ASTM C59/C59M-00(2020)
(Specification)Standard Specification for Gypsum Casting Plaster and Gypsum Molding Plaster
Standard Specification for Gypsum Casting Plaster and Gypsum Molding Plaster
ABSTRACT
This specification covers casting and molding plaster materials consisting essentially of calcined gypsum. The chemical composition of each plaster material should meet the required purity value. For samples, equal amounts of material should be taken from the outer and center of each package. Specimens shall also be tested for setting time, compressive strength and fineness.
SCOPE
1.1 This specification covers gypsum casting plaster and gypsum molding plaster materials consisting essentially of calcined gypsum.
1.2 The values stated in either inch-pound or SI units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.
1.3 The text of this standard references notes and footnotes that provide explanatory material. These notes and footnotes shall not be considered as requirements of the standard.
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
General Information
Relations
Standards Content (Sample)
This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: C59/C59M −00 (Reapproved 2020)
Standard Specification for
Gypsum Casting Plaster and Gypsum Molding Plaster
This standard is issued under the fixed designation C59/C59M; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope 3.1.1 Fordefinitionsoftermsusedinthisspecification,refer
to Terminology C11.
1.1 This specification covers gypsum casting plaster and
3.2 Definitions of Terms Specific to This Standard:
gypsum molding plaster materials consisting essentially of
3.2.1 gypsum casting plaster, n—a calcined gypsum plaster
calcined gypsum.
used primarily to form objects, such as lamp bases, art ware,
1.2 The values stated in either inch-pound or SI units are to
and novelties, etc.
be regarded separately as standard. The values stated in each
system are not necessarily exact equivalents; therefore, to
3.2.2 gypsum molding plaster, n—a calcined gypsum plaster
ensure conformance with the standard, each system shall be
used primarily for plaster casts or molds, sometimes used as a
used independently of the other, and values from the two
gauging plaster.
systems shall not be combined.
4. Chemical Composition
1.3 The text of this standard references notes and footnotes
that provide explanatory material. These notes and footnotes
4.1 Gypsum casting plaster and gypsum molding plaster
shall not be considered as requirements of the standard.
shall have a purity of not less than 85 % CaSO ·2H O when
4 2
1.4 This international standard was developed in accor-
tested in accordance with Test Methods C471M.
dance with internationally recognized principles on standard-
ization established in the Decision on Principles for the
5. Physical Properties
Development of International Standards, Guides and Recom-
5.1 Specimens shall be tested in accordance with Test
mendations issued by the World Trade Organization Technical
Methods C472.
Barriers to Trade (TBT) Committee.
5.1.1 Setting Time—Gypsum casting plaster and gypsum
2. Referenced Documents
molding plaster shall set in not less than 10 nor more than
2.1 ASTM Standards:
50 min using the procedure for gypsum concrete and all
C11 Terminology Relating to Gypsum and Related Building
gypsum plasters, except gypsum neat plaster.
Materials and Systems
5.1.2 Compressive Strength—Gypsum casting plaster and
C471M Test Methods for ChemicalAnalysis of Gypsum and
gypsum molding plaster shall have a compressive strength of
Gypsum Products (Metric)
not less than 1800 psi [12.4 MPa].
C472 Test Methods for Physical Testing of Gypsum, Gyp-
5.1.3 Fineness—Gypsum casting plaster and gypsum mold-
sum Plasters, and Gypsum Concrete
ing plaster shall all pass a No. 30 [600 µm] sieve and not less
E11 Specification for Woven Wire Test Sieve Cloth and Test
than 90 % shall pass a No. 100 [150 µm] sieve (Note 1).
Sieves
NOTE 1—Detailed requirements for these sieves are given in Specifi-
3. Terminology
cation E11.
3.1 Definitions:
6. Sampling
This specification is under the jurisdiction of ASTM Committee C11 on
Gypsum and Related Building Materials and Systems and is the direct responsibility
6.1 Randomly select not less than 1 % of the packages, but
of Subcommittee C11.01 on Specificat
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.