Cannot remove caps from motherboard

[Anonymous]

I'm trying to repair my MSI motherboard by replacing the caps near the
regulators since they are bulging and are most likely defective.
However, even at the highest setting of my soldering iron (480 degrees
Celcius) I'm unable to liquify the solder. I don't know what kind of
solder they're using for motherboards but it's obviously not the kind
you can easily manipulate with common DIY tools.

Anyone have a trick for solving this problem?

[Michael A. Terrell]

What tools are you using? A vacuum desoldering iron is the proper
tools. Solder wick is a poor second choice.

Remove what you can, then refill the hole with 63/37 solder which has
a lower melting point. The ROHS crap solder takes a lot more heat to
melt. Clean off the excess flux, then use the vacuum tool again. The
flux will destroy the hollow tip in a hurry.

[Jamie]

feed low temp solder into the junction, it'll soften and mix with it.

or, could it be possible your iron is not properly functioning?

also, by using a blunt tip like a spade tip, it makes the job easier
to heat the area. With small tips you don't have a lot of heat retention.

Jamie

[Tom Biasi]

Keep in mind they are multilayer boards.
Removing parts can be tricky or even damage the intermediate layers.
Dell had a problem with caps a few years back and replacement turned out
to be not nice.

Tom

[k...@att.bizzzzzzzzzzzz]

On Sun, 23 Sep 2012 19:37:35 +0000 (UTC), Anonymous
<nob...@remailer.paranoici.org> wrote:

>I'm trying to repair my MSI motherboard by replacing the caps near the
>regulators since they are bulging and are most likely defective.
>However, even at the highest setting of my soldering iron (480 degrees
>Celcius) I'm unable to liquify the solder. I don't know what kind of
>solder they're using for motherboards but it's obviously not the kind
>you can easily manipulate with common DIY tools.

If it were really 480C, you'd have destroyed the board. Even RoHS solder
melts before 350C. Your iron probably doesn't put out enough heat (wattage
too low) or is defective. These caps are tied directly to internal planes so
it can take a *lot* of heat.

>Anyone have a trick for solving this problem?

As Jamie suggested, you can try melting in some 63/37 solder to lower the
melting point of the solder that's already there. You gotta get the solder
melted before any other techniques will help, though.

[Phil Allison]

"Anonymous"

** Wiggle the caps until they break away from the PCB leaving only the stubs
of the leads in the PCB.

Then you can heat the stubs directly and remove them.

OR, just solder the new caps to them, keeping the leads short.



.... Phil

[Rich Webb]

On Sun, 23 Sep 2012 19:37:35 +0000 (UTC), Anonymous
<nob...@remailer.paranoici.org> wrote:

Might try lowering the melting point with some of ChipQuik. It is
marketed as an aid for surface-mount removal but I'd guess that the
lower melting point might be helpful here as well. Fairly inexpensive,
so it's a handy tool in your kit, regardless. http://www.chipquik.com/

Note: yes, it's kind of a hokey website but the stuff really does work.

--
Rich Webb Norfolk, VA

[fungus]

On Sunday, September 23, 2012 9:38:23 PM UTC+2, Anonymous wrote:
>
> Anyone have a trick for solving this problem?

Get a big pair of pliers and pull very hard!

With a bit of luck you'll leave the legs behind
and you can solder the new cap onto them.

Failing that, add some more solder. This gives
a better thermal contact with the soldering iron.

[Michael A. Terrell]

fungus wrote:
>
> On Sunday, September 23, 2012 9:38:23 PM UTC+2, Anonymous wrote:
> >
> > Anyone have a trick for solving this problem?
>
> Get a big pair of pliers and pull very hard!
>
> With a bit of luck you'll leave the legs behind
> and you can solder the new cap onto them.

Or you'll damage the PTH and destroy the board.

> Failing that, add some more solder. This gives
> a better thermal contact with the soldering iron.

Big deal. You need to lower the melting point by using a solder with
a higher lead content.

[Anna Joshi]

The Do's & Don'ts of an Engineering student.

http://www.youtube.com/watch?v=F-MweIUKAig&list=UUmhLtTCHD3S6Asrfi2zSJ2A&index=5&feature=plpp_video


Subscribe for more footage.

[fungus]

On Monday, September 24, 2012 12:17:49 PM UTC+2, Michael Terrell wrote:
>
> Or you'll damage the PTH and destroy the board.
>

Whoosh.

[Jim Thompson]

I tend toward braid first to "sop" up enough that then the "sucker"
can clear the via.

(One does assume that the OP cut the cap off the leads first ;-)

...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

[Cydrome Leader]

sadly I agree with this.

even with a real iron, it's a serious PITA to remove those things.

[et...@whidbey.com]

On Sun, 23 Sep 2012 19:37:35 +0000 (UTC), Anonymous
<nob...@remailer.paranoici.org> wrote:

I just had to do this, removing a component that was soldered with the
higher melting temp solder. I loaded up the iron tip with low melting
temp solder, applied the iron tip to the soldered lead, waited for the
solder to flow, sucked it off with a solder sucker, and repeated a few
times. I was careful to avoid overheating the board. It was a pain in
the ass because it took so much time, but it did work.
Eric

[Michael A. Terrell]

Whoosh indeed. I worked where circuit boards were manufactured, and
you're a fool. Pulling on a through hole component with pliers can rip
the plating out of the hole. I've scrapped computer boards that fools
like you fucked up. They managed to pull some 28 pin ICs off
motherboards, along with over 20 pieces of the plating, then tried to
bend the leads over to make contact. All connections to the inner layers
were gone, and I wasn't about to run over 100 pieces of 32 AWG wire to
patch them up.

[Michael A. Terrell]

Jim Thompson wrote:
>
> On Mon, 24 Sep 2012 06:17:39 -0400, "Michael A. Terrell"
> <mike.t...@earthlink.net> wrote:
>
> >
> >fungus wrote:
> >>
> >> On Sunday, September 23, 2012 9:38:23 PM UTC+2, Anonymous wrote:
> >> >
> >> > Anyone have a trick for solving this problem?
> >>
> >> Get a big pair of pliers and pull very hard!
> >>
> >> With a bit of luck you'll leave the legs behind
> >> and you can solder the new cap onto them.
> >
> >
> > Or you'll damage the PTH and destroy the board.
> >
> >
> >> Failing that, add some more solder. This gives
> >> a better thermal contact with the soldering iron.
> >
> >
> > Big deal. You need to lower the melting point by using a solder with
> >a higher lead content.
>
> I tend toward braid first to "sop" up enough that then the "sucker"
> can clear the via.

Even the cheap 45W Radio Shack vacuum desoldering iron is better than
solder wick. Wick IS useful for cleaning up pads, when there isn't
enough room for the desoldering tip, and to tin damaged traces for
repairs. it's fin on single, and most double sided boards, but computer
motherboards have a lot of layers to damage.

> (One does assume that the OP cut the cap off the leads first ;-)

There isn't enough room on most motherboards, and it doesn't always
help.

[Phil Allison]

"Cydrome Leader"
> Phil Allison

** Lotsa folks don't think of the easy way to do things - like cutting ALL
the pins on an IC or transistor THEN removing each one individually. This
is waaaay easier than trying to perfectly desolder all the pins at once,
particularly with plated through holes.

If you do not have vacuum de-soldering gear, it is the only sensible way to
get most parts off a PCB.


.... Phil

[Dave U. Random]

"Michael A. Terrell" <mike.t...@earthlink.net> wrote in message
news:evqdnU22xOe49MLN...@earthlink.com...

>
> Anonymous wrote:
>>
>> I'm trying to repair my MSI motherboard by replacing the caps near
the
>> regulators since they are bulging and are most likely defective.
>> However, even at the highest setting of my soldering iron (480
degrees
>> Celcius) I'm unable to liquify the solder. I don't know what kind of
>> solder they're using for motherboards but it's obviously not the kind
>> you can easily manipulate with common DIY tools.
>>
>> Anyone have a trick for solving this problem?
>
>
> What tools are you using? A vacuum desoldering iron is the proper
> tools. Solder wick is a poor second choice.

I'm using an ERSA MS-250 25W soldering iron with a pointed tip. I also
have a simple desoldering iron with a vacuum bulb, I tried using it and
it failed to liquify the solder.

[BeeJ]

Trick?

Cut the cap off at the board level. Use a razor saw if needed or just
a good quality side cutter.
This will reduce the heat mass your biggest enemy.

Make sure your tip is screwed on properly and you used the proper
"lube" on the the threads (if that is the kind) and make sure it is
very tight (tip to iron). Any small amount of disconnect is high
resistance to heat flow.

Use a broader tip since this will increase heat flow to where you need
it. Use a tip with a width close to the pad width. Pointy tips are
not for this kind of work.

Use your solder to to help transfer the heat to the joint and to lower
the melting point of the existing solder.

Use a toothpick to carefully eject the lead. Do not twist the
toothpick as this can lift the pad.

Good luck.

My tech only used the desoldering tool to clean out empty pads never to
remove components. Aerospace trained. He never lifted a pad in ten
years of working for me.

[Michael A. Terrell]

"Dave U. Random" wrote:
>
> "Michael A. Terrell" ?mike.t...@earthlink.net? wrote in message
> news:evqdnU22xOe49MLN...@earthlink.com...
> ?
> ? Anonymous wrote:
> ??
> ?? I'm trying to repair my MSI motherboard by replacing the caps near
> the
> ?? regulators since they are bulging and are most likely defective.
> ?? However, even at the highest setting of my soldering iron (480
> degrees
> ?? Celcius) I'm unable to liquify the solder. I don't know what kind of
> ?? solder they're using for motherboards but it's obviously not the kind
> ?? you can easily manipulate with common DIY tools.
> ??
> ?? Anyone have a trick for solving this problem?
> ?
> ?

> ? What tools are you using? A vacuum desoldering iron is the proper

> ? tools. Solder wick is a poor second choice.

>
> I'm using an ERSA MS-250 25W soldering iron with a pointed tip. I also
> have a simple desoldering iron with a vacuum bulb, I tried using it and
> it failed to liquify the solder.

25W isn't even close to enough heat for that job. The electrolytics
for teh CPU are connected to heavy internal traces. Small irons like
that will damage the board.

[Ross Herbert]

On Sun, 23 Sep 2012 19:37:35 +0000 (UTC), Anonymous
<nob...@remailer.paranoici.org> wrote:

:I'm trying to repair my MSI motherboard by replacing the caps near the

I tend to agree with Michael Terrell.

Unless you use at least a 45W iron you won't get enough heat into the joint to
remove the solder with conventional solder suckers or wick. Because there is no
way to get a razor saw (as someone suggested) in the space available on a MB it
is impossible to cut the leads this way. In most cases you can't cut the leads
with side cutters either, even using fine bladed types, due to lack of
clearance, so this is not an option either. One method I use quite successfully
is to keep the soldering iron tip on the underside of each pin in turn while
putting slight pressure on the same side of the upright electro. You can usually
rock the pin out by a fraction of a mm each time and after several side-to-side
rocks, heating each pin in turn, you can get both pins free. You must be careful
not to apply too much side pressure otherwise you risk stripping the thru-hole
plating. Afterwards it is a simple matter to use new solder (and/or liquid flux)
to complete the cleanout of each thru-hole with a sucker or braid.