•Square
foot 3/8 inch basis
•Square
meter, 1 mm basis
•Imperial
to metric conversion factors
• Veneer
sheet thickness
•Veneer
sheet width
•Veneer
sheet length
•Plywood
panel sizes
•Volume
of veneer or panels
1. Converting
surface measure of any thickness to the 3/8 inch basis
2. Cubic
foot calculation
3. Cubic
meter calculation
•Veneer
sizes
•Plywood
panel sizes
•Volume
of veneer or panels
•From
mill studies
•Theoretical
material balance
•Cubic
recovery ratio (CCR)
•Veneer
recovery factor (VRF)
•Relationship
between CRR and VRF
•Veneer
recovery and board foot log scale
Chapter 5. Veneer and Plywood

Measurement
Standard Reporting Basis
Square Foot 3/8 Inch Basis (SF_{3/8}).
In North America, statistics on veneer, plywood, and other panel
products (Chapter 6) are generally reported as the number of square
feet, or surface measure, of a stated thickness. Due to the variety
of thicknesses available, surface measures are not directly comparable.
Hence to facilitate accounting and reporting, statistics are commonly
expressed on a standardized thickness basis. For veneer and plywood,
this standard thickness basis is 3/8 inch. Plywood and veneer volumes
are usually measured dry (2 to 5% MC_{od}).
For other panel products, covered in Chapter 6, the standard thickness
basis may be 1/8, 3/8, 1/2, or 3/4 inch depending on the category
of panel. Table 51 lists a number of common panel thicknesses and
factors to convert them to one of the four standard thickness bases.
Square Meter, 1 mm Basis. The standard
basis for reporting plywood and veneer in countries on the metric
system is the square meter, 1 mm basis. This represents a piece 1
m square and 1 mm thick, or 1/1,000 cubic meter.
Imperial to Metric Conversion Factors for Plywood.
Table 52 presents commonly used conversions.
U.S. Softwood Veneer and Plywood
Veneer Sheet Thickness. Softwood
veneer thicknesses usually range from 1/16 to 5/16 inch, with the
most common being 1/10, 1/8, and 1/6 inch. Thicknesses are often
expressed by mills in thousandths of an inch. The lathe setting
is somewhat larger to account for compression during peeling, peeling
variation, and shrinkage during drying. Procedures to calculate
the green target thickness at the lathe are similar to those for
lumber explained in Chapter 4 (pp. 5859).
Veneer Sheet Width. Assuming the
common 4 foot plywood panel width, veneer is manufactured in the
following nominal widths: 48 inches (full), 24 inches (half), and
strip (narrow strips above a minimum salvage size, often 6 inches).
Other widths may be produced to correspond to other panel sizes,
as shown in Table 53. To allow for shrinkage of veneer during drying
and trimming of finished plywood panels, these widths are increased
to develop target values on machinery. Thus a mill's green clipper
may produce full and half widths as 54 and 27 inches respectively.
Actual practice will vary from mill to mill based on quality control
and other factors.
Veneer Sheet Length. When veneer
is obtained from a lathe, veneer length exceeds that of a finished
plywood panel. For example, on the common 8 foot lathe, the veneer
is initially about 100 to 104 inches long. This oversize length
allows for shrinkage when the veneer is dried and for panel trimming.
The actual log (block) peeled is somewhat longer than the length
of veneer. Veneer lengths correspond to panel lengths shown in Table
53. The most common length is 96 inches (8 foot plywood). Crossband
widths are half that length. The lineal footage of the veneer ribbon
produced from a lathe can be estimated by dividing the square footage
by the veneer length.
Plywood Panel Sizes. Table 53
presents the dimensions of softwood plywood according to U.S. Product
Standard PS 183. The most commonly produced panel size is 4 by
8 feet in various thicknesses.
Volume of Veneer or Panels:
1. Converting Surface Measure of Any Thickness
to the 3/8 Inch Basis. To convert surface measure of veneer
or plywood of some thickness (SM_{t}) to the 3/8 inch basis (see Example 1), divide the actual
thickness (t) in inches by 3/8 inch (t / 0.375 inch) and multiply
by the surface measure:
SF_{3/8}= SM_{t}
_{*} (t / 0.375) = 2.667 _{*} t _{*} SM_{t}.
Column 4 of Table 51 lists values of t/0.375.
Veneer is marketed on the basis of nominal dimensions;
the square footage of 1/10 inch full sheets is generally calculated
on the basis of nominal dimensions such as 4 by 8 feet and excludes
the oversizing required for trim and shrinkage. To estimate the
total wood fiber represented, increase the square footage by about
12% (Fahey 1987) or measure a sample of sheets and calculate the
adjustment factor needed.
Table
51. Conversion of actual panel thickness to
standard thickness basis.
_{Actual
Thickness}


^{Conversion
to}










(in)

(mm)


1/8 inch basis

3/8 inch basis

1/2 inch basis

3/4 inch basis



(1)

(2)


(3)

(4)

(5)

(6)


1/8

3.18


1.0000

0.3333

0.2500

0.1667


3/16

4.76


1.5000

0.5000

0.3750

0.2500


1/4

6.35


2.0000

0.6667

0.5000

0.3333


5/16

7.94


2.5000

0.8333

0.6250

0.4167










3/8

9.53


3.0000

1.0000

0.7500

0.5000


7/16

11.11


3.5000

1.1667

0.8750

0.5833


1/2

12.70


4.0000

1.3333

1.0000

0.6667


9/16

14.29


4.5000

1.5000

1.1250

0.7500


5/8

15.88


5.0000

1.6667

1.2500

0.8333










11/16

17.46


5.5000

1.8333

1.3750

0.9167


3/4

19.05


6.0000

2.0000

1.5000

1.0000


13/16

20.64


6.5000

2.1667

1.6250

1.0833


7/8

22.23


7.0000

2.3333

1.7500

1.1667


15/16

23.81


7.5000

2.5000

1.8750

1.2500










1

25.40


8.0000

2.6667

2.0000

1.3333


11/16

26.99


8.5000

2.8333

2.1250

1.4167


11/8

28.58


9.0000

3.0000

2.2500

1.5000


13/16

30.16


9.5000

3.1667

2.3750

1.5833


11/4

31.75


10.0000

3.3333

2.5000

1.6667


















Source: Calculated
by the author.
Table
52. Imperialmetric conversion factors for plywood.
From / To:

SF,
3/8

m^{2},
1 mm

MSF, 3/8

1,000 m^{2},
1 mm

ft^{3}

m^{3}


SF,
3/8

1

0.885

0.001

0.000885

0.03125

0.000885

m^{2},
1 mm

1.130

1

0.001130

0.001

0.035315

0.001

MSF,
3/8

1,000

885

1

0.885

31.25

0.885

1,000
m^{2}, 1 mm

1,130

1,000

1.130

1

35.315

1

ft^{3}

32

28.318

0.032

0.0283

1

0.0283

m^{3}

1,130

1,000

1.130

1

35.315

1

Source: Calculated
by the author.
Note: The
values in the rows for 1,000 m^{2}, 1 mm basis and for
m^{3} are identical since a 1,000 m^{2} area that
is 1 mm thick represents 1 m^{3} of volume.
2. Cubic Foot Calculation.
The volume, in cubic feet, of a single 4 by 8 foot panel of
thickness t inches is
ft^{3} = (4 _{*} 8 feet) _{*} t / 12
= 32 _{*} t / 12.
Hence the volume of a 1/2 inch thick panel is 1.3333 cubic feet.
Substituting other thicknesses results in column 2 of Table 54.
When the 3/8 inch thickness is substituted into this formula,
the volume of a 4 by 8 foot panel is exactly one cubic foot. In
general, the formula to convert the SF _{3/8}equivalent of any
panel thickness to cubic feet is
ft^{3} = SF_{3/8 * }(3/8) / 12
= SF_{3/8}/ 32.
In section 1 above, it was found that 1,500 square feet
of 1/2 inch plywood was equivalent to 2,000 square feet on the 3/8
basis. Substituting this into the above formula results in an equivalent
of 62.5 cubic feet of plywood. If the formula in section 1, which
converts surface measure of any thickness to the 3/8 basis, is substituted
for SF _{3/8}, the following general relationship is found
ft^{3} = [SM_{t} _{*} (t / 0.375)] / 32
= SM_{t
* }t / 12
= 0.08333 _{*}
t _{*} SM_{t}.
This formula directly converts the square footage of any original
thickness to cubic feet equivalent. Values of 0.08333 _{*}
t are tabulated in column 3 of Table 54. The values in column 3
can also be obtained by dividing the cubic foot volume of a 4 by
8 foot panel of given thickness (column 2) by 32 square feet per
panel. With this calculation, column 3 can be interpreted as the
number of cubic feet of panel per square foot of panel of the indicated
thickness. See Example 2.
Since 1,000 square feet (MSF) is a common unit, column 4
reexpresses column 3 in cubic feet per MSF and column 5 converts
cubic feet per MSF to cubic meters per MSF. For example, Table 54
shows that 1,000 square feet of 3/8 inch plywood is equivalent to
31.25 cubic feet or 0.89 cubic meters. Reciprocals of these values
indicate that, for 3/8 inch plywood, there are 0.032 MSF (32.0 square
feet) per cubic foot and 1.124 MSF (1,124 square feet) per cubic
meter.
These formulas and methods can be used to obtain the cubic
foot volume of finished panels or nominally measured veneer. To
determine the cubic foot volume of green veneer needed to make the
panel, increase the result by 12% to account for layup and trim
losses (Fahey 1987).
3. Cubic Meter Calculation. Outside
North America, veneer and plywood are produced in metric sizes:
width (W) and length (L) in meters, thickness (t) in millimeters.
Statistics are normally reported in square meters surface measure
(on a 1 mm basis) or cubic meters. Formulas are
SM_{t }= L _{*}
W = surface measure, m^{2}, of original thickness.
SM_{1 }= SM_{t }_{*}t
= surface measure, m^{2},
1 mm basis.
m^{3 }= SM_{t}_{*} t / 1,000 = SM_{1
}/ 1,000.
To convert 1,500 square feet of 1/2 inch panels to 3/8
inch basis:
SF_{3/8}
= 1,500 _{*} (0.5 inch / 0.375 inch).
= 1,500
_{*} 1.3333 = 2,000 square feet.
The value 1.3333 is also found in Table 51, column
4, corresponding to 1/2 inch thickness.
To convert 1,000 square feet of 1/10 inch veneer to 3/8
inch basis:
SF_{3/8} =
1,000 _{* }(0.1 inch / 0.375 inch) = 267 square feet.
To convert 1,500 square feet of 1/2 inch plywood:
to the 3/8 basis
Multiply 1,500 by 1.3333
(column 4, Table 51) to get 2,000 ft^{2}3/8. This is the same result obtained
by the formula in section 1 (and Example 1).
to cubic feet (four equivalent
calculations are shown)
. ft^{3} =
SF_{3/8}_{ * }32
= 2,000 / 32 = 62.5.
. ft^{3} =
0.08333 _{* }SM_{t} _{* }t = 0.08333
_{* }1,500 _{*} 1/2 = 62.5.
. Multiply 1,500 by 0.0417
(column 3, Table 54)
to get
62.5.
. Multiply 1.5 MSF by 41.7
(column 4, Table 54)
to get
62.5.
to cubic meters
Multiply 1.5 MSF by 1.18 (column 5, Table 54)
to get 1.77.
Table 53. Softwood
plywood panel sizes.
Width

36, 48, 60 inches


Length

60 to 144 inches in 12 inch increments


Thickness sanded

1/4 to 11/4 inches in 1/8 inch
increments


Unsanded

5/16 to 11/4 inches in 1/8
inch increments over 3/8 inch


Tolerances sanded

±
1/64 inch for thicknesses ≤ 3/4 inch



±
3% for thicknesses > 3/4 inch


Unsanded

±
1/32 inch for thicknesses ≤ 13/16 inch



± 5% for thicknesses > 13/16 inch



Source: USDC
(1983a).
Note: Panel
thickness is measured at 9% MC_{od}. Panel sizes other
than those specified are available on special order.
Table 54. Standard plywood thickness with conversions
to cubic volume.

Panel thickness

4 by 8 foot
panel volume

ft^{3}of
panel


1,000 ft^{2} (MSF)
becomes



(inch)

(ft^{3})

perft^{2}of
panel


(ft^{3})

(m^{3})




(1)

(2)

(3)


(4)

(5)



1/8

0.3333

0.01042


10.42

0.29



3/16

0.5000

0.01562


15.62

0.44



1/4

0.6667

0.02083


20.83

0.59



5/16

0.8333

0.02604


26.04

0.74











3/8

1.0000

0.03125


31.25

0.89



7/16

1.1667

0.03646


36.46

1.03



1/2

1.3333

0.04166


41.66

1.18



9/16

1.5000

0.04688


46.88

1.33



5/8

1.6667

0.05208


52.08

1.48











11/16

1.8333

0.05729


57.29

1.62



3/4

2.0000

0.06250


62.50

1.77



13/16

2.1667

0.06771


67.71

1.92



7/8

2.3333

0.07292


72.92

2.06



15/16

2.5000

0.07812


78.12

2.21











1

2.6667

0.08333


83.33

2.36



11/16

2.8333

0.08854


88.54

2.51



11/8

3.0000

0.09375


93.75

2.65



13/16

3.1667

0.09896


98.96

2.80



11/4

3.3333

0.10416


104.16

2.95












Source: Calculated
by the author.
Hardwood Veneer and Plywood
Hardwood plywood is similar to
softwood plywood. The main differences in North America are that
hardwood plywood is more typically produced for appearance uses,
thus affecting the sizes of veneers and panels, and it is more
common to find hardwood "plywood" where materials other
than veneer (particleboard, hardboard, etc.) are used as core
stock.
Veneer Sizes. Hardwood veneers are
produced in a variety of ways. While softwood veneer is predominantly
rotary cut from logs, hardwood veneer may be rotary cut or sliced.
Usual slicing options are plain cut, quarter cut, half round, or
rift cut. Each of these cutting patterns produces a unique grain
pattern in the veneer. The raw material for slicing is commonly
a flitch sawn from a log in such a way as to expose one of the desired
grain patterns. Veneer is manufactured in thicknesses ranging from
1/50 to 1/4 of an inch, though on special order it can range from
1/200 to 1/2 inch. An average value to use would be either 1/16
or 1/32 inch, with 1/16 being the average of maximum and minimum
thicknesses across the industry. Specifications and terminology
for hardwood and decorative plywood are described in Product Standard
PS 5171 (USDC 1971). The standard specifies only the maximum thickness
of veneer, which varies depending on species category and plywood
type. The range of maximum standard thicknesses is from 1/12 to
1/4 inch.
Flitches may be random length but often are in whole foot
increments. Flitches may also include some of the round curvature
of the log, so each slice of veneer from a flitch may be of a different
width. Slices are trimmed to have parallel edges. Slices from a
flitch may be random width or trimmed to a uniform width. Customs
for manufacture of veneer differ between North America and overseas
producers.
Plywood Panel Sizes. Hardwood
plywood is more of a speciality product than softwood plywood is.
As such, it comes in a variety of sizes and shapes, both standard
and nonstandard. Common panel sizes are 48 inches wide in 84, 96,
and 120 inch lengths and 1/8 to 3/4 inch thicknesses. The most common
size encountered on the retail market is a 4 by 8 foot sheet in
3/8 inch thickness. Due to the speciality nature of hardwood plywood,
the specifications of a panel are determined more by the buyer than
the mill. The buyer can also specify the core material of the panel.
There are a number of options in core materials such as softwood
or hardwood veneer, softwood or hardwood lumber, particleboard,
hardboard, waferboard, and other specialty materials. It has been
estimated that about 38% of the production volume of cores is softwood
material (USDC 1987). Manufacturing tolerances for panels are listed
in Table 55.
Table 55. Hardwood plywood panel tolerances.
Length

± 1/32 inch

Width

± 1/32 inch

Thickness, unsanded

± 1/32 inch

Thickness, sanded

+ 0 3/64 inch for ≥
1/4 inch


+
0 1/32 inch for ≤ 1/4 inch

Source: USDC (1972); PS 5171.
Volume of Veneer or Panels. The
methods discussed above for softwoods apply. Hardwood veneer is
usually reported on a surface measure basis. To convert this to
cubic feet, use the thicknesses mentioned earlier, remembering
to convert them to feet. For 1/32 inch veneer use 0.0026 and for
1/16 inch use 0.0052 as the conversion factors from square foot
to cubic foot.
Hardwood plywood statistics are reported on either the
same SF_{3/8} basis as softwood plywood or on a surface measure
basis. The surface measure statistics often combine a number of
thicknesses, making conversion to cubic volume difficult.
Recovery
Efficiency
Material
Balance GreenEnd Recovery
The green end of a plant refers to all manufacturing activities
up to the point of drying veneer; the product of this portion of
the plant is clipped green veneer. Many facilities exist that produce
and market green veneer.
Figure
51. The percentage of block
volume recovered in various classes of green and dry
veneer. Source: Fahey (1987). 

From Mill Studies.
Figures 51 and 52 present a generalized material balance
for Douglasfir peeler blocks of different smallend diameters
(Fahey 1987). A block is the standard log segment mounted
in a lathe and is approximately 8.5 feet long. The figures
show the fraction of cubic volume that is converted into green
veneer, chips (roundup, spur trim, and reject veneer), and
the core (solid cylinder that remains after peeling). The
fraction of block cubic volume recovered as veneer is the
cubic recovery ratio (CRR).
As block diameter increases, the percentage of volume
recovered as green veneer increases, the percentage of core
decreases, and the percentage of chipped residuals is essentially
constant. The most rapid change occurs in smalldiameter blocks.
Dry veneer volume equals green veneer volume minus shrinkage
and panel trim. This loss is a constant percentage of green
veneer volume. Thus the dry veneer recovery is roughly 78%
of the green veneer recovery whatever the diameter (Fahey
1987). 
Figure 52 shows that percentage recovery
of veneer, chips, and core increases as block volume increases.
There are many factors that affect the volume recovered as
green veneer:
•The amount of defects present. Generally
blocks with large limbs, decay, sweep, and eccentric cross
section will yield less veneer. This can cause CRR to decrease
in larger block diameters, particularly from large younggrowth
blocks that may have very large limbs, leading to veneer
breakage, clipper loss, and belowgrade veneer.
•Coarseness
of growth.
Often fastgrown logs yield veneer with a rougher
surface or veneer that splits more easily during handling,
thus resulting in more clipper loss.
•Peeling
technology. Block centering equipment, optimizing
clipping equipment, and so forth, will increase recovery.
New lathe technology, such as the spindleless lathe, can
reduce core diameter and hence increase recovery.
•Veneer clipping policy. Particularly
important is the minimum size salvaged as random width strips
as well as salvage of fish tails.
•Market values and mill location. These
factors affect the marginal decision regarding what is converted
to veneer and what is chipped.
Material balances for various species can be obtained
from recovery studies conducted by the Timber Quality Research
Unit of the USDA Forest Service Pacific Northwest Research
Station. 

Figure
52. Volume of green or dry veneer
and of chips and core in relation to volume of the block.
Source: Fahey (1987). 

Theoretical Material Balance. Another
approach for predicting elements of the material balance is to
estimate them from simple mathematical relationships. See, for
example, the following elements (in cubic feet):
Block volume = 0.002727 _{* }(ds^{2 }+ dl^{2}) _{* }L (Smalian's cubic log volume)
Core volume = 0.005454 _{* }dc^{2 }_{* }L (cylinder)
Veneer volume = 0.005454 _{* }(ds^{2
} dc^{2}) _{* }L1 (difference
between two cylinders)
Residue = by subtraction
where
ds = small end diameter of block,
in inches
dl = large end diameter of block,
in inches
L = block length, in feet
dc = diameter of core, in inches
L1 = veneer length between spur
knives, in feet.
This approach gives theoretical yields that do not include
the effects of clipping, log abnormalities, and so forth. Thus the
veneer volume is overstated and residue volume is understated. The
technique is a useful way to study the effect of changes in log geometry
or core size on yield. The resulting cubic foot volume of veneer
can be easily expressed on a 3/8 inch basis or other thickness basis.
Material BalanceDryEnd Recovery
The material balance presented in Figures 51 and 52 also
shows recovery after "dryend" activities, including drying
veneer, reclipping, assembly into plywood, and panel trimming. Volume
change due to veneer shrinkage is 2 to 3%. Other losses, mainly panel
trim and sanding, are about 9 to 10%. Sometimes these dryend processes
are integrated with the greenend facilities in the same plant and
in other cases they are independent. Dryend recoveries can be expressed
either on an original block volume basis or in terms of green veneer
recovered, as illustrated in Table 56, which shows that 59.1% of
the original block volume (78.2% of the green veneer recovered) finds
its way into the finished panel.
Table 56. Veneer recovery of Douglasfir.
Use and loss

Percentage of
block volume

Percentage
of
green veneer volume



Block volume

100.0



Roundup, spur, clip

15.7



Peeler core

8.7



Green veneer

75.6

100.0


Shrinkage

8.3

11.0


Dry, untrimmed veneer

67.3

89.0


Trim, layup, other loss

8.2

10.8


Finished panel

59.1

78.2



Source: Fahey
(1987).
Recovery Efficiency Measures
Cubic Recovery Ratio (CRR). Cubic
recovery ratio is the cubic volume of recovered veneer divided by
the cubic volume of the veneer block or log, and can be calculated
for different stages of manufacture. Green cubic recovery ratio (CRR_{g})
is the actual volume of green clipped veneer divided by the block
volume, both in cubic feet. It is the measure in Figure 51. Dry cubic
recovery ratio (CRR_{d}) is the actual
volume of dry clipped veneer divided by block volume, both in cubic
feet. This includes shrinkage loss and additional dry clipping or
handling losses.Nominal green or dry cubic recovery ratio (CRR_{ng},
CRR_{nd}) can be based on the nominal sheet sizes rather than the
larger actual size needed to accommodate panel trim. With current
industry practice, the trim size effect is about 12% (Fahey 1987).
These measures reflect the net veneer that will be in finished plywood
panels rather than the total wood requirement. The USFS timber assessment
estimates a national average CRR_{nd} of 44.5% (Appendix 2). CRR_{nd}
is represented in Figures 51 and 52 by the "finished panel"
lines.
The above measures are typically based on the nominal panel
thickness (i.e., 1/8 inch, 1/10 inch, etc.) and can be amended by
using the actual thickness setting on the lathe. This is typically
larger than the nominal thickness to account for shrinkage, compression,
thickness variation, and so forth. Green target cubic recovery ratio
(CRR_{gt}) can be expressed for either the nominal
length and width of sheets or using the actual green sizes.
Veneer Recovery Factor (VRF). Veneer
recovery factor is the SF_{3/8}basis of recovered
veneer divided by the cubic feet of log volume. VRF can be calculated
as a counterpart to CRR for each of the degrees of manufacture discussed
in the previous section. The USFS timber assessment estimates a national
average of 14.1 square feet of 3/8 inch nominal veneer per cubic foot
of log used (Appendix 2).
Relationship Between CRR and VRF. Since
CRR = veneer, ft^{3} / log, ft^{3},
VRF = SF_{3/8}/ log, ft^{3},
and veneer, ft ^{3 }= SF_{3/8} / 32,
one can derive VRF_{3/8 }= 32 _{* }CRR.
See Example 3.
If a thickness basis (t) other than 3/8 inch is desired, remember
that SF_{3/8}= SM _{* }(t / 0.375),
hence
VRF_{t} = 12 _{*} CRR
/ t.
Since CRR and VRF can be measured for different states of
manufacture (i.e., green vs. dry veneer), it is important to maintain
consistency.
Veneer Recovery
and Board Foot Log Scale.
When board foot log scales are used, it is a common practice
of mills to relate veneer recovery to board foot volume of blocks.
This is also called a veneer recovery factor or veneer recovery
ratio (VRR), which is defined as the recovered veneer in SF_{3/8} basis divided by
BF log scale.
VRR historically has been between 2.5 and 3.0 SF_{3/8}per BF for various board foot log
scales. Recent improvements in technology, combined with smaller
logs that are underscaled in Scribner log scale, are pushing CRR
above 3.0. Because of the behavior of some BF log rules, the VRR
measure, like overrun for lumber, can be very sensitive to small
changes in block diameter and other factors unrelated to milling.
VRR does not behave in a consistent manner and thus is not a recommended
measure of mill efficiency.
This measure points out another inadequacy of board foot
log rules, which were originally designed to predict lumber outturn.
Here we see a strange hybrid where an estimate of lumber recovery
is used to predict veneer recovery.
Weight
of Veneer and Plywood
Shipping weights of veneer and lumber can usually be obtained
from appropriate trade associations and freight companies. In the
absence of this information, procedures outlined in Chapter 1 can
be used. See page 10 for examples for plywood and green veneer.
An 8 foot 6 inch long block is 16 inches in diameter at the small
end and 17 inches in diameter at the large end. It will be peeled
into 1/10 inch veneer with 100 inches (8.33 feet) between the spur
knives. The results presented are based on the nominal 1/10 inch
thickness. If the actual veneer thickness setting on the lathe is
0.108 inch, the quantities calculated can be adjusted accordingly.
Block volume (Smalian's formula)
12.6 ft^{3}
Recovery
1/10 inch veneer based on full dimension
of
recovered veneer
780 ft^{2}
Lineal footage of 1/10 inch veneer
=
780/8.33 93.6
ft
1/10 inch veneer based on nominal
dimension of sheets,
decrease by 12% 686 ft^{2}
3/8 inch basis:
Actual 208 ft^{2
}
Nominal 183 ft^{2}
Cubic feet: Actual
= 208/32 6.5 ft^{3}
Nominal = 183/32
5.7 ft^{3}
Cubic recovery ratio (CRRrg):
Actual
= 6.5/12.6 0.51 or 51%
Nominal
= 5.7/12.6 0.45 or 45%
Veneer recovery factor (VRFrg):
3/8
inch basis:
Actual
= 208/12.6 16.5 ft^{2}/ft^{3}
Nominal
= 183/12.6 14.5 ft^{2}/ft^{3}
Veneer recovery related to Scribner volume:
3/8
inch basis:
Scribner volume of a 16 inch
x 8 foot block = 80 BF
VRFScribner = 208/80
= 2.6 ft^{2}/BF
