Scaling Overview

Scaling Overview
- What are log scaling & grading?
  - scaling: quantity .... spp, & net merch. volume
  - grading: quality ... products
- Why scale (purpose/ uses of data)
  - stumpage
  - cut control
  - contractor payment
  - transactions
  - internal inventory
- Legal Requirements/ Authority
  - Forest Act - part 6
  - Scaling Regulation
  - Scaling Manual
- Units of Measure
  - Logs
    - m3 (dm3)
    - fbm
  - special products
    - stacked (cords) - firewood, shake bolts
    - piece count - stakes, posts
    - lineal (m) - poles/ pilings, house logs
    - mass (kg) - chips
- History
  - counting stumps
  - late 1880's - various "log rules": Scribner (unit: FBM)
  - 1895 BC Boardfoot Log Scale (FBM)
    - method: Vol based on top dia. & length (i.e. cylinder)
    - issues
      - 1" BOARDS as end product
      - ... top end measured, but not butt, so no taper
      - ... loss to kerf
  - 1944 BC (Lumber) Cubic Scale
    - method:
      - Smailian's formula
        
        ave of top & butt * L
        
        taper taken into account
      - 'cunits' (100 ft3)
    - issues
      - suitable for lumber
      - ... not assuming 1" boards
      - ... so no kerf ded'n
      - But
      - ... but still LUMBER based
      - ... 'squaring out' allowed
      - .. allowances for twist, crooks, cracks
  - 1965 BC Firmwood Cubic Scale
    - method
      - still Smailian's formula
      - Close Utiliz'n Stds
      - not lumber based ... SOLID net vol
      - ... deduct rot, char, catface & missing ONLY
  - 1979 BC Metric Cubic Scale
- Log Species & Codes
  - HE, BA, SP, FI, CE, CY, LA, LO, WH, YE, UU
  - AL, MA, BI, CO, AR, AS
- Weight Scaling
  - method
    - weigh all loads
    - scale a few (at random)
    - correction ratio
  - factors affecting the Ratio
    - spp
    - growth rate
    - age
    - moisture content
    - rot
    - bark
    - foreign matter
- Log Measurements
  - Ends
    - measure d.i.b. ... but units RADS
      - end measured across Dia, but expressed in radius
      - 1 rad = 2 cm
    - rad's to nearest cm
    - ave of 2 measures
    - accountant's rule of rounding (to the even)
    - butt flare
  - Length
    - nearest 0.1 m
    - accountant's rule of rounding
    - shattered end - mid-point (to give solid vol)
- The Scale Stick
  - parts: tine, edge, face (side)
  - edge
    - black
      - in RADS
      - rad class = 2 cm (of dia.)
    - red
      - lines in 20 cm segments
      - used for length (now we use tape)
  - face
    - half cylinder volumes
    - in dm3
- Determine gross log volumes
  - 13r / 17r / 8.0m
  - 13r / 17r / 8.7m