Effect of resaw on output of single band mills in southern hardwoods

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Title:
Effect of resaw on output of single band mills in southern hardwoods
Physical Description:
Mixed Material
Creator:
Garver, R. D
Miller, R. H
United States -- Forest Service
Forest Products Laboratory (U.S.)
University of Wisconsin
Publisher:
U.S. Dept. of Agriculture, Forest Service, Forest Products Laboratory ( Madison, Wis )
Publication Date:

Record Information

Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
aleph - 29347525
oclc - 756502939
System ID:
AA00020637:00001

Full Text
*


trItCT O1 PISAW oN IOUTIPUT oF SINCILI
IBAND MILLS IN SOUIITHEN hARIDWOD1S
May 1933




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UNITED STATES DEPARTMENT OF AGRICULTURE
FOREST SERVICE
FOREST PRODUCTS LABORATORY
Madison, Wisconsin
In Cooperation with the University of Wisconsin


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Digitized by the Internet Archive
in 2013









http://archive.org/detailIs/effect00unit






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R. D. GARVER, Senior Forester.
and R. K. LIILLER, Associate Enineer



Over one-third of a million board feet c' southern oiak lo:s a'
recently timed and tallied by the United States Forest Service tlrru:}
sawmills located in Louisiana, Tennessee, and Arkansas. Half of tC se
mills were equipped with a band and resaw, ani half had only a single ce n
saw. No quarter sawin1- was done duri-. the test, so thaIt the output frc m
each group of mills should be comparable, except as influenced '. t1e use
of a resaw. The' table gives the milling time per thousand board feet fr
each group cf mills, the relative output per hour, and the l-abor cost for
logs varying in size from 10 inches to 4o inches. Overrun is, shown for all
mills together, because there was no appreciable difference for the two
groups of mills.

For comparative pur-poses, the c2-inch diameter class may be taken
as an aver--,- for both groups of mills. The time required to saw a
thousand board feet of lumber from 22-inch logs for single band mills was
14.3 minutes, whereas in the band and resaw mills only 0S.- minutes was
necessary. Based on these time factors, the output for the first group
would be 4,196 board feet an hour and, for the second group, 7,147 borar
feet. Accordirg to these figures, the output of a single band mill -,- be
increased about 70 percent by the addition of a resaw. ,- time figures
are for actual operation; no delay time is included.

.o operate the single band mills, an aver,. c of 21 men were required
at a cost under present wage scales, f .33 cents a minute and, for the
band and resaw mills, 29 men at a cost of F cents a minute. Based cn these
costs and time figures, the single b-.r.l mills produced lumber at a mill
labor cost of 91 cents per thousand board feet, and the band and resaw,
mills at 67 cents per thousand board feet.

Summing up, the addition of a resaw to a single band mill increases
the output 70 percent, and results in a decreased mill labor cost of 20
percent, also a substantial reduction of overhead costs.





*Published in American Lumberman, 27, 1)33.


R1245









Output of single band and single band and resa' mills whlen cutting
southern oak_ logs of different sizes


Diameter:Overrunk1' for: killingg time per I Output per hour : ill labor cost
inside all mills : (lumber tally)3 (lumber tally)_ p-er 2 (lu..or
bark : (net log :tall)
:scale basis):Single : Single :Single : Band avd:Sin-le : Sin le
S: band band and: band : resaw band : band and
.resaw : .: re aw


Inches : Percent


.~ir~utes


: Board feet


50. 8
44.
31.5
21.0
12.5
5.5
2.0

1.0

-.5
-1.0
-1.5
-1.5
-2.0
-2.0
-2.5


30.3
21.7
17.9
lo.l
15.3
14.7
14.3

13.9
13.5
13.5
13.5
13.S
14.5
15.3
16.2


10
12
14
16
18
20
22

24 :
26
28
30
32
34
36
38
4o


25. 1,943
17.0 :2 ,765
12.3 : 3,352
99 3,727
S.7 : 3 0L
oLL
.5 : 0 2
s.4 14,1,

8.3 : 4,317
8.2 :4444
8.1 L44, 4L
g.o0 : 4,444
7. n 4,34s
S.0 4,138
.4 :3,922
9.2 : 3,704
10.2 : ) 3,4-s


2,353 $1.95
3,59 : 1.37
k, -7-- : 1.13
1.13
-,0 : 1.02
7,059 .93
7,143 : .91

7,22 .8
7,317 : 5
7,407 : .5
7,500 .5
7,59' ., 7
7,5 00 .92
7,143 : .97
6,522 : 1.03
5,82 1.09


-Includes the following oaks: overcrup, cherrybark, willow, lowland blacL.:,
nuttall, and pin.
-Based on Scribner Decimal C Log Rule and green lumber tally.
Actual ru-' r.iri time.
-4Green lumber tally.


R1245


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