ASTM D4786-00

Standard Test Method for Stitch Tear Strength, Single Hole

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 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: 09-Sep-2000
• ICS: 59.080.30 - Textile fabrics
• Technical Committee: D31 - Leather
• Drafting Committee: D31.01 - Vegetable Leather

Relations

• Replaced By: ASTM D4786-00(2005) - Standard Test Method for Stitch Tear Strength, Single Hole
• Effective Date: 01-Sep-2005

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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
Standard Test Method for
Stitch Tear Strength, Single Hole
This standard is issued under the fixed designation D 4786; 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 (e) indicates an editorial change since the last revision or reapproval.
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 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 appro-
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use.
2. Referenced Documents
2.1 ASTM Standards:
D 1813 Test Method for Measuring Thickness of Leather
Test Specimen
D 2209 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.
FIG. 1 Metal Yoke
4. Apparatus
4.1 Thickness Gage—A dead-mass type of thickness gage,
6. Procedure
as described in Test Method D 1813.
6.1 Place the specimen on the anvil of the thickness gage
4.2 Steel Punch, beveled on the outside, which will make a
and lower the presser foot gently (do not drop) until it rests on
⁄8in. diameter hole.
the specimen.Take the reading 5 s after the full load is reached.
4.3 Metal Yoke, made to the dimension shown in Fig. 1.
Read the thickness to the nearest 0.001 in. The thickness of the
4.4 SteelRod, 0.0956 0.005 in. in diameter and at least 1 in.
specimen should be taken on the long axis near the end in
long.
which the hole is to be punched.
4.5 Testing Machine, power-driven, as described in Test
6.2 Punch a ⁄8in. diameter hole on the long axis of the
Method D 2209.
specimen. The center of the hole should be ⁄32 in. from the end
on which the thickness was measured.
5. Test Specimen
6.3 Grip the yoke in one of the testing machine jaws. Place
5.1 The test specimen shall be a rectangular piece of leather
the end of the specimen containing the hole between the arms
1 in. by 2 in. die cut from the sample unit of leather. The end
of the yoke and pass the steel rod through the holes in the yoke
of the specimen in which the hole is to be punched shall be at
and the specimen. Clamp the free end of the specimen in the
least 1 in. away from any uncut edge on the unit. The direction
other testing machine grip. Operate the machine at 10 6 2 in.
of the long axis relative to the backbone shall be noted.
per minute until the specimen starts to tear. At the instant that
tearing begins, note and record the load registered by the
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