SLS vs. CNC Machining for Functional Prototypes

Introduction

Both SLS and CNC machining are used for functional prototypes, but they solve different problems. CNC is strong when exact machined geometry and dense material behavior matter most. SLS is stronger when speed, geometry freedom, and design iteration matter more.

Where SLS Has the Advantage

• Faster iteration on complex shapes
• No tooling or fixturing burden for unusual geometry
• Better for internal channels and lightweight forms
• Easier path into low-volume nylon production

Where CNC Still Wins

• Tight machined tolerances
• Solid billet materials
• Metal part simulation
• Very smooth precision surfaces on selected features

Final Takeaway

Choose CNC when the prototype must behave like a machined part. Choose SLS when the prototype needs to answer broader functional and design questions faster.