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L-P-391D
November 19, 1975
SUPERSEDING
Fed. Spec. L-P-391C
May 28, 1971

FEDERAL SPECIFICATION

PLASTIC SHEETS, RODS AND TUBING, RIGID CAST,

METHACRYLATE (MULTIAPPLICATION)

This specification was approved by the Commissioner, Federal Supply Service,

General Services Administration, for the use of all Federal agencies.

1. SCOPE AND CLASSIFICATION

1.1 Scope. This specification covers methacrylate sheets, rods and tubes
produced by casting or machining cast blanks. This specification does not
apply to heat-formed and molded or extruded shapes, or shapes made by assem-
bling two or more pieces.

1.2 Classification (see 6.4)

1.2.1 Types and grades. The methacrylate sheets, rods, and tubes
conforming to this specification shall be of the following items, types, and
grades, as specified (see 6.2).

Item A - Plastic sheet.

Item B - Plastic rod.
Item C - Plastic tubing.
Item D - Plastic sheet having an abrasion resistant coating.

Type I - General purpose material having ultraviolet light

absorbing properties.
Type II - Special use material not having an ultraviolet
light absorber.
Type III - Type I sheet having an abrasion resistant coating on
one or both sides.
The following grades apply to both types I and II material. Grades B and C
sheet apply to type III sheet.

Grade AÀ1Ù - Special sheeting, thermally preshrunk sheet having

a smooth glossy surface.

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L-P-391D

Grade BÀ1Ù - Cell cast or continuous cast sheet, rods, and

tubes having a matte or patterned finish.

Grade CÀ1Ù - Cell cast or continuous cast sheet, rods, and

tubes having a smooth surface finish obtained
either by casting or highly polishing the
surface.

À1Ù All grades may be ordered trimmed to size or untrimmed.

2. APPLICABLE DOCUMENTS

2.1 The following documents, of the issues in effect on date of invitation

for bids or request for proposal, form a part of this specification to the
extent specified herein.

Federal Specifications:

PPP-B-585 - Boxes, Wood, Wirebound.

PPP-B-601 - Boxes, Wood, Cleated-Plywood.
PPP-B-621 - Boxes, Wood, Nailed and Lock-Corner.
PPP-B-636 - Box, Fiberboard.

Federal standards:

Fed. Std. No. 123 - Marking for Shipment (Civil Agencies).

Fed. Std. No. 00356 - Commercial Packaging of Supplies and Equipment.

(Activities outside the Federal Government may obtain copies of Federal

Specifications, Standards, and Handbooks as outlined under General
Information in the Index of Federal Specifications and Standards and at the
prices indicated in the Index. The Index, which includes cumulative monthly
supplements as issue, is for sale on a subscription basis by the
Superintendent of Documents, U. S. Government Printing Office, Washington,
D.C. 20402.

(Single copies of this specification and other Federal Specifications re-

quired by activities outside the Federal Government for bidding purposes are
available without charge from Business Service Centers at the General Service
Administration Regional Offices in Boston, New York, Washington, DC, Atlanta,
Chicago, Kansas City, MO, Fort Worth, Denver, San Francisco, Los Angeles, and
Seattle, WA.

(Federal Government activities may obtain copies of Federal Specifications,

Standards, and Handbooks and the Index of Federal Specifications and
Standards from established distribution points in their agencies.)

Military Specification:

MIL-P-116 - Preservation - Packaging, Methods of

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L-P-391D

Military Standards:

MIL-STD-105 - Sampling Procedures and Tables for Inspection by

Attributes.
MIL-STD-129 - Marking for Shipment and Storage.

(Copies of Military Specifications and Standards required by in connection

with specific procurement functions should be obtained from the procuring
activity or as directed by the contracting officer.)

2.2 Other publications. The following documents form a part of this

specification to the extent specified herein. Unless a specific Issue is
identified, the Issue in effect on date of invitation for bids or request for
proposal shall apply.

American Society for Testing and Materials (ASTM) Standards:

D 542 - Index of Refraction of Transparent Organic Plastics.

D 618 - Conditioning Plastics and Electrical Insulating Materials
for Testing.
D 637 - Surface irregularities of Flat Transparent Plastic Sheets.
D 638 - Tensile Properties of Plastics.
D 648 - Deflection Temperature of Plastics Under Flexural Load.
D 673 - Mar Resistance of Plastics.
D 756 - Resistance of Plastics to Accelerated Service Conditions.
D 792 - Specific Gravity and Density of Plastics by Displacement.
D 1003 - Haze and Luminous Transmittance of Transparent Plastics.
D 1044 - Resistance of Transparent Plastics to Surface Abrasion.
D 1308 - Effect of Household Chemicals on Clear and Pigmented Organic
Finishes.
D 1499 - Operating Light and Water Exposure Apparatus (Carbon-Arc Type)
for Exposure of Plastics.
D 1501 - Exposure of Plastics to Fluorescent Sunlamp.
D 3002 - Evaluation of Coatings for Plastics.

(Application for copies should be addressed to the American Society for

Testing and Materials, 1916 Race Street, Philadelphia, Pennsylvania 19103.)

National Motor Freight Traffic Association, Inc., Agent:

National Motor Freight Classification.

(Application for copies should be addressed to the American Trucking

Associations Inc., Tariff Order Section, 1616 P Street, N.W., Washington,
D.C. 20036.)

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L-P-391D

Uniform Classification Committee, Agent:

Uniform Freight Classification

(Application for copies should be addressed to the Uniform Classification

Committee, Room 1106, 222 South Riverside Plaza, Chicago, Illinois 60606.)

3. REQUIREMENTS

3.1 Material. The cast sheets, rods, and tubes shall be composed of
methacrylate plastics. Type III sheet shall consist of a cast methacrylate
substrate having an abrasion resistant coating an one or both sides.

3.2 Property values. The sheets shall conform to the property values
specified in table I and the rods and tubes shall conform to the property
values specified in table II, when tested as specified in the applicable
procedure of 4.3. For type III sheets, surface related tests shall be
performed on the coated side or sides.

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TABLE II. Property values for cast rods and tubes

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄ
Property ³ Type I ³ Type II
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄ
³ ³
Index of refraction, nÚD¿23 deg. C. min. ³ 1.48 ³ 1.40
max. ³ 1.50 ³ 1.50
³ ³
Specific gravityÀ1Ù, min. ³ 1.18 ³ 1.18
max. ³ 1.20 ³ 1.20
³ ³
Spectral transmittance at any wavelength,in the ³ ³
290 to 330 nm. band, 0.250 in. thickness max. ³ ³
percentÀ2Ù ³ 5 ³ NAÀ3Ù
³ ³
Deflection temperature under load at 264 p.s.i., ³ ³
min. deg. C. ³ ³
0.060 to 0.500 in. thick ³ 87 ³ 87
Above 0.500 to 1.000 ³ 90 ³ 90
Above 1.000 ³ 93 ³ 93
³ ³
Tensile strength, min., p.s.i. ³ 8000 ³ 8000
³ ³
Elongation at rupture, min., percent ³ 2 ³ 2
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄ
À1Ù For pigmented material, specific gravity shall be as specified by
the procuring agency.
À2Ù When testing other thicknesses, the value found shall be adjusted to
0.250 in. thickness. Thick rods, tubes, and shape* shall be machined
to 0.250 in. thickness and polished for testing.
À3Ù NA indicates not applicable.

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3.3 Thermal stability (applicable to grades A, D, and C sheet). Grades

A, B, and C sheet shall show no evidence of bubbling or blistering when
subjected to the thermal stability test.

3.4 Simulated weathering resistance.

3.4.1 Types I and II sheet. When specified by the procuring agency (see
6.2), types I and II sheet shall be subjected to simulated weathering (see
4.3.13.1) and shall show no evidence of cracking, crazing, surface
instability, discoloration, or other changes which prevent light
transmittance and haze properties from meeting the requirements specified in
table I.

3.4.2 Type III sheet. Type III sheet shall be subjected to simulated
weathering (see 4.3.13.2) and shall show no evidence of surface deterioration
which prevents abrasion and mar resistance, coating adhesion, and light
transmittance properties from meeting the applicable requirements specified
in table I.

3.5 Accelerated service conditions resistance (applicable only to type III

sheet). Type III sheet shall be subjected to accelerated service
conditioning (see 4.3.14) and shall show no evidence of change in abrasion
and mar resistance, and coating adhesion properties (see table I).

3.6 Color. Unless otherwise specified, sheets, rods, and tubes shall be
colorless. When color is specified, certain optical properties, including
refractive index, haze, and luminous transmittance, are not applicable. The
method of determination and the uniformity of the color shall be specified by
the procuring agency in consultation with the supplier (see 6.2).

3.6.1 End color of rods and tubes. When required, end color of rods and
tubes shall not exceed the limit defined by the color standard specified by
the procuring agency. The method of examination shall be as specified by the
procuring agency (see 6.2).

3.7 Dimensions and tolerances. All measurements shall be made either at

23 deg. +/- 2 deg. C (73.4 deg. +/- 3.6 deg. F), or corrected to 23 deg. C
(73.4 deg. F). When correction to 23 deg. C (73.4 deg. F is required,
pertinent information, including measurement temperature, shall be reported
to the procuring agency.

3.7.1 Sheets. The nominal length, width and thickness shall be as

specified by the procuring agency (see 6.2). For trimmed sheets, types I and
II, tolerance on length and width shall be +/- 0.125 inch. For untrimmed
sheets, types I and II, up to and including 1/2 inch thick, length and width
shall be not less than 2.5 percent larger than nominal. For untrimmed
sheets, types I and II, greater than 1/2 inch through 4 inches thick, length
and width shall be not less than 1 percent larger than nominal. Tolerances
for thickness of cell cast sheets shall be as specified in tables III and IV.

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Tolerances and thickness of continuous cast sheet shall be as specified in

table V. The standard widths for continuous cast sheet shall be 36 inches
through 96 inches and standard length shall be as specified in table V. Type
in sheet, cut to trimmed sizes, shall have the same tolerances as type I
sheet. Untrimmed type III sheet may have one or more edges trimmed, but the
dimensions. supplied shall be equal to or larger than nominal.

TABLE III. Nominal thickness and tolerances for

grade A (preshrunk) call cast sheets

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
Nominal thickness ³ Permissible thickness variation,
inch ³ inch
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
³ Size 1À1Ù ³ Size 2À2Ù ³ Size 3À3Ù
ÃÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
0.060 ³ +/-0.017 ³ +/-0.025 ³ NAÀ4Ù
0.080 ³ +/-0.017 ³ +/-0.025 ³ NA
0.100 ³ +/-0.017 ³ +/-0.025 ³ NA
0.125 ³ +/-0.020 ³ +/-0.025 ³ +/-0.035
0.187 ³ +/-0.025 ³ +/-0.030 ³ +/-0.035
0.250 ³ +/-0.030 ³ +/-0.035 ³ +/-0.040
0.312 ³ +/-0.035 ³ +/-0.040 ³ +/-0.045
0.375 ³ +/-0.040 ³ +/-0.045 ³ +/-0.050
0.500 ³ +/-0.045 ³ +/-10.05 ³ +/-0.050
0.625 ³ +/-0.055 ³ +/-0.055 ³ +/-0.055
0.750 ³ +/-0.055 ³ +/-0.055 ³ +/-0.060
0.875 ³ +/-0.055 ³ +/-0.055 ³ +/-0.070
1.000 ³ +/-0.055 ³ +/-0.055 ³ +/-0.075
1.250 ³ +/-0.070 ³ +/-0.070 ³ +/-0.100
1.500 ³ +/-0.080 ³ +/-0.080 ³ +/-0.120
1.750 ³ +/-0.095 ³ +/-0.095 ³ +/-0.140
1.875 ³ +/-0.105 ³ +/-0.105 ³ +/-0.155
2.000 ³ +/-0.105 ³ +/-0.105 ³ +/-0.155
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
À1Ù Size 1 - Nominal sheet sizes 36 by 60 inches and smaller, and 40 by 50
inches and smaller.
À2Ù Size 2 - Nominal sheet sizes larger than size 1 up to and including 46
by 84 inches, 53 by 80 inches, and 60 by 72 inches.
À3Ù Size 3 - Nominal sheet sizes larger than size 2 up to and including 67
by 102 inches, and 72 by 96 inches.
À4Ù NA indicates not applicable.

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TABLE IV. Nominal thickness and tolerance for

grades B and C cell cast sheets

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
Nominal thickness, ³ Permissible variation,
inchÀ1Ù ³ inch
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
³ Size 1À2Ù ³ Size 2À3Ù ³ Size 3À3Ù
ÃÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
³ ³ ³
0.030 ³ +0.007 ³ NA ³ NAÀ6Ù
³ -0.009 ³ ³
³ ³ ³
0.040 ³ +0.006 ³ NA ³ NA
³ -0.010 ³ ³
³ ³ ³
0.050 ³ +0.006À5Ù ³ NA ³ NA
³ -0.010 ³ ³
³ ³ ³
0.060 ³ +0.015 ³ +0.024 ³ NA
³ -0.019 ³ -0.027 ³
³ ³ ³
0.080 ³ +0.014 ³ +0.022 ³ NA
³ -0.020 ³ -0.028 ³
³ ³ ³
0.100 ³ +0.013 ³ +0.021 ³ NA
³ -0.021 ³ -0.029 ³
³ ³ ³
0.125 ³ +0.015 ³ +0.020 ³ +0.030
³ -0.025 ³ -0.030 ³ -0.040
³ ³ ³
0.150 ³ +0.016 ³ +0.022 ³ +0.029
³ -0.030 ³ -0.036 ³ -0.050
³ ³ ³
0.187 ³ +0.017 ³ +0.022 ³ +0.027
³ -0.033 ³ -0.038 ³ -0.043
³ ³ ³
0.220 ³ +0.020 ³ +0.025 ³ -0.029
³ -0.040 ³ -0.045 ³ -0.050
³ ³ ³
0.250 ³ +0.020 ³ +0.025 ³ +0.030
³ -0.040 ³ -0.045 ³ -0.050
³ ³ ³
0.312 ³ +0.022 ³ +0.027 ³ +0.032
³ -0.048 ³ -0.053 ³ -0.058
³ ³ ³
0.375 ³ +0.025 ³ +0.030 ³ +0.035
³ -0.055 ³ -0.060 ³ -0.065
³ ³ ³
0.500 ³ +0.025 ³ +0.030 ³ +0.035
³ -0.065 ³ -0.070 ³ -0.075
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ

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TABLE IV. Nominal thickness and tolerance for

grades B and C cell cast sheets (cont'd)

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
Nominal thickness, ³ Permissible variation,
inchÀ1Ù ³ inch
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
³ Size 1À2Ù ³ Size 2À3Ù ³ Size 3À3Ù
ÃÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
0.625 ³ +0.033 ³ +0.033 ³ +0.036
³ -0.077 ³ -0.077 ³ -0.082
³ ³ ³
0.750 ³ +0.030 ³ +0.030 ³ +0.040
³ -0.080 ³ -0.080 ³ -0.090
³ ³ ³
0.875 ³ +0.026 ³ +0.026 ³ +0.046
³ -0.084 ³ -0.084 ³ -0.104
³ ³ ³
1.000 ³ +0.023 ³ +0.023 ³ +0.048
³ -0.087 ³ -0.087 ³ -0.112
³ ³ ³
1.250 ³ +0.052 ³ +0.052 ³ +0.052
³ -0.094 ³ -0.094 ³ -0.094
³ ³ ³
1.500 ³ +0.039 ³ +0.039 ³ +0.077
³ -0.121 ³ -0.121 ³ -0.159
³ ³ ³
1.750 ³ +0.049 ³ +0.049 ³ +0.092
³ -0.137 ³ -0.137 ³ -0.180
³ ³ ³
2.000 ³ +0.058 ³ +0.058 ³ +0.108
³ -0.152 ³ -0.152 ³ -0.202
³ ³ ³
2.250 ³ +0.070 ³ +0.070 ³ NA
³ -0.166 ³ -0.166 ³
³ ³ ³
2.500 ³ +0.079 ³ +0.079 ³ NA
³ -0.181 ³ -0.181 ³
³ ³ ³
2.750 ³ +0.092 ³ +0.092 ³ NA
³ -0.194 ³ -0.194 ³
³ ³ ³
3.000 ³ +0.102 ³ +0.102 ³ NA
³ -0.208 ³ -0.208 ³
³ ³ ³
3,250 ³ +0.114 ³ +0.114 ³ NA
³ -0.222 ³ -0.222 ³
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ

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TABLE IV. Nominal thickness and tolerance for

grades B and C cell cast sheets (cont'd)

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
Nominal thickness, ³ Permissible variation,
inchÀ1Ù ³ inch
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
³ Size 1À2Ù ³ Size 2À3Ù ³ Size 3À3Ù
ÃÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
³ ³ ³
3.500 ³ +0.121 ³ +0.121 ³ NAÀ6Ù
³ -0.239 ³ -0.239 ³
³ ³ ³
3.750 ³ +0.134 ³ +0.134 ³ NA
³ -0.252 ³ -0.252 ³
³ ³ ³
4.000 ³ +0.142 ³ +0.142 ³ NA
³ -0.268 ³ -0.268 ³
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
À1Ù Thickness of unshrunk sheet will increase approximately 4 percent when
it is heated at thermoforming temperatures.
À2Ù Size 1 - Nominal sheet sizes 36 by 60 inches and smaller, 40 by 50
inches and smaller.
À3Ù Size 2 - Nominal sheet sizes larger than size 1 up to and including 48
by 84 inches, 53 by 80 inches, and 60 by 72 inches.
À4Ù Size 3 - Nominal sheet sizes larger than size 2 up to and including 67
by 102 inches, and 72 by 96 inches. Sheet sizes 48 by 120, and 84 by
132 inches are available in nominal thicknesses of 0.125, 0.187, and
0.250 inch, and in grade A only.
À5Ù For colorless sheet only, tolerances shall be +0.014, -0.009 for 0.030
inch thickness, +0.013, -0.017 for 0.040 inch thickness, and +0.013,
-0.017 for 0.050 inch thickness.
À6Ù NA indicates not applicable.

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TABLE V. Nominal thickness, length, and tolerances for

Grades B and C continuous cast sheetingÀ1Ù

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
³ Permissible variation ³ An supplied in reel form
³ in thickness, inch as ÃÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄ
³ supplied in reel ³ Standard nominal ³ Permissible
Nominal thickness, ³ form or flat sheet ³ length ³variation in
inch ³ ³ in feetÀ2Ù ³length, feet
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄ
³ ³ ³
0.080 ³ +/-0.010 ³ À2Ù ³ -0, +1
0.100 ³ +/-0.010 ³ À2Ù ³ -0, +1
0.110 ³ +/-0.011 ³ À2Ù ³ -0, +1
0.125 ³ +/-0.012 ³ À2Ù ³ -0, +1
0.135 ³ +/-0.013 ³ À2Ù ³ -0, +1
0.150 ³ +/-0.015 ³ À2Ù ³ -0, +1
0.170 ³ +/-0.017 ³ À2Ù ³ -0, +1
0.187 ³ +/-0.019 ³ À2Ù ³ -0, +1
0.220 ³ +/-0.022 ³ À2Ù ³ -0, +1
0.250 ³ +/-0.025 ³ À2Ù ³ -0, +1
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄ
À1Ù If defective portions are included in a continuous reel, they shall not
exceed 10% of the total length in feet supplied. The length of any
such defective portions are to be credited (deducted from the gross
footage supplied) at no cost to the purchaser.
À2Ù Nominal lengths of reels shall be as agreed upon between supplier and
procuring agency. Standard lengths vary from 250 to 750 feet as
thickness decreases. Nominal widths are 8 feet.

3.7.2 Rods. The nominal length and diameter shall be as specified by the
procuring agency (see 6.2). The tolerance on length shall be +/- 0.0625 inch
with Diameters no greater than 3.00 inches, and 0.125 inch for rods with dia-
meters above 3.00 inches. Tolerances for diameter shall be as specified in
table VI.

TABLE VI. Nominal diameter and tolerances of cast rods

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
Nominal diameter, inch ³ Diameter tolerances, inch
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
³
0.25 to 0.50 ³ +/-0.005
0.625 to 1.00 ³ +/-0.010
1.125 to 2.00 ³ +/-0.015
2.25 to 3.00 ³ +/-0.030
3.25 to 5.5 ³ +/-0.040
6.0 to 8.5 ³ +/-0.050
9 to 11 ³ +/-0.060
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
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3.7.3 Tubes. The nominal length, outside diameter, and wall thickness
shall be as specified by the procuring agency(see 6.2). The tolerance on
outside diameter and wall thickness shall be as specified in tables VII and
VIII. The tolerance for length shall be +/- 0.0625 inch.

TABLE VII. Nominal outside diameter and tolerance of cast tubes

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
³ Outside diameter tolerance, ³ Difference between maximum
³ inch ³ and minimum outside diameter
Nominal outside ÃÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ´ (one tube) not to exceed,
diameter, inch ³ Plus Minus ³ inch
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
1.500 to 3.000 ³ 0.010 0.020 ³ 0.025
3.125 to 3.875 ³ 0.015 0.030 ³ 0.040
4.000 to 6.094 ³ 0.015 0.045 ³ 0.060
7.000 to 12.000 ³ 0.015 0.065 ³ 0.080
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ

TABLE VIII. Nominal wall thickness and tolerances of cast tubes

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
³ Permissible wall thickness
Nominal wall thickness, inch ³ tolerance, inch
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
0.125 ³ +/-0.015
0.150 ³ +/-0.019
0.187 ³ +/-0.019
0.250 ³ +/-0.025
0.375 ³ +/-0.035
0.500 ³ +/-0.045
0.750 ³ +/-0.060
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ

3.8 Workmanship. The sheets, rods, and tubes shall be free from warpage,
cracks, scratches, blisters, voids, foreign matter and other defects that may
affect appearance or which may affect serviceability. Bubbles in rods and
tubes shall not exceed 0.156 inch in any dimension, and no more than three
such bubbles are acceptable in any standard length not less than 48 inches.
Bubbles are not permitted in rods and tubes less than 48 inches in length.

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3.8.1 Flatness of sheets (applicable only to cell cast sheets). Types I

and II sheet shall be free from edge kink warpage and from edge "S" warp.
Type III sheet less than or equal to 0.125 inch thick may have "S" warp with
a maximum deviation of 1.0 inch from a flat surface. Type III sheet greater
than 0.125 inch thick shall be free from edge kink warpage and from "S"
warp. Overall bow warp is permitted for all types of sheet if it can be
displaced by light finger pressure to conform to a flat surface.

3.8.2 Corner letgoes for sheets (applicable to either trimmed or untrimmed

sheets). Masked sheets in thicknesses equal to or less than 2.000 inches
shall be free of corner letgoes. Unmasked sheets in thicknesses no greater
than 0.250 inches may have letgoes within any or all of the corner areas
which are defined as isosceles triangles with 3-inch sides. Corner letgoes
in unmasked sheets that are thicker than 0.250 inches up to and including
2.000 inches are permitted within any or all of the corner areas which are
defined as isosceles triangles with 6-inch sides. For unmasked sheets
out-of-tolerance corner letgoes' within an isosceles triangle that has no
more than twice the allowable length for sides, shall be accepted if removed.
For masked and unmasked sheets in thicknesses greater than 2.000 inches,
letgoes may exist provided they do not extend more than 1/64 inch below the
surface. For continuous cast sheet only, edge letgoes less than 1/64 inch in
depth may exist within one inch of the sheet edges provided physical
integrity is not impaired.

3.8.3 Chips and dirt in sheets.

3.8.3.1 Chips for sheets in thickness equal to or less than 2.000 inches.
For type I and type II sheet, maximum permissible size shall be 0.125 inch.
For type III sheet, maximum permissible size shall be 0.187 inch. Chips that
are approximately the maximum permissible size for each type of sheets, shall
not have a frequency greater than one chip per 4 square feet of sheet area.
Chips less than the maximum permissible size for each type of sheet shall not
form a concentrated pattern that may affect serviceability. Chips
out-of-tolerance in size may be knifed off and considered acceptable if the
remaining blemish could be removed by polishing, except for type III sheets
which cannot be easily polished.

3.8.3.2 Chips for sheets in thicknesses greater than 2.000 inches.

Chips may exist providing they do not extend more than 1/64 inch above the
surface.

3.8.3.3 Dirt and contaminants. For type I and type II sheet, maximum
permissible dimension shall be 0.125 inch. For type III sheet, maximum
allowable dimension shall be 0.187 inch. Dirt and contaminants less than
1/32 inch shall be disregarded. The maximum permissible frequency for
dimensions ranging from 1/32 inch to the maximum permissible for each type of
sheet shall be one per 4 square feet of sheet area oar thickness up to and
including 0.500 inch, and 1 per square foot for thickness exceeding 0.125
inch.
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3.8.4 Other defects in sheets, rods, and tubes. Minor type defects such
as mold or handling scratches which can be removed by polishing shall be
permitted for type I and type II sheet provided these are not objectionable
individually or in grouped patterns. For type III sheet, maximum permissible
length for mold scratches shall be 1 inch; maximum permissible length for
medium or heavy handling scratches or abrasions shall be 2 inches; maximum
permissible length of light handling scratches or abrasions shall be 6
inches; scratches or abrasions lose than 0.250 inch and back-to-back mold
scratches shall be disregarded unless they form a concentrated pattern that
may affect serviceability. For type III sheet, the maximum permissible
frequency for allowable scratches and abrasions as defined above shall be one
per 4 square feet of sheet area. Excluding side letgoes for types I, II, and
III sheets in thicknesses greater than 2.000 inches and for unmasked sheets
that are thicker than 0.250 inches up to and including 2.000 inches, defects
within one inch of the untrimmed edge of the sheet, which do not
significantly reduce mechanical strength of the sheet, shall be permitted.
Side letgoes for sheets thicker than 2.000 inches may exist providing they do
not extend more than 1/64 inch below the surface. Side letgoes for unmasked
sheets thicker than 0.250 inches and up to and including 2.000 inches shall
be allowed within a 2 inch band from the untrimmed edge of the sheet. Rods
and tubes shall be free of striae and other blemishes that may affect
serviceability.

3.8.4.1 Optical clarity of rods (applicable to grade C only). Grade C

cast rods in 20 inch lengths, after polishing the ends, shall have optical
clarity that will enable clean print of the size 7 lines per column inch and
16 characters to the linear inch to be read when viewed through the length of
the rod under good illumination. The optical clarity of rods 3 inches and
less in diameter shall not be impaired by heating for the time period* and
temperatures specified in table IX, followed by cooling to 23 deg. +/- 2 deg.
C (73.4 deg. +/- 3.6 deg. F) before testing.

TABLE IX. Heating conditions for determining stability

of optical clarity of rodsÀ1Ù

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
Rod diameter, inches Temperature Time, minutes
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ

0.250 to 0.500 150 deg. C (302 deg. F) 30

0.625 to 1.5 145 deg. C (293 deg. F) 50
1.625 to 3.00 145 deg. C (293 deg. F) 75
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
À1Ù Rods larger than 3.0 inches in diameter and machined from large
castings, will not pass the optical clarity test after the heating
cycle.

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3.8.4.2 Turbidity of rods and tubes (applicable to grade C only). When

required, turbidity of grade C rods and tubes shall not exceed the limit
defined by a turbidity standard specified by the procuring agency. The
method of examination shall be as specified by the procuring agency (see
6.2).

4. QUALITY ASSURANCE PROVISIONS

4.1 Responsibility for inspection. Unless otherwise specified in the con-

tract or purchase order, the supplier is responsible for the performance of
all inspection requirements as specified herein. Except as otherwise speci-
fied, the supplier may utilize his own facilities or any commercial
laboratory acceptable to the Government. The Government reserves the right
to perform any of the inspections set forth in the specification where such
inspections are deemed necessary to assure that supplies and services conform
to prescribed requirements.

4.2 Sampling for inspection and acceptance. Sampling for inspection and
acceptance shall be performed in accordance with the provisions set forth in
MIL-STD-105, except where otherwise indicated. For purposes of sampling, an
inspection lot for examination and tests shall consist of all material of the
same type, grade, and nominal thickness submitted for delivery at one time.

4.2.1. Inspection of materials and components. In accordance with 4.1,

the supplier is responsible for insuring that materials and components used,
were manufactured, tested, and inspected in accordance with the requirements
of this specification, and to the extent specified. of all referenced
subsidiary specifications and standards. In the event of conflict, this
specification shall govern. A supplier's certificate of compliance with 3.1
shall be furnished.

4.2.2 Inspection of material.

4.2.2.1 Inspection of sheets, rods and tubes. Examination of sheets,

rods, and tubes shall be made in accordance with the classification of
defects, inspection levels and acceptable quality levels (AQLs) set forth
below. The lot size, for purpose of determining the ample size in accordance
with MIL-STD-105, shall be expressed in units of packages of plastic sheets,
rods, or tubes for examination in 4.2.2.1, and 4.2.2.2, and in units of
shipping containers for examination in 4.2.2.3.

4.2.2.1.1 Examination of sheets. rods, and tubes for defects in Appearance

and workmanship. The sample unit for the examination specified in table X
shall be one sheet, rod, or tube.

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TABLE X. Examination of sheets, rods, and tubes for defects

in appearance and workmanship

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
Examine Defects
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ

Sheets, rods and tubes Not free from warpage, cracks, scratches, blisters,
voids, and foreign matter (see 3.8).

Rods and tubes Bubbles not in accordance with 3.8.

Sheets Not free from edge kink warpage and edge "S" warp
(see 3.8.1). Not in accordance with 3.8.1 for type
III sheet equal to or less than 0.125 inch thick.

Sheets Letgoes exceeding dimensions specified (see 3.8.2).

Sheets Chips or dirt not in accordance with requirements

(see 3.8.3.1, 3.8.3.2, and 3.8.3.3).
Other defects not in accordance with requirements
(see 3.8.4).
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ

4.2.2.1.2 Examination of sheets, rods, and tubes for defects in

dimensions. The sample unit for the examination specified in table X shall
be one sheet, rod, or tube.

TABLE XI. Examination of sheets, rods, and tubes for dimensional defects

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
Examine Defects
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
Sheets Nominal length, width, or thickness not as
specified.
Length or width tolerance not an specified in
3.7.1.
Thickness tolerance not as specified in tables III,
IV, and V.

Rods Nominal length and diameter not as specified.

Tolerance for length not as specified in 3.7.2.
Tolerances for diameter not as specified in
table VI.

Tubes Nominal length, outside diameter, and wall

thickness not as specified.
Tolerance for outside diameter not as specified
in table VII.
Tolerance for wall thickness not as specified
in table VIII.
Tolerance for length not as specified in 3.7.3.
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ

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4.2.2.1.3 Examination of preparation for delivery. An examination in

accordance with table XII, shall be made to determine that packaging,
packing, and marking comply with specified contract requirements. The sample
unit for this examination shall be one shipping container fully packed,
selected just prior to the closing operation. Shipping containers fully
prepared for delivery shall be examined for closure defects.

TABLE XII. Examination for defects in preparation for delivery

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
Examine Defect
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ

Packaging Not level specified.

Not individually packaged, multiple packaged, or
intermediate packaged, as specified.
Packaging material not as specified: closure not
accomplished by specified or required methods or
materials; component missing.
Weight of intermediate package exceeds specified
requirements.

Packing Not level specified.

Containers not as specified, closures not
accomplished by specified or required method of
materials.
Any nonconforming component, component missing,
damaged or otherwise defective, affecting
serviceability.

Count Less than specified or indicated quantity.

Weight Gross weight exceeds specified requirements.

Markings Interior or exterior markings, as applicable,

omitted, illegible, incorrect, incomplete, of
improper size, location, sequence or method of
application, or not in accordance with contract
requirements.
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ

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4.2.2.1.4 Inspection levels and AQLs for examinations. The inspection

levels for determining the sample size and the AQL, expressed an defects per
100 units shall be as follows:

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
Examination Inspection
paragraph level AQL
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ

4.2.2.1.1 I 2.5
4.2.2.1.2 S-2 4.0
4.2.2.1.3 S-2 2.5
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ

4.2.3 Testings. The sheets shall be tested for the applicable characteris-
tics listed in table I, and the rods and tubes for the applicable character-
istics listed in table II, in accordance with the test method specified
herein f or each lot submitted for inspection. The lot size, for the purpose
of determining sample size for testing shall be expressed in units of
packages of sheets, rods, or tubes, as applicable. The sample unit shall
consist approximately of only sufficient material to prepare all required
specimens. The inspection level shall be S-1 with an acceptance number of 0.
When the test method requires testing more than one specimen, the results for
each test shall be the averaged results of the specimens.

4.2.3.1 Classification of tests. All tests shall be classified as

follows:

a. Lot acceptance tests (see 4.2.3.2).

b. Periodic lot check tests (see 4.2.3.3).

4.2.3.2 Lot acceptance tests. Lot acceptance tests shall be made on each
lot of sheets, rods, or tubes, as applicable, and, in conjunction with the
above examination, shall be the basis for acceptance or rejection of the lot,
except when periodic lot check tests are required. For type I and II sheet,
lot acceptance tests shall consist of tests for specific gravity, spectral
transmittance (for type I only), shrinkage, and deflection temperature under
load (see table I). For type III sheet lot acceptance tests shall consist of
tests for specific gravity, spectral transmittance, deflection temperature
under load, abrasion resistance, mar resistance and coating adhesion (see
table I). For rods and tubes, lot acceptance tests shall consist of tests
for specific gravity, spectral transmittance (for type I only), and
deflection temperature under load (see table II).

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4.2.3.3 Periodic lot check tests. Periodic lot check tests shall be
made on the first lot of material furnished under this specification, and
on any subsequent lot specified by the procuring agency (see 6-2). For
grades B and C sheet, periodic lot check tests shall consist of all tests
specified in table I and the thermal stability test (see 3.3). For grade A
sheet, periodic lot check tests shall consist of all tests specified in table
I. For type III sheet, periodic lot check tests shall consist of all tests
specified for grade C and the simulated weathering and accelerated service
conditions tests (see 4.3.13.2 and 4.3.14). For rods and tubes, periodic lot
check tests shall consist of all tests specified in table II. When periodic
lot check tests are made, they shall be included in the basis for acceptance
or rejection of the lot.

4.3 Test methods.

4.3.1 Test specimen preparation. Unless otherwise specified, the dimen-

sions of specimens shall conform to that specified in the applicable test
procedure.

4.3.1.1 Sheets. Test specimens shall be cut from sheet. When 0.250 inch
thick sheet is not available for spectral transmittance determination, lower
thicknesses may be used with adjustment of the values to that for 0.250 inch
thick specimens. The method of adjustment shall be as specified by the pro-
curing agency (see 6.2). Sheets with thickness greater than 0.250 inch shall
be machined to 0.250 inch thickness and polished before measuring spectral
transmittance.

4.3.1.2 Rods and tubes. Test specimens shall be cut from the rods or
tubes, as applicable, if test specimens cannot be cut from rods or tubes,
specimens shall be prepared from the same material under conditions specified
by the manufacturer.

4.3.2 Test specimen conditioning. Unless otherwise specified, test speci-

mens shall be conditioned in accordance with procedure A of ASTM D 618 and
tested at 23 deg. 2 deg. C (73.4 deg. +/- 3.6 deg. F) and 50 +/- 5 percent
relative humidity.

4.3.3 Index of refraction. One specimen shall be tested in accordance

with ASTM D 542.

4.3.4 Specific gravity. One specimen shall be tested in accordance with

method A of ASTM D 792.

4.3.5 Haze (applicable only to grade C sheet). One specimen shall be

tested in accordance with ASTM D 1003, except that test specimens shall not
exceed 0.500 inches in thickness.

4.3.6 Light transmittance (applicable only to grade C sheet). One speci-

men shall be tested in accordance with ASTM D 1003, at the same time it is
tested in accordance with 4.3.5.

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4.3.7 Spectral transmittance in the ultraviolet region (applicable only to

type I and type III grade C sheet, and type I rods and tubes). One specimen
shall be tested for spectral transmittance in 290 to 330 nonometers (nm.)
wavelength band. The spectral transmittance shall be determined by means of
a monochromator having a band width of 10 on. or less and a photometer having
a reproducibility of +/- 1 percent of full scale.

4.3.8 Displacement factor (applicable only to grade C sheet). One test

specimen 18.0 +/- 0.1 by 18.0 +/- 0.1 inch shall be tested in accordance with
ASTM D 637.

4.3.9 Shrinkage (applicable to sheet only). Two specimens, each 12.0 ñ

0.1 by 12.0 +/- 0.1 inch, shall be tested. On each specimen, two fine lines
shall be marked at right angles to each other entirely across the specimen
from the midpoints of opposite sides. Fine gage marks shall be placed across
each of these lines and 2.0 +/- 0.1 inches from the edge of the specimen.
The distance between each pair of gage marks shall be measured to the nearest
0.01 inch. Each specimen shall be suspended from one end in a circulating
air oven at 180 deg. +/- 10 deg. C (320 deg. +/- 18 deg. F), for the length
of time specified in table XIII. After removal from the oven, the specimens
shall be allowed to cool to 23 deg. +/- 1 deg. C (73.4 deg. +/- 1.8 deg. F),
while in the suspended position. The distance between each pair of gage
marks shall be remeasured and the shrinkage calculated as the percentage
change in distance between gage marks based on the original distance.

TABLE XIII. Heating time for shrinkage test

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
Nominal sheet thickness,À1Ù Minimum heating time,
inches minutes
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ

0.250 and less 16

0.375 25
0.500 33
0.750 55
1.000 79
1.500 136
2.000 203
2.250 and above 240
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ

À1Ù For thickness falling between that specified, use the heating time for
the next higher thickness.

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4.3.10 Deflection temperature under load. Three specimens shall be tested

in accordance with ASTM D 648. Any square, rectangular, or cylindrical test
specimen may be used, but the test load must be calculated on the basis of a
center-loaded beam in which the outer fiber stress produced is 264 p.s.i.
Pieces of thin sheet shall be staked and bound together to 0.500 t 0.050 inch
in width to form a specimen 0.500 +/- 0.050 by 0.500 +/- 0.050 inch.
Specimens shall be loaded parallel to the faces containing the original
surfaces of material. Specimens 0.500 +/- 0.050 by 0.500 +/- 0.050 inch,
machined from face of thick material, shall be loaded parallel to the face
containing the original surface.

4.3.11 Tensile strength and elongation. Three specimens shall be tested

in accordance with ASTM D 638, using testing speed B. Dimensions of each
specimen shall conform to type I of figure 1 of ASTM D 638 and shall be of
the thickness an received, except when thickness exceeds 1.00 inch. When
thickness exceeds 1.00 inch, the specimen shall be machined down to a
convenient thickness not exceeding 1.00 inch.

4.3.12 Thermal stability. Two sheets, each 12 by 12 inches, shall be

tested. Each sheet shall be hung in a circulating air oven at 180 deg. +/- 5
deg. C (356 +/- 9 deg. F). Time of heating shall be 1/2 hour for 3/8 inch
thickness and under, 1 hour for above 3/8 inch to 1 inch inclusive, and 2
hours for over 1 inch thickness. After removal from the oven, the sheeting
shall be permitted to cool to 23 deg. +/- 2 deg. C (73.4 deg. +/- 3.6 deg. F)
while hanging vertically. The sheeting shall be examined visually for the
presence of bubbles and blisters.

4.3.13 Simulated weathering resistance.

4.3.13.1 Types I and II sheet (required only when specified by the

procuring agency (see 3.4 and 6.2). Two specimens shall be tested in
accordance with procedure C of ASTM D 1501. Specimens shall be of convenient
dimensions and not exceed 0.236 inches in thickness.

4.3.13.2 Type III sheet. Two specimens shall be tested in accordance with
ASTM D 1499 for 1000 +/- 10 hours. Specimens shall be of convenient
dimensions, but not smaller than 2.75 by 4.0 inches, and shall be subjected
to the water spray cycle. For one side coated sheet, the coated side shall
be exposed.

4.3.14 Accelerated service conditions resistance (applicable only to SW

III sheet). Six specimens shall be tested in accordance with procedure A of
ASTM D 756. Tests 4.3.15, 4.3.16, and 4.3.17 shall be run after 8.4 and
8.10 of procedure A of ASTM D 756.

4.3.15 Abrasion resistance (Applicable to type III sheet only). One

specimen shall be tested in accordance with ASTM D 1044, using a 500 gram
load on each wheel for 100 cycles.

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4.3.16 Mar resistance (applicable to type III sheet only). One specimen
shall be tested in accordance with ASTM D 673 using 1000 grams of No. 80
silicon carbide (carborundum or equivalent) as the abrasive.

4.3.17 Coating adhesion (applicable to type III sheet only). One specimen
shall be tested in accordance with section 8.1 of ASTM D 3002, except as
follows: The surface shall be cleaned using isopropyl alcohol with a soft
cloth and then air dried. Four parallel cuts shall be made 1/8 inch apart
and a similar set of cuts 90 degrees to the first. The debris shall be re-
moved with light hand rubbing using 0000 grade steel wool being careful not
to contaminate the test area with grease or fingerprints. A strip of 1.0
inch wide cellulose tape (3M Company #600 or equivalent) shall be applied
pressing the tape down firmly without wrinkles or bubbles. The tape shall be
removed immediately by quickly pulling it at a 90 degree angle. The tape
pull shall be repeated two times in the same grid area being careful not to
contaminate the grid by touching it. The area from which the coating has
been removed shall be estimated, expressing it as a percentage of the total
area within the grid.

4.3.18 Chemical resistance (applicable to type III sheet only). One

specimen shall be tested in accordance with section 5.2 of ASTM D 1308 except
that a 1/2 by 1/2 inch square of filter paper shall be saturated on the
surface to be tested with 1 ml of reagent and covered with a watch glass.
After one hour, the glass and filter paper shall be removed and the surface
flushed with methanol to remove the reagent. The area shall be wiped dry and
examined for effects listed in section 1 of ASTM D 1308. Test reagents shall
be:

3% trisodium phosphate
40% sulfuric acid
toluene

5. PREPARATION FOR DELIVERY

5.1 Preservation and packaging shall be level A or C, as specified (see

6.2).

5.1.1 Level A. maximum Military protection. Unless otherwise specified

in the contract or order (see 6.2), sheet, rods, and tubes shall be packaged
in quantities specified by the procuring agency in accordance with method III
of MIL-P-116. Shapes of only one set of nominal dimensions shall be placed
in one package. Individual sheets shall be masked or unmasked at the option
of the procuring agency.

5.1.2 Commercial. Sheets, rods, and tubes shall be packaged to provide a

sufficient level of protection to prevent deterioration during shipment and
to ensure safe delivery at destination.

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L-P-391D

5.1.3 Disposability (see 6.5).

5.2 Packing. Packing shall be level A, B, or C, as specified (see 6.2)

5.2.1 Level A. maximum Military protection. Sheet, rods and tubes pack-
aged as specified in 5.1.1 shall be separated by form, diameter and wall
thickness, and shall be packed in containers conforming to any of the
following specifications, at the option of the supplier:

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
Specification Type or class
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
PPP-B-585 Class 3
PPP-B-601 Overseas type
PPP-B-621 Class 2
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ

Boxes shall be closed, strapped, or banded in accordance with the applicable

box specification or appendix. The gross weight of the shipping container
shall be as specified in the applicable container specification.

5.2.2 Level B. minimum Military protection. Packages of sheet, rods, or

tubes shall be packed in domestic class or type shipping containers conform-
ing to PPP-B-585, PPP-B-601, PPP-B-621, or PPP-B-636. All containers be
closed in accordance with the applicable container specification or appendix.
The gross weight of the shipping container shall be as specified in the
applicable specification.

5.2.3 Commercial. The sheet, including rolls of sheeting, rod or tubes,,

packaged as specified in 5.1, shall be packed in a manner to erasure carrier
acceptance and safe delivery at destination at the lowest transportation rate
for such supplies. Containers shall be in accordance with Uniform Freight
Classification Rules or National Motor Freight Classification Rules, as
applicable.

5.2.4 Disposability (see 6.5).

5.3 Marking.

5.3.1 Civil agencies. Unit packages and shipping containers shall be

marked in accordance with Fed. Std. No. 123.

5.3.2 Military agencies. In addition to any special marking required by

the contract or purchase order, unit packages and shipping containers shall
be marked in accordance with MIL-STD-129. When individual sheets are masked,
the applicable FSN of the sheet shall be marked on the masking material in at
least one place on each sheet.

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L-P-391D

5.3.3 Commercial. Unit packages and shipping containers shall be marked

in accordance with Fed. Std. No. 00356.

6. NOTES

6.1 Intended use. The sheet, rods and tubes covered by this specification
are intended for use in applications where transparency, color range, weather
resistance and other characteristics of cast acrylic shapes are required.
Type I material is intended for use where the ultraviolet light absorbing
properties specified in tables I or II, as applicable, are required. Type II
material is intended for use where the ultraviolet light absorbing
properties, specified for type I material, are not required. Type I and II
sheet are not intended for use in aircraft glazing or other applications
requiring consistently high optical quality. Type III sheet is intended for
use in applications requiring good optical quality, cleanability or
serviceability under adverse environmental conditions. Applications include
diffusing lighting shields, window glazing, card holders, chart covers, edge
lighted signs, surgical instrument handles and parts, safety shielding and
transparent models. Type III sheet is not readily cemented using
conventional cements for acrylic resins. The coating can be removed by
sanding or buffing the areas to be cemented. Continuous cast sheet have
better thermoformability than cell cast sheet, and the continuous cast
process is less expensive.. However, It should be cautioned that, if the
continuous cast sheet are to be used in forming applications, frequent
adjusting (temperature, pressure, time of forming cycle, etc.) of the forming
machinery may be required and this could offset any savings. Due to the
continuous mixing, the uniformity of blend for the continuous cast sheet may
be less consistent than that of the cell cast sheet which is cast from a
premixed batch. Also due to the ripple effects (waves) the continuous cast
sheet may be marginal in use for applications such as optical windows.

6.2 Ordering data. Purchasers should select the preferred options

permitted herein and include the following information in procurement
documents:

(a) Title, number, and date of this specification.

(b) Type and grade of cast methacrylate sheets, rods, or tubes, as
applicable. Type III sheet shall be coated both sides unless
otherwise stated.
(c) Use of cell cast or continuous casting process, if required.
(d) Color and method of determination, including uniformity if
required (see 3.6). Also, end color standard for rods and
tubes, when required (see 3.6.1), including method of
determination.
(e) Simulated weathering resistance if required (see 3.4).
(f) Specific gravity, if pigmented material is required (see
tables I and II).
(g) Deflection temperature, if thickness is less than 0.060
(see table I).

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L-P-391D

(h) Length, width and nominal thickness of sheets (see 3.7.1).

Length and nominal diameter of rods (see 3.7.2)
(i) Length, nominal outside diameter, and nominal wall thickness
of tubes (see 3.7.3).
(j) Turbidity standard for rods and tubes, when required (see
3.8.4.2). Also, method for determination.
(k) Periodic lot check tests, when required (see 4.2.3.3).
(l) Adjustment of spectral transmittance value for sheet, if
required (see 4.3.1.1).
(m) Selection of the applicable levels of packaging and packing
required (see 5.1 and 5.2).
(n) Quantities of rods and tubes required in the unit packages

6.3 Terminology. As used in this specification tubes and tubing are

identical.

6.4 Cross index. Table XIV shows the classification of material covered
by this specification and the corresponding classification of material.

TABLE XIV. Classification in this document and corresponding

classification in L-P-391C

ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
L-P-391D Classification in L-P-391C
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ

Type I Type I
Type II Type II
Type III None
Grade A sheet Grade A
Grade B sheet Grade D
Grade C sheet Grade C
None Grade B sheet
Grade A rods and tubes Grade A
Grade B rods and tubes Grade A
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ

6.5 Disposability of packaging and packing materials. Environmental

pollution preventive measures are contained in the packaging and packing
material specifications indicated in section 2. Refer to these
specifications for recommended disposability methods.

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L-P-391D

MILITARY CUSTODIANS: Preparing activity:

Army - MR Army - MR
Navy - SH
Air Force - 11
Civil Agency Coordinating Activities:

Review activities: GSA-FSS

Army - EL, MI, ME

Navy - AS, SH
DSA - GS

User activities:

Army - GL, PA
Navy - OS, YD

Orders for this publication are to be placed with General Services

Administration, acting as an agent for the Superintendent of Documents. See
section 2 of this specification to obtain extra copies and other documents
referenced herein. Price 65 cents each.

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INCH-POUND

L-P-391D
AMENDMENT 1
6 June 1990

FEDERAL SPECIFICATION
PLASTIC SHEETS, RODS AND TUBING, RIGID CAST,
METHACRYLATE (MULTIAPPLICATION)

This amendment forms a part of Federal Specification L-P-391D dated 19

November 1975 and is approved for use by the Department of the Army and is
available for use by all Departments and Agencies of the Department of
Defense.

PAGE B-2

3.8.2 Delete the first sentence and substitute the following:

"Masked sheets of thickness equal to or less than 2.000 inches shall be
free of let-goes within their specified minimum nominal length and width.

NOTE: A let-go is commonly defined as an area of laminated glass where the

initial adhesion between glass and interlayer is debonded.

Custodians: Preparing activity:

Army - MR Army - MR
Navy - SH
Air Force - 11 Civil Agency Coordinating Activities:

Review activities: GSA - FSS (7EXEG)

Army - CR, MI, ME ERDA
Navy - AS NASA MSF
DLA - GS
Project 9330-1149
User activities:
Army - GL, PA
Navy - OS, YD

AMSC N/A 1 of 1 FSC 9330

DISTRIBUTION STATEMENT A Approved for public release: distribution

unlimited.
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ÚÄÄÄÄÄÄÄÄÄÄÄÄ¿
³ NOTICE OF ³ L-P-391D
³ VALIDATION ³ NOTICE 1
ÀÄÄÄÄÄÄÄÄÄÄÄÄÙ 10 February 1987

TITLE: Plastic Sheets, Rods and Tubing, Rigid Cast, Methacrylate

(Multiapplication)

L-P-391D, dated 19 Nov 75, has been reviewed and determined to be valid
for use in acquisition.

Custodians: Military Coordinating Activity:

Army - MR Army -MR
Navy - SH
Air Force - 11

AMSC N/A FSC 9330

DISTRIBUTION STATEMENT A Approved for public release; distribution

unlimited.