UTILIZATION OF BLACK WALNUT. 



51 



Table 19.- 



-Average width of sapwood and diameter of heartwood, of walnut 

 logs of different diameters. 



Diameter inside bark. 



Single 



width of 



sap. 



Diameter 

 of heart. 



Diameter inside bark. 



Single 



width of 



sap. 



Diameter 

 of heart. 



Inches. 

 6. 



Inches. 

 0.8 



Inches. 



4.4 



5.4 



6.2 



7.0 



8.0 



8.8 



9.6 



10.6 



11.4 



12.2 



13.2- 



14.0 



15.0 



| 



Inches. 

 19 



Inhes. 

 1.6 

 1.7 

 1.7 

 1.8 

 1.8 

 1.8 

 1.9 

 1.9 

 1.9 

 2.0 

 2.0 

 2.0 



Inches. 

 15.8 



7 



1 

 1 

 1 

 1 

 1 

 1 

 1 

 1 

 1 

 1 



8 

 9 

 

 

 1 

 o 

 2 

 3 

 4 

 4 

 5 

 <=, 



20 



16.6 



8 



21 



17.6 



9 



22 



18.4 



10 



23 



19.4 



11 



24 



20.4 



12 



25 



21.2 



13 



26 



22.2 



14... 



27 



23.2 



15 



28 



24.0 



16 



29 



25.0 



17 



30 



26.0 



18 















If the straight rotary process is employed, manufacturers generally 

 find that there is, on the average, about 20 per cent of waste, not 

 counting the core and the sapwood. Figuring the core at 6 inches 

 in diameter for an average log of 18 inches in diameter, because 

 rotary logs generally run small, and figuring 2 inches as the thick- 

 ness of the sapwood, the entire log contains 359 square feet of veneer 

 to the linear foot of log, inside the sapwood, less 66 square feet in 

 the core, which is generally considered waste, thus leaving 293 square 

 feet to the linear foot. If 20 per cent waste in slicing is deducted, 

 a net yield is left of 235 square feet of veneer to the linear foot. As 

 the original log scaled 12 feet to the linear foot, this makes a yield 

 of about 19^ square feet of veneer to the board foot of log, log scale. 



In the stay-log rotary process, a half log from a log 24 inches 

 in diameter, which is representative for this type of veneering, will 

 yield to the linear foot, if it is perfectly clear, about 273 square feet 

 of one twenty-eighth-inch heartwood veneer cut from the sapwood 

 side, and about 282 square feet cut from the heartwood side, allowing 

 for a 3-inch " dog board " and the waste in cutting down to get a 

 sufficiently wide sheet of heartwood veneer. Figure 7 shows the 

 cross-sectional area from which merchantable veneer is generally 

 cut by the two processes. Manufacturers calculate that there is a 

 10 per cent waste in the portion from which merchantable veneer is 

 cut. If this 10 per cent is deducted, a balance is left of 246 and 254 

 square feet, respectively, in cutting from the sapwood and heart- 

 wood sides. 



As there are 12^ board feet, log scale, for each foot in length in 

 the half log referred to above, this makes a yield of approximately 

 20 square feet of veneer for each board foot, log scale. This figure 

 corresponds with the general average of 20 obtained from reports of 

 veneer manufacturers. 



