general question: mainboard caps

[Jeff Liebermann]

On Thu, 23 Sep 2010 10:40:39 -0700 (PDT), Bob Villa
<pheeh.zero@gmail.com> wrote:

Thanks to all for your expertise in de-soldering...there is a world of
experience here, and worth much.
I have never had luck with braided wire...but evidently is works for
some. (I never have any luck with super-glue either!)

Super-glue doesn't do very well for desoldering (or soldering) a
printed circuit boards.

--
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 22, 2:12 am, "larry moe 'n curly" <larrymoencu...@my-deja.com>
wrote:

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.

Went shopping... got a plunger for $11 at Fry's. Harbor Freight has a
180W solder gun for $10... remembered pointers here on high power for
Pb-free solder... is the gun a good idea, or too hot?

 

[Bob Villa]

On Sep 24, 6:00 am, Jeff Liebermann <je...@cruzio.com> wrote:

On Thu, 23 Sep 2010 10:40:39 -0700 (PDT), Bob Villa

pheeh.z...@gmail.com> wrote:
Thanks to all for your expertise in de-soldering...there is a world of
experience here, and worth much.
I have never had luck with braided wire...but evidently is works for
some. (I never have any luck with super-glue either!)

Super-glue doesn't do very well for desoldering (or soldering) a
printed circuit boards.  

--
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

This was unrelated and anecdotal. But, thanks again.

 

[Michael]

On Sep 24, 12:45 pm, Bob Villa <pheeh.z...@gmail.com> wrote:

On Sep 24, 6:00 am, Jeff Liebermann <je...@cruzio.com> wrote:



On Thu, 23 Sep 2010 10:40:39 -0700 (PDT), Bob Villa

pheeh.z...@gmail.com> wrote:
Thanks to all for your expertise in de-soldering...there is a world of
experience here, and worth much.
I have never had luck with braided wire...but evidently is works for
some. (I never have any luck with super-glue either!)

Super-glue doesn't do very well for desoldering (or soldering) a
printed circuit boards.  

--
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

This was unrelated and anecdotal. But, thanks again.

On that note, I have had better luck with a pick axe than a
shovel... :-D (when cutting into the side of the backyard slope, not
on circuit boards)

 

[Mike]

In article <l1oi96d6hks2s9p99efb7806j9avu1h2o3@4ax.com>,
Jeff Liebermann <jeffl@cruzio.com> wrote:

While a proper vacuum desoldering station is nice, you can get away
with using a solder sucker.

Also consider using a small length of *non-melting* (e.g. butyl rubber)
sleeve that will push fit over the business end of the sucker, set to
be about 8mm past the end.

Most of the cheap ones have a nylon-ish end that gets melted very easily
and won't make a good vacuum seal against the board.

With a rubbery end, you get a better seal and consequently better
clearance THROUGH the hole, even if you are at a slight angle to
the board. No good having a vacuum that escapes along the face of the
board.

It also saves the plastic nozzle getting sozzled!

--
--------------------------------------+------------------------------------
Mike Brown: mjb[-at-]signal11.org.uk | http://www.signal11.org.uk

 

[Bob Villa]

On Sep 24, 2:45 pm, Bob Villa <pheeh.z...@gmail.com> wrote:

On Sep 24, 6:00 am, Jeff Liebermann <je...@cruzio.com> wrote:



On Thu, 23 Sep 2010 10:40:39 -0700 (PDT), Bob Villa

pheeh.z...@gmail.com> wrote:
Thanks to all for your expertise in de-soldering...there is a world of
experience here, and worth much.
I have never had luck with braided wire...but evidently is works for
some. (I never have any luck with super-glue either!)

Super-glue doesn't do very well for desoldering (or soldering) a
printed circuit boards.  

--
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

This was unrelated and anecdotal. But, thanks again.

Well, actually, it is related...many ppl seem to be able to get
satisfactory results using braid to de-solder and getting super glue
to stick to the proper thing. (note: not necessarily the same ppl or
at the same time) I do not.
HTMS

 

[Jeff Liebermann]

On Fri, 24 Sep 2010 15:58:11 -0700 (PDT), Bob Villa
<pheeh.zero@gmail.com> wrote:

Well, actually, it is related...many ppl seem to be able to get
satisfactory results using braid to de-solder and getting super glue
to stick to the proper thing. (note: not necessarily the same ppl or
at the same time) I do not.

The trick is to use the braid for desoldering and the super glue for
adhesive purposes, and not get them mixed.

Try some epoxy made for plastics:
<http://www.loctiteproducts.com/p/13/7/epxy_plstc_s/overview/Loctite-Epoxy-Plastic-Bonder.htm>

As with all adhesives, the tricks are:
1. Make sure the adhesive is compatible. If the part flexes, you
don't want a really brittle adhesive. If it's porous, you want
something that has plenty of filler.
2. Clean the parts with whatever solvent you find useful. Make sure
it evaporates completely and there's no water residue (such as what
you'll get with alcohol) on the parts.
3. Use as thin a layer of glue as possible.
4. Use clamping pressure and let everything harden per instructions.

--
# 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

 

[Jeff Liebermann]

On Fri, 24 Sep 2010 12:44:12 -0700 (PDT), Michael
<mrdarrett@gmail.com> wrote:

Went shopping... got a plunger for $11 at Fry's. Harbor Freight has a
180W solder gun for $10... remembered pointers here on high power for
Pb-free solder... is the gun a good idea, or too hot?

This one? 1135F is far too hot:
<http://www.harborfreight.com/welding/soldering/180-watt-industrial-soldering-gun-4328.html>
Take it back or give it to your worst enemy. It's totally unsuitable
for soldering printed circuit boards. You need a temperature
controlled iron, with replaceable tips (for different types of work).
--
# 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

 

[Michael]

On Sep 24, 6:35 pm, Jeff Liebermann <je...@cruzio.com> wrote:

On Fri, 24 Sep 2010 12:44:12 -0700 (PDT), Michael

mrdarr...@gmail.com> wrote:
Went shopping... got a plunger for $11 at Fry's.  Harbor Freight has a
180W solder gun for $10... remembered pointers here on high power for
Pb-free solder... is the gun a good idea, or too hot?

This one?  1135F is far too hot:
http://www.harborfreight.com/welding/soldering/180-watt-industrial-so...
Take it back or give it to your worst enemy.  It's totally unsuitable
for soldering printed circuit boards.  You need a temperature
controlled iron, with replaceable tips (for different types of work).
--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
#http://802.11junk.com              je...@cruzio.com
#http://www.LearnByDestroying.com              AE6KS

Ok thanks. Didn't buy it... decided to shop around a bit first.
Thought if it is too high a power, just shut of power immediately once
the solder melts... but ok, good idea, I'll pass on this.

 

[Daniel Mandic]

Michael wrote:

Went shopping... got a plunger for $11 at Fry's. Harbor Freight has a
180W solder gun for $10... remembered pointers here on high power for
Pb-free solder... is the gun a good idea, or too hot?

Calculate with ~70-120$. The brand I leave to you...

40-60W, analog- or digital controlled with variation knob, tip-holder
and sponge-drawer.
Solder stations are not that expensive, indeed!

e.g.
http://www.ersa.com/art-0ana60-358-1910.html

mine

or
http://www.soldering-shop.co.uk/catalog/48w-soldering-station-p-503.html

and
http://www.soldering-shop.co.uk/catalog/weller-whs40lt-soldering-station
-special-edition-p-49.html

and so many more...


Cheap things are not worth the money.


--
Daniel Mandic

 

[Bob Villa]

On Sep 24, 8:27 pm, Jeff Liebermann <je...@cruzio.com> wrote:

The trick is to use the braid for desoldering and the super glue for
adhesive purposes, and not get them mixed
..

You must mix epoxies! (Your trying to make me out to be an idiot,
after I was saying "Thanks")

Try some epoxy made for plastics:
http://www.loctiteproducts.com/p/13/7/epxy_plstc_s/overview/Loctite-E...

As with all adhesives, the tricks are:
1.  Make sure the adhesive is compatible.  If the part flexes, you
don't want a really brittle adhesive.  If it's porous, you want
something that has plenty of filler.
2.  Clean the parts with whatever solvent you find useful.  Make sure
it evaporates completely and there's no water residue (such as what
you'll get with alcohol) on the parts.
3.  Use as thin a layer of glue as possible.
4.  Use clamping pressure and let everything harden per instructions.

I was only speaking of SuperGlue (Cyanoacrylate). I follow the
directions for SG...but it doesn't co-operate. My favorites are epoxy
and silicone glue. (and I don't use either for soldering!)

 

[Jeff Liebermann]

On Sat, 25 Sep 2010 05:34:30 -0700 (PDT), Bob Villa
<pheeh.zero@gmail.com> wrote:

On Sep 24, 8:27 pm, Jeff Liebermann <je...@cruzio.com> wrote:

The trick is to use the braid for desoldering and the super glue for
adhesive purposes, and not get them mixed
.
You must mix epoxies! (Your trying to make me out to be an idiot,
after I was saying "Thanks")

Nope. Just having fun twisting your words. I do that when I'm bored,
half asleep, lazy, or there's nothing worth watching on TV. Your
original comment:
I have never had luck with braided wire...but evidently is
works for some. (I never have any luck with super-glue either!)
hints that you're using super-glue for desoldering. I would
appologize, but I've consumed my daily ration of appologies today, so
you'll have to wait until tomorrow.

Try some epoxy made for plastics:
http://www.loctiteproducts.com/p/13/7/epxy_plstc_s/overview/Loctite-E...

I was only speaking of SuperGlue (Cyanoacrylate). I follow the
directions for SG...but it doesn't co-operate. My favorites are epoxy
and silicone glue. (and I don't use either for soldering!)

Superglue doesn't bond well with many plastics and porous materials.
However, that's only part of the problem. The real problem is that
many materials are fairly flexible. Superglue is hard as a rock, and
will crack if the bond line is too thick. This limits its
applications to gluing things that fit together quite close. There
are some cynoacrylate adhesives (i.e. gel type) that claim to have
some filler, but I've never found that much of an improvement. Like
you, I've had dismal luck with superglue. Try the epoxy I suggested.
--
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 Fri, 24 Sep 2010 23:31:42 -0700 (PDT), Michael
<mrdarrett@gmail.com> wrote:

Ok thanks. Didn't buy it... decided to shop around a bit first.
Thought if it is too high a power, just shut of power immediately once
the solder melts... but ok, good idea, I'll pass on this.

I use a Weller TC201 soldering station. That's not because I like it
but because I once picked up a large collection of these from a
surplus sale that should keep me well stocked with parts and pieces
for the rest of my life. I wouldn't recommend this model because of
the rather marginal mechanical thermostat and the rather high price of
the current models. I have to clean the contacts on mine about once a
year.
<http://www.mcmelectronics.com/product/WELLER-WTCPT-/96-030>

There are cheapo temperature controlled soldering stations on eBay for
$30 and up.
<http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=200522416320>
<http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=280565323462>
Make sure you can buy replacement tips, replacement parts, and that
you can control the temperature of the tip. Also, that it's somewhere
between 50 and 90 watts. You can probably get away with 40 watts, but
not for soldering or desoldering anything big (such as big terminal
lugs and cables). My Weller TC201 is 60 watts, which is sometimes
inadequate.

If you have money, there's the Weller WD1002 for about $300.
<http://www.testequipmentdepot.com/weller/solder/wd1000.htm>
Oh yes, you'll need a few different size irons, soldering pencils,
tips, and accessories:
<http://www.testequipmentdepot.com/weller/pdf/wd1002.pdf>
Have your credit card and loan officer ready.


--
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