OT:soldering ?
Mikey
board completly so I can get at the bottom of it. It is apparent that
removing the socket will be the hard part of this job.Does anyone have any
pointers to share before I take this on.What is a good way to wick up solder
once it melts(obviously you don't want to drop any when removing the slot).
Thanks guys
Mikey
DiskDoctor
a solder sucker both together but eather should do. seems like most
slots in irds are a tight fit even without the solder so take your
time removing the solder from the holes. if you run into any that
wonte get all the solder out,,, resolder it then try again. do not
keep heat in any one place for extended periods of time when trying to
remove the solder.
your best bet is to find something dead and practice on it first, like
an old modem, you dont want to " learn " on the reciever.
On Mon, 16 Sep 2002 11:54:06 -0400, "Mikey" <mi...@hatespam.mnsi.net>
wrote:
Warning windows has detected mouse movement. Your computer will now reboot.
TheBigFire
Sucker" not actual name but pretty descriptive. It is a soldering iron with
a vacuum bulb attached. Real simple and clean.
"Mikey" <mi...@hatespam.mnsi.net> wrote in message
news:am4uq...@enews2.newsguy.com...
TheBigFire
"PlainBill" <Plain...@yahoo.com> wrote in message
news:skbeou8e3k0vpgj90...@4ax.com...
> Use Chip-Quik. It's a low melt alloy that will reduce the melting
> point of the solder to the point it can be easily removed with a
> solder sucker or solder wick.
>
> PlainBill
>
> On Mon, 16 Sep 2002 11:54:06 -0400, "Mikey" <mi...@hatespam.mnsi.net>
> wrote:
>
EEng
prevent errors and damage. Not just any soldering iron will do when
the traces and pads are small however on average including for
traces/pads down to .010" (called a 10x10 layout) the best iron is a
Weller WTCPT 42Watt using a PTA7 needle tip or a PTA8 chisel tip
(comes with a PTA8 already) which provides 700 and 800 degrees
respectively. While this may seem high temp to the novice, those with
experience will tell you that shorter hotter desoldering times work
better than lower temperature but longer reheat times.
Lower temperature irons will cause you to leave the tip in contact
longer. Longer heating time means higher likelihood of lifting a pad
due to melting the bonding substrate that clads the copper to the
phenolic or FR4 circuit board material. The bonding is designed to
melt over time, not over temperature, thus shorter times, albeit
hotter, work best provided the correct technique is employed. Here at
PTS we teach our employees to pass Weapons Grade soldering spec
(highest soldering spec there is) using these same tools on boards as
tight as 8x8. Special tools are required for smaller traces and pads.
Shorter hotter contact (to a point) will melt solder quicker and
eliminate lifted pads Presumably, the solder in question is SN63/37
Ultrapure or Ultra Low Dross (industry standard).
Always tin and wet the iron first. This means, melt solder onto the
tip and allow it to sit and smoke for a few moments. Rotate the iron
to get the solder all over the tip.
Wipe off the excessive solder on a damp sponge. Your iron tip should
now be shiny silver and free of solder.
Now add just a tiny TINY amount of solder to the tip just to " prime"
it. This is called Whetting and will improve thermal conductivity.
When soldering, place the tip whetted face first, so that it comes in
contact with both the lead and the pad at the same time. Solder must
anneal properly to the both lead and pad or you get a cold solder
joint (has resistance) which can cause troubleshooting nightmares.
Now apply solder to the lead and pad junction on the OPPOSITE side of
the lead from the tip. Most people apply it to the tip side, but that
will lead to uneven soldering. The heat transfer to the lead and pad
must draw the solder around the lead to ensure proper capillary feed
of the solder through the pad hole.
Once the solder begins to flow, watch for it to " bubble" as it sucks
through the hole. Once this is done, remove the tip from the lead by
drawing it UP the length of the lead, not by merely pulling it away.
Proper technique will create a solder joint that is shiny (dull
indicates a cold solder joint) and looks like a pyramid going up the
lead, but with concaved sides.
Desoldering is even more critical because the lead/pad have already
been heated once before. Obviously the less times its heated the
better off it is, but desoldering happens.
Solder suckers require more heat, more time and often leave solder
dust on the board that can cause fine trace shorts. Desoldering wick
works faster and at lower heat but takes some skill to use. 10
minutes practicing will teach you what you need to know to use wick.
Remember that being the second or third time the pad has been heated,
both short time and low heat are desired.
Use a rosin based wick to help the solder flow. Standard rosin core
is fine, but if you can get it, Water Soluble Organic Flux based wick
works best and leaves little residue. Military No-Clean solder may
SEEM like a perfect solution, but the small clear residue it does
leave is highly caustic and over time (3-5yrs) will eat away at the
traces and pads. In high voltage applications, this time decreases to
months.
Its important to note that in most cases, adding just a tiny amount of
solder to the area being cleared will improve thermal conductivity ...
whetting the site, just like whetting the iron.
Cut the desoldering wick/braid at a sharp angle to produce a fine
point. Place this point directly on the area being desoldered and
place a whetted tip on the braid.
A few seconds later you will see solder wicking up the braid (you want
this). The real trick here is knowing when all the solder is gone or
when you should cut off the saturated braid and do it again.
Obviously you want to get it all in one shot if you can but that's not
always practical. Remember you have both heat and time against you.
Less time is better.
When the solder wicks up the braid, you'll notice the braid changes
color from copper, to gold, to silver. The copper is its natural
color. The gold is the flux leading the solder up the braid. The
silver is of course, the solder.
NOTE: HERE IS WHERE YOU MAKE OR BREAK DESOLDERING WITH WICK.
Watch the gold coloring move up the braid. Watch the silver coloring
doing the same. When the silver color stops wicking, watch the gold
to see that it continues. It should continue for only a few seconds
longer. THAT is the time to remove the wick and see a clean hole. If
there is still solder there, repeat the process.
There may come a point where no amount of wick will work. We allow
our employees to reflow the pad only once and try again. After that,
a desoldering iron with continuous suction is used, but that's a tool
you're not likely to have access to. If it comes to that, get a
solder sucker from Radio Shack and really inspect the board using a
magnifying glass to make sure there's no fine solder dust left on the
board.
I know its a lot of info, yes I'm verbose, but PTS maintains an annual
rejection rate of 0.75% when the industry average is 5% and the
military average is 2%.
EEng
On Wed, 18 Sep 2002 08:46:31 -0400, PlainBill <Plain...@yahoo.com>
wrote:
>DigiKey (www.digikey.com); MCM Electronics (www.mcmelectronics.com);
>local electronics parts distributors.
>
>PlainBill
larmo
email address. Your email address is the only thing I don't have.
On Wed, 18 Sep 2002 11:56:38 -0700, EEng <unmai...@budget.net>
喊`昂,,,,喊`昂,,,,喊`昂,,,,喊`昂
"Computers don't make errors.
What they do they do on purpose."
Dale - from King of the Hill
喊`昂,,,,喊`昂,,,,喊`昂,,,,喊`昂
Larmo's Bargains is at http://larmosbargains.com
-------
Hobby stuff :-)
http://www.dssftp.com
The FTP site is ftp://larmo.d2g.com
And for good reading, go here also.
http://members.shaw.ca/kb57/new/
TheBigFire
"PlainBill" <Plain...@yahoo.com> wrote in message
news:b5hjou4b3adu51mej...@4ax.com...
> It may have escaped your attention, but we aren't discussing the
> repair of a mil spec piece of ultra compact electronics by an
> experienced tech. We're discussing removing a smart card socket, for
> pete's sake!!! Solder wick works fairly well IF you can heat all pins
> of the part well enough to melt the solder completely. This is very
> difficult when you are dealing with a board with a heavy ground plane,
> and relatively heavy leads on the part.
>
> Chip-Quik is particularly useful for the amateur because it melts at
> a very low temperature, thus reducing the chances of lifting any pads.
> In the case of a card slot, Mikey should be able to easily melt the
> solder on all pins on one side of the socket AT THE SAME TIME,
> allowing him to lift that side of the socket without any risk of
> damaging the board.
>
> PlainBill
>
> On Wed, 18 Sep 2002 11:56:38 -0700, EEng <unmai...@budget.net>
EEng
wrote:
>It may have escaped your attention, but we aren't discussing the
>repair of a mil spec piece of ultra compact electronics by an
>experienced tech. We're discussing removing a smart card socket, for
>pete's sake!!! Solder wick works fairly well IF you can heat all pins
>of the part well enough to melt the solder completely. This is very
>difficult when you are dealing with a board with a heavy ground plane,
>and relatively heavy leads on the part.
NOT if you know the correct technique for doing so which you have made
very clear you're not at all interested in knowing and would prefer
nobody else know too. Then by all means ignore this lesson in correct
soldering/desoldering technique altogether. God forbid someone should
learn anything. What's important is they agree with you alone, right?
To the original poster, next time you ask a question, please insist on
the easiest way of doing things rather than the correct way. Mr.
Bill's ego has decided that you must not learn anything if he doesn't
approve it first. There are many correct ways to do most jobs, this
is the correct way to desolder using wick, which is what you asked
about. I hope you found some useful info there, but make sure to get
PBs approval first!
>
> Chip-Quik is particularly useful for the amateur because it melts at
>a very low temperature, thus reducing the chances of lifting any pads.
>In the case of a card slot, Mikey should be able to easily melt the
>solder on all pins on one side of the socket AT THE SAME TIME,
>allowing him to lift that side of the socket without any risk of
>damaging the board.
>
>PlainBill
>
>On Wed, 18 Sep 2002 11:56:38 -0700, EEng <unmai...@budget.net>
>wrote:
>