ASTM D4705
Grip for Double-Hole Stitch Tear Testing of Leather
ASTM D4705 Hydraulic Grip – Universal Grip Data Sheet (PDF)
ASTM D4705 measures how well leather resists tearing at stitch holes, using a specimen with two punched holes that simulate a stitch. It is aimed at lightweight leathers for footwear, apparel and upholstery, where seams are a common failure point. Universal Grip supplies a hydraulic grip that clamps the leather end of the specimen with consistent pressure.
What ASTM D4705 Measures
The test reports the force needed to tear the leather between and beyond two punched holes. One end of the specimen is clamped while a loading member passes through the holes and pulls, tearing the leather much as a stitched seam would fail. The result helps tanneries and product makers judge whether a leather will hold stitching in service. The method applies particularly to lightweight leathers and does not apply to wet blue.
How the ASTM D4705 Test Works
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Cut the specimen and punch the two holes in the geometry your copy of the standard specifies.
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Condition the specimens as required before testing.
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Clamp the solid end of the specimen in the hydraulic grip at the set clamping pressure.
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Pass the double-hole stitch tear attachment through the holes and connect it to the opposite crosshead.
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Pull at a constant rate until the leather tears out, recording the maximum force.
Specimens and Setup
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Cut specimens in the directions the standard or your customer requires, since leather strength varies with direction.
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Punch holes cleanly; ragged holes start tears early and lower results.
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Set clamping pressure high enough to stop slippage but not so high that thin leather is crushed at the jaw.
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Use smooth faces for thin or finished leather and lightly textured faces where slippage is a problem.
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Confirm specimen size, hole spacing and test speed against the current edition of ASTM D4705.
Universal Grip ASTM D4705 Fixture
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Hydraulic clamping gives repeatable, adjustable gripping pressure
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Clamping force independent of operator technique
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Pairs with a double-hole stitch tear attachment for the opposing end
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Smooth or lightly textured faces protect thin leather from jaw breaks
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5 kN standard capacity; higher capacities on request
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Compact steel body with corrosion-resistant finish; clevis pin or threaded adapter
https://www.universalgripco.com/hydraulic-gripsFootwear upper leathers
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https://www.universalgripco.com/astm-d2261Upholstery and automotive leathers
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Tannery quality control
Related Standards and Products
Tell us your leather thickness range, clamping pressure source, capacity and machine connection on our contact page and we will quote a D4705 grip and stitch tear attachment. Request a quote
ASTM D4705 FAQ
Why use a hydraulic grip for a low-force leather test?
Hydraulic clamping applies the same, adjustable pressure every time, independent of who tightens the grip. For leather, that means less slippage on some specimens and fewer crushed jaw breaks on others, so results reflect the leather rather than the clamping.
Does the grip do the whole test?
No. The grip holds the solid end of the specimen. The other end is loaded by a double-hole stitch tear attachment that passes through the punched holes. Order both so the setup is complete.
Which leathers does D4705 cover?
It is particularly applicable to lightweight leathers such as footwear uppers, garment and upholstery leathers. ASTM states that it does not apply to wet blue.
What capacity do I need?
The standard grip is rated at 5 kN, which covers lightweight leathers on an electromechanical frame. Higher capacities are available on request for heavier leathers.
How is double-hole stitch tear different from a tongue tear test?
A tongue tear test, such as ASTM D2261 for fabrics, propagates a tear from a cut slit. D4705 tears the leather from two punched holes, which more closely represents a stitched seam pulling through the material.