01Jaw Width and Opening
Jaw width determines the size of workpieces you can grip and how evenly force distributes across them. A 2″-5″ light-duty vise suits hobby and small work; 6″-8″ medium-duty covers most workshop and auto repair tasks; 8″-10″ heavy-duty handles industrial fabrication.
Opening (maximum gap between closed and open jaws) must exceed your largest workpiece. Measure your biggest material before choosing.
02Clamping Force
Clamping force — 1200-1500 lbs for light-duty up to 6000-8000 lbs for heavy-duty — determines what the vise can hold under work pressure. Beyond a point, more force can damage delicate workpieces, so match force to application.
Reputable manufacturers publish clamping force per model, measured under controlled torque. Ask for it when comparing OEM suppliers.
03Body Material: Cast Iron vs. Forged Steel
Gray cast iron (HT200/HT250) resists compression and is economical — the standard choice for light to medium vises. Forged or cast carbon steel (45#) adds tensile strength and impact resistance, essential for heavy-duty and shock-load applications.
Jaw faces are hardened separately (58-62 HRC) so the gripping surface outlasts the body. Replaceable jaw inserts extend service life. For the full mechanical picture, see the cast iron vs. forged steel comparison.
04Swivel Base and Mounting
A 360° swivel base repositions work without unbolting — ideal for shops that change work angles. A fixed base is more rigid for heavy hammering and is simpler and cheaper.
Mounting matters too: match bolt size and spacing to your workbench, and reinforce the top for heavy-duty vises. A thin, soft bench defeats an otherwise good vise.