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De-Soldering Questions

Prysmatyk said:
Being new to electronic repair I never expected the underside of the boards to have thick rivers of solder covering large areas of components. After reading about this and asking AI about the whjy it is there, I learned this 'glob' of solder was used to isolate 'like' components and ensure the soldered pieces stayed put.
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I think you are seeing the results of something called "wave soldering".

That was a method used for soldering thru-hole circuit boards on a large scale. This is why you sometimes still hear solder side and component side of a circuit board.

The circuit board is placed in a sort of conveyor belt that allows the bottom of the board to be exposed. The board is then dragged over a vat of molten solder. But the vat is being vibrated so that you actually get standing waves in the molten solder. It is the crests of the waves that contact the bottom of the circuit board and the solder is attracted to the various traces and pads that were not covered with solder-resist.
Not the neatest or prettiest but lots of thru-put.
 
billyz said:
You should not have to remove all of the solder . Just enough to remove the component.
Also, You might want a desoldering tool , like the Hakko fr-301 .
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a57b72bb-4014-445c-a1f1-9bbd0a83e266.jpg

I have an old Hakko 808. Very reliable. You need to clean out the tip occasionally using the spring-like device at the bottom right.
 
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Prysmatyk said:
So I should bite the proverbial bullet and spend the 300 for the tool... well now, I see this hobby is FUNDS and games. lol

Of course, I am not opposed to borrowing one from someone... jk
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I have seen them for under $200. If you get the Japanese version it is even less and there is a simple conversion to make it work better at 120vac.
 
I think that temperature control while desoldering is important. You want the soldering iron hot enough to melt the solder, but not so hot that it burns traces. Mine is set just right. And I have only ever had to use the braid. But I don't do a whole lot of soldering either. Just a project here and there with my cheap Chinese soldering iron that seems to always get the job done...

Next project is finishing off the recap of some speaker crossovers. Really need to get motivated to finish that project. LOL.
 
The desoldering braid is (for me) far easier than using a hand-operated solder sucker, which I never mastered and have permanently abandoned. If I was replacing parts on the board you showed, I think I'd just remove the component itself using braid, solder in the new one, and maybe reflow a little or add some solder to tidy up. Trying to get all that solder off the underside looks like more trouble than it's worth and doesn't seem necessary.

Ultimately all you need is a nice clean solder connection at the hole/component terminal to secure the part to the board and provide conductivity with the trace, which should of course be unbroken all the way to the next part in each direction (and not have lifted).
 
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Prysmatyk said:
Output board showing the river of solder.

Once I remove the solder, I will assume I must replace the solder like it was in the pic. This is where the anxiety rears its head. I know I can accomplish this but before anything I need to know I have the proper way to do so.
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I suspect that back in the day (just realized I still see new equipment done this way) "rivers of solder" was a way to increase power handling of a given trace.

So you may want to restore those "rivers" to approximately their original form.
 
I'm sure a soldering station is handy, but I wouldn't consider them indispensable for someone still getting started or people who don't have to solder on, say, a weekly basis.

There's the cost plus the question of which ones are good, or in some manner lacking.

I've recapped entire components, done a few repairs, and built all my kits (which include a preamp, several phono amps, and a headphone amp) without ever concluding I needed a soldering station. What did happen instead was learning as I went about other items, some of them inexpensive and unassuming, that can make soldering jobs go a whole lot better. These included tools, lighting, magnification, board holders, etc. Overall, I think those contributed more to the work I was doing than a soldering station would have, though I keep telling myself I'll get one for my next kit project...and somehow never get around to it.

I would suggest though, that you get more than one type of tip for your soldering iron, and experiment to find which works best for you. My preference these days is for chisel tips, they seem much faster and more effective than points for almost all the work I do, but that could just be me.
 
Things that are useful for soldering. Tip tinner. Brass soldering iron tip cleaner. Flux pen. That cheap soldering iron rest where you put the iron when not using it. Decent solder. Braid in two different widths.

As I said, I use a cheap Chinese soldering iron that has worked quite well for me for all my projects (I don't do that many). Before I had a Radio Shack one and the Chinese one easily outperforms that. It comes with different tips as well. I have just been using a pointy tip. Temperature is set. I don't know how accurate the temp reading is on it but right now I only have to hold it there for a second and the solder melts quite easily. I never adjust the temp. Set it and forget it.

A lot of times I wear reading glasses when soldering so I can see things better. I also have one of those small "helping hand" things when I need to clamp something in place so that it does not move. The other day my son was the helping hand when I had to desolder a few bulbs on a small board.

Your results may vary...
 
Tom A. said:
Look up Soldapullt.
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There's a million copies out there now (I guess its way out of patents if it ever was) and many are not just cheaper, they are better. Goot (Japan) make one and it blows the original out of the water IMO. And plenty of Chinese $5-10 copies are excellent.

There's even Chinese copies of the Japanese Goot copy. LOL.

They pull a lot of solder and quickly. Desoldering stations are great when you're feeling lazy, but you'll be spending time cleaning, unblocking and replacing parts (filters) and waiting for them to heat up. My Hakko actually is being retired from my bench as I rarely use it these days, even though it cost me a fortune back in the day.

Suckers, braid and vac desoldering stations all have their place, but an inexpensive, good sucker or two and some braid to clean up is really the best place to start.
 
I should say my comment was only concerning soldering stations vs. soldering irons. I may have misunderstood OP when he said "station". My error. So I wasn't talking about desoldering/rework stations or desoldering guns. Sorry if that looked confusing.
 
Tonoje said:
I'm sure a soldering station is handy, but I wouldn't consider them indispensable for someone still getting started or people who don't have to solder on, say, a weekly basis.
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The temp control is important.

For me, it is also critical that the chassis or boards are well supported. They must not move and be under good lighting to do a quality solder job. I like using an Optivisor. Lighted ones are nice.

chassis and solder.jpg

vise - small jewelers.jpg
Small PanaVise vise for boards.

OptiVISOR1_Left2_Small.jpg
Optivisor.

optivosor- LIGHTed.jpg
Lighted Optivisor. I don't own one of these.
 
I have a number of stations but all of them have a built-in vacuum station with gun. Adjustable heat for both the soldering tip and the suction gun. to remove solder just use the desoldering gun, heat the solder up till liquid, and pull the trigger, it will start sucking up any solder that is liquid.

This is my cheap on, I have another one at the house and it is a much better one, but more expensive as well. This one works just fine, but keep the tip poked out making sure no cold solder gets plugged up in there.


WIN_20260403_07_19_40_Pro.jpg
 
Ken Boyd said:
This one works just fine, but keep the tip poked out making sure no cold solder gets plugged up in there.
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The best advice I ever took in, in relation to temperature controlled de-soldering stations, was de-solder horizontally* AND keep the suction on for 2 seconds after the joint is sucked off. Makes all the difference and it's rare (but not unheard of), that you need to remove/stab/drill-out the blocked solder blob in the iron core...

*that means the board (PCB) is vertically oriented.
 
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The vacuum desolderers are much superior to braid or Soldapullts or bulb suckers and the cheaper ones on Amazon work just as well as the expensive Hakko units.

EDIT: OK, technically, all "sucker" type desolderers are vacuum but I mean the ones in a unit with a motor-driven vacuum and the little "gun" and you pull a trigger to vacuum the solder away.

Doug
 
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