
World’s First Carbon Fiber 3D Printer Announced - willwill100
http://3dprint.com/worlds-first-carbon-fiber-3d-printer-announced-the-mark-one
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542458
Count me as skeptical. The strength of high-quality carbon fibre comes from
having many pieces of fibre woven together over the surface omnidirectionally
(Okay, I'm mostly wrong here - see below). This machine seems to simply lay it
down in a (more or less) continuous strand, which means that the fibres will
be cohesive rather than woven together. You can do this without a special
printer - all you need is some carbon fibre/pla filament [1]. My bet would be
that polycarbonate 3d printed parts [2] will be stronger that these pseudo
carbon-fibre parts in most situations.

For a pretty freaking cool view of how high-quality carbon fibre parts are
made check out this youtube link:
[https://www.youtube.com/watch?v=l4DLr8qHliI](https://www.youtube.com/watch?v=l4DLr8qHliI)

[1]: [https://www.kickstarter.com/projects/1375236253/proto-
pasta-...](https://www.kickstarter.com/projects/1375236253/proto-pasta-
gourmet-food-for-your-3d-printer)

[2]: [http://www.makerfarm.com/index.php/2-2lb-1kg-1-75mm-clear-
po...](http://www.makerfarm.com/index.php/2-2lb-1kg-1-75mm-clear-
polycarbonate-filament.html)

~~~
Florin_Andrei
> _The strength of high-quality carbon fibre comes from having many pieces of
> fibre woven together over the surface omnidirectionally._

No, not at all.

The strength of CFRP (carbon fiber reinforced polymer) comes from having very
long strands of carbon fiber, ideally as long as the whole piece, held
together by some polymer matrix such as epoxy resin. It also comes from having
a very high fiber-to-epoxy ratio in the final product, which is usually
achieved by squeezing out all the extra epoxy using vacuum while curing.

The length of the fibers, and the minimal amount of epoxy, is what makes CF
strong. Short fibers, and having too much epoxy matrix, weakens the composite.

There is a kind of extruded CF where short CF fibers are mixed with epoxy
matrix and extruded in the desired shape. This is strong compared to ordinary
plastic, but not as strong as long-fiber CF.

What you're describing is woven CF, and it's not the strongest there is. The
strongest CF pieces are made of unidirectional CF, where all fibers are
oriented in the direction of the main effort. E.g., CF tubes are strongest
when they are made of unidirectional CF, with fibers as long as the whole
tube.

Woven CF is a good compromise in that it's reasonably strong in several
directions in the plane of the CF cloth. Also, for CF tubes, an outer layer of
woven CF gives it a bit more resistance to splintering.

Another way to achieve multi-directional strength is by laying unidirectional
cloth alternatively in different directions. The piece will gain strength from
each unidirectional layer in a specific direction.

Most people recognize the classic "CF look" only when the top layer is woven.
Unidirectional CF cloth has a different look. This is why many CF items are
made of unidirectional cloth, with a single woven layer on top.

If this CF 3D printer can lay long-fiber CF, and can achieve a very high
fiber-to-epoxy ratio in the final product, then chances are the pieces
produced this way will be strong.

~~~
Timmmmbob
> The strongest CF pieces are made of unidirectional CF, where all fibers are
> oriented in the direction of the main effort.

You're confusing issues even further! To anyone who wants to actually
understand this:

Carbon fibre doesn't have a single "strength" value since it is virtually
always anisotropic - its strength varies massively depending on which
direction you stress it in.

GP is correct in that the carbon fibre weave with the best _minimum_ strength
is the 3D woven stuff which is very fancy and difficult to make, and not what
this printer makes.

The most common carbon fibre is 2D woven cloth which is laminated together
like plywood. It is strong in the directions of the fibres but can very easily
delaminate (the layers become unstuck). It's a pretty big problem for things
like the Boeing Dreamliner because the delaminations can be under the surface
and impossible to see.

CFRP tubes are often made with the fibres all running along the axis of the
tube, but it is then extremely weak in the circumferential direction and will
tend to split like bamboo.

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marvin
Delaminated Dreamliner sounds like a maintenance person's worst nightmare.
Wouldn't you have to replace the entire part? Where "part" is wing, rudder or
fuselage.

~~~
a-priori
Replacing a defective part is no big deal, just incorporate an inspection of
the part into a regular maintenance window every X cycles (a 'cycle' is
usually one flight) and model its cost as an amortized per-cycle cost based on
its mean time to failure.

The problem is when it's difficult to know whether a part is defective.
Something like subsurface delamination might cause visible bubbling or
warping, but if it's deep enough then it may only be apparent on an ultrasound
or X-ray scan. That sort of scan might be more expensive than just replacing
the part regularly, and shipping it off to a factory to be inspected and
refurbished.

 _That_ is a maintenance technician's worst nightmare: an expensive and bulky
part that fails in invisible ways, requiring either regular replacement or
time-consuming inspection with expensive equipment.

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kyrra
The allure of carbon fiber in industry has to do with the properties of the
material that can be produced. Home made carbon fiber won't be all that great
of a material compared to what people see out in the world (on race cars,
planes, etc...). Production lines for producing commercial carbon fiber is
super expensive ($100 million+). Zoltek has a basic rundown of the process
[0].

[0] [http://www.zoltek.com/carbonfiber/how-is-it-
made/](http://www.zoltek.com/carbonfiber/how-is-it-made/)

~~~
scottdw2
That's the whole point.

It's disruptive technology: not as good, way more accessible.

~~~
fudged71
Yes exactly
[http://www.bhorowitz.com/can_do_vs_cant_do_cultures](http://www.bhorowitz.com/can_do_vs_cant_do_cultures)

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lowglow
I was thinking about 3D printed supercars, (or cars for that matter) because
why not. I have a friend that works for Buell that informed me the industry
has been 3D printing porototypes for a while now. Rapid prototyping has been
something driving this field. He sent me this link:

[https://localmotors.com/press/releases/vehicle-design-
innova...](https://localmotors.com/press/releases/vehicle-design-innovator-
local-motors-signs-crada-with-ornl-to-enable-the-rapid-design-and-
manufacturing-of-vehicles-through-direct-digital-
manufacturing/?utm_source=Local%20Motors%20Community%20Newsletter&utm_campaign=0f58a4105f-Local_Mototrs_Community_Newsletter%3A%20June%2012&utm_medium=email&utm_term=0_4c67861f15-0f58a4105f-294349853)

I've also been giving some thought in starting the worlds first 3D printed
furniture store.

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return0
Please wait while your new bike is being printed.

~~~
lamby
You jest, but I'd be rather intrigued by aftermarket carbon farings for wheels
or to hide brakes from the wind.

~~~
mitchty
There is a lot of cool things you could do with something that prints out 20%
stronger than aluminum parts.

~~~
return0
Is it truly so? how does this process compare to carbon part manufacturing? (i
understand it involves some press/heating).

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adamwong246
I'm holding out for 3d printed graphene.

~~~
moocowduckquack
get a lightscribe drive and some graphite oxide

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adamwong246
I hypothesize that that technique will not work. Graphene molecules are flat,
only 1 atom thick. So while they are strong in 2 dimensions, once you start
stacking graphene vertically, it's just like a stack of paper. The layers
won't be nearly as strongly bonded vertically as they would be along the plane
of graphene. I think you would end up with a product the cleaves easily along
the layers of graphene. I'm pretty sure you going to need a 3 dimensional
arrangement of atoms.

~~~
moocowduckquack
I suspect it might if you doped the graphite oxide with something to muck up
the sheets a little and allow vertical bonds, perhaps a bit of boron.

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buro9
This is the link you're looking for:

[http://markforged.com/](http://markforged.com/)

Product site, video, tech specs, pre-order, etc.

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Glyptodon
With all the questions about epoxy content/ratio, I wonder if it might be
possible to take a page from the metal clay playbook and use a binder that
evaporates as it cures. Or maybe use one that's foam-like or frothy.

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jaydub
Are there health risks associated with extruding carbon fibers? I was under
the impression that working with carbon fiber can be potentially harmful to
your health.

~~~
morcheeba
There are two types of risks:

\- epoxy sensitivity. Work with it too long (years) and you can become
allergic. I can't tell if this system uses epoxy as a binder; it doesn't seem
to because it would be messy.

\- inhaling carbon fiber dust. This dust is made when you cut it, not when you
lay it out. A 3d printer should put it in the right shape, so less cutting
would be required. You'll want to avoid breathing it in, but it's not
cancerous like asbestos:
[http://annhyg.oxfordjournals.org/content/38/inhaled_particle...](http://annhyg.oxfordjournals.org/content/38/inhaled_particles_VII/769.abstract)

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beedogs
apropos of nothing, that floating social media bar in the middle of the page
on this site is _infuriating_.

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abjorn
You had me at carbon fiber.

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lhgaghl
It looks like a mac.

