CHAPTER VIII 

 THE SCALING OF DEFECTIVE LOGS 



88. Deductions from Scale for Unsound Defects. No deduction 

 will be made from the scale of a log unless there is some visible indica- 

 tion of unsound defect such as will reduce the quantity of sound lumber 

 that can be sawed from the log. The character and extent of the deduc- 

 tion to be made for the indicated defect is judged by the scaler based 

 on his knowledge of the given species and region and his experience in 

 observing the way such logs open up in sawing. Defects visible at the 

 ends of the log give a basis for judging the remaining contents. When 

 logs must be scaled as they lie after bucking, with ends still in contact, 

 as sometimes happens with overhead skidder operations, it is difficult 

 to make correct deductions for defects. 



The surface of the log offers additional evidence of unsound defects, 

 especially the character of the knots. Sound knots from live limbs 

 do not affect the scale, but the knots of dead stubs, if they show rot, 

 and especially the presence of rotten knot holes, with exudations of 

 pitch, indicate the presence of advanced stages of rot, which a little 

 experience in the mill will teach the scaler to allow for in full measure. 

 The mere suspicion that logs may be rotten does not justify deductions. 

 When timber is full of concealed defects with no surface indications, 

 the method of deducting a given per cent of the total scale may be 

 adopted instead of attempting to reduce the scale of each log separately. 



89. Methods of Making Deductions. There are four methods of 

 reducing the scale of a log; by length, by diameter, by diagram or 

 specific quantity of lumber and by a per cent of the gross scale. The 

 reduction in. either length or diameter enables the scaler to read the 

 reduced scale from his stick as for a log of smaller dimensions and is 

 the simplest form of discount, but least accurate except for certain 

 forms of defect. 



Reduction in Length. A reduction in length gives a proportionate 

 reduction in per cent of total contents. The per cent taken depends 

 on the relation between the lengths of the log before and after reduc- 

 tion. For a 16-foot log, 12J per cent of the total scale is deducted 

 for each 2-foot reduction. This deduction becomes 10 per cent for 

 a 20-foot log or 16f per cent for a 12-foot log. 



Reduction in Diameter. Reduction in diameter is not a satisfactory 

 method of making deductions except for rotten sap found on logs cut 



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