ASTM D4786-00(2016)

Standard Test Method for Stitch Tear Strength, Single Hole

SIGNIFICANCE AND USE
3.1 This test method is intended to be used to rate leathers as to their stitch tear strengths.
SCOPE
1.1 This test method is intended for determining the stitch-tearing strength of leather with a tear originating from one hole. It is particularly applicable to heavy leather. This test method does not apply to wet blue.  
1.2 The values stated in inch-pound units are to be regarded as standard. No other units of measurement are included in this standard.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 31-Aug-2016
• ICS: 59.080.30 - Textile fabrics
• Technical Committee: D31 - Leather
• Drafting Committee: D31.01 - Vegetable Leather

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D4786 − 00 (Reapproved 2016)
Standard Test Method for
1
Stitch Tear Strength, Single Hole
This standard is issued under the fixed designation D4786; 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 4.5 Testing Machine, power-driven, as described in Test
Method D2209.
1.1 This test method is intended for determining the stitch-
tearing strength of leather with a tear originating from one
5. Test Specimen
hole. It is particularly applicable to heavy leather. This test
5.1 The test specimen shall be a rectangular piece of leather
method does not apply to wet blue.
1 in. by 2 in. die cut from the sample unit of leather. The end
1.2 The values stated in inch-pound units are to be regarded
of the specimen in which the hole is to be punched shall be at
as standard. No other units of measurement are included in this
least 1 in. away from any uncut edge on the unit. The direction
standard.
of the long axis relative to the backbone shall be noted.
1.3 This standard does not purport to address all of the
6. Procedure
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
6.1 Place the specimen on the anvil of the thickness gage
priate safety and health practices and determine the applica-
and lower the presser foot gently (do not drop) until it rests on
bility of regulatory limitations prior to use.
the specimen.Take the reading 5 s after the full load is reached.
Read the thickness to the nearest 0.001 in. The thickness of the
2. Referenced Documents
specimen should be taken on the long axis near the end in
2
2.1 ASTM Standards:
which the hole is to be punched.
D1813 Test Method for Measuring Thickness of Leather
1
6.2 Punch a ⁄8 in. diameter hole on the long axis of the
Test Specimens
5
specimen. The center of the hole should be ⁄32 in. from the end
D2209 Test Method for Tensile Strength of Leather
on which the thickness was measured.
3. Significance and Use
6.3 Grip the yoke in one of the testing machine jaws. Place
the end of the specimen containing the hole between the arms
3.1 This test method is intended to be used to rate leathers
of the yoke and pass the steel rod through the holes in the yoke
as to their stitch tear strengths.
and the specimen. Clamp the free end of the specimen in the
4. Apparatus
other testing machine grip. Operate the machine at 10 6 2 in.
per minute until the specimen starts to tear. At the instant that
4.1 Thickness Gage—A dead-mass type of thickness gage,
tearing begins, note and record the load registered by the
as described in Test Method D1813.
machine.
4.2 Steel Punch, beveled on the outside, which will make a
1
⁄8 in. diameter hole.
7. Calculation
4.3 Metal Yoke, made to the dimension shown in Fig. 1.
7.1 Calculate the pounds per in. thickness as follows:
F = lb at initial tear Stitch tear strength = F/T
4.4 Steel Rod, 0.095 6 0.005 in. in diameter and at least 1
F/T
T =
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D4786 − 00 (Reapproved 2010) D4786 − 00 (Reapproved 2016)
Standard Test Method for
1
Stitch Tear Strength, Single Hole
This standard is issued under the fixed designation D4786; 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
1.1 This test method is intended for determining the stitch-tearing strength of leather with a tear originating from one hole. It
is particularly applicable to heavy leather. This test method does not apply to wet blue.
1.2 The values stated in inch-pound units are to be regarded as standard. No other units of measurement are included in this
standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2
2.1 ASTM Standards:
D1813 Test Method for Measuring Thickness of Leather Test Specimens
D2209 Test Method for Tensile Strength of Leather
3. Significance and Use
3.1 This test method is intended to be used to rate leathers as to their stitch tear strengths.
4. Apparatus
4.1 Thickness Gage—A dead-mass type of thickness gage, as described in Test Method D1813.
1
4.2 Steel Punch, beveled on the outside, which will make a ⁄8 in. diameter hole.
4.3 Metal Yoke, made to the dimension shown in Fig. 1.
4.4 Steel Rod, 0.0956 0.095 6 0.005 in. in diameter and at least 1 in. long.
4.5 Testing Machine, power-driven, as described in Test Method D2209.
5. Test Specimen
5.1 The test specimen shall be a rectangular piece of leather 1 in. by 2 in. die cut from the sample unit of leather. The end of
the specimen in which the hole is to be punched shall be at least 1 in. away from any uncut edge on the unit. The direction of the
long axis relative to the backbone shall be noted.
6. Procedure
6.1 Place the specimen on the anvil of the thickness gage and lower the presser foot gently (do not drop) until it rests on the
specimen. Take the reading 5 s after the full load is reached. Read the thickness to the nearest 0.001 in. The thickness of the
specimen should be taken on the long axis near the end in which the hole is to be punched.
1 5
6.2 Punch a ⁄8 in. diameter hole on the long axis of the specimen. The center of the hole should be ⁄32 in. from the end on which
the thickness was measured.
1
This test method is under the jurisdiction of ASTM Committee D31 on Leather and is the direct responsibility of Subcommittee D31.01 on Vegetable Leather.
Current edition approved April 1, 2010Sept. 1, 2016. Published May 2010September 2016. Originally approved in 1988. Last previous edition approved in 20052010 as
D4786 – 00 (2005).(2010). DOI: 10.1520/D4786-00R10.10.1520/D4786-00R16.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Serv
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