View Full Version : Cutting Carbon Fibre

11-04-2012, 01:50 AM
Do any of you have experience milling carbon fibre pultrusions? I'm thinking about this 10mm box section (http://www.easycomposites.co.uk/products/carbon-fiber-section/carbon-fibre-box-section-10mm-8mm.aspx), and would like to do some mitres and bits. I know it is very stiff, but is it also very hard? Any tips I might need to know? What does it compare to for difficultly in milling; plastics, aluminium, steel?


John S
11-04-2012, 01:54 AM
It's immensely abrasive, shags cutters up like no tomorrow, carbide included.
I think the pro's use diamond coated tooling for it.

11-04-2012, 10:57 AM
I think the pro's use diamond coated tooling for it.

Does that make me a pro :untroubled:

I've cut carbon fibre sheet lots of times. By far the best cutter I found is those cylindrical diamond coated cutters you find in rotary tool kits:

http://www.ebay.co.uk/sch/i.html?_trkparms=65%253A12%257C66%253A2%257C39%253 A1%257C72%253A6239&rt=nc&_nkw=diamond+burr&_trksid=p3286.c0.m14&_sop=15&_sc=1

Here's a video of one of these cutting:

[Ok can't find that, will post when I have]



It's a bit slow (300mm/min @24000rpm if I recall correctly), but the cutters last a long time and since it's effectively a grinding process the finish is excellent.

01-05-2012, 08:17 PM
A chap who does alot with this stuff told me it kills electric spindles very quickly? The 'dust' being very effective at destroying electrical bits....? Anyone had experience of this?

02-05-2012, 10:45 PM
What sort of spindle is there other than electric? Steam?

02-05-2012, 11:40 PM
What sort of spindle is there other than electric? Steam?

:beaten: hehe, I should have said air cooled VS water cooled :)

The chap thought water cooled would have been much less effected..

03-05-2012, 12:05 AM
Ahh I see. He probably has a good point, I'll try to avoid letting the dust get about. I'll be using a water-cooled spindle anyway.

Anónio Pinho
18-05-2012, 12:17 AM
Good night:

To cut carbon fiber with a perfect finish, watch the video.
Spindle speed 9250 rpm ...
Feed Rate ..... 920 mm / m
Rate Plunge ..... 550 mm / m
Two blade .... End Mill 3 mm

Carbon Fiber .... Thickness .... 1.5 mm


Good Works.
António Pinho


18-05-2012, 02:21 AM
Did you find the end-mill became blunt quickly? Was it an uncoated endmill?