Best End Mills for Acrylic & Plastic CNC Cutting

Acrylic and plastic materials require sharp cutting tools designed to produce clean edges while preventing melting or chip buildup. Choosing the correct CNC end mill is important for achieving smooth finishes and reliable machining.

Plastics behave differently from metals when machined. Instead of producing small chips like aluminum or steel, plastics tend to soften with heat. For this reason, tools designed for plastics focus on efficient chip evacuation and reduced friction.

Common End Mills Used for Plastic Machining

  • Single-flute O-flute end mills for optimal chip evacuation
  • Single-flute plastic cutting end mills with specialized flute geometry
  • Two-flute carbide end mills for general plastic machining
  • Micro end mills for engraving and very small features

Single-Flute (O-Flute) End Mills

O-flute end mills are one of the most common tools used for machining acrylic and plastics. Their large flute space allows chips to evacuate efficiently, which helps prevent melting and produces smooth edge finishes.

These cutters are commonly used for machining materials such as acrylic (PMMA), polycarbonate, PVC, HDPE, ABS, and Delrin.

The single-flute geometry removes chips quickly while reducing heat buildup in the cutting zone, making them ideal for many CNC router applications.

Browse available tools:
Shop O-Flute End Mills

Single-Flute Plastic Cutting End Mills

Some tools designed for plastic machining use a single-flute geometry that differs from a traditional O-flute. These cutters often incorporate specialized flute shapes, higher helix angles, or chip-breaking features that improve chip evacuation and reduce friction during cutting.

For example, certain plastic cutting end mills feature a high helix angle and polished flute surface that helps prevent plastics from melting while producing clean edges when machining acrylic and similar materials.

These tools are commonly used for machining:

  • Acrylic (PMMA)
  • Polycarbonate
  • PVC
  • ABS
  • Engineering plastics

Example plastic cutting tool:
1/16" Single-Flute End Mill for Acrylic & Plastics

Two-Flute Carbide End Mills

Two-flute carbide end mills can also be used for plastic machining. While they do not evacuate chips as aggressively as single-flute tools, they can perform well when machining thinner plastic sheets or performing general-purpose routing operations.

They are commonly used for:

  • Light profiling
  • General CNC routing
  • Thin plastic sheet cutting

Browse two-flute tools:
Shop Two-Flute Carbide End Mills

Tips for Machining Acrylic and Plastics

  • Use sharp carbide cutting tools designed for plastics.
  • Ensure good chip evacuation using air blast or vacuum extraction.
  • Avoid excessive heat buildup which can cause plastics to melt.
  • Use appropriate spindle speeds and feed rates for the material.
  • Keep cutting edges clean and free of plastic buildup.