Carbon Fibre and CNC

[Tuna]

I'm vaguely looking at getting some carbon fibre parts made - just beginning to explore Fusion 360 to see if I can design stuff. I'm looking at 3-5mm sheet, structural rather than cosmetic for small (typically less than 250mm) lightweight components.

So one question is - is anyone aware of reasonably priced cutting services that can do prototype runs as well as small production? Ideally bevelled edge as this would be a 'consumer' product. It might also be interesting to use bent sheet, but I have no idea what's possible without things getting complicated (and therefore expensive).

The other possibility this leads to is buying a benchtop CNC machine - as this might also allow for experiments in small scale prototyping, in aluminium, wood and carbon fibre. A quick review of the market seems to suggest there are 'hobbyist' machines, some of which claim to be able to handle aluminum stock. However, the YouTube videos from actual users seem to imply that they need nursing through such jobs and are probably huge time sinks. Unfortunately, the 'non-hobbyist' stuff costs at least five times as much, and the conversation turns to people who talk in terms of minimal order quantities that are measured in tons. Is there any middle ground here?

[spikeyhead]

The middle ground is a second hand machine.

The little ones aren't rigid enough to machine anything properly.

[oddball1313]

I might be able to help in terms of supplying a machine or pointing you towards people who might machine parts for you, where in the country are you?

[Tuna]

East Anglia - Near Cambridge. The rational part of me tells me that finding a good cutting service is far more sensible than buying something that will probably only be used a handful of times.

[oddball1313]

To give you a few figures, youre looking at around £10-£12k for something like a 10-12 year Haas minimill. You’ll need tooling, a compressor and training so probably another £3k on top of that. If you’re going to programme offline onecnc is a good starter Cad/cam system, i think that is £2-3k off the top,of my head. If you want a few good small good quality cnc shops drop me a message and i can give you contact details of a few companies i supply (what size parts do you need to machine?)

[Tuna]

oddball1313 said:

To give you a few figures, youre looking at around £10-£12k for something like a 10-12 year Haas minimill. You’ll need tooling, a compressor and training so probably another £3k on top of that. If you’re going to programme offline onecnc is a good starter Cad/cam system, i think that is £2-3k off the top,of my head. If you want a few good small good quality cnc shops drop me a message and i can give you contact details of a few companies i supply (what size parts do you need to machine?)

Yes, that's way overblown for my application - think more precision model making than car parts. As I said, I'm looking at decent grade carbon fibre sheets - 5mm max, with parts up to 250mm x 200mm tops.

[rich888]

For prototyping have you considered 3D printing the items, there are plenty of companies that can print from your files. Try the likes of www.shapeways.com for an idea of prices.

[Tuna]

I have a 3D printer (thinking about getting another one). Unfortunately, I need more structural strength than it will give me to test the parts I am designing. Hence the need for carbon fibre (or aluminium in some cases).

Frankly, at 10K for a second hand machine there's no way I can justify that sort of investment - it would need me to produce thousands of components to recoup the investment, which makes running the machine a full time job in itself.

[Insurancejon]

you know you can get stuff 3d printed in some quite interesting alloys now?

[Insurancejon]

my pal it the head of the new division running it at uddehome. they can arrange the printing as well as supplying the metal

[egroeg]

Maybe try get someone to print sls with glass filled nylon, you can get some decent properties from it, much better than hobby sla machines.

Otherwise, it sounds like it's flat? You could laminate sheets cheaply (wet lay - easy composites) and get them water jet cut, followed by some fettling to get the bevelled edges (decent dust mask!). Further still, I think easy composites sell premade sheets. Not sure about 4-5mm as that's properly thick, I imagine you could add / change the geometry /add core to get the bending properties you need. Would need more info on the application.

[daver777]

don't forget machining that stuff creates a dust, which is not a good idea to breathe in.

I have the kit to the cnc stuff and make the sheets however, pm me if you need help.