b.^i ywstii-t* ^pf ■*#?'. '_ S'*- -c SJ J , FOREST PRODUCTS LABORATORY t FOREST SEP' U. S. DEPARTMENT OF AGRICULTURE M5 SMALL SAWMILL IMPROVEMENT PRACTICAL POINTERS TO FIELD AGENCIES SHORT-CUT METHOD OF FUSING TH5 \:i':. Y .: '.;. SIZSD TRE5 THAT PAYS IIS WAY through smai sawuill OPERATIONS Sawmill operators realize that losses may result from taking small trees, but as a rule they or local forest-extension agencies are not eouipped to make the detailed study required to determine the minimum size of tree which pays its way. A short-cut method for obtaining tne "break even" DBH for small mills is given here in which the mill and yard labor costs alone furnish the necessary information as to the influence of tree size on costs. The results obtained by this method agree fairly closely with those found by detailed mill-scale stud- ies. AH other costs are taken as a constant and added to tne mill and yard labor costs by tree DBH's. The costs and values in dollars are then plotted against the DBH. The intersection of the total cost line with the total value line gives the "break even Ti point. (see example, page 3)» This intersection will usually be found in the lower ten DBH classes milled so that mill labor costs and values need be determined only for tne ten smaller DBH clashes. Three men in four operating days can get the required time and cost information from which conclusions can be deduced in a few hours of office computations. To apply this method in the field requires: (1) The cost per U board feet, lumber tally, for stum- (2) The average costs per M board feet exclus labor costs. (3) The milling and yard labor cost per M bog smaller DBH classes. (k) The value per M board feet, lumber tally, series of sizes included in (3). (1) To get the cost of stumpage: (a) When timber is bought on a lumber tally basis, use the contract price per ]J[ board feet. (b) When timber is bought on a lump sum basis, divide the purchase price by the estimated number of 1,1 board feet, lumber ti , i lil be cut. HS99-13 tMaintained at Madison, Wisconsin in cooperation with the University of Wisconsin. *See outline in Small Sawmill Improvement Working Plan, March 1930, for explanation of indexing system proposed •s (c) When timber is bought on a log scale basis, go to the fell area of the major producer and mark on each lor; the tree DBH for all trues in the lower ten DBH classes. When these marked logs are scaled at the mill, record the total scale by DBH classes. If logs are graded, also record grade, prom this compute the total cost of the log scale footage in each DB ; class. This total cost per DBH class divided by the lumber tally per DE ;lass gives the stumpage cost per 1.1 board feet lumber tally. (2) The total costs, exclusive of stumpage and mill labor, will vary <*H the method of buying timber. If timber is bought on a lumber tally basis ( • or on a lump sum basis (lb), the total costs include all logging, transporta- tion, mill moving, maintenance, depreciation, taxes, selling, ond supervision costs. If timber is bought on a log scale basis at tne mill (lc) , total costs, excluding mill and yard labor, include mill moving, maintenance, depreciation, taxes, selling, and supervision. These total costs are arrived at from records supplemented if necessary with estimates. (3) T° get the milling and yard labor cost per U board feet lumber tally by DBH classes: One man at the felling area marks on each log the tree DBH from which it is cut for all trees cut in the lower ten DBH classes. No log diameters need to be taken. One man at the mill gets the headsaw time required for each marked lc ■ Starting time begins when the emoty carriage stops to receive the log.. It should be taken v/ith a stop watch to the nearest 0.05 minute. The time for each log is recorded under its proper DBH class. This man should also get ■■ record of all delays during paid time when not sawing for a period of several days. This delay time is totaled, and from it the percentage of nonproductive time is determined. The recorded total time for each DEE class is increased by the amount of this delay time. A second man at the mill tallies and grades the product from each marked log, entering footage and grade under the DBH class of the tree from which the log v/as cut. The grades are those upon which the lumber is sold b; o r- ator. If any quantity discount from the green tally is applied by the pur- chaser of the lumber, this must be applied to the tally credited to the mill. The total time for each D3H class divided by the total tally for < : DBH class gives milling time per U board feet for the respective DBH classes chosen. This information is plotted and converted to labor costs by cha - the labor cost per hour of milling. (h) To get the value per U board feet, lumber tally, multiply the foots in each grade within a DBH class by the value received for t] r s] ctiv grades, change to value r r U board feet by dividing the total value within the DBH class by the amount in '.; board feet, and plot the i s of v X899-13 -2- c Using the labor cost per M board feet lumber tally as found in (3) as a base, add the stumpage value as found in (1) and the average; cost exclusive of mill and yard labor cost found in (2) to build up a total cost curve for the smaller DBH classes chosen. Transfer the values as read fron the curve for corresponding DBH classes found in (4) , and the intersection is taken as the "break even" 2r. : - Theoretically, this method is open to criticism because all costs, • mill labor costs, are taken as a constant uninfluenced by treo size. In • check based upon more detailed logging and mill scale studies this metho . the same "break even" DBH in five instances, in ten instances it was one inc different, and in one instance two inches. In usin-r this method, distortion of the "break even" DBH r:ill result from inaccurate analysis of costs other than mill and yard labor, inaccurate esti- n^tes of the lumber tally of standing timber (lb) , and the omission of any lors marked for the sample. It is reco^nv-.nded only as a. relatively cheap method of finding the "break even" DBH on small o- ■ .- I ic- ■ rough luml r. planer operations should not be included. 20 S o — 6 TYPiCAL EXAMPLE OF COST AND VALUE CURVES £2^PERJ1,B.F. "BREAK EVEN"D.3.H. COSTS OTHER THAM MILL AND YARD LABOR M/t Land ^L^IoRjorrs „ 9 _ -1 I L L 10 II II IS 14 IS 16 DIAMETER BREAST Hl$H (INCHED ± II J 18 u. j*p««7 r > c , . The following forms are suggested as guides in recording fi( . preview of the snecific operation should D and modifications in se tions incorporated to conform with the objective of [letting data separat the volume in each value group dealt in by the operator. Form for 1(c) Log Scale Diameter breast high Grade I Grade II Le ::: Inches 9 10 11 12 e t c • Prices per U board feet log scale: Grade I Grade II Grade III For each diameter class multiply the total log scale (!,' board feet) in each log grade by price paid per U board feet. The re- sultant total price paid divided by the footage (I: board feet) for the DBH class in the lumber tally sheet is the value per U board feet lumber tally. Diameter breast high Form for milling time (3) Sawing time reouired Inches 10 11 12 etd Number of men in crew and wage per hour! Delay time Date Interval covered or total time Delay time within interval Record to the nearest 0.05 minute the headsaw tin quired for each marked log in the DBH class from which the log originated. RS99-13 •4- / Digitized by the Internet Archive ( in 2013 http://archive.org/details/shortcutfOOfore SOFTWOOD TALLY S Diameter breast high, 9 inches : 4/4-inch thickness :: g/4-inch thickness :B&Btr.:No. 10: No. 2C:No. 30: :3 & Btr. :No. lG:: r o. 20: No. 7 ,C Width Length 3 : b : S : : : : 14 : lb 4 : 6 : o 10 14 : lb 5 b 10 14 lb 6 : 6 ! 8 10 14 : lb : g : 6 : g : 10 : 14 : 16 : 10 : b : g : 10 : 14 : lb : 12 : 6 : g : 10 : 14 i 16 : Use a separate sheet for each D3H class. Use the grade groups under which sales are made for the study oceration. Based on these entries of number of pieces of specified thickness, width, and length compute footage in each -:rade, multiply the number of I! board feet by the i • ■ r '.'. board feet for the grade, total resultant values for all grades, and divide by the nu ! r of M board feet in the DBH class to get value i er 1,1 board feet for RS99-13 •5- HAEDWCCD TALLY SHE Diameter breast high, 12 inches Surface measure by grade ?. A- S» : No. 1 common : No. 2 Common Thickness No. 3 Common U/4 White Oak 12 Ul Ties, timbers, and special items by grades and sizes Red Oak 4/4 6/4 8/4 Ties, timbers, and special items by grades and sizes. Basswood 4/4 b/4 8/4 Special items by grades and sizes, Miscellaneous Special items by grades and sizes. Use a separate tally sheet for each LBH class. Use a hardwood lumber tally stick to get the surface measure and enter surface measure footage under proper division as to species, thickness, and grade. Hardwood lumber tally sticks are available that either show the actual surface feet or the surface feet discounted for drying shrinkage. Use the former. When lumber is sold green, use full tally; if sold dry, discount full tally. Convert surface measure as tallied to board foot measure and get composite value per M board feet as described for softwood. Contributed by C- J« ~ Lford, yorest Products Laboratory, October 1940. H899-13 _c UNIVERSITY OF FLORID* fill III 'JnSs" 08926 8998 (