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bd ft to ton conversion chart.

Started by ely, December 27, 2005, 03:16:40 PM

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ely

does anyone have knowledge in this area. most wood is sold here by the ton now and i am wondering how that converts to bd ft. thanks. as an estimate only.

beenthere

Go to the "Forum Extras" and find the red tool box, and then to log/board weight chart. Then you will have a bdft weight, and can apply it by species. The estimates are 'rough' at best. Should do your own to double check what you get out of a "ton" of wood to know best.  Or scale some logs using the Int'l scale and then relate that to the weight of the whack of logs of concern.
south central Wisconsin
It may be that my sole purpose in life is simply to serve as a warning to others

ely

thats why i hang out here, always someone ready to help out the slower crowd. thanks for the quick response.

SwampDonkey

Varies by juridiction. I don't know what use it would be to convert from tons to  board feet. Since the your slab wood (sometimes bark) is combined in the weight, how do you account for that volume when your thinking in terms of lumber? A log isn't 100 % lumber.

Here are some figures: A metric tonne is 10 % larger than a short ton. A more meaningful conversion would be to cords or m^3 and even that conversion varies with the seasons. One of the pulp mills here always adjusted for seasonal differences and called it a 'seasonal differential'.

Hardwood and birch: 2.5 tonne/cord, 2 cord per thousand, 5.5 ton/thousand

Poplar : 2.2727 tonne/cord, 5 ton/thousand

Softwood: 2.05 tonne/cord, 4.5 ton/thousand
"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)))

Ron Wenrich

A rule of thumb in this area is that it takes 6 tons of logs to make 1 Mbf of wood.  That would be primarily oak and mixed hardwoods.  Slabs and edging strips will yield about 2 tons/Mbf and sawdust will yield about 1 ton/Mbf. 

It won't work that way for every log or every species or every cutting pattern.  But, for long term planning, it works out OK. 
Never under estimate the power of stupid people in large groups.

ely

i was wondering about that, i just burned up a perfectly good calculator this afternoon :-[. all i could gather was 3000 lbs of white pine was 1000 bd ft and with the prices at the mill of 22 cents a bd ft on pine it just does not make sense to me. i figured it out that 666 bd ft was in one ton of white pine,but at the other mill they pay54 dollars a ton for pine. if you scale the same load you would recieve 146.52 dollars for the pine. something is not computing for me. ::)

bberry

Ely
There are charts showing the weight of specific woods per board foot. Just multiply x 2000. I have seen the charts but don't know where they are. Put Doc to work over at the Woob Web Forum.

sawhead

In the back of the NHLA  grade book is conversion chart for tons to mbf for differant hard wood species.
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extrapolate85

What type of wood are you wanting to convert? The price you mentioned ($54/ton) sounds like a Southern Yellow Pine small sawlog price. Using Doyle with an average small end diameter of about 10" on 16' logs you will run about 10 tons per thousand, but this ratio will change a lot given bigger or smaller logs (16" - 16' logs will run about 6 tons mbf Doyle). A lot of the mills in your area convert SYP at 3.59 tons/cunit (a cunit is a 100 CF). Yield out of a 100 CF of SYP logs will be about 800 BF (cutting 8/4" dimension), so the mill would recover roughly 222 BF of lumber out of a ton of logs. At 10 tons/mbf Doyle log volume, the logs would scale 100 BF per ton giving a 222% recovery in lumber BF. Assuming a lumber sales average of $350/mbf you would get $78 worth of lumber, about $9.40 worth of chips, and maybe $2.00 worth of sawdust and shavings out of that ton of logs ($89.40 in revenue). With a $159/mbf manufacturing cost lumber scale (89.40 - 54)/0.222), the mill would break even at $54/ton. If their manufacturing cost is less than $159/mbf; they make a profit.

If you are talking about something other than SYP small sawlogs and can give more specific information, i.e., species, average small end diameter (inside bark), I can get you much better information on the ton conversion.

IL Bull

That made me dizzy.  Who would of thunk? :D :D
Case Skid Steer,  Ford Backhoe,  Allis WD45 and Burg Manual Sawmill

ely

extra, that is interesting info. the 54 dollar /ton price is for butt cuts only with a 20 inch min. small end and 12 ft long in think was the length. in wright city okla. and it is for syp

Ron Wenrich

Here's some weight to Doyle conversions from the forestry handbook:

                                  12" dia          18" dia        24" dia

loblolly pine              12,400              8,700           7,400
longleaf pine            11,100              7,700           6,500
shortleaf pine           10,400              7,200           6,100
slash pine                 12,200              8,500           7,200

How do you buy mixed grades by weight?
Never under estimate the power of stupid people in large groups.

SwampDonkey

Fraser Papers for a time had 4 grades for their softwood pulp. Everyone complained that they would always get degraded to the lowest grade, so the system got scrapped and they don't except any rot in the sticks (well <= 2 %). They used to take it as long as it held together in their lower grade, but it didn't pay to cut it and alot of people left alot of bucked off stuff in the woods to try to increase the grade. The new system didn't improve the bucking, but discouraged alot of people from bringing alot of junk wood. I told one guy not to bother hauling what I saw on his load because they'de turn him down. He goes ahead anyway, and they sent him out of their yard with the whole load.  ::)

"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)))

RMay

RMay in Okolona Arkansas  Sawing since 2001 with a 2012 Wood-Miser LT40HDSD35-RA  with Command Control and Accuset .

extrapolate85

Those numbers from the forestry handbook don't fit with my experience for SYP. They are way too optimistic. 12" - 16' logs will run about 7.8 tons/thousand Doyle and even 12" - 32' logs will run just over 6.9 tons thousand (maybe the mill was giving two barks and had a short-thumbed one-eyed scaler). Syp will average about 68.6 lbs/CF gross and about 71.8 lbs/CF net and it averages right at 0.1" taper per foot. I used to do a lot of work in the south and can assure you that those numbers will get you close. to find the weight of a log, calculate the cubic ((small end diameter squared + large end diameter squared) x length of log with trim in feet)) x .002727 = CF. Multiply the CF times 68.6 and you will get the weight. Doyle is (diameter -4 squared) x Length without trim/16 = BF. I would stick to logs 20' and shorter for playing around with these numbers.

P. S. The mill that is paying $54 ton is paying roughly $280/mbf Doyle for a 20" log.

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