% upscale for estimating log volume needs?

[quadracutter222]

I'm trying to put a job together where I will be getting a cut list (6x6, 6x12, 2x6) and need to come up with a volume of Doug fir needed.

Cut list board feet to m3 is easy, but what is a safe round up factor to get m3 (or any volume unit) of raw logs?  I'm thinking somewhere in the 30-50%

Thanks !

[Den-Den]

I doubt that a simple factor will work, am thinking that log size has a significant impact on the factor.
Might also be affected by the ratio of 2x lumber to beams.  With smaller logs, one heart centered beam per log may be all you get.  If there is a lot of 2x lumber and a few beams, this is not an issue.  If the logs are big enough to cut FOHC beams, it is less of an issue.

[WV Sawmiller]

   The size of the order will also affect any proposed percentage extra. For a small order one more log might represent a much bigger % change than on a big order. I would think the bigger the order the smaller % fudge factor you would need. I guess it goes without saying but I'd cut the biggest pieces out of my biggest logs first. That way any mis-cuts or bad spots can possibly be re-sawed into other items on the cut list. Good luck.

[longtime lurker]

 All depends on the size and grade of log... takes a lot of log to get a heart free 12 x 6, boxed heart not so much. Same with 6 x6's....under grade rule here they must be heart free at that size and it takes a lump of log to pull them out of. Dont need much log to get a boxed heart 6x6 at all tho

6 x 2's....again big logs are easy, you start cutting them out of 15" SED's or smaller and your target size recovery drops rapidly.

Good logs I work on 42 percent, and I'll call a good log anything with a SED 3 times my target width (so 18"logs for 6 x 2). Bigger again just makes it easier. (Real good logs I expect somewhere between 48-52.)
Cutting my normal selection of culverts and toothpicks I work on 30. 
Both of those are conservative but better to have too many than too few, and every so often I get my head handed to me by a load. I actually get nervous when the average starts to sneak too high, for the simple reason that I know that I've got a hiding coming to bring it back to normal.

[quadracutter222]

Thanks for all the valuable information guys!  I will let you know how this one works out

I have yet to crunch the numbers from my last job, but have lots of data to drive total m3 cut and fbm yield, which will give a good recovery factor for that job, oh and flitches to saw first.

A sawyer I am learning from goes with 250-300 fbm per m3 as a rule on his Mobile Mill.

[WV Sawmiller]

I am confused (again) at that. I just checked and found there are approximately 61,024 cubic inches in a cubic meter and when I divided 61,024 by 144 (cubic inches in a bf) I get just under 424 bf in a cubic meter. A little help here?

[quadracutter222]

I am confused (again) at that. I just checked and found there are approximately 61,024 cubic inches in a cubic meter and when I divided 61,024 by 144 (cubic inches in a bf) I get just under 424 bf in a cubic meter. A little help here?

That 250-300 fbm would be post milling yield potential per m3.

[donbj]

"A sawyer I am learning from goes with 250-300 fbm per m3 as a rule on his Mobile Mill."

Those numbers are accurate recovery per m3. I'm a log scaler and own a LT40HD and have scaled many jobs and my recovery lands in that ball park as well.

[WV Sawmiller]

   Sorry but I am still confused. I thought it was a simple math question and don't see how I can be that far off unless my conversion source data was wrong. Kind of like saying a gallon is now 2.84 quarts or 6.9 pints or such? ???

[Ianab]

  Sorry but I am still confused. I thought it was a simple math question and don't see how I can be that far off unless my conversion source data was wrong. Kind of like saying a gallon is now 2.84 quarts or 6.9 pints or such? ???

The confusion is that a cubic meter of log wont saw out a cubic meter of lumber. 
When logs are measured by the m³, it's a measure of the true volume of that tapered cylinder. Then take off the slab wood and sawdust, and you get a smaller m³ of lumber. 
Question is how much smaller, and that depends on the logs and what you are sawing. 
This differs from using a "log scale" that estimates the bd/ft that you should be able to recover. If you were to "scale" that 1 m³ log it would probably come out at 250-300 bf/ft.  But 1 m³ of lumber is ~424 bd/ft. 
The missing % is the slabs and sawdust.
It's similar to buying logs by the ton. A ton of logs wont make a ton of lumber, and a m³ of logs wont make a m³ of lumber either.   

[WV Sawmiller]

Ian,

   Thanks for the clarification. I am thinking bf vs cubic meter of sawed lumber and you are talking about logs. 

"I see said the blind man to the deaf wife on the telephone...."