general question: mainboard caps

[Michael]

Hello,

I've got a couple of Intel boards (D865PERL) that have one bad
electrolytic capacitor each. One board stopped working; the other
still works, but has a bulging cap close to the CPU area. (Pics not
yet available.)

Is desoldering these caps straightforward? Any special precautions
re: multi-layered PCB traces? Any special gotchas to keep in mind
when ordering replacement caps from say Mouser?

Thanks,

Michael

 

[Jeffrey Angus]

On 9/20/2010 2:52 PM, Michael wrote:

Hello,

I've got a couple of Intel boards (D865PERL) that have one bad
electrolytic capacitor each. One board stopped working; the other
still works, but has a bulging cap close to the CPU area. (Pics not
yet available.)

Is desoldering these caps straightforward? Any special precautions
re: multi-layered PCB traces? Any special gotchas to keep in mind
when ordering replacement caps from say Mouser?

I fully recapped a pair of Dell Optoplex GX-280 mother boards.
About 15 or so caps per board.

Using a vacuum desoldering tool is the best method, but you can
remove the caps but using a wide enough tip to hit both leads
at the same time, then go back and clean the solder out of the holes
with a piece of stainless steel like a dental pick. Melt, stuff,
let cool and remove.

On the caps look for "low esr" and 105C temperature range. I try to
buy Nichicon caps by default. At $1 or so apiece, it's not worth saving
a few cents to get a crap cap that won't last.

Jeff

 

[N_Cook]

Jeffrey Angus <jangus@suddenlink.net> wrote in message
news:4c97d7eb$0$14818$bbae4d71@news.suddenlink.net...

On 9/20/2010 2:52 PM, Michael wrote:
Hello,

I've got a couple of Intel boards (D865PERL) that have one bad
electrolytic capacitor each. One board stopped working; the other
still works, but has a bulging cap close to the CPU area. (Pics not
yet available.)

Is desoldering these caps straightforward? Any special precautions
re: multi-layered PCB traces? Any special gotchas to keep in mind
when ordering replacement caps from say Mouser?

I fully recapped a pair of Dell Optoplex GX-280 mother boards.
About 15 or so caps per board.

Using a vacuum desoldering tool is the best method, but you can
remove the caps but using a wide enough tip to hit both leads
at the same time, then go back and clean the solder out of the holes
with a piece of stainless steel like a dental pick. Melt, stuff,
let cool and remove.

On the caps look for "low esr" and 105C temperature range. I try to
buy Nichicon caps by default. At $1 or so apiece, it's not worth saving
a few cents to get a crap cap that won't last.

Jeff

If you can clamp to the cap and pull at the same time it helps, I use a
surgical instrument like arterial forceps but longer opening arms and full
gripping teeth (retraction clamp?).
For the cleaning out of holes I made up a set of needle probes from
different sized st/st sewing needles glued into ballpoint pen barrels or
into drilled dowel

 

[N_Cook]

No 16 of part of my tool kit is the specific clamp
http://www.diversed.fsnet.co.uk/tools_s.jpg
if anyone should happen to know the medical name for.
Number 17 are surgical terminology "Spencer Wells" , good for heatsinking
etc

 

[N_Cook]

goggling , probably Baby-Allis forceps

 

[Jeff Liebermann]

On Mon, 20 Sep 2010 12:52:38 -0700 (PDT), Michael
<mrdarrett@gmail.com> wrote:

I've got a couple of Intel boards (D865PERL) that have one bad
electrolytic capacitor each. One board stopped working; the other
still works, but has a bulging cap close to the CPU area. (Pics not
yet available.)

My experience is that if you have the usual 8-10 identical capacitors
on the motherboard, and one is visibly defective, then the others are
highly likely to fail very soon. I replace *ALL* the caps of a
specific type. In particular, the caps around the CPU tend to die,
because of the heat and the high ripple current. Typically, I'll
replace 10 to 15 caps.

Is desoldering these caps straightforward?

It varies. Some boards are very easy to unsolder. Others have
smaller holes for the leaded parts and are more difficult. A vacuum
desoldering station is best. Use plenty of heat and some liquid flux
so that you don't pull the plated thru hole out with the capacitor. If
you see a copper colored ring around a capacitor lead, you've probably
killed the board.

Any special precautions
re: multi-layered PCB traces?

If you don't have a tip that will heat both leads at the same time, or
don't have 3 arms so that you can use two soldering irons, all is not
lost. I heat up one lead, and rock the capacitor in the opposite
direction. After it moves a little, I heat the other lead, and rock
it in the opposite direction. Don't use brute force or you'll rip out
the plated through holes. Eventually, it comes out.

One lead is usually grounded where the large copper area acts as an
effective heat sink. This lead will be more difficult to unsolder
than the hot lead (usually +). I use a big, wide (1/4"), hot (850C),
chisel tip. Plenty of heat, and work fast. This will take some
practice. Find an old PCB and practice a little before attacking the
Intel motherboard.

Any special gotchas to keep in mind
when ordering replacement caps from say Mouser?

105C Low-ESR. Watch the case dimensions and lead spacing. If it will
fit, try to buy the next higher voltage rating. I'm partial to
Panasonic but will use Rubycon. Digikey, Mouser, and eBay (in that
order). I sometimes use polymer caps as replacements, when the
motherboard is worth fixing and the customer doesn't care about the
cost. Also, think about buying an ESR tester if you're going to make
a habit of this.

<http://www.badcaps.net>
<http://www.afrotechmods.com/groovy/capacitor_replacement/capacitor_replacement.htm>
<http://en.wikipedia.org/wiki/Capacitor_plague>
<http://www.capacitorlab.com>


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

 

[Michael]

On Sep 21, 9:44 am, Jeff Liebermann <je...@cruzio.com> wrote:

On Mon, 20 Sep 2010 12:52:38 -0700 (PDT), Michael

mrdarr...@gmail.com> wrote:
I've got a couple of Intel boards (D865PERL) that have one bad
electrolytic capacitor each.  One board stopped working; the other
still works, but has a bulging cap close to the CPU area.  (Pics not
yet available.)

My experience is that if you have the usual 8-10 identical capacitors
on the motherboard, and one is visibly defective, then the others are
highly likely to fail very soon.  I replace *ALL* the caps of a
specific type.  In particular, the caps around the CPU tend to die,
because of the heat and the high ripple current.  Typically, I'll
replace 10 to 15 caps.

Is desoldering these caps straightforward?

It varies.  Some boards are very easy to unsolder.  Others have
smaller holes for the leaded parts and are more difficult.  A vacuum
desoldering station is best.  Use plenty of heat and some liquid flux
so that you don't pull the plated thru hole out with the capacitor. If
you see a copper colored ring around a capacitor lead, you've probably
killed the board.

Any special precautions
re: multi-layered PCB traces?

If you don't have a tip that will heat both leads at the same time, or
don't have 3 arms so that you can use two soldering irons, all is not
lost.  I heat up one lead, and rock the capacitor in the opposite
direction.  After it moves a little, I heat the other lead, and rock
it in the opposite direction.  Don't use brute force or you'll rip out
the plated through holes.  Eventually, it comes out.  

One lead is usually grounded where the large copper area acts as an
effective heat sink.  This lead will be more difficult to unsolder
than the hot lead (usually +).  I use a big, wide (1/4"), hot (850C),
chisel tip.  Plenty of heat, and work fast.  This will take some
practice.  Find an old PCB and practice a little before attacking the
Intel motherboard.

Any special gotchas to keep in mind
when ordering replacement caps from say Mouser?

105C Low-ESR.  Watch the case dimensions and lead spacing.  If it will
fit, try to buy the next higher voltage rating.  I'm partial to
Panasonic but will use Rubycon.  Digikey, Mouser, and eBay (in that
order).  I sometimes use polymer caps as replacements, when the
motherboard is worth fixing and the customer doesn't care about the
cost.  Also, think about buying an ESR tester if you're going to make
a habit of this.

http://www.badcaps.net
http://www.afrotechmods.com/groovy/capacitor_replacement/capacitor_re...
http://en.wikipedia.org/wiki/Capacitor_plague
http://www.capacitorlab.com

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

Ok, thanks to everyone who replied. Seems doable... looks like I'm
going shopping for a vacuum desolderer.

Michael

 

On Mon, 20 Sep 2010 12:52:38 -0700 (PDT), Michael
<mrdarrett@gmail.com> wrote:

Hello,

I've got a couple of Intel boards (D865PERL) that have one bad
electrolytic capacitor each. One board stopped working; the other
still works, but has a bulging cap close to the CPU area. (Pics not
yet available.)

Is desoldering these caps straightforward? Any special precautions
re: multi-layered PCB traces? Any special gotchas to keep in mind
when ordering replacement caps from say Mouser?

Thanks,

Michael

I've done this on motherboards; it's tedious, but practical. The
suggestions from others are good. Here's a few things I discovered.

While vacuum desoldering tools work well, you have to heat the board
to the point where the solder on the ground lead melts all the way
through the board. The vacuum desoldering tools aren't real efficient
at transfereing heat unless you add a little solder or flux to each
lead you are going to unsolder.

The technique I settled on was to use a 40 watt soldering iron with a
chisel tip. Heat up one leg, add a dab of Chip-Quik, rock the cap
toward the opposite side. Heat up the other leg, add Chip-Quik, rock
cap to other side. Repeat with the heating and rocking until the cap
drops out. While it's still hot, push an iron or stanless steel
needle through the hole (I use a dissecting pick I got in the '60's).
Remove the pick when the solder has cooled; reheat the other hole and
use the needle.

Make sure you keep a chart identifying which cap goes where. Patience
is necessary. Make sure you clean up all stray solder.

PlainBill

 

[whit3rd]

On Sep 21, 11:28 am, Michael <mrdarr...@gmail.com> wrote:

Ok, thanks to everyone who replied.  Seems doable... looks like I'm
going shopping for a vacuum desolderer.

For a one-off project, desoldering braid (it sucks up solder like a
sponge)
is almost as good, and doesn't have the sticker-shock effect.

Practice on a scrap board or two FIRST. It's easy to damage
things while the iron is hot and the polymers are soft.

 

[tm]

<PlainBill47@yawho.com> wrote in message
news:4lbi965jd71ul7r54uffsdis8ak4etl90f@4ax.com...

On Mon, 20 Sep 2010 12:52:38 -0700 (PDT), Michael
mrdarrett@gmail.com> wrote:

Hello,

I've got a couple of Intel boards (D865PERL) that have one bad
electrolytic capacitor each. One board stopped working; the other
still works, but has a bulging cap close to the CPU area. (Pics not
yet available.)

Is desoldering these caps straightforward? Any special precautions
re: multi-layered PCB traces? Any special gotchas to keep in mind
when ordering replacement caps from say Mouser?

Thanks,

Michael

I've done this on motherboards; it's tedious, but practical. The
suggestions from others are good. Here's a few things I discovered.

While vacuum desoldering tools work well, you have to heat the board
to the point where the solder on the ground lead melts all the way
through the board. The vacuum desoldering tools aren't real efficient
at transfereing heat unless you add a little solder or flux to each
lead you are going to unsolder.

The technique I settled on was to use a 40 watt soldering iron with a
chisel tip. Heat up one leg, add a dab of Chip-Quik, rock the cap
toward the opposite side. Heat up the other leg, add Chip-Quik, rock
cap to other side. Repeat with the heating and rocking until the cap
drops out. While it's still hot, push an iron or stanless steel
needle through the hole (I use a dissecting pick I got in the '60's).
Remove the pick when the solder has cooled; reheat the other hole and
use the needle.

Make sure you keep a chart identifying which cap goes where. Patience
is necessary. Make sure you clean up all stray solder.

PlainBill

Good advise and also make sure you take note of the polarity.

 

[Jeff Liebermann]

On Tue, 21 Sep 2010 11:28:35 -0700 (PDT), Michael
<mrdarrett@gmail.com> wrote:

Ok, thanks to everyone who replied. Seems doable... looks like I'm
going shopping for a vacuum desolderer.

While a proper vacuum desoldering station is nice, you can get away
with using a solder sucker.
<http://www.amazon.com/SOLDER-SUCKER-DESOLDERING-DESOLDER-REMOVAL/dp/B0002Y8OPM>
It requires some practice at both using and cleaning. I use one when
I'm too lazy to fire up the desoldering station.

Someone suggested using solder braid. I disagree. I've lifted so
many traces and pads from the board with solder braid, that I won't
use it unless I'm depserate.

Don't forget the stainless steel needle or pin for cleaning the hole.
--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
# http://802.11junk.com jeffl@cruzio.com
# http://www.LearnByDestroying.com AE6KS

 

[Jeffrey Angus]

On 9/21/2010 8:51 PM, Jeff Liebermann wrote:

Someone suggested using solder braid. I disagree. I've lifted so
many traces and pads from the board with solder braid, that I won't
use it unless I'm desperate.

About the only thing solder braid is good for is phenolic PC boards
with brass rivets for the through holes.

That and lifting traces.

Jeff (the other other one)

 

[Michael A. Terrell]

Jeffrey Angus wrote:

On 9/21/2010 8:51 PM, Jeff Liebermann wrote:
Someone suggested using solder braid. I disagree. I've lifted so
many traces and pads from the board with solder braid, that I won't
use it unless I'm desperate.

About the only thing solder braid is good for is phenolic PC boards
with brass rivets for the through holes.

That and lifting traces.

And cleaning the solder off the pins of Octal tubes.


--
Politicians should only get paid if the budget is balanced, and there is
enough left over to pay them.

 

[Jeffrey Angus]

On 9/21/2010 11:29 PM, Sergey Kubushyn wrote:

I recently restored and fully recapped two Kenwood KA-9100 amps. All the
boards are phenolic and I used solder braid on them.

And they are not multi layer boards with 0.010" traces.

Jeff

 

[Sergey Kubushyn]

Jeffrey Angus <jangus@suddenlink.net> wrote:

On 9/21/2010 8:51 PM, Jeff Liebermann wrote:
Someone suggested using solder braid. I disagree. I've lifted so
many traces and pads from the board with solder braid, that I won't
use it unless I'm desperate.

About the only thing solder braid is good for is phenolic PC boards
with brass rivets for the through holes.

That and lifting traces.

I recently restored and fully recapped two Kenwood KA-9100 amps. All the
boards are phenolic and I used solder braid on them. Surprisingly they held
very good, not a single lifted trace. I do have all the usual soldering
stuff--hot air, vacuum desoldering station etc.--but braid was the best one
for the job. It even allowed me to remove all the switches and pots for
cleaning (I disassemble all of them and clean all the contacts with silver
cleaner occasionally replating some with new silver coat and replating
severely oxidized hardware with new yellow zinc coat.) It is not an easy
task to do on modern boards because some of those switches have too many
pins... Kudos to Kenwood for using such a good material for their boards...

BTW I do remove all those wire-wrap studs, drill bigger holes, and install
turrets instead. Eyelets installed in those holes where interconnection
wires go.

Those KA-9100 BTW look very very good for their 30+ years age. All solder
joints look like they just came from the factory. If not that horrible
design flaw in phono preamp section that makes them fail I would say it is
an engineering gem and an example how such things should be manufactured.

---
******************************************************************
* KSI@home KOI8 Net < > The impossible we do immediately. *
* Las Vegas NV, USA < > Miracles require 24-hour notice. *
******************************************************************

 

[Michael]

On Sep 21, 4:59 pm, "tm" <the_obamun...@whitehouse.gov> wrote:

PlainBil...@yawho.com> wrote in message

news:4lbi965jd71ul7r54uffsdis8ak4etl90f@4ax.com...



On Mon, 20 Sep 2010 12:52:38 -0700 (PDT), Michael
mrdarr...@gmail.com> wrote:

Hello,

I've got a couple of Intel boards (D865PERL) that have one bad
electrolytic capacitor each.  One board stopped working; the other
still works, but has a bulging cap close to the CPU area.  (Pics not
yet available.)

Is desoldering these caps straightforward?  Any special precautions
re: multi-layered PCB traces?  Any special gotchas to keep in mind
when ordering replacement caps from say Mouser?

Thanks,

Michael

I've done this on motherboards; it's tedious, but practical.  The
suggestions from others are good.  Here's a few things I discovered.

While vacuum desoldering tools work well, you have to heat the board
to the point where the solder on the ground lead melts all the way
through the board.  The vacuum desoldering tools aren't real efficient
at transfereing heat unless you add a little solder or flux to each
lead you are going to unsolder.

The technique I settled on was to use a 40 watt soldering iron with a
chisel tip.  Heat up one leg, add a dab of Chip-Quik, rock the cap
toward the opposite side.  Heat up the other leg, add Chip-Quik, rock
cap to other side.  Repeat with the heating and rocking until the cap
drops out.  While it's still hot, push an iron or stanless steel
needle through the hole (I use a dissecting pick I got in the '60's).
Remove the pick when the solder has cooled; reheat the other hole and
use the needle.

Make sure you keep a chart identifying which cap goes where.  Patience
is necessary.  Make sure you clean up all stray solder.

PlainBill

Good advise and also make sure you take note of the polarity.

Yes... I was having visions of getting the cap out then wondering,
which way is negative... :-D

Thanks y'all

Michael

 

[Sergey Kubushyn]

Jeffrey Angus <jangus@suddenlink.net> wrote:

On 9/21/2010 11:29 PM, Sergey Kubushyn wrote:
I recently restored and fully recapped two Kenwood KA-9100 amps. All the
boards are phenolic and I used solder braid on them.

And they are not multi layer boards with 0.010" traces.

They are not. There is no such thing as _phenolic_ multi layer boards with
0.010" traces.

BTW, solder braid is very useful on _ANY_ board, including multilayer ones
with 0.010" traces. It requires some skills of course but everything does. I
do use it all the time.

It is not the rifle that shoots way off the target, it is the shooter.

---
******************************************************************
* KSI@home KOI8 Net < > The impossible we do immediately. *
* Las Vegas NV, USA < > Miracles require 24-hour notice. *
******************************************************************

 

[larry moe 'n curly]

Michael wrote:

Yes... I was having visions of getting the cap out then wondering,
which way is negative... :-D

Usually there's a circle printed on the board under each electrolytic
capacitor, and the negative side is filled in, but Asus and Asrock
boards are marked the opposite way, so the filled area indicates the
positive lead instead.

There are YouTube videos about soldering and desoldering, and
BadCaps.net has a lot of information and also sells high-quality
caps. I think they also have a YouTube video.

In my novice opinion, a mainboard made with leaded solder needs a 40W
iron to solder it, a 50W iron to desolder it, and lead-free boards
need even more power. But a regular 50W iron can overheat its tip and
turn it blue or oxidize it, which really hurts heat conduction. There
are adjustable power irons for as little as $10, but I've found that
cheap irons don't last long or don't deliver as much heat to the tip
as good irons of the same power rating. BTW if you buy one off Ebay,
check the voltage because many are made only for 220VAC. If you're
going to spend much at all on an iron, consider getting a temperature-
controlled, 70W Goot PX-201, about $50, which should be able to handle
about anything, and Goot is a quality brand. Temperature-controlled
is better than adjustable power. With any iron, a chisel tip, about
2mm - 2.5mm wide, works better than a conical tip, and tips are best
cleaned with curly brass hair or a damp paper towel, not a sponge.

Manual desoldering vacuums work best if you can hold them on one side
of the board and the iron on the other side and see both sides at
once. Vacuum bulbs don't suck nearly as well as spring plungers do,
but the latter can strike and damage board at the moment the spring is
released. Addng a short length of rubber tubing can prevent the
damage.

Copper desoldering braid works if it's the right width (enough to soak
up all the solder from the hole in one try but not more, generally
2-3mm and the iron puts out plenty of heat. Cut off the used portion
immediately after use so it won't absorb heat from the next joint.
Don't pull out a lead unless all of the solder from the hole has been
removed, and test by wiggling the lead side to side. Generally if all
the solder doesn't come out in one try, it's best to fill the hole
with 60/40 or 63/37 solder and start all over.

Chip Quik may be the easiest and safest way to desolder because it
melts at under 150F, but it costs about $1 per inch.

Radio Shack sells an $11 desoldering iron with a vacuum bulb, and
other sources have a similar tool that has a spring-loaded plunger
vacuum instead. The Radio Shack iron doesn't seem to deliver quite
enough heat to the tip for multilayer boards, but people have modified
it with a better vacuum pump or by wrapping heat insulation above the
tip.

 

[Jeff Liebermann]

On Wed, 22 Sep 2010 05:05:19 +0000 (UTC), Sergey Kubushyn
<ksi@koi8.net> wrote:

Jeffrey Angus <jangus@suddenlink.net> wrote:
On 9/21/2010 11:29 PM, Sergey Kubushyn wrote:
I recently restored and fully recapped two Kenwood KA-9100 amps. All the
boards are phenolic and I used solder braid on them.

And they are not multi layer boards with 0.010" traces.

They are not. There is no such thing as _phenolic_ multi layer boards with
0.010" traces.

Not yet. Some experiments in printed semiconductors and 3D circuits
use multilayer boards. However they don't use solder. They're
stapled together. They're also intended to be throw away assemblies,
so I wouldn't worry about repair.

BTW, solder braid is very useful on _ANY_ board, including multilayer ones
with 0.010" traces. It requires some skills of course but everything does. I
do use it all the time.

I've been soldering for about 50 years, so I suspect I'm sufficiently
experienced to have made all the usual mistakes (several times). It's
not the lack of skill. I have no problem using braid on large objects
with small heat sinks. I have nothing but problems using braid on
small objects attached to large heat sinks. I this case, there's a
small leaded capacitor, connected to a rather large copper heat sink
of the power bus inside the PCB. You can see the effect when
unsoldering the capacitor leads. The ungrounded hot lead comes out
easily. The grounded lead is far more difficult. If the capacitors
are near the CPU and on a power bus, then both leads are difficult.
Braid is also quite suitable for unsolder connections where the solder
is easily accessible and exposed to the braid, such as large xformer
pins, terminal strips, wire terminals, some IC sockets, tube sockets,
etc.

Also remember that this is for what appears to be a beginner at
repair. It's easier to explain how to operate a solder sucker than
braid.

I forgot to mention the desoldering bulb, another device that barely
works:
<http://www.amazon.com/Weller-Desoldering-Bulb-Solder-Off/dp/B00011TUZY>
The only good part is that it's great finger exercise (I play piano).

I recently purchased one of the contrivances:
<http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=220664298701>
It's a solder sucker hung on the back end of a hollow soldering iron.
It took a while to discover what was wrong with this idea. The amount
of vacuum generated is dependent on the unsuck to suck ratio of air
volumes. With an ordinary solder sucker, where the tip is close to
the piston, the ratio is rather large, thus offering a good vacuum.
Not so with this contrivance, as the volume of the hollow tube adds to
both volumes and results in much less vacuum. A larger diameter
piston or shorter soldering iron barrel would have made it work
better, but as it stands, the design sucks. 30 watts also seems
underpowered, the tip is too big, and it takes 10 minutes to warm up.
I haven't used it much, but I suspect that it will clog with dross
near the entrance to the solder sucker.

It is not the rifle that shoots way off the target, it is the shooter.

True. However, I would rather use a guided missile (fancy desoldering
station) than to go off plinking at the target (solder braid).

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

 

[Jeff Liebermann]

On Wed, 22 Sep 2010 16:31:39 +0000 (UTC), Meat Plow
<mhywatt@yahoo.com> wrote:

On Wed, 22 Sep 2010 09:23:21 -0700, Jeff Liebermann wrote:

snip

I've been soldering for about 50 years, so I suspect I'm sufficiently
experienced to have made all the usual mistakes (several times). It's
not the lack of skill.

snip

My first "job" in electronics was in the back room of my barber's shop
who had a little hobby business repairing electronics odds and ends. It
was where I learned how to solder. Especially after being told by one of
the barber's friends that I soldered like his grandmother That was in
1971. I was 16.

That was a compliment.

I started with an Ungar wood burner at about 14 years old. The first
lesson I learned is that the power cord of the iron will melt and
short when I place the iron on it. It was downhill from there as my
father taught me to use a large copper gas fired furnace soldering
thing used to make industrial sewing machine attachments. By
comparison, the Ungar seemed easy. After several years of doing
everything wrong, the high skool electric shop teacher introduced me
to flux. Over the years, I learned the basics, like you can hold
solder in your mouth, but don't try it with copper wire. Far too many
Eico, Heathkit, and Knightkit constructions were great practice.

I recently tried to teach a friends 14 year old brat how to solder.
He's hopeless, but dedicated, and will eventually learn.

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