26 



Hardwood Record — Veneer & Panel Section 



September 25, 1919 



flitch — that is, not edged. The flitch is more valuable 

 because a swell on the flitch will often go into the butt of 

 the stock and make a gunstock which would have been 

 lost by edging. (Figure 2.) 



By comparing the utilization of different mills it was 

 determined to what point the production of propeller stock 

 could be increased without increasing greatly the waste. 

 The best utilization was found to yield approximately the 

 following proportions of material: propeller lumber, 15 

 per cent; gunstock flitch, 70 per cent; waste in the form 

 of common boards, 1 5 per cent. These were about the 

 average proportions being manufactured at the time of 

 the signing of the armistice. The percentages, of course, 

 differ with the size and quality of logs. 



With this information it could be determined whether 

 a particular mill was practicing the best utilization. Each 

 mill has its own peculiar problems, however, which must 

 be taken into consideration. 



Classification of Logs 



For securing the best utilization for war uses walnut 

 logs are divided into two clases, airplane logs which saw 

 out large amounts of propeller stock, and gunstock logs 

 from which only a small proportion of propeller lumber 

 can be manufactured. Smooth logs I 6 inches and over in 

 diameter at the small end are generally considered as air- 

 plane logs, while rough logs and logs under 1 6 inches are 

 classed as gunstock logs. However, some gunstock flitch 

 is secured from most logs and propeller stock is cut from 

 the better grade of gunstock logs. Naturally each of 

 these tw^o classes of logs presents a different utilization 

 problem. 



The manufacturer could get the greatest profit from 

 propeller logs by ignoring gunstock material and sawing 

 on four sides of the log in violation of the War Department 

 regulation and in spite of the greater amount of waste 

 involved. It was found that a better financial return 

 could be secured by sawing a high percentage of gunstock 

 flitch from the gunstock logs than by cutting the maximum 



amount of high-priced propeller stock from them. This 

 was due to the high percentage of low-priced waste in- 

 volved in getting all available propeller stock from such 

 logs. 



The following tables show the approximate proportion 

 of different products sawed from these two types of logs 

 and the value of the different products obtained per thou- 

 sand board feet. They show that the greater amount of 

 propeller stock produced, the greater the waste in common 

 lumber; also that the greater the proportion of flitch cut 

 from gunstock logs and propeller lumber from propeller 

 logs, the greater the value per thousand feet of the differ- 

 ent products. 



These tables do not show the profit obtained by the 

 manufacturers, since the cost of the logs, cost of manufac- 

 ture, and actual yield v/hen sawed by different methods 

 would have to be taken into consideration to determine 



this. 



Table 1 



Average Proportions of Propeller Stock, Gunstock Flitch and Com- 

 mon Lumber Sawed from Two Types of Walnut Logs. 

 Type 1. 1 5-in. diameter fairly smooth log ("Gunstock Log") . 



(g) log cut on four sides. 



Specifications 



The specifications for propeller stock call for reason- 

 ably straight grain, since cross-grained wood is deficient 

 in strength. The mills as a rule sawed the logs in a line 

 parallel to the surface instead of to the central axis of the 

 log, which left a wedge-shaped piece in the form of waste 



TABLE 2 

 Proportionate Amounts of Propeller Stock, Gunstock Flitch, and Common Lumber and Values Per 1,000 Board Feed Sawed from 



Walnut. 

 Type 1. 1 5 in. diameter fairly smooth log ("Gunstock Log") 

 Gunstock Flitch 



Value 

 ($1 Per 

 Gunstock 

 Amount Blank) 



850 ft. @ $143 per M ft. ( 7 ft. per blank) = $121.55 

 700 ft. @ I 1 1 per M ft. ( 9 ft. per blank) = 77.70 

 600 ft. @ 100 per M ft. (10 ft. per blank) = 60.00 

 200 ft. @ 67 per M ft. (15 ft. per blank) -- 13.40 



Common Lumber 



Amount Value 



($20 per M Ft.) 



150 ft. - $ 3 



200 ft. - 4 



250 ft. -- 5 



550 ft. = II 



Total 

 Value Per 



1,000 Ft. 



$124.55 



1 11.70 



110.00 



99.40 



All cuts parallel. 



Type 2. 18 in. diameter smooth log ("Propeller Log*') 

 Gunstock Flitch 



Amount 



450 ft. (a) $1 11 per M ft. ( 9 ft. per blank) 



300 ft. @ 1 00 per M it. (10 ft. per blank) 



I 00 ft. @ 80 per M ft. (12 ft. per blank) 



(e), (f) all cuts parallel, 

 (g) log cut on four sides. 



