This 36" fibreglass ruler can be used to calculate the number of board feet in a log up to 30" in diameter.
- graduations in 1" class with break at 3/4"
- measures volume in 1" diameter classes for 10 log lengths from 8 to 17 feet long
- defect deductions shown for 20%, 25%,33% and 66% that can then be deducted from the gross diameter of the log.
- crayon holder in handle
- can be used by right and left handed scalers