Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems.

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Default solder won't come out of hole


For the past couple of hours I've been trying to get the solder out of a
hole. It's a mobo cap, and the other hole sucked right out. It's like an
obstruction. The solder melts with difficulty, but even then I can't get a
dental pick as deep as in the other hole. The cap pulled out easily on both
leads.


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Default solder won't come out of hole

On Tue, 17 Jul 2012 15:53:01 -0400, "Tom Del Rosso"
wrote:

For the past couple of hours I've been trying to get the solder out of a
hole. It's a mobo cap, and the other hole sucked right out. It's like an
obstruction. The solder melts with difficulty, but even then I can't get a
dental pick as deep as in the other hole. The cap pulled out easily on both
leads.


Probably a multilayer board with a big ground plane acting as a heat
sink.

Find some compressed air and a cardboard box.
Get the solder melted with a soldering iron. Use flux.
Point the back side of the PCB towards the cardboard box.
Heat the back side of the PCB with the soldering iron.
Apply the compressed air nozzle to the circuit side.
Remove the soldering iron and very quickly blow some compressed air
through the hold. The dross should land inside the cardboard box.

Also, pointed dental picks don't work well because there's too much
room for the solder in the hole with the tapered tip. Use a paper
clip or stainless piece of wire instead.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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Default solder won't come out of hole

Tom Del Rosso wrote:

For the past couple of hours I've been trying to get the solder out of a
hole. It's a mobo cap, and the other hole sucked right out. It's like an
obstruction. The solder melts with difficulty, but even then I can't get a
dental pick as deep as in the other hole. The cap pulled out easily on both
leads.


add fress solder and try again.

burned up and oxidized tips and traces don't conduct heat well and won't
melt solder in a thick or multilayer board. get some solder wick, the
stuff is magic for things like this.
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Default solder won't come out of hole



"Tom Del Rosso" wrote in message ...


For the past couple of hours I've been trying to get the solder out of a
hole. It's a mobo cap, and the other hole sucked right out. It's like an
obstruction. The solder melts with difficulty, but even then I can't get a
dental pick as deep as in the other hole. The cap pulled out easily on both
leads.

***Start by flowing in some 60/40 - at least if you can attack it at a lower
temperature, it'll take longer to cook the copper/pcb bond.

***If you're using a solder sucker, putting the nozzle off center on the
hole can sometimes draw molten solder out the top of a blocked hole - you
need to do both sides before attacking the blockage.

***Resist the temptation to force a pin through while heating the solder -
almost always takes the through plating with it.

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Default solder won't come out of hole

On Tue, 17 Jul 2012 15:53:01 -0400, "Tom Del Rosso"
wrote:


For the past couple of hours I've been trying to get the solder out of a
hole. It's a mobo cap, and the other hole sucked right out. It's like an
obstruction. The solder melts with difficulty, but even then I can't get a
dental pick as deep as in the other hole. The cap pulled out easily on both
leads.


A Solder Sucker is much better than a dental pick (I've used both).
The solder sucker can be used on one side of the board while the iron
is still on the pad on the other side of the board, which is when the
solder is at its most liquid state.


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Default solder won't come out of hole

On 7/17/2012 1:05 PM, Jeff Liebermann wrote:
On Tue, 17 Jul 2012 15:53:01 -0400, "Tom Del Rosso"
wrote:

For the past couple of hours I've been trying to get the solder out of a
hole. It's a mobo cap, and the other hole sucked right out. It's like an
obstruction. The solder melts with difficulty, but even then I can't get a
dental pick as deep as in the other hole. The cap pulled out easily on both
leads.


Probably a multilayer board with a big ground plane acting as a heat
sink.

You left out the MOST IMPORTANT first step!!!
Wear eye protection!!!
Compressed air and molten solder is a recipe for blindness!!

Find some compressed air and a cardboard box.
Get the solder melted with a soldering iron. Use flux.
Point the back side of the PCB towards the cardboard box.
Heat the back side of the PCB with the soldering iron.
Apply the compressed air nozzle to the circuit side.
Remove the soldering iron and very quickly blow some compressed air
through the hold. The dross should land inside the cardboard box.

Also, pointed dental picks don't work well because there's too much
room for the solder in the hole with the tapered tip. Use a paper
clip or stainless piece of wire instead.


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Default solder won't come out of hole

On Tue, 17 Jul 2012 15:37:31 -0700, mike wrote:

You left out the MOST IMPORTANT first step!!!
Wear eye protection!!!
Compressed air and molten solder is a recipe for blindness!!


Thanks. Y'er right. Goggles or a face mask are a must.

Back in the days when it was worth the effort, I used to remove
components from a PCB by clamping one end of the board in a bench vise
and heating the solder side with a propane torch. When the solder was
good and hot, I would pull the board back and let go. The components
and the solder would go flying in the opposite direction into a
cardboard box. I always wore a face mask, but still managed to burn
myself in obscure places.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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Default solder won't come out of hole

mike wrote:
On 7/17/2012 1:05 PM, Jeff Liebermann wrote:
On Tue, 17 Jul 2012 15:53:01 -0400, "Tom Del Rosso"
wrote:

For the past couple of hours I've been trying to get the solder out of a
hole. It's a mobo cap, and the other hole sucked right out. It's
like an
obstruction. The solder melts with difficulty, but even then I can't
get a
dental pick as deep as in the other hole. The cap pulled out easily
on both
leads.


Probably a multilayer board with a big ground plane acting as a heat
sink.

You left out the MOST IMPORTANT first step!!!
Wear eye protection!!!
Compressed air and molten solder is a recipe for blindness!!

Find some compressed air and a cardboard box.
Get the solder melted with a soldering iron. Use flux.
Point the back side of the PCB towards the cardboard box.
Heat the back side of the PCB with the soldering iron.
Apply the compressed air nozzle to the circuit side.
Remove the soldering iron and very quickly blow some compressed air
through the hold. The dross should land inside the cardboard box.

Also, pointed dental picks don't work well because there's too much
room for the solder in the hole with the tapered tip. Use a paper
clip or stainless piece of wire instead.



Of course there is also the "Whack" method of solder removal. Heat the
item up, and whack it against the bench really quickly.

Alternatively find some very low temperature solder - like Chip-Quick
solder - and melt it into the existing solder. Then it is much easier to
remove.

http://store.curiousinventor.com/chi...ering-kit.html

(not my store!)

John :-#)#

--
(Please post followups or tech enquiries to the newsgroup)
John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
Call (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."
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Default solder won't come out of hole

Tom Del Rosso wrote:

For the past couple of hours I've been trying to get the solder out of a
hole. It's a mobo cap, and the other hole sucked right out. It's like an
obstruction. The solder melts with difficulty, but even then I can't get a
dental pick as deep as in the other hole. The cap pulled out easily on both
leads.


If you have some indium base solder or old leaded solder, reflow it with
that, then suck it out..
Also, I've used my hot air wand to clear the holes.

Jamie



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Default solder won't come out of hole


Cydrome Leader wrote:
Tom Del Rosso wrote:

For the past couple of hours I've been trying to get the solder out
of a hole. It's a mobo cap, and the other hole sucked right out.
It's like an obstruction. The solder melts with difficulty, but
even then I can't get a dental pick as deep as in the other hole.
The cap pulled out easily on both leads.


add fress solder and try again.

burned up and oxidized tips and traces don't conduct heat well and
won't melt solder in a thick or multilayer board. get some solder
wick, the stuff is magic for things like this.


Thanks all.

I got it by applying an iron to one side and the vacuum to the other side.
The Pace desolder station doesn't get hot enough.

I was also using lead-free when I added solder to help it melt. 60/40
worked better.

What's the word on using 60/40 on the replacement?


--

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Default solder won't come out of hole

On 7/17/2012 9:52 PM, Tom Del Rosso wrote:

I was also using lead-free when I added solder to help it melt. 60/40
worked better.

What's the word on using 60/40 on the replacement?


Depending on where you live, it's probably illegal.
But you'd never be prosecuted, because nobody would know...
unless you blabbed it to a few hundred million people on the internet.
;-)


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Default solder won't come out of hole


"Jamie" t wrote in message
...
Tom Del Rosso wrote:

For the past couple of hours I've been trying to get the solder out of a
hole. It's a mobo cap, and the other hole sucked right out. It's like
an obstruction. The solder melts with difficulty, but even then I can't
get a dental pick as deep as in the other hole. The cap pulled out
easily on both leads.


If you have some indium base solder or old leaded solder, reflow it with
that, then suck it out..
Also, I've used my hot air wand to clear the holes.

Jamie




Carefully drill the solder out with a PCB drill slightly smaller than the
hole.
--
Regards,

Chas.

(To email me, replace "xxx" with letters tango papa golf.)


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"Jeff Liebermann" wrote in message
...

On Tue, 17 Jul 2012 15:37:31 -0700, mike wrote:

You left out the MOST IMPORTANT first step!!!
Wear eye protection!!!
Compressed air and molten solder is a recipe for blindness!!


Thanks. Y'er right. Goggles or a face mask are a must.

Back in the days when it was worth the effort, I used to remove
components from a PCB by clamping one end of the board in a bench vise
and heating the solder side with a propane torch. When the solder was
good and hot, I would pull the board back and let go. The components
and the solder would go flying in the opposite direction into a
cardboard box.


***Hot air (electric paint stripper) gun and a stiff paintbush - perfect for
harvesting SMD parts.

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"Tom Del Rosso" wrote in message ...


Cydrome Leader wrote:
Tom Del Rosso wrote:

For the past couple of hours I've been trying to get the solder out
of a hole. It's a mobo cap, and the other hole sucked right out.
It's like an obstruction. The solder melts with difficulty, but
even then I can't get a dental pick as deep as in the other hole.
The cap pulled out easily on both leads.


add fress solder and try again.

burned up and oxidized tips and traces don't conduct heat well and
won't melt solder in a thick or multilayer board. get some solder
wick, the stuff is magic for things like this.


Thanks all.

I got it by applying an iron to one side and the vacuum to the other side.
The Pace desolder station doesn't get hot enough.

I was also using lead-free when I added solder to help it melt. 60/40
worked better.

What's the word on using 60/40 on the replacement?

***Original manufacturers have made remarkable progress in applying RoHS
solder so the components don't fall off after a year or so - unreliability
can rear its ugly head if you pb free solder with the kit on a typical
repair bench.

***If you do get called to book for using 60/40 - just claim that its old
equipment, and you believed that's what it was originally made with.

***If its for hobby purposes and not for resale, that's also exempt.

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"Jamie" wrote in message ...

Tom Del Rosso wrote:

For the past couple of hours I've been trying to get the solder out of a
hole. It's a mobo cap, and the other hole sucked right out. It's like an
obstruction. The solder melts with difficulty, but even then I can't get
a dental pick as deep as in the other hole. The cap pulled out easily on
both leads.


If you have some indium base solder or old leaded solder, reflow it with
that, then suck it out..

***Way back in the days of hybrid CTVs, I remember an old Tandberg telly
that had a "safety pin" style thermal fuse connecting the top cap of the
horizontal sweep tube, just inside the timebase cage was a clip holding a
small roll of low temperature cadmium solder (and a warning label not to use
60/40) for resetting the fuse.

***No doubt the Brussels suits reaction to lead solder would pale into
insignificance compared to cadmium solder!



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On Wed, 18 Jul 2012 14:44:45 +0100, "Ian Field"
wrote:

***Hot air (electric paint stripper) gun and a stiff paintbush - perfect for
harvesting SMD parts.


Yep, but I don't do it that way. With SMD, the problem is identifying
the parts after they've been removed. I usually just want the active
components anyway. So, I have a hot air desoldering station to remove
the chips individually with the help of some liquid flux. The parts
are then bagged and labeled in paper coin bags. A mess of random SMT
components does me no good when I have to spend hours trying to
identify or find a specific component.

Overall, the small parts are so cheap, that I'm questioning whether
it's even worth salvaging the parts. Certainly for RAM, uP, and
possibly BGA chips. However, it's usually easier, cheaper, and takes
less time to just order the parts from a distributor. Also, I suspect
that I only use maybe 1 part for every 100 parts that I scrap.
Recently, I've gone back to just storing the PCB's, and pulling off
parts as needed.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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Default solder won't come out of hole

Jeff Liebermann wrote in
:

On Tue, 17 Jul 2012 15:53:01 -0400, "Tom Del Rosso"
wrote:

For the past couple of hours I've been trying to get the solder out of
a hole. It's a mobo cap, and the other hole sucked right out. It's
like an obstruction. The solder melts with difficulty, but even then
I can't get a dental pick as deep as in the other hole. The cap
pulled out easily on both leads.


Probably a multilayer board with a big ground plane acting as a heat
sink.

Find some compressed air and a cardboard box.
Get the solder melted with a soldering iron. Use flux.
Point the back side of the PCB towards the cardboard box.
Heat the back side of the PCB with the soldering iron.
Apply the compressed air nozzle to the circuit side.
Remove the soldering iron and very quickly blow some compressed air
through the hold. The dross should land inside the cardboard box.

Also, pointed dental picks don't work well because there's too much
room for the solder in the hole with the tapered tip. Use a paper
clip or stainless piece of wire instead.


sounds like a job for Chip-Quik or other low-melting-point solder.

--
Jim Yanik
jyanik
at
localnet
dot com
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Cydrome Leader wrote in
:

Tom Del Rosso wrote:

For the past couple of hours I've been trying to get the solder out
of a hole. It's a mobo cap, and the other hole sucked right out.
It's like an obstruction. The solder melts with difficulty, but even
then I can't get a dental pick as deep as in the other hole. The cap
pulled out easily on both leads.


add fress solder and try again.

burned up and oxidized tips and traces don't conduct heat well and
won't melt solder in a thick or multilayer board. get some solder
wick, the stuff is magic for things like this.


solder wick on a multilayer board can cause internal expansion and
internal,unseen breaking of vias and plated-thru holes.

--
Jim Yanik
jyanik
at
localnet
dot com
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Jeff Liebermann wrote in
:

On Wed, 18 Jul 2012 14:44:45 +0100, "Ian Field"
wrote:

***Hot air (electric paint stripper) gun and a stiff paintbush -
perfect for harvesting SMD parts.


Yep, but I don't do it that way. With SMD, the problem is identifying
the parts after they've been removed. I usually just want the active
components anyway. So, I have a hot air desoldering station to remove
the chips individually with the help of some liquid flux. The parts
are then bagged and labeled in paper coin bags. A mess of random SMT
components does me no good when I have to spend hours trying to
identify or find a specific component.

Overall, the small parts are so cheap, that I'm questioning whether
it's even worth salvaging the parts. Certainly for RAM, uP, and
possibly BGA chips. However, it's usually easier, cheaper, and takes
less time to just order the parts from a distributor. Also, I suspect
that I only use maybe 1 part for every 100 parts that I scrap.
Recently, I've gone back to just storing the PCB's, and pulling off
parts as needed.


I would be VERY leery of a BGA "re-used";
I don't believe one can get the inner pads to solder reliably.

--
Jim Yanik
jyanik
at
localnet
dot com


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"Ian Field" wrote in
:



"Tom Del Rosso" wrote in message ...


Cydrome Leader wrote:
Tom Del Rosso wrote:

For the past couple of hours I've been trying to get the solder out
of a hole. It's a mobo cap, and the other hole sucked right out.
It's like an obstruction. The solder melts with difficulty, but
even then I can't get a dental pick as deep as in the other hole.
The cap pulled out easily on both leads.


add fress solder and try again.

burned up and oxidized tips and traces don't conduct heat well and
won't melt solder in a thick or multilayer board. get some solder
wick, the stuff is magic for things like this.


Thanks all.

I got it by applying an iron to one side and the vacuum to the other
side. The Pace desolder station doesn't get hot enough.

I was also using lead-free when I added solder to help it melt. 60/40
worked better.

What's the word on using 60/40 on the replacement?

***Original manufacturers have made remarkable progress in applying
RoHS solder so the components don't fall off after a year or so -
unreliability can rear its ugly head if you pb free solder with the
kit on a typical repair bench.

***If you do get called to book for using 60/40 - just claim that its
old equipment, and you believed that's what it was originally made
with.

***If its for hobby purposes and not for resale, that's also exempt.



if you sucked out the applied solder,there's probably little leaded solder
left to "harm" anyone. maybe not even detectable with their usual tests.

And I'm not going to tell on you. :-)

--
Jim Yanik
jyanik
at
localnet
dot com
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"Ian Field" wrote in
:



"Jamie" wrote in message ...

Tom Del Rosso wrote:

For the past couple of hours I've been trying to get the solder out
of a hole. It's a mobo cap, and the other hole sucked right out.
It's like an obstruction. The solder melts with difficulty, but even
then I can't get a dental pick as deep as in the other hole. The cap
pulled out easily on both leads.


If you have some indium base solder or old leaded solder, reflow it
with that, then suck it out..

***Way back in the days of hybrid CTVs, I remember an old Tandberg
telly that had a "safety pin" style thermal fuse connecting the top
cap of the horizontal sweep tube, just inside the timebase cage was a
clip holding a small roll of low temperature cadmium solder (and a
warning label not to use 60/40) for resetting the fuse.

***No doubt the Brussels suits reaction to lead solder would pale into
insignificance compared to cadmium solder!



ACH,the HORROR!!!!!

--
Jim Yanik
jyanik
at
localnet
dot com
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"Jeff Liebermann" wrote in message
...

On Wed, 18 Jul 2012 14:44:45 +0100, "Ian Field"
wrote:

***Hot air (electric paint stripper) gun and a stiff paintbush - perfect
for
harvesting SMD parts.


Yep, but I don't do it that way. With SMD, the problem is identifying
the parts after they've been removed. I usually just want the active
components anyway.

***One thing I particularly go after is the larger multilayer SMD chip
capacitors, surprisingly large values in surprisingly small package. Also
the larger discrete semiconductors, the TO251/252 fit less veroboard space
than a TO92.

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"Jim Yanik" wrote in message
4...

"Ian Field" wrote in
:



"Jamie" wrote in message ...

Tom Del Rosso wrote:

For the past couple of hours I've been trying to get the solder out
of a hole. It's a mobo cap, and the other hole sucked right out.
It's like an obstruction. The solder melts with difficulty, but even
then I can't get a dental pick as deep as in the other hole. The cap
pulled out easily on both leads.


If you have some indium base solder or old leaded solder, reflow it
with that, then suck it out..

***Way back in the days of hybrid CTVs, I remember an old Tandberg
telly that had a "safety pin" style thermal fuse connecting the top
cap of the horizontal sweep tube, just inside the timebase cage was a
clip holding a small roll of low temperature cadmium solder (and a
warning label not to use 60/40) for resetting the fuse.

***No doubt the Brussels suits reaction to lead solder would pale into
insignificance compared to cadmium solder!



ACH,the HORROR!!!!!

***WEEE wasn't even a glint in someone's eye back then - thousands of those
sets went to landfill with the roll of cadmium solder untouched.

***Round about WW2 time - ish; component leads weren't tinned - they were
cad plated.

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Jim Yanik wrote:

I would be VERY leery of a BGA "re-used";
I don't believe one can get the inner pads to solder reliably.



It's done all the time, but you have to 'reball' the chip first.
Then it's exactly like using a new part. Military & medical have to
have the lead free crap repalced with real solder balls. You can buy
the balls and simple tooling on Ebay for very little money to reball
them yourself.


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Chas wrote:

"Jamie" t wrote in message
...
Tom Del Rosso wrote:

For the past couple of hours I've been trying to get the solder out of a
hole. It's a mobo cap, and the other hole sucked right out. It's like
an obstruction. The solder melts with difficulty, but even then I can't
get a dental pick as deep as in the other hole. The cap pulled out
easily on both leads.


If you have some indium base solder or old leaded solder, reflow it with
that, then suck it out..
Also, I've used my hot air wand to clear the holes.

Jamie




Carefully drill the solder out with a PCB drill slightly smaller than the
hole.



And take out part of the via (your 'hole') in the process? A board
with damaged vias would be scrapped at the factory.
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Default solder won't come out of hole

Tom Del Rosso wrote:


For the past couple of hours I've been trying to get the solder out of a
hole. It's a mobo cap, and the other hole sucked right out. It's like an
obstruction. The solder melts with difficulty, but even then I can't get
a
dental pick as deep as in the other hole. The cap pulled out easily on
both leads.


It probably is lead-free solder. Dilute the solder with tin-lead solder,
which will lower the melting point. Then, use a solder sucker, solder
wick or what have you to clear the hole.

Jon
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On Wed, 18 Jul 2012 11:50:18 -0500, Jim Yanik
wrote:

I would be VERY leery of a BGA "re-used";
I don't believe one can get the inner pads to solder reliably.


True. It's NOT easily done. I've only tried one large BGA chip and
it didn't work. However, I've successfully replacing two smaller BGA
wireless chips. Instead of reballing, I used solder paste on both the
chip and the PCB. Then reflow with a hot air desoldering station.
Here's the general idea:
http://www.youtube.com/watch?v=JB1InDsWCjQ
except that I used solder paste instead of trying to make solder balls
on the BGA chip. Note the copious use of (paste) flux. (Incidentally,
the cell phone is a Qualcomm QCP-6035).

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
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Skype: JeffLiebermann AE6KS 831-336-2558
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Default solder won't come out of hole

On Wed, 18 Jul 2012 11:45:43 -0500, Jim Yanik
wrote:

Jeff Liebermann wrote in

(...)
Also, pointed dental picks don't work well because there's too much
room for the solder in the hole with the tapered tip. Use a paper
clip or stainless piece of wire instead.


sounds like a job for Chip-Quik or other low-melting-point solder.


I've never tried the stuff. The problem is that dross (oxidized
solder) will not flow, wick, or can be easily blown through the hole.
All that's really needed is some 60-40 and a little flux. Once the
dross is gone or disolved, the solder should flow and the hole clear
easily. Chip-Quik sounds like an interesting way to do a whole IC at
once, but I have a hot air desoldering station that works.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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Default solder won't come out of hole

On Wed, 18 Jul 2012 19:56:05 +1000, "Chas" wrote:

Carefully drill the solder out with a PCB drill slightly smaller than the
hole.


Bad idea. That usually rips out the plating in the hole. The drill
collects a mix of solder and copper around the outside, which galls
together with the solder plating inside the hole, and eventually rips
out the plating. Even if you can find a workable drill, keeping the
drill exactly perpendicular to the PCB is quite difficult.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558


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Default solder won't come out of hole



"Jeff Liebermann" wrote in message
...

On Wed, 18 Jul 2012 19:56:05 +1000, "Chas" wrote:

Carefully drill the solder out with a PCB drill slightly smaller than the
hole.


Bad idea. That usually rips out the plating in the hole. The drill
collects a mix of solder and copper around the outside, which galls
together with the solder plating inside the hole, and eventually rips
out the plating. Even if you can find a workable drill, keeping the
drill exactly perpendicular to the PCB is quite difficult.


***I'm with those against drilling - maybe with a drill bit *MUCH* smaller
than the hole, but if the cutting tip hits a hard obstruction it'll take
chunks out of the through plate wall in preference.

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Default solder won't come out of hole

Chas wrote:

"Jamie" t wrote in message
...

Tom Del Rosso wrote:


For the past couple of hours I've been trying to get the solder out of a
hole. It's a mobo cap, and the other hole sucked right out. It's like
an obstruction. The solder melts with difficulty, but even then I can't
get a dental pick as deep as in the other hole. The cap pulled out
easily on both leads.



If you have some indium base solder or old leaded solder, reflow it with
that, then suck it out..
Also, I've used my hot air wand to clear the holes.

Jamie





Carefully drill the solder out with a PCB drill slightly smaller than the
hole.

you must be careful to not remove the vias conductor when doing so.

Jamie

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Default solder won't come out of hole

Jim Yanik wrote in message
4...
"Ian Field" wrote in
:



"Tom Del Rosso" wrote in message ...


Cydrome Leader wrote:
Tom Del Rosso wrote:

For the past couple of hours I've been trying to get the solder out
of a hole. It's a mobo cap, and the other hole sucked right out.
It's like an obstruction. The solder melts with difficulty, but
even then I can't get a dental pick as deep as in the other hole.
The cap pulled out easily on both leads.

add fress solder and try again.

burned up and oxidized tips and traces don't conduct heat well and
won't melt solder in a thick or multilayer board. get some solder
wick, the stuff is magic for things like this.


Thanks all.

I got it by applying an iron to one side and the vacuum to the other
side. The Pace desolder station doesn't get hot enough.

I was also using lead-free when I added solder to help it melt. 60/40
worked better.

What's the word on using 60/40 on the replacement?

***Original manufacturers have made remarkable progress in applying
RoHS solder so the components don't fall off after a year or so -
unreliability can rear its ugly head if you pb free solder with the
kit on a typical repair bench.

***If you do get called to book for using 60/40 - just claim that its
old equipment, and you believed that's what it was originally made
with.

***If its for hobby purposes and not for resale, that's also exempt.



if you sucked out the applied solder,there's probably little leaded solder
left to "harm" anyone. maybe not even detectable with their usual tests.

And I'm not going to tell on you. :-)

--
Jim Yanik
jyanik
at
localnet
dot com




From someone in a high-reliability RoHS derogated industry, it is quite a
work-up to test for elemental lead on the "tinning" of component leads.
Their problem is false-manifest/specced components that are bought supposed
to be the now expensive leaded tining , actually being now-standard PbF
components and fraudulently traded.


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"Jamie" wrote in message ...

Chas wrote:

"Jamie" t wrote in
message ...

Tom Del Rosso wrote:


For the past couple of hours I've been trying to get the solder out of a
hole. It's a mobo cap, and the other hole sucked right out. It's like
an obstruction. The solder melts with difficulty, but even then I can't
get a dental pick as deep as in the other hole. The cap pulled out
easily on both leads.



If you have some indium base solder or old leaded solder, reflow it with
that, then suck it out..
Also, I've used my hot air wand to clear the holes.

Jamie





Carefully drill the solder out with a PCB drill slightly smaller than the
hole.

you must be careful to not remove the vias conductor when doing so.

Jamie

***Easier said than done!



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Default solder won't come out of hole

Ian Field wrote:



"Jamie" wrote in message ...

Chas wrote:

"Jamie" t wrote in
message ...

Tom Del Rosso wrote:


For the past couple of hours I've been trying to get the solder out
of a hole. It's a mobo cap, and the other hole sucked right out.
It's like an obstruction. The solder melts with difficulty, but
even then I can't get a dental pick as deep as in the other hole.
The cap pulled out easily on both leads.



If you have some indium base solder or old leaded solder, reflow it
with that, then suck it out..
Also, I've used my hot air wand to clear the holes.

Jamie





Carefully drill the solder out with a PCB drill slightly smaller than
the hole.


you must be careful to not remove the vias conductor when doing so.

Jamie

***Easier said than done!

I have a tip I made for my Hot air wand that has a hypodermic needle on
it. I heat it up and hit the air switch and push it through the hole.

Jamie..

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Default solder won't come out of hole

Jamie t wrote in message
...
Ian Field wrote:



"Jamie" wrote in message ...

Chas wrote:

"Jamie" t wrote in
message ...

Tom Del Rosso wrote:


For the past couple of hours I've been trying to get the solder out
of a hole. It's a mobo cap, and the other hole sucked right out.
It's like an obstruction. The solder melts with difficulty, but
even then I can't get a dental pick as deep as in the other hole.
The cap pulled out easily on both leads.



If you have some indium base solder or old leaded solder, reflow it
with that, then suck it out..
Also, I've used my hot air wand to clear the holes.

Jamie





Carefully drill the solder out with a PCB drill slightly smaller than
the hole.


you must be careful to not remove the vias conductor when doing so.

Jamie

***Easier said than done!

I have a tip I made for my Hot air wand that has a hypodermic needle on
it. I heat it up and hit the air switch and push it through the hole.

Jamie..



What is that like with PbF ?. Hypos use stainless steel and I find stainless
steel is a reasonable identifier of PbF as it determinedly sticks to
stainless steel, does the capilliary bore of the needle then totally block
with solder?


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Default solder won't come out of hole



"Jamie" wrote in message ...

Ian Field wrote:



"Jamie" wrote in message ...

Chas wrote:

"Jamie" t wrote in
message ...

Tom Del Rosso wrote:


For the past couple of hours I've been trying to get the solder out of
a hole. It's a mobo cap, and the other hole sucked right out. It's
like an obstruction. The solder melts with difficulty, but even then I
can't get a dental pick as deep as in the other hole. The cap pulled
out easily on both leads.



If you have some indium base solder or old leaded solder, reflow it with
that, then suck it out..
Also, I've used my hot air wand to clear the holes.

Jamie





Carefully drill the solder out with a PCB drill slightly smaller than the
hole.


you must be careful to not remove the vias conductor when doing so.

Jamie

***Easier said than done!

I have a tip I made for my Hot air wand that has a hypodermic needle on
it. I heat it up and hit the air switch and push it through the hole.

Jamie..

***Many years ago I made an SMD harvesting machine out of a portable LPG
heater and an old fridge compressor.

***The copper pipe was coiled and stuffed behind the guard on the heater,
right in front of the burners. A carburetor jet was peened into the end of
the copper pipe to produce a fierce jet of very hot air.

***A cardboard box on its side opposite the nozzle caught most of the low
flying SMDs, but I had to abandon it because it was just too hot sitting so
close to the heater.

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Default solder won't come out of hole


N_Cook wrote:

Jamie t wrote:

I have a tip I made for my Hot air wand that has a hypodermic needle on
it. I heat it up and hit the air switch and push it through the hole.

Jamie..


What is that like with PbF ?. Hypos use stainless steel and I find stainless
steel is a reasonable identifier of PbF as it determinedly sticks to
stainless steel, does the capilliary bore of the needle then totally block
with solder?



According to what he wrote he is forcing hot air through the needele, so
solder can't get inside it.
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N_Cook wrote:

Jamie t wrote in message
...

Ian Field wrote:



"Jamie" wrote in message ...

Chas wrote:


"Jamie" t wrote in
message ...


Tom Del Rosso wrote:



For the past couple of hours I've been trying to get the solder out
of a hole. It's a mobo cap, and the other hole sucked right out.
It's like an obstruction. The solder melts with difficulty, but
even then I can't get a dental pick as deep as in the other hole.
The cap pulled out easily on both leads.



If you have some indium base solder or old leaded solder, reflow it
with that, then suck it out..
Also, I've used my hot air wand to clear the holes.

Jamie





Carefully drill the solder out with a PCB drill slightly smaller than
the hole.

you must be careful to not remove the vias conductor when doing so.

Jamie

***Easier said than done!


I have a tip I made for my Hot air wand that has a hypodermic needle on
it. I heat it up and hit the air switch and push it through the hole.

Jamie..




What is that like with PbF ?. Hypos use stainless steel and I find stainless
steel is a reasonable identifier of PbF as it determinedly sticks to
stainless steel, does the capilliary bore of the needle then totally block
with solder?


you have your air pump when when doing so. No, it does not stick to the
needles I use. In fact, I can just shake it and the solder will fall off.

Jamie

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