Hacker News new | ask | show | jobs
by xxs 1758 days ago
>Also, stronger meaning what?

Usually tensile strength. For example: Tensile strength: even a commodity PA6-GF30 (most half-decent tools are made of) is ~110MPa [according to ISO 527], cast Aluminum - would be ~150MPa (22K psi for the imperial folks) depending on the alloy.

Of course, most laptops would be using an ABS blend, which is the hallmark low-quality tools.

>Dents

That would depend on the top finish, not so much of the material itself.

1 comments

> >Dents

> That would depend on the top finish, not so much of the material itself.

Would it? If I dropped an aluminium bodied laptop like a Macbook or HP Envy, I'd expect it might scuff and slightly dent at the point of impact. If I dropped the cheapest plastic bodied thing from Currys/Walmart/whatever, I'd expect it might scuff and crack the plastic between screws or something.

What top finish would you apply to a cheap plastic laptop to make it 'ding' like aluminium instead of crack in a drop test?

I would not consider cracks "dents". I already mentioned the cheap 'ABS' plastic, they would crack (also it's not UV stable). You can look up PA6-GF30 (nylon, 30% glass fiber reinforced) tools and they survive ~2m (6 feet) drop tests. Laptops won't do that as their screens would crash. Here: a popular video[0] of some massive abuse of a multimeter.

Again, a good plastic with glass or carbon fiber reinforcement would have similar properties to al-mg body, yet feel cheap as most people consider all plastics quite the same. For example: polycarbonate, 30% carbon fiber would have tensile strength of 150MPa (which the same to cast aluminum)

[0]: https://www.youtube.com/watch?v=qlA7-fh5nDQ

No, neither would I. I was agreeing with the commenter you replied to, that I'd expect a plastic laptop to crack, and a metal one to dent. If it has to be damaged, I'd prefer the dent.

You said above that that was more to do with 'top finish' than 'material'; that's what I was responding to - how would you finish crackable plastic material to make it dent like aluminium/alloy instead.

Plasti-dip.