Newbie: Make a CF intake

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#1

Hello,

Have been reading this great forum and wanted some advice for a first project. I wanted to replicate an intake tube I have on my car but in CF. Its basically just 3" in diameter with a small 30 degree bend in it. My question is, what is the best way to approach this?

Is there a way to make a male mold, that I can wrap the CF around, but then to get the male mold out? Like my idea is to make a female mold out of my current intake, make a male out of that. Then wrap it in carbon fibre and find some way to get it out afterwards. Can I pour some plaster then just crack it out after?

And how many layers of CF will I need to use? Does CF have better resistence to heat then say the typical powder coated aluminum?

Thanks!

#2

no need to make the male mold after the female. research bladder molding techniques.

#3

Thank you for the tip. I went searching on google and found exactly what you suggested.

http://www.hexcelcomposites.com/Markets/Products/Thermoplastics/Process/Bladder.htm

Where do I find a bladder that is made for that job? Also, do I really need that much psi for this job? 150-200psi sounds like a lot to me. Mine tops out at 90psi.

Thanks!

#4

Most of the time you would have to make your own bladder. Look up uncured silicon sheets. If you cant get them for whatever reason I can get them for you. It iss not cheap though. Here are some places to start out with:
Airtech International - makes vacuum bag and resuable vacuum bag materials (ask them for uncured silicon sheets)
Bondline - makes reusable vaccum bags
Torr Tech - same as the first two

Evan

#5

There are a few soluble mandrel materials that may be of some use to you also. I’ve researched doing the exact same thing and realized it would be a giant expensive pain in the ass for the small amount of weight savings over the aluminum intake tubing you’re trying to replace. I’ve almost settled on using carbon sleeve and bagging right over the aluminum, leaving it in place permanently. You’d get the slightly lower thermal transfer of the carbon, and it would still look nice. If you’re still determined, or want to do a funny shape (J’s Racing intake for Hondas, for example) you could make two halves of the shape, join and trim them, and figure out some way to reinforce the seam from the inside. The soluable mandrel materials are kinda pricey, but sound like they could really make some cool stuff. They pack into a form, can take bagging pressure and heat, and then can be dissolved away after cure. One of the brands is water soluable.

I’ve also toyed with the idea of using a two part foam, pouring it into a mold, which should give it an OK surface finish, and then dissolving it out chemically after layup.

I’ve never tried any of these methods, these are just things I’ve thought about and researched… Can anyone else shed some light on this?