THE MEASUREMENT OF PIECE PRODUCTS 477 



370. Inspection and Measurement of Piece Products. Piece products, while 

 graded on basis of dimensions, maj' be rejected either because of scant length, thick- 

 ness or width, below requirements for lowest grade, or because of disqualifying 

 defects. As these products are usually hauled to track or landing before being 

 graded, considerable losses are occasioned by failure to conform to these specifi- 

 cations. 



Although the character and amount of defect disqualif j'ing a piece is usually pre- 

 scribed as exactly as possible in the specifications, yet there is always considerable 

 latitude exercised by the inspector, and the closeness or laxity of inspection may 

 vary under instructions according to the demand for the product. This method of 

 regulating supply supplements price adjustments and is open to serious objec- 

 tions. Good inspectors are thoroughly familiar with the qualities required of 

 product and display a certain leniency in judging pieces which almost conform to 

 specifications, provided the general run of the product is of good quality and work- 

 manship. An inspector must command respect for his integrity and reputation for 

 giving both parties a square deal. 



The contents of various classes of piece products may be desired in terms of either 

 cubic feet or board feet, in order to reduce different kinds of products to terms of a 

 common standard or to simplify terms of payment or of record. Since most of these 

 products are exposed to decay, and their value is measured by their resistance to 

 fungus attacks, wood preservation is becoming more prevalent. Creosoting plants 

 base their charges upon the cubic contents of such pieces as are treated as a whole. 



The volume in cubic feet of poles of different dimensions is obtained by the for- 

 mula? given in § 27 by applying the values for cubic volumes of cylinders shown in 

 Table LXXVII, Appendix C. The middle diameter measurement is the most 

 accurate method for long poles, owing to the errors resulting from large butts. 



For short poles, piling or mining stulls, the middle diameter measurement is 

 probably the most satisfactory, and the table of cylindrical contents, or Humphrey 

 caliper cordwood rule will suffice as a standard. Prices for mining stulls of different 

 lengths and diameters sold by the U. S. Forest Service in Montana, are based 

 upon the cubic contents of pieces of each standard size. 



Smaller material such as fence posts or other round pieces may be converted to 

 cubic feet by the same means. 



Cross ties, on account of uniformity of size, are converted into their equivalent 

 in board feet, and expressed either by average contents per tie, or by the number of 

 ties per 1000 feet B. M. The average contents of hewn ties may be obtained by 

 scaling a large number as logs 8 feet long. Or their cubic contents may be cal- 

 culated from the thickness and face and reduced to board feet. The first method 

 deducts for sawdust, and the second for squaring the tie. By either method a 6- by 

 8- inch tie scales about 32 board feet, or 30 ties per 1000 feet B.M. Ties 85 feet long, 

 7 inches thick by 9- inch face may average 40 to 44 board feet, or 25 to 23 per 1000 

 board feet. 



Ratios are easily worked out on the basis of specifications and actual scale, and, 

 once determined, may be substituted for measurement and applied to the count of 

 ties, separately for each size class or grade of tie. 



To reduce piling to board feet, pieces are sometimes scaled directly by a log rule. 

 For small poles, posts or mining timbers the best method of conversion is to apply 

 a converting factor to the cubic contents of pieces of given dimensions. Where 

 total or actual cubic contents is measured, the best ratio is probably 5. .5 board feet 

 per cubic foot. If cubic contents includes only the cylinder measured at small end, 

 a larger ratio is required. 



