Desoldering wattage and tip size for tight multilayer vias
 

This Saturday I replaced seven popped Nichicon electrolytics
in my iMac G5; it took me nearly five hours of intense battling
with too-tight hole sizes and high-thermal conductivity planes
but the job got done and the fix worked. Has anyone worked
on this planar and can comment? What wattage and tip sizes
worked for you? I used a 65 watt iron and ground the tip into
various chisels and angled points, used excess solder and flux
and tried an amount of preheating but it really was a _bitch_
to do. I kinda doubt the board was made for repairing.

Michael

Desoldering wattage and tip size for tight multilayer vias
 

msg wrote:
This Saturday I replaced seven popped Nichicon electrolytics
in my iMac G5; it took me nearly five hours of intense battling
with too-tight hole sizes and high-thermal conductivity planes
but the job got done and the fix worked. Has anyone worked
on this planar and can comment? What wattage and tip sizes
worked for you? I used a 65 watt iron and ground the tip into
various chisels and angled points, used excess solder and flux
and tried an amount of preheating but it really was a _bitch_
to do. I kinda doubt the board was made for repairing.

Michael


The heatsinking effect of planes can be a real issue. I use a 140W
Weller soldering gun for motherboard capacitor replacement, it's the
only thing I've found that puts down enough heat to remove the caps
without ripping up traces.

Desoldering wattage and tip size for tight multilayer vias
 

James Sweet wrote:


msg wrote:

This Saturday I replaced seven popped Nichicon electrolytics
in my iMac G5; it took me nearly five hours of intense battling
with too-tight hole sizes and high-thermal conductivity planes
but the job got done and the fix worked. Has anyone worked
on this planar and can comment? What wattage and tip sizes
worked for you? I used a 65 watt iron and ground the tip into
various chisels and angled points, used excess solder and flux
and tried an amount of preheating but it really was a _bitch_
to do. I kinda doubt the board was made for repairing.

Michael



The heatsinking effect of planes can be a real issue. I use a 140W
Weller soldering gun for motherboard capacitor replacement, it's the
only thing I've found that puts down enough heat to remove the caps
without ripping up traces.

Indeed. I neglected to mention that I cranked up the wattage with
a variac to about 90W but that is nowhere near what you use ;)

Michael

Desoldering wattage and tip size for tight multilayer vias
 

msg Inscribed thus:

James Sweet wrote:


msg wrote:

This Saturday I replaced seven popped Nichicon electrolytics
in my iMac G5; it took me nearly five hours of intense battling
with too-tight hole sizes and high-thermal conductivity planes
but the job got done and the fix worked. Has anyone worked
on this planar and can comment? What wattage and tip sizes
worked for you? I used a 65 watt iron and ground the tip into
various chisels and angled points, used excess solder and flux
and tried an amount of preheating but it really was a _bitch_
to do. I kinda doubt the board was made for repairing.

Michael



The heatsinking effect of planes can be a real issue. I use a 140W
Weller soldering gun for motherboard capacitor replacement, it's the
only thing I've found that puts down enough heat to remove the caps
without ripping up traces.

Indeed. I neglected to mention that I cranked up the wattage with
a variac to about 90W but that is nowhere near what you use ;)

Michael

Hot air preheating works wonders. I use a hot air paint stripper gun to
preheat an area first before then desoldering the cap. Usually they
come out of the board quite cleanly but some manufacturers bend the
leads after insertion into the pcb, which can be a pain.

--
Best Reagrds:
Baron.

Desoldering wattage and tip size for tight multilayer vias
 

Baron wrote:
msg Inscribed thus:

James Sweet wrote:

msg wrote:

This Saturday I replaced seven popped Nichicon electrolytics
in my iMac G5; it took me nearly five hours of intense battling
with too-tight hole sizes and high-thermal conductivity planes
but the job got done and the fix worked. Has anyone worked
on this planar and can comment? What wattage and tip sizes
worked for you? I used a 65 watt iron and ground the tip into
various chisels and angled points, used excess solder and flux
and tried an amount of preheating but it really was a _bitch_
to do. I kinda doubt the board was made for repairing.

Michael


The heatsinking effect of planes can be a real issue. I use a 140W
Weller soldering gun for motherboard capacitor replacement, it's the
only thing I've found that puts down enough heat to remove the caps
without ripping up traces.
Indeed. I neglected to mention that I cranked up the wattage with
a variac to about 90W but that is nowhere near what you use ;)

Michael

Hot air preheating works wonders. I use a hot air paint stripper gun to
preheat an area first before then desoldering the cap. Usually they
come out of the board quite cleanly but some manufacturers bend the
leads after insertion into the pcb, which can be a pain.



That's a great idea, I'll have to give it a try next time. Just have to
be careful not to overdo it and cause SMT parts to drop off the board.

Desoldering wattage and tip size for tight multilayer vias
 

Baron wrote in message
...
msg Inscribed thus:

James Sweet wrote:


msg wrote:

This Saturday I replaced seven popped Nichicon electrolytics
in my iMac G5; it took me nearly five hours of intense battling
with too-tight hole sizes and high-thermal conductivity planes
but the job got done and the fix worked. Has anyone worked
on this planar and can comment? What wattage and tip sizes
worked for you? I used a 65 watt iron and ground the tip into
various chisels and angled points, used excess solder and flux
and tried an amount of preheating but it really was a _bitch_
to do. I kinda doubt the board was made for repairing.

Michael



The heatsinking effect of planes can be a real issue. I use a 140W
Weller soldering gun for motherboard capacitor replacement, it's the
only thing I've found that puts down enough heat to remove the caps
without ripping up traces.

Indeed. I neglected to mention that I cranked up the wattage with
a variac to about 90W but that is nowhere near what you use ;)

Michael

Hot air preheating works wonders. I use a hot air paint stripper gun to
preheat an area first before then desoldering the cap. Usually they
come out of the board quite cleanly but some manufacturers bend the
leads after insertion into the pcb, which can be a pain.

--
Best Reagrds:
Baron.


My tool for that is a dart with a bolt exchanged for the flight.
Without heating, excavate around the solder with the dart until you can
lever the pin up.
But then I continue on , using the hot-air only.
Another recently discovered aid for this process.
I saw a plumber using some woven glass mat to protect a cupboard before
soldering.
As I had plenty of GRP grade woven mat I glued together 4 bits of sheet of
that , using contact adhesive (discolours but holds together on hot air
heating).
Cut a hole to match the area of interest and lightly clamp the mat to the
board , mounted in a vice with protected jaws.

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

Desoldering wattage and tip size for tight multilayer vias
 

James Sweet wrote in news:Lye1k.2159$Yx.1418
@trndny08:


Baron wrote:
msg Inscribed thus:

James Sweet wrote:

msg wrote:

This Saturday I replaced seven popped Nichicon electrolytics
in my iMac G5; it took me nearly five hours of intense battling
with too-tight hole sizes and high-thermal conductivity planes
but the job got done and the fix worked. Has anyone worked
on this planar and can comment? What wattage and tip sizes
worked for you? I used a 65 watt iron and ground the tip into
various chisels and angled points, used excess solder and flux
and tried an amount of preheating but it really was a _bitch_
to do. I kinda doubt the board was made for repairing.

Michael


The heatsinking effect of planes can be a real issue. I use a 140W
Weller soldering gun for motherboard capacitor replacement, it's the
only thing I've found that puts down enough heat to remove the caps
without ripping up traces.
Indeed. I neglected to mention that I cranked up the wattage with
a variac to about 90W but that is nowhere near what you use ;)

Michael

Hot air preheating works wonders. I use a hot air paint stripper gun to
preheat an area first before then desoldering the cap. Usually they
come out of the board quite cleanly but some manufacturers bend the
leads after insertion into the pcb, which can be a pain.



That's a great idea, I'll have to give it a try next time. Just have to
be careful not to overdo it and cause SMT parts to drop off the board.

I have built dams out of paper to protect nearby parts from the hot air.
Held the paper on the board with alligator clips.

Works fine. Also a good temperature indicator. If the paper chars too much,
your air is too hot.

caveat: I was playing with an old pcb, stripping it of parts with my hot
air gun. One of the electrolytic caps got caught in the guns nozzle.

Before I could shake it out, BANG. Small jet of flames. Shell of cap
flying across the room.

In other words "avoid overheating electrolytics, they can explode."







--
bz 73 de N5BZ k

please pardon my infinite ignorance, the set-of-things-I-do-not-know is an
infinite set.

remove ch100-5 to avoid spam trap

Desoldering wattage and tip size for tight multilayer vias
 

On Mon, 02 Jun 2008 14:11:32 -0500, msg wrote:

This Saturday I replaced seven popped Nichicon electrolytics
in my iMac G5; it took me nearly five hours of intense battling
with too-tight hole sizes and high-thermal conductivity planes
but the job got done and the fix worked. Has anyone worked
on this planar and can comment? What wattage and tip sizes
worked for you? I used a 65 watt iron and ground the tip into
various chisels and angled points, used excess solder and flux
and tried an amount of preheating but it really was a _bitch_
to do. I kinda doubt the board was made for repairing.

Michael

I wouldn't even attempt to do this without a temperature controlled
soldering station. You need a lot of power, but with no temperature
control, you're likely to over heat the board and lift traces. It's
also critical to have a clean properly tinned tip.
Andy Cuffe

Desoldering wattage and tip size for tight multilayer vias
 

Andy Cuffe wrote:
On Mon, 02 Jun 2008 14:11:32 -0500, msg wrote:

This Saturday I replaced seven popped Nichicon electrolytics
in my iMac G5; it took me nearly five hours of intense battling
with too-tight hole sizes and high-thermal conductivity planes
but the job got done and the fix worked. Has anyone worked
on this planar and can comment? What wattage and tip sizes
worked for you? I used a 65 watt iron and ground the tip into
various chisels and angled points, used excess solder and flux
and tried an amount of preheating but it really was a _bitch_
to do. I kinda doubt the board was made for repairing.

Michael

I wouldn't even attempt to do this without a temperature controlled
soldering station. You need a lot of power, but with no temperature
control, you're likely to over heat the board and lift traces. It's
also critical to have a clean properly tinned tip.
Andy Cuffe




I have one, but it doesn't provide enough heat. 140W gun works great,
haven't damaged a board yet, I've been soldering for a long time though.

Desoldering wattage and tip size for tight multilayer vias
 

In article , wrote:
On Mon, 02 Jun 2008 14:11:32 -0500, msg wrote:

This Saturday I replaced seven popped Nichicon electrolytics
in my iMac G5; it took me nearly five hours of intense battling
with too-tight hole sizes and high-thermal conductivity planes
but the job got done and the fix worked. Has anyone worked
on this planar and can comment? What wattage and tip sizes
worked for you? I used a 65 watt iron and ground the tip into
various chisels and angled points, used excess solder and flux
and tried an amount of preheating but it really was a _bitch_
to do. I kinda doubt the board was made for repairing.

Michael

I wouldn't even attempt to do this without a temperature controlled
soldering station. You need a lot of power, but with no temperature
control, you're likely to over heat the board and lift traces. It's
also critical to have a clean properly tinned tip.
Andy Cuffe



Having a Weller miniature iron with 80 watts is sure nice. Sometimes I combine heats from
the 3 outputs. Desolder, solderer, and hot air. I have used 2 irons before.
For the rough things sometimes I also use a Bic lighter against the iron for a afterburner effect.
The RS 250 watt gun, then the torch.

I got so tired of watching the game last night, I got to the point I just wanted anybody to win so it was all
over....

greg

Lets go Pens

Desoldering wattage and tip size for tight multilayer vias
 

bz wrote:

caveat: I was playing with an old pcb, stripping it of parts with my hot
air gun. One of the electrolytic caps got caught in the guns nozzle.

Before I could shake it out, BANG. Small jet of flames. Shell of cap
flying across the room.

In other words "avoid overheating electrolytics, they can explode."


Wimp! ;-)


--
http://improve-usenet.org/index.html

If you have broadband, your ISP may have a NNTP news server included in
your account: http://www.usenettools.net/ISP.htm

Sporadic E is the Earth's aluminum foil beanie for the 'global warming'
sheep.

Desoldering wattage and tip size for tight multilayer vias
 

James Sweet Inscribed thus:


Baron wrote:
msg Inscribed thus:

James Sweet wrote:

msg wrote:

This Saturday I replaced seven popped Nichicon electrolytics
in my iMac G5; it took me nearly five hours of intense battling
with too-tight hole sizes and high-thermal conductivity planes
but the job got done and the fix worked. Has anyone worked
on this planar and can comment? What wattage and tip sizes
worked for you? I used a 65 watt iron and ground the tip into
various chisels and angled points, used excess solder and flux
and tried an amount of preheating but it really was a _bitch_
to do. I kinda doubt the board was made for repairing.

Michael


The heatsinking effect of planes can be a real issue. I use a 140W
Weller soldering gun for motherboard capacitor replacement, it's
the only thing I've found that puts down enough heat to remove the
caps without ripping up traces.
Indeed. I neglected to mention that I cranked up the wattage with
a variac to about 90W but that is nowhere near what you use ;)

Michael

Hot air preheating works wonders. I use a hot air paint stripper gun
to preheat an area first before then desoldering the cap. Usually
they come out of the board quite cleanly but some manufacturers bend
the leads after insertion into the pcb, which can be a pain.



That's a great idea, I'll have to give it a try next time. Just have
to be careful not to overdo it and cause SMT parts to drop off the
board.

I have found that often SMT parts are glued down and are a right pig to
get off the board, particularly if its a part that you want to
salvage !

--
Best Reagrds:
Baron.

Desoldering wattage and tip size for tight multilayer vias
 

That's a great idea, I'll have to give it a try next time. Just have
to be careful not to overdo it and cause SMT parts to drop off the
board.

I have found that often SMT parts are glued down and are a right pig to
get off the board, particularly if its a part that you want to
salvage !


Often yes, but when you want it to stay on the board, it'll fall right
off! Don't ask me how I know that :)