Plasma Cutting Speed Calculator

Calculate optimal cutting speed for plasma arc cutting based on amperage and material.

Cutting Capacity by Amperage

Amperage Quality Cut Sever Cut
45A6mm (1/4")12mm (1/2")
65A12mm (1/2")19mm (3/4")
85A16mm (5/8")25mm (1")
130A25mm (1")38mm (1.5")
200A38mm (1.5")50mm (2")
300A50mm (2")75mm (3")

Plasma Cutting Fundamentals

Speed Selection

Optimal cutting speed balances cut quality against productivity. Too slow = excessive dross, too fast = incomplete cuts. The "quality window" is typically 80-100% of maximum rated speed.

Signs of Incorrect Speed

  • Too Slow: Low-speed dross on bottom, excessive top edge rounding, wider kerf
  • Too Fast: High-speed dross, arc trails backward, incomplete penetration
  • Correct Speed: Vertical drag lines, minimal dross, clean bottom edge

Gas Selection Guide

  • Mild Steel: Oxygen plasma / Air shield - best edge quality and speed
  • Stainless Steel: N2 or H35 plasma / N2 or CO2 shield - prevents oxidation
  • Aluminum: N2 or Ar/H2 plasma / N2 shield - cleaner cuts
  • Air/Air: Economical for mild steel, acceptable quality