Doyle Boardfoot Log Volume
This is one of the most widely use and well as one of the oldest log rules. The rule was developed by Edward Doyle in 1825. The rule states:
"Deduct 4 inches from the diameter of the log, D, in inches, for slabing, square one-quarter of the remainder, and multiply by the length of the log, L, in feet."
This is equivalent to squaring the log into a cant and calculating the board feet in the cant. Doyle assumed 25 % reduction for kerf and shrinkage. The rule can be stated as:
$$ V = \frac{(D-4)^2 L}{12}(1.0 - 0.25) $$
$$ V = \left(\frac{D-4}{4}\right)^2 L $$
where V is the volume in board feet, D is the small end diameter of the log, and L is the log length.
Known issues include:
- The formula is very simple.
- The rule works best for logs between 26 and 36 inches in diameter.
- Larger logs produce underruns.
- Smaller logs produce overruns.
Example
- Imperial Units
- dia small = 10 in inches
- L = 16 feet
- Answer = 36 board feet
- dia small = 28 in inches
- L = 16 feet
- Answer = 576 board feet
- Board feet is a imperial units only system.
Code
This code is stored in my Github.com\larsendr site. These are direct links to the raw code.
Excel® Visual Basic Code
R Statistical Package Code
Python Code
Go Code
Javascript for Node Code
C Code
|
