What real tolerances do you get with metal laser cutting?

Laser cutting equipment specifications often indicate tolerances of ±0.1mm or even tighter. But what you achieve in practice depends on several factors.

Factors influencing real tolerance

1. Material thickness Thinner materials (under 3mm) allow tighter tolerances — thermal movement is less. At large thicknesses (8–12mm), thermal distortions appear that extend practical tolerances.

2. Material - Carbon steel: predictable behavior, practical tolerances ±0.15–0.2mm - Stainless steel: similar to steel, slightly more predictable with nitrogen - Aluminum: high thermal conductivity — larger variations possible

3. Part geometry Parts with fine details (small holes, tight slots) or complex geometries have less precise tolerances at geometric extremes.

4. Cutting parameters Speed, power, gas and focus all influence edge quality and precision.

What is realistic to expect

For normal industrial applications: - ±0.15–0.2mm on simple parts from thin material - ±0.2–0.3mm on complex parts or thick materials

For tighter tolerances (±0.1mm or better), you need: - Material-specific optimized parameters - Verification and sorting per part - Possibly additional finishing operations

Design implications

If you are designing a part that requires a precise fit, check with the supplier for real tolerances before finalizing the drawing. Sometimes a small design change eliminates the need for tight tolerances.