Aluminium and laptops

Okay... Most people will agree that the Macbook Pro, as well as the Macbook Air feel very solidly built and that aluminium for electronic devices makes them feel very high quality, but is it really that good?
I've talked about this quite a lot on /g/ so I thought I should write a blog post on it, so that I don't have to repeat myself so much.

So aluminium, a very nice metal used in a wide variety of things from soda cans to aircrafts, and lots of laptops these days. It's very light and quite durable but there are a few things I dislike about it.


1) Thermal conductivity
Aluminium is a great thermal conductor. I won't go into the heavy math or details, but trust me when I say it's great at conducting heat. It's the most common material used for heatsinks for CPUs and GPUs because of its light weight and its great heat conductivity capabilities. Making a laptop out of it, is not a great idea. Especially not if the laptop does not have proper ventilation and airflow, which the Macs does not have. The body being made out of aluminum, and the bad airflow the Macs has leads to them often becoming very very hot. Apple has even written:
>Do not place your MacBook Pro on your lap or other body surface for extended periods of time. Prolonged body contact can cause discomfort and potentially a burn. The bottom of the MacBook Pro case functions as a cooling surface that transfers heat from inside the computer to the cooler air outside.
On their safety information page.

2) Dents
So the case is made out of aluminum, and most of the heat generated by the components is transferred into the aluminium case. Metal gets soft when heated up, and a heated up aluminum case becomes soft as well. This might not be that big of a problem, but if you run a CPU and/or GPU intense program, and drop your Mac (or hits it) then it will quite easily be dented. Plastic, at least high quality plastic, absorbs the shock a lot better. The case on the ThinkPad series from Lenovo has a high quality carbon fibre case which is much more durable and shock resistant than the aluminium used for the Macbook Pro and Air.

3) Finger Prints
Ever wondered why lots of Macbooks looks dirty? Well that's quite easily explained. It's because they are made out of anodized aluminum. We humans have lots of oils and acids on our fingers and it is perfectly natural. What happens when these oils and acids comes in contact with anodized aluminum? The oils and acids literally etches into the aluminum surface and you can not clean it. I have this problem with my iPod Touch. The back is very very dirty, and this dirt is permanently stuck on the back.

Final thought
While aluminum is durable and light, it does have some problems which does not exist with high quality plastic or carbon fiber. If I were to pick between low quality plastic and aluminum then I'd definitely pick the aluminum, but if I were to pick between high quality plastic and/or carbon fiber or aluminum then I'd pick the high quality plastic (or the carbon fiber).