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Tim Wescott[_6_] Tim Wescott[_6_] is offline
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Default Repair dent in aluminum MacBook laptop?

On Thu, 04 Jun 2015 14:34:34 -0400, Ed Huntress wrote:

On Thu, 4 Jun 2015 12:57:17 -0500, "Terry Coombs"
wrote:

Jim Wilkins wrote:
"rangerssuck" wrote in message
...
On Thursday, June 4, 2015 at 8:06:17 AM UTC-4, John B. wrote:

It is easy to do,
just paint the area with a marker - permanent or white board - and
then heat the area with a torch until the marker goes away.

Interesting - i'd never heard of using a marker as a heat indicator.
Any idea what temperature that "vanishing point" would indicate?

I've always used these:
http://www.tempil.com/products/tempilstik-original/

Supposedly around 800F, which isn't too far below the
(alloy-dependent) melting point. Aluminum melts without glowing red,
so don't heat it much past that vanishing point or you'll reach
another one.

I'd practice on a piece of 6061 sheet first, especially if you don't
have hands-on experience forming metals that work-harden and crack.

-jsw


Chances are that the case was drawn/stamped in a single op , if so
work-hardening shouldn't be a problem .


Macbooks built since 2008 are made of extruded blocks of
"aircraft-quality" aluminum. In the consumer world, at least among
quality manufacturers, that generally means any heat-treatable grade.
I'm told it's 6061, but my source wouldn't be able to tell that from
beverage-can aluminum.

The extruded billet is machined. I don't know how they finish it, but
it's alleged to be "hard-anodized." That sounds funny, because hard
anodizing (which is no harder than regular anodizing, only thicker)
generally is dull and gray. Macbooks look pretty bright.

Anyway, they're apparently not stamped, but rather 3D milled. That
shouldn't influence knocking out a dent, but if the aluminum is any
heat-treatable grade, and hard, it could crack if you don't anodize it
first.

Frankly, doing that, if one isn't comfortable with heat treating, could
be problematic.

One last point: If the OP decides to go for it, and finds a way to
anneal that corner, make sure he finishes knocking out the dent within a
day or so. 6061, if that's what it is, starts to age-harden pretty
quickly.


From the picture it's stamped, not extruded and machined.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com