Workholding Best Practices for CNC Production

Workholding limits production speed more than tooling for many shops. Modern systems cut setup time 50-80% and improve repeatability.

Workholding Categories

• Manual vises (Kurt, Gerardi) — Foundation for prototype and short runs
• Power vises (Schunk, Jergens) — Hydraulic or pneumatic, faster cycling
• Soft jaws — Custom-machined to part profile, max grip
• Pallet systems (Erowa, System 3R, Lang) — Rapid changeover, zero-point
• Vacuum tables — For thin sheet, panels, plates
• Magnetic chucks — Steel and cast iron flat work
• Fixtures (custom) — Production parts, dedicated setup

Zero-Point Clamping ROI

Erowa, Lang Quick-Point, System 3R, Schunk VERO-S — all use the same idea: standard pallets locked into base plates with sub-2-second changeover and ±5µm repeatability.

For shops with 20+ setups/day, system pays back in 6-12 months via reduced setup time. For lights-out production, essential.

Vise Soft Jaw Tips

• Machine soft jaws while clamped on a parallel (pre-loads jaw consistent with cutting force)
• Use carbide-tipped jaws for hardened materials above 30 HRC
• Stamp part number on each jaw set for production reuse
• Replace soft jaws annually in production (wear reduces grip)

Workholding Force Calculation

Required clamping force = (Cutting force × safety factor 2-3) ÷ friction coefficient

For typical milling: 2 kN cutting force × 2.5 safety / 0.15 friction = 33 kN clamping force needed. A modern 6″ power vise delivers 35-50 kN — adequate.

Fixture Material Selection

• Aluminum 6061 — Light, machinable, OK for most CNC milling fixtures
• Cast iron — Heaviest, dampens vibration, best for grinding/precision
• Steel 1045 — Stronger than aluminum, common for production fixtures
• Tool steel A2 — For wear-resistant fixtures (high-volume)

Browse our tool holders and contact us for custom fixture sourcing.