Leliel Carbon

[Josh | NFC]

Normally I like to have a good amount of content to share when making a post. It is only polite, afterall.

This year I would like to enter the Coolermaster Case Mod World Series. Registration deadline is looming, so I need to start the required worklog asap. I hope our SFF mods will forgive me and I will try to get something posted here as soon as I can.

Leliel CARBON
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I name all my mods after angels in Hebrew mythology. Leliel is the choice and inspiration for my 2017 build. Each year I incorporate a new material to my sculpture. This year is is carbon fiber. I have avoided this material for many years because I have wanted to use a military weave and the difficulty of working with this material (and toxicity) has put me off.

Auriel's design needs to be further explored. I was quite happy with how Auriel evolved from Puriel, with little sacrifice save for losing drive bays, and I hope to make some further refinements to Leliel along the same slimming vein, making her a aptly named sister to Auriel. As this is the small form factor forum my goal, as always, will be to make good use of space.

Finally, as with all my builds, I have one last requirement--uniqueness. Execution, quality, craftsmanship are important, but my primary focus as with all my builds is it must do something new and stand apart.

 

[|||]

Good luck with this!

This year is is carbon fiber. I have avoided this material for many years because I have wanted to use a military weave and the difficulty of working with this material (and toxicity) has put me off.

I've worked on defense projects using composite construction and have never heard of a "military weave." Could you elaborate?

I'm sure @craigbru would be interested in this project.

 

[Phuncz]

Oh this is going to be good ! Can't wait to see what you'll come up with ! CF structure, oh my !

 

[GentlemanShark]

For the contest does the mod have to be done before the 31st?

 

[craigbru]

Ooh, carbon fiber... Nice. I wanted to enter the contest, but knew there would be no way to get a project done in time. IIRC it would have to be done my May 1st?

I'd be happy to help with any CF related questions if I can Josh.

 

[Josh | NFC]

Good luck with this!



I've worked on defense projects using composite construction and have never heard of a "military weave." Could you elaborate?

I'm sure @craigbru would be interested in this project.

I'm not super technical, but I am referring to PITCH based weaves encased in ceramic matrices (P-CMCs). Again, not an expert, but being into cameras and friend who are into cars, there is a big difference in the Rayon and Pitch based weaves, and still a difference in PAN--and of course the binding/encapsulating agent makes a tremendous difference.

As an example, I was used to the fiberglass feeling rayon stuff when working with some friends on car projects. A year or so ago my friends who have a defense contract working on a particular part for a water landing craft let me take some ruined scraps home. This stuff is only 3mm thick and is harder than anything I have seen in my life. It sounds like ceramic plates, because, well, it basically is. They have to pre-drill this stuff with the drill press Thor uses before they can use their huge waterjet to cut it because it is so hard the water sprays everywhere and can't get a clean start.

Naturally, I was intrigued...and I don't want to settle for Chinese Rayon-based panels now. Of course when I see the materials cost I might be inclined to change my mind.

 

[craigbru]

Yeah, the cost is always a little hard to swallow. Especially if you want to head in a little more exotic direction. My experience is mostly with more traditional weaves and resin layup. There's a certain science to it, but it's really not as complicated as some make it out to be.

So, you're looking at a panel based design?

 

[Josh | NFC]

Yeah, the cost is always a little hard to swallow. Especially if you want to head in a little more exotic direction. My experience is mostly with more traditional weaves and resin layup. There's a certain science to it, but it's really not as complicated as some make it out to be.

So, you're looking at a panel based design?

The plan right now is to do panels, and if time is looking good there are a few parts I want to form. Obviously this wont be made out of the same stuff as the panels. Any direction you have regarding that would be most appreciated. As time is short, those parts might end up being made out of something I have experience forming.

 

[|||]

Ceramic-matrix composite (CMC) require kilns to get up to pyrolyzing temperatures and many repeated steps to get the material fully infiltrated to form the ceramic matrix. For example, the $8-10K ceramic brake packages that sports cars use are a silicon carbide reinforced carbon fiber. Those are formed by creating the disk shape with dry carbon fiber, putting them in high temperature molds, and firing them in a kiln with a silicon-rich atmosphere. Carbon/carbon racing brake disks are made the same way, except with a carbon-rich atmosphere. There is another way to create SiC/C with a wet-lay using polysiloxane, as these guys do. Again, many steps of reapplying the polysiloxane to infiltrate the carbon to form the matrix at very high temperatures.

As for pitch and polyacrylonitrile (PAN), yes, pitch is higher performing, but it is also a bit more expensive. There is also a difference between carbon fiber and graphite fiber...graphite fiber goes through an additional high temperature graphitization process and results in superior properties, but costs more due to the additional processing.

I'm not trying to discourage this at all...just letting you know what it takes and can be $$$$$$.

 

[Kmpkt]

Every time I read Leliel, I can't help but think it sounds like "lol". : (

 

[confusis]

lolol!

The ideas sound interesting. Gives me motivation to consider a scratchbuild.

 

[Josh | NFC]

Ceramic-matrix composite (CMC) require kilns to get up to pyrolyzing temperatures and many repeated steps to get the material fully infiltrated to form the ceramic matrix. For example, the $8-10K ceramic brake packages that sports cars use are a silicon carbide reinforced carbon fiber. Those are formed by creating the disk shape with dry carbon fiber, putting them in high temperature molds, and firing them in a kiln with a silicon-rich atmosphere. Carbon/carbon racing brake disks are made the same way, except with a carbon-rich atmosphere. There is another way to create SiC/C with a wet-lay using polysiloxane, as these guys do. Again, many steps of reapplying the polysiloxane to infiltrate the carbon to form the matrix at very high temperatures.

As for pitch and polyacrylonitrile (PAN), yes, pitch is higher performing, but it is also a bit more expensive. There is also a difference between carbon fiber and graphite fiber...graphite fiber goes through an additional high temperature graphitization process and results in superior properties, but costs more due to the additional processing.

I'm not trying to discourage this at all...just letting you know what it takes and can be $$$$$$.

Thanks for all that info!

Just to be clear, I am going to be using small sheets that can be cut with the drill 'n jet process that my friends are already employing professionally. I am not planning on making my own ceramic plates...however awesome that would be...

 

[|||]

Yeah, if you have access to scrap, that could be sweet. All the better if they can cut them to the size you need with the features on them, as a ceramic material like silicon carbide is nearly as hard as diamond. Perhaps you can look at bonding panels and form a semi-unitary structure, which would probably be as light and compact as you could get.

 

[MarcParis]

@Josh | NFC I wish you good luck for this competition!

 

[Epinephrine]

I'm sorry if this sounds blasphemous, but is Auriel meant as case + monitor stand? Cause that would be awesome.

 

[LjSpike]

Just a question, but you mention the toxicity of military weave, now I'm not particularly familiar with this specific material, but if it's a ceramic, why would it be toxic? Just changing the structure of a material doesn't alter it's toxicity, the compounds which make it up do that.

I just bring it up because it reminded me of an old video with a similar mention but no reason to bring up such a mention...

 

[jeshikat]

Just changing the structure of a material doesn't alter it's toxicity

That's not quite true, carbon in most forms isn't harmful, but carbon nanotubes have a structure similar to asbestos so it has the potential to cause the same kind of lung problems if inhaled.

 

[LjSpike]

That's not quite true, carbon in most forms isn't harmful, but carbon nanotubes have a structure similar to asbestos so it has the potential to cause the same kind of lung problems if inhaled.

Eh, that is a point which I can't completely refute as it falls down to the exact definition of toxicity your using. Also, as far as I know it's just speculation that they could have the same dangers as asbestos.

Crucially toxicity I would define as the capacity to harm an organism via toxins / poisonous agents, giving it the "Skull & Crossbones" GHS.
Things which are severely harmful in the way you describe I would give the following pictogram:

Wikipedia has an alright page of GHS pictograms here: https://en.wikipedia.org/wiki/GHS_hazard_pictograms