Knife Operation Notices

Blade Alignment & Collet Installation

  • Centerline & Projection Setup
    • Insert the blade into the collet or adapter holder so that the cutting edge faces strictly along the tool holder's reference zero axis.
    • Set blade extension so that the exposed length equals material thickness plus 0.5 mm to 1.0 mm into the sacrificial cutting mat. Excessive extension increases lateral blade deflection and premature wear.
  • Clamping & Collet Inspection
    • Inspect collet slits and clamping screws for debris or metal fatigue before insertion. Tighten holding set-screws uniformly against the blade shank flat to prevent the blade from twisting out of square under lateral load.
  • Angle Verification
    • Ensure the blade back is square to the worktable. If using asymmetric bevel blades, verify whether the vertical face should run toward the finished cut or the scrap side.

Tangential Calibration & Directional Tuning

  • Theta-Axis (Rotational) Zero Calibration
    • Perform a straight test cut along the machine's primary X-axis.
    • If the blade drifts, crabs, or cuts diagonally during an X-only move, adjust the tangential C/Theta-axis software zero offset until the blade runs strictly parallel to the motion vector.
  • Blade Offset & Turning Radius
    • Calibrate the tool center point (TCP) offset. The tip of a trailing blade sits slightly behind the rotational centerline; calibrate this offset value in your CAM/CNC controller so corners do not tear or round over.
  • Corner Lift & Overcut Management
    • For dense materials (thick rubber, high-density foam, gasket sheets), enable lift-and-rotate at sharp corners (angles tighter than 30°–45°) to prevent corner tearing caused by rotating the blade while fully buried in the cut.
    • Set appropriate lead-in/lead-out overlaps (typically 0.5 mm – 1.5 mm) to ensure complete part separation without leaving tabs.

Vacuum Hold-Down & Underlayment Requirements

  • Sacrificial Cutting Mat Selection
    • Always place a specialized, air-permeable sacrificial mat (e.g., breathable felt, fibrous cutting mat, or porous sacrificial board) over the vacuum zones. A standard MDF spoilboard causes rapid blade dulling and restricts airflow required for thin, flexible materials.
  • Zone Masking & Sealing
    • Expose vacuum flow strictly beneath the workpiece. Use scrap acrylic, PVC, or masking film to seal unused perimeter vacuum zones. Flexible materials like corrugated cardboard, open-cell foam, and textiles lift instantly if vacuum pressure drops across unsealed table areas.
  • Material-Specific Hold-Down Tactics
    • Textiles and Porous Foams: Lay thin masking plastic or release film over the top surface. The vacuum draws through the open cells and pulls the film down tightly against the top face, dramatically increasing hold-down force.
    • Thin Rigid Foams and Corrugated Boards: Verify that vacuum pump pressure maintains at least -70 to -85 kPa (-20 to -25 inHg) during the cut to resist the vertical lifting forces generated by oscillating stroke up-action.

Stroke, Pressure, and Feed Guidelines

  • Oscillating Cutting Heads: Match stroke frequency and forward feed rate so the blade fully shears the material without dragging. Feed rates that outpace oscillation frequency cause blade deflection, serrated edge finishes, and broken blade tips.
  • Pneumatic Heads: Maintain steady regulated dry air (typically 6 to 8 bar / 85 to 115 PSI, depending on unit spec) to prevent stroke hesitation in dense or fiber-reinforced stocks.