Repair dent in aluminum MacBook laptop?

Post by mike
I have an old MacBook aluminum laptop that got dropped on a corner.
I'd like to beat the dent out of it so the lid will close properly.
It's some kind of drawn aluminum can...I think...
Model number suggests it's not the titanium model.
Here's what it looks like.
http://i.imgur.com/ApOjfl4.jpg
http://i.imgur.com/yRQFVR1.jpg
Hope the image links work.
I can, with considerable difficulty, remove the guts and the
casting around the battery hole.
But there are still some brackets welded to the aluminum
on both sides of the corner.
I can fabricate some wooden forms to recreate the corner.
First question is, "should I try to press it into shape,
or ballistically deform it with a hammer?"
Other suggestions?
It's not worth spending any money to do this.
It's just a learning opportunity.

Why didnt you just take out the screw/bracket so you can see? You will
need a metal anvil then planish by hand, you wont get it perfect but
close, depending on your skillset. C+

John B.

2015-06-04 12:06:12 UTC

You might want to anneal that corner before you try to take the dent
out. I find that often when aluminum is formed that there is some work
hardening and it is useful to soften the aluminum. 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. Don't get
excited and decide that if a little heat is good more might be better,
it isn't, but it isn't rocket science either.

Then I would either press or pound the dent out. Some kind of dolly
and planishing hammer might be a good scheme but a smooth ball peen
will probably work.
--
cheers,

John B.

rangerssuck

2015-06-04 14:47:39 UTC

Post by John B.
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/

Ed Huntress

2015-06-04 14:54:04 UTC

On Thu, 4 Jun 2015 07:47:39 -0700 (PDT), rangerssuck

Post by John B.
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/

I don't know the temperature for markers, but this is a variation on
the method used in aluminum bodywork for most of a century.

If you have to work out a dent, you strip the paint, like you would
with steel bodywork, and then you take your O/A torch and light it
with no oxygen. You then play the sooty flame over the aluminum,
giving it a thin coat of soot.

You then turn on the oxygen and heat the aluminum until the soot just
burns off. This is something typically done with a rosebud torch.

It's not very accurate, but it's good enough to anneal the aluminum
sifficiently to work it with a hammer and dolly -- or a slapper and
dolly, more typically with aluminum.

--
Ed Huntress

Jim Wilkins

2015-06-04 16:54:40 UTC

Post by John B.
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?
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

Terry Coombs

2015-06-04 17:57:17 UTC

Post by John B.
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?
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 .

--
Snag

Ed Huntress

2015-06-04 18:34:34 UTC

Post by John B.
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?
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.

--
Ed Huntress

Tim Wescott

2015-06-04 18:52:44 UTC

Post by Ed Huntress

Post by John B.
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?
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

Ed Huntress

2015-06-04 19:01:27 UTC

This post might be inappropriate. Click to display it.

Lloyd E. Sponenburgh

2015-06-04 19:17:41 UTC

Post by Ed Huntress
t could crack if you don't anodize it

Very likely will crack even if you DO anodize it.

I'd be more prone to tell him to anneal it.

Lloyd

Ed Huntress

2015-06-04 19:33:59 UTC

Post by Lloyd E. Sponenburgh

On Thu, 04 Jun 2015 14:17:41 -0500, "Lloyd E. Sponenburgh"

Post by Ed Huntress
t could crack if you don't anodize it

Very likely will crack even if you DO anodize it.
I'd be more prone to tell him to anneal it.

Aack! I meant anneal, not anodize. Great, now I'm really screwing him
up, I'm sure.

These seemingly simple little things can really get messy. If it's
6061, no matter what he does, he's going to have a range of different
hardnesses across the dent a week or two after he knocks it out. That
shouldn't matter at all in this job, but it will make a big difference
if he anneals it and then lets it sit for a week before he pokes the
dent out.

Here's something for those with a general shop interest, although it
doesn't apply to the OP's question. With 6000 or 2000 Series
aluminums, you can anneal them, and they will never harden. But raise
the temperature a bit to the "solution" stage, and they'll naturally
age harden. 6061 will harden to T3, just sitting there. I think that
2024 is in the same range. And if you anneal with a torch, you're very
likely to hit the solution temperature in some part of the job.

Where hardness changes, you have a weak spot. Again, that should mean
nothing in this case, but it could matter on another project. Heat
treat aluminum with care. It doesn't behave at all like steel.

--
Ed Huntress

Post by Lloyd E. Sponenburgh
Lloyd

Steve W.

2015-06-04 22:58:07 UTC

Post by Ed Huntress

Post by John B.
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?
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 .

6061 is correct. Milled from a single billet because it allows for
mounting points and standoffs to be machined without adding material.
Plus they are heat treated to make them stronger and stiffer.

Post by Ed Huntress
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.

Type 3 anodized, with a decorative second treatment.

Post by Ed Huntress
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.

Anneal yes BUT it will probably still fracture.

Post by Ed Huntress
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.

--
Steve W.

Ed Huntress

2015-06-04 23:21:50 UTC

Post by Ed Huntress

Post by John B.
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?
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 .

6061 is correct. Milled from a single billet because it allows for
mounting points and standoffs to be machined without adding material.
Plus they are heat treated to make them stronger and stiffer.

Hoookay. So, maybe they've gone back and forth on the production
method.

Type 3 anodized, with a decorative second treatment.

Aha. I see that a Type 3 coating on 6061 is 0.003" thick and "dark
gray," which is what I've seen. They must apply a coating that looks
brighter.

Anneal yes BUT it will probably still fracture.

Yeah, I meant anneal. Brain glitch.

Thanks for the clarifications.

--
Ed Huntress

John B.

2015-06-05 01:48:55 UTC

Post by John B.
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?
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 .

Yes and no. But I've found a lot of aluminum "things" bend better
after "annealing" :-)
--
cheers,

John B.

John B.

2015-06-05 01:46:09 UTC

On Thu, 4 Jun 2015 07:47:39 -0700 (PDT), rangerssuck

Post by John B.
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/

No idea, but you can also "smoke" the area with an acetylene torch
with a very rich flame... or even a candle :-)

I suggested the markers because (1) it works and (2) you might not
have an acetylene torch :-)
--
cheers,

John B.

c***@snyder.on.ca

2015-06-05 02:03:03 UTC

Post by Ed Huntress
On Thu, 4 Jun 2015 07:47:39 -0700 (PDT), rangerssuck

Post by John B.
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/

No idea, but you can also "smoke" the area with an acetylene torch
with a very rich flame... or even a candle :-)
I suggested the markers because (1) it works and (2) you might not
have an acetylene torch :-)

In the aircraft world we use soap. When the soap melts and turns
bown(cooked) it's annealed..

c***@snyder.on.ca

2015-06-04 16:35:10 UTC

Post by John B.

You might want to anneal that corner before you try to take the dent
out. I find that often when aluminum is formed that there is some work
hardening and it is useful to soften the aluminum. 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. Don't get
excited and decide that if a little heat is good more might be better,
it isn't, but it isn't rocket science either.
Then I would either press or pound the dent out. Some kind of dolly
and planishing hammer might be a good scheme but a smooth ball peen
will probably work.

It's an APPLE. carve out a negative of the case, with the repaired
corner, out of some strong material. Put half an oz or so of C4 in the
case, clamp the negative mold tightly anround the case and detonate.
That should push the dent out - and since APPLE equipment is so
extra-ordinarily robust, it shouldn't do any harm to the computer ---
(tongue firmly planted in cheek)

Joe Gwinn

2015-06-04 13:18:27 UTC

There is a standard way to fix such problems in hollowware (such as
silver bowls and pitchers) and to make hollowware called "chasing".

Basically, one hammers a blunt tool into the sheet metal, which is
resting on a bed of pitch. No special tooling is used.

In your case, the frame corner would be pushed by hand into warm pitch,
which would then be allowed to cool. Then, working from the inside of
the frame, the corner would be pushed out by hammering a rounded
hardwood dowel into the corner, stretching it back roughly into place.

I learned this in a course on making jewelry. The textbook was
"Metalwork for Craftsmen" by Emil Kronquist, Dover 1972.

Joe Gwinn

e***@whidbey.com

2015-06-04 16:31:49 UTC

I just recently made a similar repair to my iPad. I dropped it and the
corner deformed to the point that the glass broke. Anyway, I took
everything apart to replace the glass and used a small tool I made
from a small flat blade screwdriver to pound the corner back out. I
rounded the end of the screwdriver blade, which was about 3/16" wide,
such that the end is now a section of a thin disc. The radius of this
disc section is slightly less than the radius of the corner. I then
braced the aluminum case with some resilient material and made several
taps on the handle end of the screwdriver while the tool was engaged
with the work. I thought, before opening it up, that the iPad case
was drawn or stamped aluminum but it is actually machined, there are
cutter marks visible in many places and even some chatter marks. You
want the aluminum to move every time you hit the screwdriver, too
light a hit will start to harden the metal and it may crack. I used a
small ball pein hammer that Starret sells which has a magnifying lens
in the hammer head, it was the perfect weight. But any small hammer
will do. The trick is to always move the metal with each hit and to
complete the job with as few hits as possible.
Eric

Lloyd E. Sponenburgh

2015-06-04 16:33:40 UTC

There is a mantra for repairing old MacBooks that reads a bit like the
classic recipe for cooking Tofu:

1) Throw the Tofu in the garbage
2) Buy some meat.

Much the same treatment works well for MacBooks.

Lloyd

Larry Jaques

2015-06-05 04:56:36 UTC

Post by Lloyd E. Sponenburgh

On Thu, 04 Jun 2015 11:33:40 -0500, "Lloyd E. Sponenburgh"

There is a mantra for repairing old MacBooks that reads a bit like the
1) Throw the Tofu in the garbage
2) Buy some meat.
Much the same treatment works well for MacBooks.

+1

--
It takes as much energy to wish as to plan.
--Eleanor Roosevelt

Michael A. Terrell

2015-06-05 13:51:03 UTC

Post by Lloyd E. Sponenburgh

Post by Larry Jaques
On Thu, 04 Jun 2015 11:33:40 -0500, "Lloyd E. Sponenburgh"

There is a mantra for repairing old MacBooks that reads a bit like the
1) Throw the Tofu in the garbage
2) Buy some meat.
Much the same treatment works well for MacBooks.

I like Apple computers. I use them for doorstops. They work great,
after you fill them with concrete. :)

DoN. Nichols

2015-06-05 03:01:34 UTC