The best jaw face is the one that holds your specimen securely through the entire test without introducing slip, crushing, or unwanted surface damage. In practice, you are balancing grip traction against how sensitive the specimen surface is.

Key inputs that typically drive jaw face selection include:

• Material hardness and ductility, including how easily it will indent or neck in the grip area
• Surface condition, such as smooth, coated, oxidized, or textured
• Specimen geometry, including thickness, width, and whether it is flat, round, or irregular
• Required load level and how much clamp force is needed to prevent slip
• Risk tolerance for jaw marks versus the need for high holding power

As a starting point, smooth faces are often used when you want to minimize marking, serrated or knurled faces are common for higher-traction gripping on tougher materials, and rubber-coated faces can help with softer or lower-friction specimens. The grip style and test method can also influence what works best for repeatability.

If you want to confirm the right jaw face and grip configuration for your material and specimen geometry, review the options under learn more or request a quote.