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Saw Log Volume Calculator vs actual output

Started by Qweaver, April 23, 2012, 12:35:35 PM

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Qweaver

I sawed an oak with my Peterson that was about 34" avg diameter.  The Log Volume Calculator said I should get 463 BdFt International.  I actually got 57 boards 1x8x8'6".  I figure that to be 323 BdFt.  Surely the 1/4" blade kerf of the Peterson will not make that much difference.  Is the calculator set up for a 1/4" kerf?  I had very little waste.  Maybe my math is wrong.  It's pretty simple math tho'
Quinton
So Many Toys...So Little Time  WM LT28 , 15 trailers, Case 450 Dozer, John Deere 110 TLB, Peterson WPF 10",  AIM Grapple, Kubota 2501 :D

Jeff

First, you must use the inside the bark on the small end to get your log diameter for any log scale. Not an average diameter. If you didn't, there probably is your discrepancy.

Also, log scales do not use half feet. The calc formula is the international 1/4 scale.
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

Qweaver

I did use the inside of the bark on the small end.  The log was a little oblong...36"x32" so I figured the average.  I have not checked output vz scale before.  I'll do it again on the next log.
I was really happy with the ease of making quartersawn on the Peterson.  4 of the 57 boards were flat sawn just to get a flat spot to start quartersawing.  Almost all of the rest were 1x8 clear QS.  8)
So Many Toys...So Little Time  WM LT28 , 15 trailers, Case 450 Dozer, John Deere 110 TLB, Peterson WPF 10",  AIM Grapple, Kubota 2501 :D

Jeff

On a log that large it seems you should have had some side lumber other than the 1 X  8s or you had some pretty hefty slabs to get to an 8" face.
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

POSTON WIDEHEAD

Quote from: Jeff on April 23, 2012, 01:28:33 PM
On a log that large it seems you should have had some side lumber other than the 1 X  8s or you had some pretty hefty slabs to get to an 8" face.

Jeff's right. Just asking, Did you have some slabs you could have possibly got some 1x4's and 1x6's out of?
It adds up quick.
The older I get I wish my body could Re-Gen.

stavebuyer

Sounds a little low but while there is good over-run on small logs; logs 30"+ generally won't yield what they scale when cutting 4/4 especially if your sawing a little thick to cover drying and planing.

Ron Wenrich

Let's do a little rough math here.  A 1"x25" piece will give you 3 1x8s with enough for saw kerf.  57 pieces will come out of 19 1x25.  If you were cutting on the inch, then you would need roughly 24" to get your 57 pieces.  That is 1" wood plus 1/4" kerf.  So, a 24x25 would give you sufficient fiber to make your 1x8s.

What happened to the rest of the side cuts?  You lost about 87 bf in sawdust.  Big logs are very hard to make scale.  Its the way the functions work that make up the calculator. 
Never under estimate the power of stupid people in large groups.

dgdrls

what were your raw log length dimensions
One or more logs?

This is an interesting question worth pushing some comp's around for,
well,... at least for me it is :D

DGDrls

Jeff

The log lengths are irrelevant really in the final figures as long as the same length was used for both the log and the lumber when determining footage.
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

dgdrls

I agree, but it would be needed for the original comp, correct?

DGDrls

Qweaver

Yes, I did have a few 1x4s.  4 I think.  Also there was some curve that caused some loss and I guess this all adds up.  Because of the way you saw with the swinger there is very little side lumber loss once I get a flat spot on the top.  I guess that I need to learn how to accurately scale logs that I buy.
So Many Toys...So Little Time  WM LT28 , 15 trailers, Case 450 Dozer, John Deere 110 TLB, Peterson WPF 10",  AIM Grapple, Kubota 2501 :D

POSTON WIDEHEAD

Quote from: Qweaver on April 24, 2012, 04:33:13 PM
Yes, I did have a few 1x4s.  4 I think.  Also there was some curve that caused some loss and I guess this all adds up.  Because of the way you saw with the swinger there is very little side lumber loss once I get a flat spot on the top.  I guess that I need to learn how to accurately scale logs that I buy.

Don't get discouraged, it takes practice. When determining BF, nothings exact. I just do the best I can but I keep my eye out for flaws in the log that will determine the outcome.
These were  GREAT questions you asked. I even learned some things.  ;D
The older I get I wish my body could Re-Gen.

Jeff

Sweep in a log is definitely a deduction in scale.
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

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