End Mill Comparisons in CFRP, Part 3 - Conventional PCD Tool

Smith MegaDiamond Inc. and Star Cutter Company compared the performance of various end mills in carbon fiber reinforced plastic (CFRP). The tools tested included a coated carbide end mill, a diamond-coated end mill, a conventional PCD end mill with straight flutes, and a “veined” PCD end mill featuring a vein of PCD within a helical slot in a carbide tool body.

The table below summarizes the test parameters. Shown here is the video of a straight-flute segmented PCD tool. Jeff Michael, engineering manager for Star Cutter, comments, “Notice the sound includes pounding. This is the effect of the cutter loading and unloading because of the straight flutes. Also, there are uncut fibers because of the lack of shearing geometry.”

To see the next video in this testing, click here.

 

 

	Tool Type
Ø .500 in.	Solid Carbide	CVD Diamond	PCD	Veined PCD
Flute angle	30° helical	10° helical	7° skew	30° helical
Spindle speed (rpm)	3,000	4,600	12,000	18,000
Chip load (in./tooth)	0.0035	0.0035	0.001	0.0065
Machine advance (in./min.)	42	64	36	470
Radial depth (in.)	.050	.050	.050	.050

Cutting speeds and feed rates were recommended parameters from each tool’s manufacturer.

 

Editor’s note: To read the next part in the series, click here.