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Comment by sandGorgon | Hacker News Reader

question - why is everyone making alumninium unibody notebooks ? Is carbon fiber not lighter and (arguably) just as strong. Is it just the design aesthetic that everyone is trying to reach out for or is there something else.

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Aluminum conducts heat really well.

Because CF is still ridiculously expensive. It's cheaper now to make than before and you might see it around more often, but it's still an exotic material. Otherwise, we would see it everywhere.

sony makes laptops using carbon fiber - http://store.sony.com/webapp/wcs/stores/servlet/CategoryDisp...

same ballpark pricing ~2000 USD. Is unibody aluminium that commonplace a manufacturing process that it is much more feasible than carbon fiber ?

Oh nice. That looks like a pretty slick laptop. I like the lightpeak integration w/ external video card & BluRay support.

I always thought that carbon fiber weaving was not widespread and thus that was one factor in the high cost of carbon fiber. For example when Lexus was building their LFA car they also built their own 3D CF loom. http://www.youtube.com/watch?v=ry9uiP2I6kQ

Typically though you don't custom-weave CF into the product shape; you buy CF cloth and lay it into a mold. I think, though, that a lot of composite layup is still done by hand since it is not as easy to automate as a lot of metalworking processes are.

If I had to guess, I'd say that it's easier to cast and mill the aluminum unibody than it is to mold the carbon fiber.

Probably cheaper, as well.

hmm.. I honestly never thought that was the issue, given how popular graphite tennis racquets are.

What about fiberglass then ? I even saw a show on TV, where they remade a car chassis by handfilling fiberglass filaments and the resulting could withstand sledgehammer blows.

does fiberglass/carbon-fiber affect laptop cooling ?

The processes for Fiberglass and carbon fiber are nearly identical (both use mats of the material and resins that have to be formed/cooked (in the case of carbon fiber)).

I would imagine carbon fiber wouldn't conduct heat quite as well as aluminum, but I don't have any data on that.

Fiberglass is a quite good insulator. So, if carbon fiber behaves similarly to fiberglass, it would be very poor for cooling, relative to aluminum.

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