ASTM_D_6737_-_12_2017.pdf

Designation:D673712(Reapproved 2017)Standard Test Method forBulk Density of Tapered Paintbrush Filaments1This standard is issued under the fixed designation D6737;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.1.Scope1.1 This test method covers a procedure for measuring theweight of filaments per unit volume.1.2 This method is applicable only to monofilament withtapered longitudinal profiles.1.3 The values given in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.4 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.1.5 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Summary of Test Method2.1 The weight,length and diameter of a bundle of taperedfilaments are measured,and the bundle density is calculated.3.Significance and Use3.1 Filaments are available in a variety of cross-sections andmaterials.Ameasure of bulk density permits the brushmaker toestimate the weight of filament required to prepare a givennumber of brushes.4.Apparatus4.1 The apparatus requires some machining,and is as-sembled as shown in Fig.1 from the following equipment:4.1.1 Air Valve.24.1.2 Miniature Air Cylinder,dual acting,heavy duty.34.1.3 Assorted parts shown in Fig.1 are machined from 304stainless steel and assembled as shown along with the air valveand cylinder just described.The Pi tape4must be fixed in placeso that it reads accurately the diameter of a metal calibrationstandard that is 50.8-mm(2.00-in.)diameter.The Pi tape ismounted on an adjustable plate for calibration.4.2 Weighing Device,accurate to 0.1 g to weigh the bundle.4.3 Graduated,Linear Scale,accurate to 0.5-mm(0.02-in.)to measure the bundle length.4.4 Air Supply,with pressure regulator set for 40 psig.4.5 Calibration Standard,50.8-mm(2.00-in.)in diameter.55.Sampling,Test Specimens and Test Units5.1 The test result depends on the cross-sectional shape,thepolymer,and the length of the bundle selected for the test.Toa lesser extent,it also depends on the filament diameter,sincethin filaments pack more efficiently than large ones.5.2 The device,as pictured in Fig.1,is designed to measurediameters ranging from 30.5 to 52.3 mm(1.20 to 2.06 in.).Make sure that both ends to be measured are within this range.5.3 Calculations are based on conical bundle shape.6.Procedure6.1 Select a sample bundle of approximately 50-mm(2.0-in.)diameter.Filament may be removed from a sample so thebundle diameter falls within the scale range 30.5 to 52.3-mm(1.20 to 2.06-in.).One convenient method to adjust the samplediameter to the desired range is to fill a 50-mm(2.0-in.)insidediameter tube.If the sample is too small,like samples may becombined to adjust the bundle diameter to the desired range.6.2 With rubber bands holding the bundle together,roll itbetween the palms of the hands four times to allow thefilaments to nest.Place the larger end of the bundle inside theloop of measuring tape in the device shown in Fig.2.1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings,Materials,and Applications and is the direct responsibility ofSubcommittee D01.61 on Paint Application Tools.Current edition approved June 1,2017.Published June 2017.Originallyapproved in 2001.Last previous edition approved in 2012 as D6737 12.DOI:10.1520/D6737-12R17.2Air valve such as Model 6676 available from Hunt Valve Co.,1913 E.StateStreet,Salem,Ohio 44460,or equivalent,has been found suitable for this purpose.3Miniature air cylinder such as Model 047 DXP,34in.(19.0 mm)bore 7 in.(178mm)stroke,dual acting,heavy duty available from Bimba Manufacturing Company,Monee,IL 60449-0068,or equivalent,has been found suitable for this purpose.4Pi tape14in.(6 mm)6 ft(1.8 m)with 0.01 in.graduations.Lufkin modelW606P,or equivalent,has been found suitable for this purpose.5Steel cylinder machined to diameter of 2.000 by tolerance(0.001 by 0.001)in.(50.8 by tolerance(0.02 by 0.02)mm).Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued