Routing Carbon fibre laminate

[kong]

Just wondering if anyone has any experience on this? I've just laminated some, and should be ready to go on wednesday. It will be about 1 - 1.5mm thick, and I intend to use 1/16" endmills to cut it. All advice is welcome.

[CNCadmin]

I cut 1/8", 1/16" thick G-10 with a 1/16" and 1/8" bit no probelm, just make sure you use somthing to suck the dust as it cuts. Also don't run a high feed rate or your bit will flex at least mine did.

[Rekd]

Paul, I've machined carbon fiber before, it chipped quite easily. Do you notice this when routing it also? Use different tool geometry?

'Rekd teh curious

[CAMmando]

Much more abrasive than Glass. Polychrystaline diamond tipped cutting tools provide the best tool life (with the obvious downside of cost and availability. If cutting is limited carbide will work. YOU DO NOT WANT TO BE BREATHING THE DUST !! Good Dust Collection and a mask are advisable. Since cutting fluids are usually a no-no, you may want to try "Boe Lube". It is available from MSC in various forms. It is a lubricant that will extend tool life and does not hurt laminated composite materials. It was developed by Boeing for this purpose. Often carbon fiber laminites are laid up so that a layer of glass cloth is on the outer surfaces. This helps protect the carbonfiber, provides some protection against galvinic corrosion of adjacent parts, and helps prevent splintering of the carbon fibers (particularly if the carbon fiber is unidirrectional tape). In anycase, try to use cutter geometries and toolpathing approaches that will best guard against delamination. If the parts are flat and delamination is a problem, consider sandwiching between sacrifficial sheets. Also if you are cutting alot, consider variable depthof cut (ramping or stepping down) to prolong life of the cutting.

CAM teh run-on paragraph

[CNCadmin]

Originally posted by Rekd
Paul, I've machined carbon fiber before, it chipped quite easily. Do you notice this when routing it also? Use different tool geometry?

'Rekd teh curious

I have a pic of frames I cut, and I did have any problem with chiping. My cuts where very clean.

[kong]

Thanks guys, some useful stuff! I have not got dust collection sorted out yet, but my machine is in a box so it won't be a problem.......until cleanup time!I like the idea of sandwiching it between sacrificial layers, if chipping is a problem, but I'll wait and see first. I guess I'm have to buy me some solid carbide cutters now though! Any chance of that picture cncadmin?

[CAMmando]

Try Looking Here


http://starliteindustries.com/designs.htm

[kong]

Thanks for the info, unfortunately I'm in the UK, so I'll have to find something closer to home. It will obviously be worth forking out for the diamond tipped tooling, but I'm just so eager to go!

[kong]

Cammando, I have bee nlooking at various cutters on the net, but the price of those PCD ones are ridiculous over here! About £170 for one ($250). So I would like your opinions on these two:
diamond end mills - if the link doesn't work, goto the shop and then to "diamond" cutters (please!)
solid carbide burrs
Having just spent around $100 to get some decent aluminium cutters, I am a bit broke at the mo, and don't have spare cash to test different cutters. i tried a standard FC3 cutter on the carbon, and i got slite splintering. Apart from that, it was OK. Your advice is appreciated.

[sorincnc]

Kong,
I never had anyproblems with the suff shreading or comming apart. Tool life is not that good.. Make sure that you use carbide tooling. If high speed tools are used they heat up and there comes the problems. Diamond coated tools are the best but extremely expensive. What I have found is that small router bits (1/16 )are easy to find at hardware stores (IE lowes and Home Depot in the dremel tools area). They sell a carbide bit that has diamond shaped bumps on it (looks like a rasp) instead of flutes. That is actually pretty good because it actually grinds through the material rather than cutting it. You might ask what I am doing buying tools at home depot.....well one Sunday afternoon the last bit broke and I had to finish the job so there I was. Please do your self a big favor. Check the material safety data sheet. This stuff is very nasty to your health if not using the proper vacum and mask. Do NOT mess with it unless you can protect your self from breading it.
Regards,
Sorin

PS: If you want to know anything there is to be known about machining CF look up one of the members here. His name is Mark Linder and he is the GOD of machining CF.

[HuFlungDung]

Thanks for that warning about carbon fibre, Sorin. I've never had to cut any yet, but there's always a first time and it's nice to know whats hazardous beforehand.

[sorincnc]

GEEEE Murray,
Is almost 2AM and there we are, tho only ones holding down the fort...Or is it 11 PM for you. I must be addicted or something. I am suppossed to be on vacation and not doing this.....LOL
The wonderfull efects of the jawa bean.
Good Night my friend,
Sorin