KILN DRYING HANDBOOK. 
41 
WALNUT GUNSTOCKS. 
Walnut for gunstocks is usually cut in the form of rough blanks, 
steamed to darken the sapwood, and then shipped to the gunmaker 
for drying. All stocks to be kiln dried should be end dipped in 
hot pitch before loading into the kiln. A schedule that has been 
used successfully in the drying of many thousand blanks is given 
in Table 12. 
MAPLE SHOE LAST BLOCKS. 
Maple shoe-last blocks, end clipped and piled on stickers, can be 
dried successfully under hardwood schedule 7. 
PENCIL CEDAR. 
Pencil cedar, the southern juniper used for pencils and cedar 
chests, is quite difficult to dry and care must be used to prevent 
the shelling off of the streaks of sapwood which will result from 
too steep a moisture gradient and too severe casehardening. A 
special schedule (Table 13) has been prepared for the drying of 
1-inch boards of this species; it covers about the same range as 
hardwood schedule 3. 
The cedar oil present in this wood causes a variable error in 
making moisture determinations, since it is driven off with the 
moisture in the drying oven, resulting in a calculated moisture con- 
tent higher than the actual. This error is usually not more than 
2 or 3 per cent, though it may be as great as 5 per cent. 
Table 12. — Drying schedule for black ivalnut gunstock blanks. 
Moisture 
content. 
Dry bulb. 
Wet bulb. 
Relative 
humidity. 
Per cent. 
°F. 
°F. 
Per cent. 
Initial. 
110 
102 
75 
35 
113 
102 
68 
20 
115 
104 
87 
15 
117 
103 
62 
10 
130 
105 
43 
8 to final. 
140 
107 
34 
Table 13. — Drying schedule for 1-inch pencil cedar. 
Moisture 
content 
(heart 
Dry bulb. 
Wet bulb. 
Relative 
humidity. 
samples). 
Per cent. 
°F. 
°F. 
Per cent. 
Initial. 
140 
128 
70 
20 
150 
127 
50 
15 
155 
124 
40 
10 to final. 
>* 
115 
25 
PLYWOOD PANELS. 
The drying of plywood panels is a special problem in which sim- 
plicity of control and operation are important. Panels can be dried 
successfully under widely varying conditions of temperature and 
