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How to remove solder from plated-through holes?

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I do this all the time. Have you tried to add some solder to the wick as your doing it? You cant do it dry all the time.
Adam

Hi, Everyone, opposite question with Adam

I bought Litz wire from a company, but I do not know how to soldering it.
http://www.rmcybernetics.com/shop/wire-and-cable/litz-wire

I do not know how to do it? The company does offer soldering for me for 2 pounds each side, but I want to learn and DIY. Can you do some help please?
 
Sires . . . . . . .

Soldering pot . . . SOLDERING POT ? . . . . . what is a a soldering pot ?
Oh, yes, now I remember, that's the DRAKE unit that I gradually stopped using, about 1956.

Ye olde tyme DRAKE " solder crock pot " . . .circa 1948

upload_2016-10-29_4-14-15.png


Wire gauge and components became smaller, less wiring required tinning and those new fangled printed circuit boards started appearing.
In the early days of circuit boards I made sure that all my components leads and wires were WELL solder / tin wetted.
Rather than pulling out that BIG old power hungry unit, in about 1966 I made a variant, that since, has well served my needs.
It is the bottom unit of the two below, it was constructed from a slab of Amerikanski Oak wood.
It's dimensioned at 2.2 cm thickness . . . 9 cm long and 4cm high.
The very top was divided into 1/3's and an initial prick drilling with a 2 mm drill bit made 2 holes. That would then hold the drill tip such that it could then be tilted to slope drill the 2 holes so that they intersected and met about 2.5 cm down.
That then establishes a good drill path, such that a larger 7.5 mm drill bit enlarges those initial pilot holes.
8 time separated coats of marine spar varnish completed the unit . . . .that was the best coating at that timeframe.
Still . . . . . .lookin' good . . . . . . after 60 years of service.
But it has received a break, since about the 80's . It only get's pulled out whenever I misplace the new one for a time.

"Road kill" from a neighbors curbside castoff yielded a solid hard rock maple table top.
The new units construction expanded its length to 10 cm and 4 cm wide and a clamped gluing of two 2.2 pieces resulted in the almost same 4.4 cm height.
The new sloped drill holes are now 1.25 cm. This new unit received about 10 coats of Varathane poly.
My only change, if building another unit , would be to cap off the units very top with an anodized aluminum plate .
Those plate edges are draw / mill filed to a chamfer . . . making a perfect fit to the wooden top.
4 brass brads slightly inset from the 4 corners, inserted into pre drilled, slightly undersize holes, then with the brass brads driven home.

HOWITWORKS

My big unit serves both for a solder tinning pot and a soldering iron tip tinner.
The special sloped shape on one end of these units serve for the fingers and thumb to be able to hold the unit down, well clear of a hot area.
If your iron tip needs tinning, you start it's warm up and start scraping it against the solder blob in the unit.
As soldering iron temperature ncreases, some metal transfer will be initiated as well as some oxide will be scraped off from the yet quasi solid surfaces.
When you start seeing the very initial onset of a molten state of the solder blob, place 5 or so drops of rosin flux *** atop the solder blob.
Continue scraping and rotating the tip and you should end up with a tinned tip, sitting down within a molten solder blob.

I use a 50-60 watt iron . . . . .and after having bought a lower wattage iron back in the dark ages, NEVER will I have less than a 50-60 watt unit.
You can ALWAYS decrease voltage with a series silicon diode in the worse case; or use a lamp dimmer to trim into exactly the temperature that you want.
Small soldering tips can be custom made for cramped quarters or small work .
PLUS the axiom when using higher temp is get in and get the job done in a hurry . . . .because it has no heat hesitation and will do it in a hurry . . . . and then move the iron away.

If you want to progress to the solder pot function, dip the tip down ever deeper and also start working on the other adjunct solder blobs cavity.
It shouldn't be too long until both blobs are molten.
That's when your iron tip is left at the rear large end and the frontal hole is where you do dip tinning.
Grab that scraped / cleaned item which is to be solder tinned and dip it in rosin flux.
Then you dip it down into the frontal molten solder blob, to then take on tinning and then rapidly lift up and out . in order .to avoid an end solder spike.
If I have MANY tinnings to be done, I have a lamp with a 1/2 cm back riser, i just position the two and use an Acco clip to hold the soldering iron cord to the riser and the adjusted dangle of the soldering iron, then lets its tip rest down within the rear solder blob.

Cheeep materiel:

Certainly one has seen forklifts hustling heavily laden wooden loading pallets. Their fabrication justifies a hardwood being used, due to the heavy weight being subjected to them.
The heavy "2 X 4 " cross bars typically will be rough hewn oak, sometimes, even hickory or ash . . . .or with hardy poplar being the worse case.
Put an orbital sander to a piece and you will see the rapid enhancement of its appearance.

rosin flux ***
The last I had to buy was way back in 1982.
Having 2 majestic 75 ft + pine trees in the front yard, I have been harvesting my rosin from them. That involves drilling about 16 upward sloping 3/32 in holes spaced about each tree, lightly tap toothpicks into each hole, wait 2 months and then harvest blobs of rosin.#
Dissolve with denatured alcohol, thinning to the desired viscosity.
If Kester 44 "activated" rosin flux is desired . . . . warm the flux mix in its 1oz glass container . . . by nestling it within a hot water bath . . .add 5 drops of hydrochloric acid, shake well.

# Later, I had to place the holes facing away from street side view, due to kids and neighbors a sayin' "What ? the ? hey ? " and sometimes they pre harvested a few of them.


YE OLDE TYME WOODEN SOLDER POTS :

kgCAMRz.jpg



73's de Edd
 
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I have a double-sided pcb with plated-through holes occupied by component legs. I removed a dead 16-pin DIL IC by chopping off its legs, then unsoldered the legs individually. Use of a solder sucker and solder wick has failed to clear the vacated holes. Any suggestions how to clear them so that I can insert a new IC? (I don't have an iron with the tip shape or heat capacity to solder 8 legs at a time, and I'm reluctant to drill out the solder).

after you heat up the solder, you also can use a needle sharp pencil (graphit) to keep the hole open, that should work too one by one and it is cheap :)
 
You could try using a sewing needle to poke through the hole as you heat the solder up....I have had to resort to that before I bought a vacuum assisted de-soldering unit.....and make sure the iron has enough wattage to heat up the hole....
 

CDRIVE

Hauling 10' pipe on a Trek Shift3
This thread makes me chuckle. For more years than most of our members have been alive I've used a hot iron and rapped the board on the bench. The plugged hole clears easily with the solder flying out and splattering on the bench. Through hole or not! I usually add more solder first so the iron can heat it fast.

IMHO low power irons do far more damage to a board than a really HOT one because the latter can get on and off the pad much faster.

Chris
 
7. There is another "dumb way" to clear holes:
Use a round needle-like tool, made of a material the solder "doesn't stick to" , like steel.
Heat the solder and insert the needle while constantly moving the needle ,it may work.

I was going to suggest this as well after having read about desoldering with hollow needles, apparently being an efficient method. Costing only around US$ 2 for a set I figured it's worth a shot. Search for "hollow desoldering needle tool". Does anyone else have experience with these?
 
Try using a hyperdermic syringe needle to suck up the solder as you are sofening it.

The melted solder can go up from the pointed end. You may need to try different gauge needles.
They are generally made of stainless steel so the solder will not adhere to them.
 
Thanks. I'll bear all the suggestions in mind for next time I have to clear plated-through holes. In the meantime I cheated and soldered some wire stubs into the holes then attached a new IC to the stubs :D.
 
A somewhat crude technique I have used with success is to be ready with the ciruit board VERY close to your face. Heat the hole then quickly blow as close to a exploslve blast as you can manage , forcing the molten solder out. Might take more than one try. DO NOT LEAVE THE IRON IN CONTACT WITH TRACES(S) / FOIL SO LONG AS TO DELAMINATE IT.
 

CDRIVE

Hauling 10' pipe on a Trek Shift3
Mike, you must be a big fan of Hemingway, especially his last short story titled "I Wonder If This Gun Is Loaded"?

Chris
 
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