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Size does matter

Started by GeneWengert-WoodDoc, March 03, 2013, 09:13:04 PM

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Jeff

Quote from: Tree Feller on March 04, 2013, 10:08:48 AM
Quote from: Magicman on March 04, 2013, 09:14:48 AM
My BOTTOM LINE, is the real world.

The real world or just your world?

That's about enough of that.
Just call me the midget doctor.
Forestry Forum Founder and Chief Cook and Bottle Washer.

Commercial circle sawmill sawyer in a past life for 25yrs.
Ezekiel 22:30

GeneWengert-WoodDoc

In my first posting I stated "Now, let's assume that just to be sure, you add 1/16" extra to the width and thickness, but you really would not have to."  The point was that extra addition of thickness WHEN YOU DO NOT HAVE TO is costly.  The language did not imply that the correct size is as given in the example. 

I also stated "the point I was trying to make is that a small extra thickness or extra width (1/16") makes an important difference in yield.  I was not trying to suggest that 1-3/4" x 5-7/8" is the correct size."

Show me where I posted an absolute number on size and I will change it promptly.

So, I see no indication of me specifying an "absolute figure" that would be used by a sawyer.  That is, I would never ever post or suggest absolute oversize figures to someone because doing so would be a disservice to them and their customers.  The customer controls what we need.  As I also stated " One key for hardwood lumber is that after drying, the customer needs the thinnest piece to be 15/16" thick.  (Whatever value the customer wants can be used.)"  There is no question that the customer determines what the appropriate size is--3/4", 15/16", or whatever.  I thought that I was crystal clear on this.

The point of the posting is to show what an extra amount, an excessive amount of size can mean.  Can I be more clear?

Note that 5% increase or decrease in yield applies to small or large operations as far as excessive size goes.

One mill I managed cut well under 1 million BF per year, so I do know about small mills.
Gene - Author of articles in Sawmill & Woodlot and books: Drying Hardwood Lumber; VA Tech Solar Kiln; Sawing Edging & Trimming Hardwood Lumber. And more

red oaks lumber

i've seen many many times. customer brings lumber in for planing that wasnt sawed thick enough, who looks like the incompentant one ? me, last one to handle the wood.
gene, even a mill that cuts a million b.f is not small by most everybody on here is concerned.it starts to get dangerous talking about cutting smaller and thinner to recover more wood (maybe).
so having planed over 30 million b.f of lumber of various sizes and species cut from several dozen sawyers, my obsevations have been cutting thinner lumber gives a higher % of lumber that didn't cleanup at the set size, less room for blade wave or miss calculation.just my veiws
the experts think i do things wrong
over 18 million b.f. processed and 7341 happy customers i disagree

GeneWengert-WoodDoc

I did say WELL UNDER 1 million.  Some years it was closer to 100,000 BF.

I am talking about excessive thickness, and not about making lumber so thin that it fails to clean up or is too thin for the customer.

If there are pieces that are too thin, certainly the size needs to be increased.
Gene - Author of articles in Sawmill & Woodlot and books: Drying Hardwood Lumber; VA Tech Solar Kiln; Sawing Edging & Trimming Hardwood Lumber. And more

Jeff

The about enough was to everyone involved. If you want to go, so be it. Gene wengert is a big boy, he can fight his own battles. He doesn't need you to jump in and make remarks. If you don't like my way of doing things, so be it. People can be insulted in two directions remember. Looks to me like there is a tone that is growing on the Forestry Forum and it is going to be changed, I can tell you that right now.  There have been several little exchanges by members, and I've been getting way to many complaints from way to many people stemming from the same problem.
Just call me the midget doctor.
Forestry Forum Founder and Chief Cook and Bottle Washer.

Commercial circle sawmill sawyer in a past life for 25yrs.
Ezekiel 22:30

CalebL

If my post came off as insulting or derogatory, that was not the intent.  That is one thing I hate about email and the internet.  You don't know what tone people are using. 
2005 LT40 HDD34
2000 Cat 226 Skid Loader

Cedarman

When sawing long cedar 12 to 20', if an extra board can be gained by sawing a 1/16" thinner,  4 cuts is 1/4".  That can once in a while make an extra 2x12. Otherwise a 1" x12" and 3/4" x 8 or 10" , both boards would go into a sell later pile.  A 2x12 x 20 is worth  $100.00  Well worth taking the time to be sure of log placement and saw as thin of a board as can be done and still have a good board.
Cedar logs big enough and long enough to get these boards are rare and valuable.

But lets take  more common logs and lumber.  If I can get an extra 4' per hour ( 1  1x6x8) then I have an extra $4.80 out of wood that would make planer shavings  or be sold in a thicker than necessary board.  We saw 7/8" to 15/16", dry and plane S2S to 3/4 with very , very few skips.  This is for internal use.  For sale would be 15/16 to 1" for those who will plane for themselves.
So, if I can put an extra $4.80 per hour to the bottom line, then in 8 hours it is an extra $38.40 per day,   $9600 per year,  or $96000 in a decade. 

This is why big mills work very hard to have machinery that will increase yield from every log they run through the mill.  It is why they scan logs and use that in combination with the value of each size board to squeeze each log to get the greatest profit.

One reason I like our 2 saw scragg is that it takes opposite sides off the log, thereby releasing tension equally keeping cants and lumber more uniform.  I want them plus or minus 1/32 from target size.

When moving the mill, I move it 3/32 at a time when I am trying to squeeze an extra board.

I like playing with the numbers to see what is the maximum potential I can get. 

I don't come close to getting the full potential of every log, but I push in that direction.

If a customer wants a board an 1/8" plump , then by all means do so.  But you should know how much your yield is being decreased and add that cost into the cost of the plump board.  I think your customer should be paying for what they are getting.
I am in the pink when sawing cedar.

SwampDonkey

Quote from: GeneWengert-WoodDoc on March 04, 2013, 07:36:29 AM

The idea of having planer shavings (or other offal) offset the extra thickness losses is indeed valid and should be seriously considered.  In many cases, however, a ton of lumber is worth 50 to 100 times more than a ton of planer shavings.  If this wasn't true, then we would chip a sawlog into shavings instead of worrying about lumber and get more money. 

BOTTOM LINE:  A little bit here and there when sawing adds up to a 3% more dollars over a week or month.

Gene this is "usually" true or at least the idea that lumber is worth more than dry planer chips. However, here in New Brunswick we have seen thousands of cords of spruce sawlogs chipped for the pulp mill. This happens on public forest when logs are in a surplus to the sawmill and there is over capacity on the pulp mill side.**  The reason for this is that a license holder is allocated a fix volume of wood and it is harvested according to management plans and DNR targets for revenues. It doesn't matter if the sawmills of the license can only saw so much, the volume has to be cut and most all blocks are clear cut, so it all goes. Many times blocks of spruce have been selected for single tree or group selection. They just blow down. That only works in hardwood.

**This over capacity is somewhat relieved since the melt down, but the harvest levels remain, surplus is now exported. This at one time was forbidden by the Crown Land and Forests Act of NB. What it has done is drive the stumpage price down because of surplus pulp.

A ton of dried chips off the planer mill is worth more than green chips out on the harvest landing. Currently "green" softwood round wood is nearly $50/metric tonne while sawlogs top out at $60 or so. And yes, when your talking hardwood logs like cherry and maple the margin is much wider for the top end of the grade. However another head scratcher. Back in the 1980's millions of cords of hardwood growing on NB public land was all debarked and chipped on the landing as fast as they could cut it. Saw logs and all, all into the grinder.

So, in my experience there must be good money in those chips. ;) Three percent makes sense if the volumes processed are there. Also, the estimates are closer with high volumes than they are low volumes. Your own 'Wood Handbook' will tell you that shrinkage estimates are more reliable with large volumes than they are with small sample sizes. They used an example with Douglas Fir and looked at tangential shrinkage from a sample taken from the same growing site in the forest. The results said it was impossible to reliably predict on a small scale. When you look at the graph, the points were all over. You can see the trend , but not really the slope of the line or how high above the X-axis. So, basically in the back yard I don't know that the 3% even comes up. It's kind of funny in a way to. Yield is what it is, but the scaled estimates on the purchased wood can vary quite a bit from Doyle to International versus the over run. Probably the overrun is a fair bit higher than the 3 % your worried about. A mill doesn't mind using the most favorable log rule, and then worry about 3 %? ::) I think if the mill is that close to folding, it's gonna happen anyway. I'm just using that as an example as you are, might as well use the same numbers.
"No amount of belief makes something a fact." James Randi

1 Thessalonians 5:21

2020 Polaris Ranger 570 to forward firewood, Husqvarna 555 XT Pro, Stihl FS560 clearing saw and continuously thinning my ground, on the side. Grow them trees. (((o)))

Peter Drouin

Quote from: Cedarman on March 04, 2013, 06:16:56 PM
When sawing long cedar 12 to 20', if an extra board can be gained by sawing a 1/16" thinner,  4 cuts is 1/4".  That can once in a while make an extra 2x12. Otherwise a 1" x12" and 3/4" x 8 or 10" , both boards would go into a sell later pile.  A 2x12 x 20 is worth  $100.00  Well worth taking the time to be sure of log placement and saw as thin of a board as can be done and still have a good board.
Cedar logs big enough and long enough to get these boards are rare and valuable.

But lets take  more common logs and lumber.  If I can get an extra 4' per hour ( 1  1x6x8) then I have an extra $4.80 out of wood that would make planer shavings  or be sold in a thicker than necessary board.  We saw 7/8" to 15/16", dry and plane S2S to 3/4 with very , very few skips.  This is for internal use.  For sale would be 15/16 to 1" for those who will plane for themselves.
So, if I can put an extra $4.80 per hour to the bottom line, then in 8 hours it is an extra $38.40 per day,   $9600 per year,  or $96000 in a decade. 

This is why big mills work very hard to have machinery that will increase yield from every log they run through the mill.  It is why they scan logs and use that in combination with the value of each size board to squeeze each log to get the greatest profit.

One reason I like our 2 saw scragg is that it takes opposite sides off the log, thereby releasing tension equally keeping cants and lumber more uniform.  I want them plus or minus 1/32 from target size.

When moving the mill, I move it 3/32 at a time when I am trying to squeeze an extra board.

I like playing with the numbers to see what is the maximum potential I can get. 

I don't come close to getting the full potential of every log, but I push in that direction.

If a customer wants a board an 1/8" plump , then by all means do so.  But you should know how much your yield is being decreased and add that cost into the cost of the plump board.  I think your customer should be paying for what they are getting.

and I agree


I try to get all the wood I can get from a log, I have a lot of money in logs this time of year, I think the roads will be posted in the next day or two,then I get no wood :D but I do see when if a mill cuts 35,to 40,000 bf a day 3% is a lot.

but for me I can't cut enough wood to go commercial, I had a guy from maine thats wants 30;000 bf a week of matt wood, all hard wood, and pay .50 a bf. I can buy hard wood for .25 to .40 a bf [ pallet logs 14' and 16'] 10" and up. for me I can't do that. but a big mill can, when your on a small margin you need to put the wood out  :) :)
A&P saw Mill LLC.
45' of Wood Mizer, cutting since 1987.
License NH softwood grader.

GeneWengert-WoodDoc

Excellent and interesting post "SD".  Indeed, my comments were "in general" and I appreciate your clarification.

When you say "your Wood Handbook" I should say that I had nothing to do with it, BUT THANKS...or did you mean that "your" refers to USA CITIZENS?
Gene - Author of articles in Sawmill & Woodlot and books: Drying Hardwood Lumber; VA Tech Solar Kiln; Sawing Edging & Trimming Hardwood Lumber. And more

SwampDonkey

My mistake Gene on the 'your', I had scanned down through acknowledgments some time ago and noticed yours in the list.
"No amount of belief makes something a fact." James Randi

1 Thessalonians 5:21

2020 Polaris Ranger 570 to forward firewood, Husqvarna 555 XT Pro, Stihl FS560 clearing saw and continuously thinning my ground, on the side. Grow them trees. (((o)))

Cedarman

When it comes to shavings, different species can have huge differences in their shavings value.  American Wood Fibers makes huge volumes of cedar shavings at their plant at Lebanon Ky.  They use  lots of good saw logs, cull logs and some slab wood purchased from other cedar sawmills.  In their case , shavings are a primary product.  Pine is being used now.  Our area of the country has a lot of pine.  Nothing like down south, but still a huge amount.  The pine has never been thinned and is just about free to buy standing.  There are no pine mills and trucking it to the big mills would be cost prohibitive.  So shavings are a reasonable use.  Lots of chicken and turkey houses in Ky and In.

In most cases, you want to get the minimum amount of planer shavings it takes to make a well manufactured board.

It is my job to get the greatest profit from every log in the most economical manner possible in the shortest time possible.  It takes a pencil with lots of lead and trial and error to see what works the best.  Every operation is different, but the basic principles are the same.   
I am in the pink when sawing cedar.

woodmills1

James Mills,Lovely wife,collect old tools,vacuuming fool,36 bdft/hr,oak paper cutter,ebonic yooper rapper nauga seller, Blue Ox? its not fast, 2 cat family, LT70,edger, 375 bd ft/hr, we like Bob,free heat,no oil 12 years,big splitter, baked stuffed lobster, still cuttin the logs dere IAM

Brucer

I was thinking about this over coffee this morning.

I did my calculations based on the range of log sizes I would normally saw up into 2x6's if a customer was willing to pay 3x what it would cost in a box store. I discovered last year that some customers will pay that in order to get Douglas-Fir instead of SPF, full dimension lumber, and no wane!

I used Gene's example dimensions just so's I could compare my number to his. I thought he was pretty clear that it was an example. In any case, it's the extra 1/16" that matters.

Gene mentioned 500 pieces, and I assumed that they would all be the same length, so taper didn't enter into my numbers.

I did two sets of calculations, one set using the smallest diameter log I would use, and one set using the largest diameter I would use for this purpose. The smallest diameter gave me 7 pieces of 2x6, with or without the extra 1/16". The largest diameter gave me 8 pieces of 2x6, with or without the extra 1/16". Seemed pretty straightforward -- no advantage to saving that extra 1/16".

However (amazing what a cup of coffee will do) ... I started thinking about the difference between 7 pieces out of the smaller log and 8 out of the larger log. My logs aren't extruded to exact multiples of one inch ;D so I get the full range of possible diameters between minimum and maximum.

Somewhere in between the min and max there is a transition diameter where I go from getting 7 pieces from the log to getting 8 pieces from the log. If I add an extra 1/16" to each piece, that transition diameter gets larger. So without the extra 1/16" I will get more opportunities to recover 8 pieces instead of 7.

Using Gene's example dimensions I figured I would get 3.1% more pieces without the extra 1/16". So my original reasoning was flawed.

Having said all that ... I know from experience that if I try to keep bumping the mill down to the nearest 1/16" I will make a mistake from time to time and ruin a piece of wood. If I do that every 4 logs I'll lose any gains I may have made. On the other hand, I rarely make a mistake bumping down to the nearest 1/8". I do it all the time.

So, if I'm producing large volumes of one size of smaller stock, I will stick with what I know is safe. If I had some kind of setworks, on the other hand, I would be programming it to squeeze out that extra 3% or 4 %.

Now on the bigger timbers, no one is asking for stuff to the nearest 1/16". But some folks will tell me there are planning to plane the timber to 1/2" below nominal size, which is the standard for green timbers. So I will ask them if they want it sawn to 1/4" below nominal, meaning they will have 50% less planing to do. "How much?" they ask. "No charge".  If we're talking free of heart timbers I can knock 1/2" off the diameter I need and that will save me 9% in log costs. Both parties win :).
Bruce    LT40HDG28 bandsaw
"Complex problems have simple, easy to understand wrong answers."

GeneWengert-WoodDoc

Wow!  All this good info on just one cup?  How big is the cup and what brand of coffee?  Thanks for saying more clearly what I was trying to show and giving a better perspective.
Gene - Author of articles in Sawmill & Woodlot and books: Drying Hardwood Lumber; VA Tech Solar Kiln; Sawing Edging & Trimming Hardwood Lumber. And more

Cedarman

Brucer, would you might getting another cup of coffee and think it through if you were sawing 1" lumber.  We saw a tremendous amount of 3/4".  I am thinking the thinner the pieces, the more critical controlling thickness is. We used to saw a lot of 5/8".  We would set the resaw at 1/32" over 5/8". We used to ship it all off, but now make T&G with it. After drying, planing to .60 to .61 to clean up worst face, then run it for T&G at .54".  We get 98% clean up.  And after sanding, most of the skip cleans up.  We get a lot more reject from blown knots, then skips.

Back in the late 80's when we started sawing cedar for Cedarworks, they would not take any lumber.  I was getting clogged with all the jacket boards from sawing the 3 1/2 squares for mailbox posts.    I decided to visit their plant and see what all they did.  During the tour I noticed that they used a lot of lumber that was made in house from cants from other mills.  I asked why they didn't buy lumber and they said the mills were not accurate and it didn't fit their system.  I said we could do it by planing the worst face to the thickness they need and provide the 3 widths that worked in their system.  It was a lot of work to plane a tractor trailer load of lumber, but we got rid of a bunch of lumber and got paid for it.  After they got the lumber and used it, they said to just saw to the final thickness, 5/8", and send it on the truck with posts.  So we would have 1/2 mailbox posts and 1/2 lumber.  They were surprised we could keep the tolerances with the two WM mills that we were using.  Our window was exact thickness to 1/16" over.    At this point they said you saw it and we will buy it.  Onward and upward we went for 20 years until they were bought out and a whole new world order developed (another story).
My point in this is that you can make consistent thickness lumber in volume in a production mode with bandmills.

I find these thinking exercises very enlightening. I have done many of them over the years. After the mental work,  the next step is log on the mill to see if chalkboard meets the true board.  Then you adjust the thinking and do it again until it works for you.
I am in the pink when sawing cedar.

isawlogs

 I'm switching to milk in the mornin'   ;D
A man does not always grow wise as he grows old , but he always grows old as he grows wise .

   Marcel

Brucer

The coffee just got the mind in gear. There's only a few things I'm competent to do before I have my morning coffee. One of them is to light the fire, another is to make coffee :D. I did the actual math with the computer later in the day.

For the 1" stuff, I always saw it at 7/8" unless the customer asks for the full inch. Basically drop the head one inch each time and the kerf is close to 1/8". No setworks required. This makes it easy to pull off side lumber as I work down to the timber I'm aiming for. It's thick enough that a customer can plane it on a small thickness planer to 3/4". Good enough for fencing and board and batten siding if used rough.

I was asked to cut bevel siding last year but didn't have the equipment. I suggested 5/8" x 8" boards that could be lapped. The customer tried it and loved it. That one's easy to saw, too, because I'm just dropping the saw head 3/4" to get a board. That 1/4" less thickness often made the difference between a piece of nominal 1x6 or a piece of 8" siding.

Sawing accuracy is important when you're trying to get that extra 3 or 4% of recovery. Some woods move a lot when they're being cut (e.g., WRC) and you have to know how to deal with that before you start shaving off that extra 1/16".

Blade alignment and blade condition are critical, as well. My sharpening guy has been buying more equipment to meet the growing demand for his services ... and his quality has gotten very erratic. I ruined a lot of wood last year because I'd never know if his blades would cut true or not. That's getting fixed right now.

Like Cedarman, I do a lot of thinking about how to generate more income from a log without spending more time or money doing it. Then I try it out and see what happens. They thing I found important is to always step back and look at the whole picture. My goal is nearly always one or more timbers in the heart of the log so I aim for lumber thicknesses that I can easily add to my target height with little chance of making an error.

Gene, the coffee is ground from a special mix of different beans that are sold at a local shop. No one will divulge the mix but you can buy it if you're in town. You just have to ask for the "Robinson" blend  ;D.
Bruce    LT40HDG28 bandsaw
"Complex problems have simple, easy to understand wrong answers."

SwampDonkey

Is that the one they use the bat droppings in? :D
"No amount of belief makes something a fact." James Randi

1 Thessalonians 5:21

2020 Polaris Ranger 570 to forward firewood, Husqvarna 555 XT Pro, Stihl FS560 clearing saw and continuously thinning my ground, on the side. Grow them trees. (((o)))

RynSmith

More importantly, does the mention of coffee count as bringing this thread around to food?   ;D

GeneWengert-WoodDoc

I had a customer in VA that made bevel siding from a 2x6 that he re-sawed diagonally, corner to corner.  Lots of people liked the small reveal, but others wanted more so he also did 2x8s, but sales were not as good. He used syp, treated and untreated.  the neat thing is that he doubled the square footage.

I had another client that made siding by taking a dry 1-1/2" thick actual size, and 6" wide (no certain of exact size), with the two faces planed smooth.  Then re-sawed with a band down the middle to make two pieces about 5/8" thick.  In addition to doubling the square footage, the user had the option of rough side out or smooth side.  Some was interior paneling and even had four different colored stains.  Some was for exterior.  Cedar was the main species.

Maybe one of these approaches is an opportunity for you.
Gene - Author of articles in Sawmill & Woodlot and books: Drying Hardwood Lumber; VA Tech Solar Kiln; Sawing Edging & Trimming Hardwood Lumber. And more

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