Wednesday, February 7, 2024

Milling Carbon Fiber Composite

I showed you how I clamped down that 6" x 6" x 3/8" plate of material.  Then I used the 1/8" carbide end mill to slice a 1.125" x 6" slice.  I do not think that I clamped it down right enough or perhaps 1"/minute was too fast and it rotated slightly on the table.  So I had to the workpiece (both the 1" slice and the remainder) vertically in the mill vise and square both of them with my 3/4" HSS end mill.  I cannot see or feel that it has lost its sharpness, but I think that for these sort of facing operations, I should buy a large diameter carbide end mill.

Did the 1" slice come out a size that will make the dust caps (really fillers) for the 1" rectangular tubes.  It slides in either dimension with enough pressure that it will stay in place while I turn 6-32 screws into the edges.


  1. I used to work on the 787. Carbon fiber is hell on steel tooling. Carbide is the way to go, however beware of the dust. Also, keep speeds slow so that you don't melt the epoxy binder. Lubricants can serve dual purposes there.

    1. Yes. I wear thick surgical gloves, an N95 mask (COVID has one benefit) and I run the shop vac continuously to grab dust from air and work area.

    2. Be sure the filter on the shop-vac is HEPA quality.