A certain amount of avoidable waste occurs in the handling of green veneer 
from the lathe to the clipper. In large operations where it is possible to 
handle the green veneer mechanically through automatic clippers the utiliza- 
tion is at its best, for tears in the veneer do not commonly occur and si:. 
sheets are clipped to best advantage so as to eliminate defects. The mini. 
width of veneer clipped by present-day automatic clippers is 2 inches. This 
.minimum results in a certain amount of waste, since many defects could be 
liminated by clipping out only a 1-inch width. In smaller operations where 
expensive automatic conveying and clipping equipment is not justified, the 
veneer is often torn into sheets and then clipped to standard widths in 
multiple. This results in a certain amount of waste at each tear, in the 
introduction of additional splits because of manual handling, and in sheets 
that are not clipped to best advantage from the standpoint of elimin-.ting 
defects. A method of winding the green veneer on reels directly from the 
lathe, which is now used to some extent in hardwood plants, is one that 
can be used in smaller plants to reduce veneer v/aste. Clipping sheets singly 
to random widths so as to eliminate defects, even if manual handling is 
necessary, is a practice that will reduce waste because it results in a 
higher percentage of high quality veneer. 
A practice that is doubly wasteful is the clipping of veneer from spiral- 
grained or interlocked-grained woods without regard for grain direction. 
When veneer of such woods is torn at the lathe into sheets for handling and 
then clipped pe^-pendicular to the ends, lar^e^tri angular sections are 
inevitably clipped at each tear and are wasted. Furthermore, the grain 
direction of the clipped sheets is not perpendicular to the edges and plywood 
made from such veneer usually warps. If, on the other hand, the veneer is 
clipped along the grain direction and then squared by trimming at the ends, 
the quality of the veneer is improved and the amount of waste incurred in 
producing it is reduced, especially if the veneer is clipped to fairly narrow 
pieces. When green veneer is handled on reels, it is easy to provide for 
setting the reel at an angle to the clipper knife so that veneer cut from 
s;.iral-grained bolts is clipped parallel to the grain. 
The process of drying veneer sometimes results in waste because of degrade 
that occurs in the form of splitting, honeycombing (in thick veneers), and 
buckling (especially at ends). When veneer is dried in a kiln, special pre- 
cautions should be taken to ile it so that it is free to shrink during 
drying. If this is not done many of the veneer sheets may split. In all 
types of vt.nccr driers it is necessary to use drying schedules adapted to the 
type of veneer being dried so as to avoid degrade during drying. The storage 
of dry veneer, its subsequent handling, and its redrying may result in 
further losses, many of which can be reduced. It is sometimes desirable to 
store veneer and veneered products in humidity-controlled rooms to prevent 
development of defects related to dimensional changes that occur with changes 
in humidity. The adequate control of humidity in plants and in storage sheds 
is not difficult. Z 
7 
Forest Products Laboratory Reports Nos. P.1140 and R1612. 
ort Ho. R1666-4 -4- 
