End mill for composites introduced by Sandvik Coromant

This minimizes any potential for splintering, a common defect when machining CFRP and several other types of engineering composites using higher helix cutters.

Edge milling
The new Plura end mill has been designed for edge milling applications on workpieces with a minimum thickness of 6 mm. It features optimized micro geometry that offers six effective cutting edges for achieving a surface finish of well below 4 µm, in combination with high material removal rates. Users should keep the split-line in the middle of the material for best results. Also, remember that when the tool cuts across the fibres on the top or bottom surface there is more splintering than when the tool cuts along the fibre direction.

Conventional up-milling strategies are recommended as these typically deliver less vibration. Among the cutting data users can expect to see is cutting speeds of 200-400 m/min, and feed rates of 0.03-0.06 mm/tooth for roughing (0.02–0.04 mm/tooth finishing).

Cross-sector appeal
Aside from the aerospace industry, other sectors set to benefit from the new end mill include motorsport, marine, wind energy and leisure – essentially any company machining CFRP that is looking to enhance material removal rate and tool life while at the same time achieving minimal splintering.

The CoroMill Plura compression end mill for composites makes use of GC1630 grade for extended life, and comes in diameters ranging from 6.0 to 16.0 mm, and lengths (total) from 76 to 100 mm.