CHAPTER XIV 



VOLUME TABLES FOR PIECE PRODUCTS, COMBINATION 

 AND GRADED VOLUME TABLES 



162. Volume Tables for Piece Products. The purpose of volume 

 tables for piece products is identical with that for board feet — to enable 

 the timber estimator to dispense with the necessity of judging by eye 

 the contents of separate trees, and substituting therefor merely the 

 record of diameters and heights. 



Volume tables for piece products are limited in scope. The speci- 

 fications as to size of the product are the governing factor. For poles, 

 no volume table is needed. For small products such as staves, it is 

 almost impossible to make volume tables, on account of the effect of 

 cull in reducing the output and the difficulty of judging this in the 

 standing timber. Even here, tables showing the number of staves 

 of given dimensions in perfect trees of different diameters, or in sections 

 or bolts of different diameters may be of help in estimating. Here, 

 as elsewhere, the cull factor cannot be introduced into volume tables 

 but must be applied as a reduction factor to their contents. 



To construct a volume table for any specific product, the same 

 methods used in constructing log rules can be applied; first, the number 

 of pieces of certain dimensions which can be cut from logs or bolts of 

 given diameters can be found by plotting with cross-section of the 

 standard piece upon the areas of circles. Second, these theoretical 

 results can be checked against the actual number of pieces hewn or 

 sawed from logs or bolts of the same diameter. The second check 

 is to ascertain the effect of irregular shapes, and of methods of cutting 

 or manufacture, as affected by the grain of the wood and tools used. 

 In such a check, only sound logs are taken, but the factor of cull may 

 be studied at the same time. The contents of these logs can then be 

 combined into volume tables by the methods outlined in Chapter XL 



163. Volume Tables for Railroad Cross Ties. The most useful 

 volume tables for such products are those for railroad cross ties. Just 

 as for poles, the length of the ties, usually standardized at 8 feet, is 

 a partial indication of the number of ties which can be cut from trees 

 of given sizes. Hewn or pole ties, flattened on the faces only, are cut 

 only from trees or the upper portion of boles which are too small to 

 produce two or more ties from one bolt. Volume tables are needed : 



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