Computer Case

General Composites Discussions Composites Talk
#1

I know its over the top, but I have plans to make a Carbon Fiber PC case.

I do apologize if my description is foggy or isn’t as readily understandable, I’m more then happy to explain or clarify something.

The case design is 24’ length x 23’ height x 9’ width, the ‘frame’ would be one solid piece of CF, laid up along the length/height of a mold.

the CF cloth I’m using is: 2x2 Twill 12k 19.7oz, 0/90 Biaxial 12k 8oz, and 2x2 Twill 3K 5.7 oz. (I will be using a wet layup w/ vacuum bagging)

The 3k 5.7 oz is going to be used as the outermost layer.

My dilemma is:

-What type of mold release to use
-what kind of resin (I’m thinking epoxy)
-do i need more then one type of mold release
-is there anything else I might need to know/might of missed?

Any and all feedback would be -greatly- appreciated.

#2

Mold release is a personal choice. Semi-perms are easy to use. Wax is common, and PVA is as well, but that is really hard to use sometimes.
Epoxy, or a VER would work. Many carbon fabrics don’t like VER, so an epoxy would be my #1 choice.
You don’t need more than one. I do know people that wax, THEN semi-perm, but that might be over kill. Depends on your mold too…a new mold might need a wax for sealing it.

Are you building the box via a mold, or gluing flat panels together to make a box? If the latter, you need to find a good adhesive to join the sides, or even use brackets to bolt it all together.

#3

I’ve always waxed new molds 3-4 times just to ensure that my part doesn’t stick to a new mold. The extra time spent applying mold release is well worth a mold that survives the layup and a part that comes out easily. I follow up the wax with PVA, and for small molds, I use a small piece of T-shirt material (high-tech, I know) to apply the PVA and that seems to work pretty good. I’ve used PTM&W tooling resins for my tools and epoxy resins from the same company for my layups as well as West Systems. Unlike polyester resin, epoxy is an actual adhesive, so it really brings out the high strength qualities of carbon. Good luck! Try to post some pictures of your progress if you can.

#4

If you want the semi-permanent release to transfer to the part then apply it over wax. This can be very problematic. There is not a semi-permanent release manufacturer the recommends applying it over wax. In fact, all of them want you to thoroughly remove any wax before applying their semi-permanent system. You should also follow their recommendation to use their sealer before applying the release system. The sealer will increase the longevity of the release, improve the release, and block some of the chemical reactivity.

Using just wax can work with SOME combinations. Just wax with epoxies can be very problematic. If fact, some epoxies will stick firmly to even semi-permanents. The only option with these is to use wax and PVA. It’s important to test the release surface-release-layup resin combination prior to committing to it’s use.

#5

Hi it’s easy to over complicate moldings, if you are making a one off case I think you would find it more cost effective and much quicker to make a mdf or ply box to your dimensions and cover it all with a composite flash tape (think special sellotape) or sticky back ptfe type release film. I often use standard parcel tape with just a light wax over. You will need to sand and clear coat to get a A class finish but the end product will be just as good and you would have saved yourself many hours and a plenty of cash going the standard plug and mould route.

For example if you already have a case you could just cover it a 2 inch parcel tape run a couple of wax’s over it. Hand consolidate so no vacuuming and you will still get a very god product that should be stiffer than vacuuming. The drawback is you will need to add a fill coat and sand and clear to get the finish. But bear in mind having a mould and vacuuming or infusing is no guarantee you will not end up doing this anyhow.

#6

I recently finished a Carbon Fiber computer case myself. It is logged over at Bit-Tech.net in their project log forums under the name SSR-X. This was a scratch build, though, I am thinking about taking a existing computer case and making it into carbon fiber.

#7

Very interested to see how this works out. I want to make something similar where I can mount the guts of a PC to a wall mounted, skeletonized carbon frame with an acrylic cover over it. Run LED backlit liquid cooling and make it all TRON-ish :slight_smile: Absolute cool factor for the garage!

Be interested to see your ideas if you care to discuss in how you plan to mount the components. Bonded stainless threaded inserts was the way I was planning to go.

#8

For the mainboard you can easily mount the brass standoffs with a dab of glue in predrilled holes. On my PCs the videocard etc were not supported by any means, but you can design a strip of material (carbon, alu, steel) in the right spot if needed.

The rest of the stuff is easy to mount, and remember: less is more!