ASTM F1536-95(2015)e1

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: F1536 − 95 (Reapproved 2015)
Standard Test Method for
Determining Strength and Setting Time of Synthetic Water-
Activated Polyurethane Fiberglass Orthopaedic Casting
Tape
This standard is issued under the fixed designation F1536; 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.
ε NOTE—Editorial corrections were made in June 2016.
1. Scope the peak failure load or the maximum deflection load by the
nominal sample length (that is, manufacturer’s stated tape
1.1 This test method covers the functional diametral com-
width).
pression strength of cylindrical test specimens formed from
3.1.2 maximum deflection load—the test cylinder is com-
synthetic fiberglass polyurethane casting materials. The test
pressed 0.4 in. (10 mm) from the initial load position without
specimens employed in this test method are similar in geom-
noticeable failure or a measurable decrease in load.The load at
etry and construction to casts used in orthopaedic applications.
0.4 in. (10 mm) deflection shall be called the maximum
This test method is not intended to determine the strength of
deflection load.
the base materials used for fabrication of the test specimen.
3.1.3 peak failure load—failure of the test cylinder with a
1.2 The values stated in inch-pound units are to be regarded
concomitantdecreaseinloadpriorto0.4in.(10mm)diametral
as standard. The values given in parentheses are mathematical
compression. The highest load attained prior to the decrease
conversions to SI units that are provided for information only
shall be called the peak failure load.
and are not considered standard.
1.3 This standard does not purport to address all of the
4. Summary of Test Method
safety concerns, if any, associated with its use. It is the
4.1 Atestcylinderispreparedbyimmersingthecastingtape
responsibility of the user of this standard to establish appro-
in 75 6 2°F (23.9 6 1.1°C) water, squeezing per the
priate safety and health practices and determine the applica-
manufacturer’s instructions under the surface of the water, and
bility of regulatory limitations prior to use. Specific warning
thenwrappingaroundeithera2.0in.(50.8mm)or2.5in.(63.5
statements are given in 6.7.
mm)outsidediametercylindricalmandrel.Thetapeiswrapped
layer upon layer producing a five layer cylinder. The test
2. Referenced Documents
cylinder is removed from the mandrel after an initial setting
2.1 ASTM Standards:
period. After a specified time, the test specimen is positioned
E4 Practices for Force Verification of Testing Machines
on its side between two flat platens in the testing machine and
E691 Practice for Conducting an Interlaboratory Study to
compressedtodetermineitsstrength.Ambienttemperatureand
Determine the Precision of a Test Method
humidity are specified because of their pronounced effect on
material properties during the curing period.
3. Terminology
5. Significance and Use
3.1 Definitions of Terms Specific to This Standard:
3.1.1 diametral compression strength—the load per unit
5.1 Diametralcompressionstrengthisanimportantmeasure
width in lbs/in. (Newtons/mm), calculated by dividing either
of the mechanical properties of casting materials. This test
method simulates the loading pattern seen in lower extremity
casting applications during ambulation. This test method can-
This test method is under the jurisdiction ofASTM Committee F04 on Medical
and Surgical Materials and Devices and is the direct responsibility of Subcommittee not be used to determine cast life or measure bending or other
F04.15 on Material Test Methods.
modes of cast failure.
CurrenteditionapprovedMay1,2015.PublishedJuly2015.Originallyapproved
in 1995. Last previous edition approved in 2010 as F1536 – 95 (2010). DOI: 5.2 Thistestmethodmeasuresbutdoesnotprescribevalues.
10.1520/F1536-95R15E01.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or 6. Apparatus
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
6.1 Testing Machines—Machines used for compression test-
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. ing shall conform to the requirements of Practices E4. For
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F1536 − 95 (2015)
universal machines with a common test space, calibration shall ing this include the use of a dead weight clamped to the free
be performed in compression. end of the tape while the horizontally mounted mandrel is
6.1.1 The surfaces of the flat platens shall be perpendicular manually rotated (see Fig. 1), or the use of an automated
to the loading axis and parallel at all times within 0.005 in./in. constant torque winding mechanism (see Fig. 2).
(1.3 mm/mm). Platen surfaces should be clean and free of
6.4 Water Container—A container capable of holding at
corrosion.
least 1 gal (3.78 L) of water and of sufficient depth to allow
6.1.2 The testing machine shall be capable of producing a
complete immersion of the casting tape.
constant compression rate between 1 to 10 in./min (25.4 to 254
6.5 Release Liner—Asheet form liner of nominal thickness,
mm/min).
such as waxed paper, shall be used to cover the mandrel and
6.1.3 The testing machine shall be capable of measuring the
prevent adhesion of the resin to the mandrel. The liner shall
compressive load within 60.5 lbs (2.2 N).
allow release of the cured specimen from the mandrel with
6.2 Test Specimen Preparation Mandrel—A solid, cylindri-
minimal force, and shall be easily removable from the speci-
cal aluminum mandrel of sufficient length to accommodate
men inner diameter prior to compression testing.
three test specimens without end contact shall be mounted in a
6.6 Timer—A timing device accurate to 61s.
horizontal position (see Fig. 1). Either of two mandrel diam-
eters may be used: Type I—2.00 in. (50.8 mm) diameter, or
6.7 Gloves—Gloves capable of protecting the hands from
Type II—2.50 in. (63.5 mm) diameter.
contact with the resin, for example, latex surgical gloves.
6.2.1 Option—Three individual mandrels, either Type I or
(Warning—Contact with uncured or curing resins should be
Type II, each capable of holding one test specimen, may be
avoided.These resins may adhere to the skin and be difficult to
substituted for a single, solid mandrel.
remove. In addition, most polyurethane resins contain isocya-
6.3 Constant Tension Method—Each layer of tape shall be nate to which some individuals are or may become sensitized.
wrapped on the mandrel at a constant tension of 0.25 lbs/in. Gloves should be worn at all times when handling uncured or
(4.5 g/mm) width of tape. Suggested methods for accomplish- curing casting tape.)
FIG. 1 Manual Preparation Method
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F1536 − 95 (2015)
FIG. 2 Automated Constant Torque Preparation Method
6.8 Thermometer—Adevicecapableofmeasuringtempera- 9.6 Wrap a five-ply cylinder on the mandrel as rapidly as
tures within 61°F (0.5°C) in the 70 to 80°F (21.1 to 26.7°C) possible using constant tension (see Fig. 1 or Fig. 2). Each
range. succeeding layer shall be aligned directly over the preceding
layer with complete overlap. Cut the tape at the end of the fifth
7. Reagents and Materials 1
ply within 6 ⁄4 in. (6.4 mm) relative to the starting end of the
first ply.
7.1 Atleastthreerollsofthecastingtapeshallbetested;one
roll for each of the three specified time periods. Three test
9.7 Immediately wrap a second five-ply cylinder as rapidly
cylinders shall be prepared from each roll without the use of
as possible by repeating 9.6.
manual molding techniques.
9.8 Immediately wrap a third five-ply cylinder as rapidly as
NOTE 1—If testing of cylinders with the use of manual molding is
possible by repeating 9.6. Cut off excess tape.
desired, a secondary group of samples should be prepared using the
9.9 Molding—Primary test samples should be prepared
desired molding technique.
without the use of manual molding. If testing of samples with
7.2 Water for initiation of the curing process shall be
the use of manual molding is desired, a secondary group of
maintained at 75 6 2°F (23.9 6 1.1°C).
samples should be prepared using the desired molding tech-
7.2.1 The water shall be changed after three rolls have been
nique. Record the molding time and degree of manipulation
prepared.
used.
8. Sample Conditioning
9.10 Setting Time—This is determined by a manual inden-
tation test, that is, the time elapsed from the initial immersion
8.1 Store each package flat, with each roll on its side, at 70
until the test cylinder cannot be indented by moderate finger-
6 5°F (21.1 6 2.8°C) for at least 24 h before use.
nail pressure. Begin indentation testing for material setting
8.2 Open each package immediately prior to use.
after all three samples from a single roll are wrapped. Repeat
the test every 15 s until all samples are set. Record the three
9. Specimen Preparation
times and report the average as the setting time.
9.1 Beforeopening
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