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World’s First Carbon Fiber 3D Printer Announced

3dprint.com

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Re: World’s First Carbon Fiber 3D Printer Announced

#21

Post by batoure »

grmarcil wrote: post #20
batoure wrote: post #8

Earlier quoted context omitted.

I think that this is more of an 80 20 kind of question. At this level the argument isn't "hey this is as good as carbon fiber" but "hey this is better than regular 3d printing filament"

I agree in part, but I think you're overlooking a big tradeoff here. Printing with plastic filaments gives you a fairly weak piece, but leaves open the door for a lot of post-printing finishes (surface smoothing, using the piece as a positive image to invest, melt out, and cast as metal, etc). You give up a lot of those opportunities printing CF strands, so this printer really does need to be able to produce pretty s…

I'm not overlooking that at all. The point here is that it addresses a different and interesting use case and is ultimately a welcome addition to the market.

Re: World’s First Carbon Fiber 3D Printer Announced

#22

Post by mitchty »

lamby wrote: post #19
return0 wrote: post #3

Please wait while your new bike is being printed.

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

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

Re: World’s First Carbon Fiber 3D Printer Announced

#23

Post by return0 »

mitchty wrote: post #22
lamby wrote: post #19

Earlier quoted context omitted.

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

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

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

Re: World’s First Carbon Fiber 3D Printer Announced

#24

Post by scottdw2 »

kyrra wrote: post #9

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…

That's the whole point.

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

Re: World’s First Carbon Fiber 3D Printer Announced

#26

Post by sbierwagen »

Florin_Andrei wrote: post #15
542458 wrote: post #2

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 carbo…

> 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 fi…

From the product page: http://markforged.com/ (This HN submission is blogspam)

  The incredible strength of carbon fiber comes from the 
  long, continuous strands that carry load down the entire 
  part. This is why space shuttles, rockets, and Formula 1 
  cars are constructed from continuous strand carbon.  And 
  it’s how we print.  Don’t settle for plastic with a dash of 
  chopped carbon fill. Longer is stronger.
  -
  7mm x 3mm x 100mm.  3D Printed beam is packed with tens of 
  thousands of full length, continuous carbon fiber strands
Conventional thermoplastic FDM printing has a lot of design constraints: no overhangs, voids, etc. Looking at this, it seems like it takes those design constraints, and adds some more: the fibre is aligned in the direction of the print head! This is going to take some really tricky modelling work to get it to print what you want, with the direction of strength actually oriented in the direction you want.

And how do you even cure it? Is it just carbon fibre in a thermoplastic matrix?

Re: World’s First Carbon Fiber 3D Printer Announced

#27

Post by Timmmmbob »

Florin_Andrei wrote: post #15
542458 wrote: post #2

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 carbo…

> 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 fi…

> 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.

Re: World’s First Carbon Fiber 3D Printer Announced

#28

Post by marvin »

Timmmmbob wrote: post #27
Florin_Andrei wrote: post #15

Earlier quoted context omitted.

> 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 fi…

> 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 fibr…

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.

Re: World’s First Carbon Fiber 3D Printer Announced

#30

Post by a-priori »

marvin wrote: post #28
Timmmmbob wrote: post #27

Earlier quoted context omitted.

> 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 fibr…

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.

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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