EPN-F solid endmills for machining CFRP and honeycomb parts

The increased popularity of composites in aerospace applications creates new challenges for shops that are used to cutting metal. One of these substances, Carbon Fiber-Reinforced Plastic (CFRP), can be especially difficult to machine.

These materials are extremely abrasive and difficult to machine, as a result of the different physical properties of the materials used in the layers that make these composites hard, tough and strong. Due to the harsh cutting environment, tool life can be very short when machining CFRP composites. As the exact formula of what these composites are made from is not known, it can be difficult to design appropriate tools. Much of Iscar’s R&D resources are spent on solving the problem of machining these complex materials.

When machining composites such as CFRP – there is no chip to speak of. Instead, the material removal mechanism might be better described as shattering. The impact of the cutting edge fractures the hard carbon fibres, instead of shearing material away.


This process causes the cutting edge considerable abrasion that can lead to rapid wear. In composite machining, as well as any cutting tool application, tool geometry drives cutting performance. However, in composites, tool material also becomes a driver of performance. Unless the edge material can withstand the abrasion well enough to hold its geometry and stay sharp, the tool can wear so rapidly that the geometry can change rapidly as well.
In order to successfully machine CFRP, Iscar offers hard, sharp solid-carbide tools made from grade IC02 which can be supplied on request with long-lasting diamond coating (IC2018).

The fixture for machining a composite part can be a considerable engineering investment. Clean cutting without fraying, delamination or otherwise separation of the layers, requires the part to be firmly secured against vibration.

EPN-F Endmill Features
• Fine pitch – 10 and 12 flute endmills
• Unique flute profile provides good surface finish
• In most cases, eliminates CFRP fibre breakout
• Reduces delamination
• Decreases cutting forces
• Available in diameters 3-12 mm
• Available in IC02 uncoated or diamond coated – on request

CFRP has become the industry standard widely used in the aerospace and aviation industries and also for advanced mechanical parts, and can be used in a large variety of relevant applications.

Lighter and stronger than ever, the new breed of carbon fiber reinforced plastics and laminates are elevating performance levels in applications ranging from downhill skis and tennis rackets to military aircraft and automobiles.

Composites technology can help automakers reach their light weighting goals faster than carbon fiber-reinforced plastics. For full details and to view the video visit, please click HERE.

For further details contact Iscar South Africa on TEL: 011 997 2700 or visit www.iscar.com