't feasible.

That's the kind of log I'm talking about not being able to make a silk purse from.

The logs you mention I would expect to find left in the yard. In fact, I would be having a word with your supplier as it sounds to me like you're getting the rough end.
The original thread started out about tension. That was the main issue that I felt was worthy of discussion as these logs are often wasted due to mill skill or lack thereof. The logs you are describing are certainly worse than that. Shorts are a great opportunity for marketing, if you know where to look. There are markets for material as short as 600mm and big volume.
I understand the non viability issue. But that non viability is often the result of a limited market and/or supplying the same market as everyone else. Competition is tough. And when we are all swimming in the same pond, there isn't much room to move.
To explain what Im banging on about; Thirty something years ago, I was involved in the introduction and manufacture of laminated beams in Australia. This started out using full length laminations. We then started testing using butted shorts, followed by finger jointing. The motivation? The need to reduce non viable material
waste. You see, the Company was big...they covered the entire industry, from growing the trees, to exporting the timber. They were getting burnt by waste at so many levels it wasnt funny and their bottom line was showing it. Others in the industry decided to go down the wood chip route. History will be the judge of who made the better choice.

Hi fella's, I' have been watching this thread and I don't know about anyone else but as a novice who likes to learn I haven't learned much about log tension. Don't get me wrong I appreciate what has been said but I just get the feeling there's a whole lot more that could be passed on. Sure it started great then got side tracked on isues like "I like red you like blue". Just sayin'. There are those of us that do mill mostly for themselves or private folks who have something that fell over they would like to see what they can get out of it. What I would like to know is "is there a way to pick a poorly tensioned log when you see it on the ground and a way to mill it to get the best out of it?" Another one is: If you're felling a tree that has a lean what is the best way to lay it under the mill and take out boards. You see guys like me only know enough to be dangerous and most of the stuff we mill is stuff you professionals wouldn't even look at. My guess would be that if the heart is off centre ; that might be a clue?? A fellow I used to know who would do this for me before I had my Lucas, would break down the logs before putting them over the bench saw with an old "widow maker" ( he called it a swing saw. It had a blade extended out the front and straddled the log). Does this help with tension if you Identify a problem log?

Originally Posted by Tim Creeper

Hi fella's, I' have been watching this thread and I don't know about anyone else but as a novice who likes to learn I haven't learned much about log tension. Don't get me wrong I appreciate what has been said but I just get the feeling there's a whole lot more that could be passed on. Sure it started great then got side tracked on isues like "I like red you like blue". Just sayin'. There are those of us that do mill mostly for themselves or private folks who have something that fell over they would like to see what they can get out of it. What I would like to know is "is there a way to pick a poorly tensioned log when you see it on the ground and a way to mill it to get the best out of it?" Another one is: If you're felling a tree that has a lean what is the best way to lay it under the mill and take out boards. You see guys like me only know enough to be dangerous and most of the stuff we mill is stuff you professionals wouldn't even look at. My guess would be that if the heart is off centre ; that might be a clue?? A fellow I used to know who would do this for me before I had my Lucas, would break down the logs before putting them over the bench saw with an old "widow maker" ( he called it a swing saw. It had a blade extended out the front and straddled the log). Does this help with tension if you Identify a problem log?

Sorry Tim, we did get a bit side tracked. Unfortunately it is dificult to put into words what is often a visual thing. For instance, I hate botanical descriptions, give me a photo any day. Tension taming is a bit like that. Nonetheless, there are still some basic identifiers that can help indicate, without having to start into a log with the saw. The obvious ones would be spiral grain, off centre heart, wind lean. Then there are age/specie related causes that are typical to that particular type of tree. ie some cut well young and develop tension as they mature, others are the opposite.One thing that helps greatly is a decent pipe. Particularly in timbers with a mature tension problem.
Breaking down a log is a good way to help relieve tension. But often resawing is the only option when a breaking saw is not available. When it comes to Lucas type mills, probably the best way to approach tension is to have a plan B up your sleeve. Like an order for shorts on the quarter will be able to be cut from a tense log. Or deep sawn thin boards will often hold their shape were as larger material will retain too much tension.
An off centre heart can be at six oclock or twelve oclock. Twelve oclock does give the opportunity to come to terms with any problems early.

http://www.fwpa.com.au/sites/default/files/PN02.1308%20sawing%20regrowth%20part%20A%20WEB.pdf

This is quite technical and does go into the topic in some depth. It does however, amidst all the in depth stuff, answer your questions very thoroughly.

Thanks John, down loaded for future reading

Originally Posted by John.G

http://www.fwpa.com.au/sites/default/files/PN02.1308%20sawing%20regrowth%20part%20A%20WEB.pdf

This is quite technical and does go into the topic in some depth. It does however, amidst all the in depth stuff, answer your questions very thoroughly.

Thanks John, that was the very publication I was thinking of. Your files are obviously a lot neater than mine. I still cant find it.

Originally Posted by dai sensei

Thanks John, down loaded for future reading

Ditto from me. It's nice to have something to help. App'gy accepted Rusty and I will read the info John. Hopefully I can retain enough to keep me out of trouble.
Thanks again.