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Do I need better soldering iron for non-Leaded solder?

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lordvader88:
I'm trying to de-solder the output caps of a computer PSU. I'm having a hard time de-soldering non-leaded solder. I'm using flux, I keep adding 60/40 solder to dilute the factory stuff, trying to use a pump, and using solder wick. And it's taking a lot longer than I bet it should. The traces are big I guess but still.

I'm using a cheapo $40 solder station w/ temp control I think it was 40W but IDR. It supposedly goes up to 450C. And I'm putting the dail over 400C, almost max. And in no time the tip gets oxidized, so I'm always trying to clean it, dip it in flux, and tinning it.

I swear it took me 20min to remove 3 caps (made a bit harder since it was hard to grasp them)

coppercone2:
throw flux on the joint to desolder and soak the solder braid in flux and use the yellow nasty sticky flux rather then the clear low residue one. You need stronger shit for old non leaded joints. Also you can put solder on your braid then press the braid against the joint then the solder iron against the braid to start the wicking process.

Doing this may help. You can put a big glob of solder down. Your tip should not oxidize that fast though.

I recommend you melt a big glob of solder on top, melt the whole joint, and use a solder sucker though. If its being a bitch you can melt it and use a duster-spray/compressed air in a tiny nozzel like the straw to blow the solder inwards, but you get little spikes of solder that go all over the place. With really big caps you can yank on them a bit with no consequence they seem to be built pretty tough, I have seen them shot out of black powder guns before lol. You can like melt one joint, pull on it a tiny bit to move it up, then do it on the other joint, and kinda walk it out. When its almost walked out you add more solder to actually fill the joint so you have thermal transfer and you keep walking it. In the end you might get a tiny little connection that you can just rip off,

basically the strength of electrical solder tensile is roughly 6000 pounds per square inch.

So if you have
6000=640mm2
x=0.1mm

so a little 0.1mm bond has a tensile strength of less then 1 pound. I would not worry too much about ripping it a bit when its almost done and you have some pissant contact between the capacitor and a VIA for instance (fucking super annoying).

lordvader88:
Yeah I'm using a jar of flux thats like thick honey. I dip the solder wick in there with heat.

I'm going to try some more today. I took a lot of stuff off another PSU and that took forever too. If it was anything truly temperature sensitive I would have fried it for sure.

I'm using a chisel tip and a more rounded 1. And I'm cutting off lengths of the wick, so I'm not heating the whole thing.

coppercone2:
melt the whole thing and use a sucker or walk em out or try blowing in there with strong compressed air when molten but be sure to expect that little globs of solder will fly on things and possibly short out your circuit and be annoying/sharp.

wick freaking sucks ass for through hole parts that use a VIA anyway. IMO its a SMD thing or for cleaning solder attachment points etc.

If its a single sided connection on the bottom of the PCB with no VIA then the wick is decent, If its top soldered under the part the wick is less useful and with heavy copper via's wick is just pretty horrible (my extent is 90W irons from hakko/weller)

lordvader88:
Ok I'll try more solder. This is just 1-sided PCB, thankfully no solder on the top.


I have a brand new tip here I can try. The other 2 work fine enough for 60/40, but I'm pretty new to soldering, I probably cooked them too long last year.


I have an old old 100W or 120W Weller here, but that's big and bulky and the tip is huge.

I have a 858D hotair station. That worked on this type of solder before. I took out an 18-pin sister PCB. But I burned the main PCB doing it.

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