ASTM_C_59_-_C_59M_-_00_2015.pdf

Designation:C59/C59M00(Reapproved 2015)Standard Specification forGypsum Casting Plaster and Gypsum Molding Plaster1This standard is issued under the fixed designation C59/C59M;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript 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.Scope1.1 This specification covers gypsum casting plaster andgypsum molding plaster materials consisting essentially ofcalcined gypsum.1.2 The values stated in either inch-pound or SI(metric)units are to be regarded as standard.Within the text,the SIunits are shown in brackets.The values stated in each systemshall be used independently of the other.Values from the twosystems shall not be combined.1.3 The text of this standard references notes and footnotesthat provide explanatory material.These notes and footnotesshall not be considered as requirements of the standard.2.Referenced Documents2.1 ASTM Standards:2C11 Terminology Relating to Gypsum and Related BuildingMaterials and SystemsC471M Test Methods for ChemicalAnalysis of Gypsum andGypsum Products(Metric)C472 Test Methods for Physical Testing of Gypsum,Gyp-sum Plasters and Gypsum ConcreteE11 Specification for Woven Wire Test Sieve Cloth and TestSieves3.Terminology3.1 Definitions of terms shall be in accordance with Termi-nology C11.3.2 Definitions of Terms Specific to This Standard:3.2.1 gypsum casting plaster,na calcined gypsum plasterused primarily to form objects,such as lamp bases,art ware,and novelties,etc.3.2.2 gypsum molding plaster,na calcined gypsum plasterused primarily for plaster casts or molds,sometimes used as agauging plaster.4.Chemical Composition4.1 Gypsum casting plaster and gypsum molding plastershall have a purity of not less than 85%CaSO42H2O whentested in accordance with Test Methods C471M.5.Physical Properties5.1 Specimens shall be tested in accordance with TestMethods C472.5.1.1 Setting TimeGypsum casting plaster and gypsummolding plaster shall set in not less than 10 nor more than 50min using the procedure for gypsum concrete and all gypsumplasters,except gypsum neat plaster.5.1.2 Compressive StrengthGypsum casting plaster andgypsum molding plaster shall have a compressive strength ofnot less than 1800 psi 12.4 MPa.5.1.3 FinenessGypsum casting plaster and gypsum mold-ing plaster shall all pass a No.30 600-m sieve and not lessthan 90%shall pass a No.100 150-m sieve.36.Sampling6.1 Randomly select not less than 1%of the packages,butnot less than 5 packages.Take samples of approximately equalamounts both from the outer portion and the center of eachpackage.Mix the samples so obtained to provide a compositesample of not less than 7 lb 3 kg.Immediately place thecomposite sample in a clean,dry,airtight container for deliveryto the laboratory.7.Inspection7.1 Inspection of the gypsum casting and molding plastershall be agreed upon by the purchaser and the supplier as partof the purchase agreement.8.Rejection8.1 Rejection of gypsum casting plaster and gypsum mold-ing plaster that fails to conform to the requirements of this1This specification is under the jurisdiction of ASTM Committee C11 onGypsum and Related Building Materials and Systems and is the direct responsibilityof Subcommittee C11.01 on Specifications and Test Methods for Gypsum Products.Current edition approved Oct.1,2015.Published October 2015.Originallyapproved in 1926.Last previous edition approved in 2011 as C59/C59M 00(2011).DOI:10.1520/C0059_C0059M-00R15.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Detailed requirements for these sieves are given in ASTM Specification E11.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 specification shall be reported to the producer or supplierpromptly and in writing.The notice of rejection shall contain astatement documenting how the gypsum casting and moldingplaster have failed to conform to the requirements of thisspecification.9.Certification9.1 When specified in the purchase agreement,a producersor suppliers report shall be furnished at the time of shipmentcertifying that the product is in compliance with this specifi-cation.10.Packaging and Package Marking10.1 Gypsum casting plaster and gypsum molding plastersshall be dry and free of lumps and shall be shipped in packages.10.2 When shipped,the following information shall belegibly marked on each package or on a tag of suitable sizeattached thereto:10.2.1 Name of manufacturer or seller,10.2.2 Brand,10.2.3 Description,and10.2.4