Log Volume formula Hoppus.

[Dans Issues]

Does anyone know how to construct a formula to calculate log volume in m3?

Length ~ mid-diameter = log volume (m3) under bark

length 2.4m 72cm mid = 0.977m3

m³ via diameter = mid-diameter in cm² x length in meters x 0,000061685 – rounded to the three decimal points
or
m³ via girth = (mid-girth in cm / 4)² x length in meters / 10,000 – rounded to three decimal points.

=(A5/4)2*B5/10000

I have tried to use the Superscript but the 2 does not want to work...

Any takers?

Thanks

 

[gordsky]

Does anyone know how to construct a formula to calculate log volume in m3?

Length ~ mid-diameter = log volume (m3) under bark

length 2.4m 72cm mid = 0.977m3

m³ via diameter = mid-diameter in cm² x length in meters x 0,000061685 – rounded to the three decimal points
or
m³ via girth = (mid-girth in cm / 4)² x length in meters / 10,000 – rounded to three decimal points.

=(A5/4)2*B5/10000


View attachment 58896

I have tried to use the Superscript but the 2 does not want to work...

Any takers?

Thanks

when you say "I have tried to use the Superscript but the 2 does not want to work.." what do you mean by doesnt want to work.??

 

[kevin9999]

I think you're asking how to square a number? If that's the case, then you use the carat ^ symbol (above the 6) followed by the power. So your formula would look like:

=(A5/4)^2*B5/10000

 

[Peter_SSs]

I know virtually nothing about calculating log volumes. However, this description of the calculation does not produce 0.977 for your sample data.

m³ via girth = (mid-girth in cm / 4)² x length in meters / 10,000 – rounded to three decimal points.

Here is the calculation.

22 02 28.xlsm
	A	B	C
4	Girth (cm)	Length (m)	Volume (m3)
5	72	2.4	0.078
Log Volume

Cell Formulas
Range	Formula
C5	C5	=ROUND((A5/4)^2*B5/10000,3)

m³ via diameter = mid-diameter in cm² x length in meters x 0,000061685 – rounded to the three decimal points

This calculation makes no sense at all to me. Diameter is a measure of length so expressing it in CM2 makes no sense.

 

[gordsky]

which log scale rule are you using?? they all seem to produce slightly differing results.

72 cm	2.4 m	1 pcs		Vermont	0.62 m³
72 cm	2.4 m	1 pcs		Doyle	0.69 m³
72 cm	2.4 m	1 pcs		Scribner	0.68 m³
72 cm	2.4 m	1 pcs		Huber	0.98 m³

 

[gordsky]

If you are expecting the result to be 0.977m3 then it must be Hubers (or the irish log formula) you need to use.
It is the same as the volume of a cylinder which is (pi*r^2)*h or area * height. As you have the girth/circumference you need to backword calculate the radius and then put into the formaula. It can be shortened considerably to accepted industry formula below assuming that A5 contains your Mid-Diameter in centimeters & B5 your length in meters

=(A5^2)*B5*0.00007854

 

[Dans Issues]

which log scale rule are you using?? they all seem to produce slightly differing results.

72 cm	2.4 m	1 pcs		Vermont	0.62 m³
72 cm	2.4 m	1 pcs		Doyle	0.69 m³
72 cm	2.4 m	1 pcs		Scribner	0.68 m³
72 cm	2.4 m	1 pcs		Huber	0.98 m³

Huber, Thanks for the above, would you then know how to add an additional formular to remove the bark if the diameter is over bark?

Here how it is removed. for every 100mm of diameter 10mm is removed for an underbark measurement. This deduction continues unto 700mm, after that (>700mm) you continue to remove 70mm. I have tried to make this formular

for mm's and cm's

when you say "I have tried to use the Superscript but the 2 does not want to work.." what do you mean by doesn't want to work.??

Every time I highlighted the 2 in the formular to reduce to superscript it would not do it, however if i put the 2 in a different cell and made it in to superscript it worked. "This could be the user"

 

[gordsky]

Huber, Thanks for the above, would you then know how to add an additional formular to remove the bark if the diameter is over bark?

Here how it is removed. for every 100mm of diameter 10mm is removed for an underbark measurement. This deduction continues unto 700mm, after that (>700mm) you continue to remove 70mm. I have tried to make this formular

for mm's and cm's

Every time I highlighted the 2 in the formular to reduce to superscript it would not do it, however if i put the 2 in a different cell and made it in to superscript it worked. "This could be the user"

why do you need to reduce the 2 in the formula? IT doesnt need to be for the formula to work.
Huber is an overbark formula. Are you saying you require an underbark formula as well.?

 

[Dans Issues]

why do you need to reduce the 2 in the formula? IT doesn't need to be for the formula to work.
Huber is an overbark formula. Are you saying you require an underbark formula as well.?

I thought the 2 needed to be reduced, thanks for the advice.
Yes id like to now how to formulate an underbark calculation from a over bark reading. If you can help I would very much appreciate it. see the above for a description on how we removes bark bark from a over bark reading.

Thanks