Desoldering methods

[Frugivore8894]

I don't know what this would possibly go under maybe hobby tech? But its here for now. So I want to desolder a lot of stuff (a full mechanical keyboard) and I am not going to buy a expensive fancy shmancy Hakko gun. So I have found a few other methods.

 

• Pump
• DYI/Shop Vac
• Cheap thing
• Not safe at all

So what's the best option?

[SimplyChunk]

I use a device similar to the first one:

 

 

I also use some desoldering braid

 

but you HAVE to wet the braid with some flux.  I use a pen:

[LateLesley]

How about the cheaper-than-hakko option? 

https://www.ebay.co.uk/itm/324166943523?hash=item4b79db0323:g:40kAAOSwIlBeplWb

 

I mean a desoldering pump will work, but they are a pain, and not too efficient. Desolder braid might be better. 

[CrEaToR VR]

Desoldering Wick (braid) is easy to use, and can be better than a desoldering pump in some cases.

[Mark Kaine]

desoldering pump is only used for some difficult cases, otherwise you use braid, its so much easier.

 

1 hour ago, Frugivore8894 said:

I want to desolder a lot of stuff (a full mechanical keyboard) and I am not going to buy a expensive fancy shmancy Hakko gun.

we have a saying here "those who buy cheap, will buy twice."

 

 

[tkitch]

Desoldering Braid FTW

[Frugivore8894]

Ok it seems the braid is the way to go. I didn’t include it because I wanted a video that said it was hard and you needed to be a very good solderer to do it but literally everyone is saying otherwise. 
 

 

9 hours ago, LateLesley said:

How about the cheaper-than-hakko option? 

https://www.ebay.co.uk/itm/324166943523?hash=item4b79db0323:g:40kAAOSwIlBeplWb

 

I mean a desoldering pump will work, but they are a pain, and not too efficient. Desolder braid might be better. 

and as for this it looks good but it’s about twice as much as I am spending on switches  so not sure it’s worth it. If I were to ever need to desolate again it might be but at the moment I don’t think it’s the right option. 

[minibois]

In my opinion a good solderpump is preferred for desoldering through-hole components (like mechanical keyswitches). If the solder on the board currently is without lead, some leaded solder added can help too.

Again, in my opinion solderwick is for SMD parts, not THT, but of course people can disagree on that.

[Frugivore8894]

12 minutes ago, minibois said:

In my opinion a good solderpump is preferred for desoldering through-hole components (like mechanical keyswitches). If the solder on the board currently is without lead, some leaded solder added can help too.

Again, in my opinion solderwick is for SMD parts, not THT, but of course people can disagree on that.

I might try both on a something cheap form eBay.

[mariushm]

You'll probably have a horrible time with desoldering braid.

 

My preferred choice would be your option 1, the solder sucker/pump BUT :

* never get the cheapest. Get one that's longer, and preferably made of metal. The engineer one is great.

Get some silicone tube, cut a small piece of it and slide the tube over the nozzle. The silicone can handle very high temperatures, so you can put the silicon tube right on the melted solder and suck it with the pump.

That's the trick - a lot of pump users use it wrong because they don't put the nozzle tip right on the solder or lead, because the plastic tip starts melting.

The way I do it is ADD a bit of solder which also happens to have flux in it, so the flux helps attach the oxides on existing solder and make it flow easier. Then I bring the solder sucker at nearly 45 degree angle, and put the nozzle on the actual solder, bring the iron tip to make it melt and suck the solder up.

 

Cheap solder braid won't have flux in it and flux is critical. You can wet the braid with flux but it's a pain in the a$$ even then.

You'd still want to add some leaded solder to lower the melting point of the lead free solder used, and if you're unlucky the holes will be so narrow that solder will remain stuck between the leads and the hole, and not want to be wicked into the solder braid... if you spend too much time trying to whick solder you can actually damage the pads or the button from too much heat.

 

 

[Frugivore8894]

48 minutes ago, mariushm said:

You'll probably have a horrible time with desoldering braid.

 

My preferred choice would be your option 1, the solder sucker/pump BUT :

* never get the cheapest. Get one that's longer, and preferably made of metal. The engineer one is great.

Get some silicone tube, cut a small piece of it and slide the tube over the nozzle. The silicone can handle very high temperatures, so you can put the silicon tube right on the melted solder and suck it with the pump.

That's the trick - a lot of pump users use it wrong because they don't put the nozzle tip right on the solder or lead, because the plastic tip starts melting.

The way I do it is ADD a bit of solder which also happens to have flux in it, so the flux helps attach the oxides on existing solder and make it flow easier. Then I bring the solder sucker at nearly 45 degree angle, and put the nozzle on the actual solder, bring the iron tip to make it melt and suck the solder up.

 

Cheap solder braid won't have flux in it and flux is critical. You can wet the braid with flux but it's a pain in the a$$ even then.

You'd still want to add some leaded solder to lower the melting point of the lead free solder used, and if you're unlucky the holes will be so narrow that solder will remain stuck between the leads and the hole, and not want to be wicked into the solder braid... if you spend too much time trying to whick solder you can actually damage the pads or the button from too much heat.

 

 

Thx sounds good! 

[Mark Kaine]

On 8/21/2021 at 12:53 AM, mariushm said:

You'll probably have a horrible time with desoldering braid.

I know its an old post, but that really depends... in my work we use it a lot for desoldering and its actually fun to use, although i will say still difficult because of all the heat, its actually easy to kill a board this way...  but we basically only make SMD , if something needs a solder pump no one wants to do it, we have only 1 worker who knows how,  and she hates it too lol...  ps: the flux thing... isn't that *in* the solder? (I'm 99% certain it is)

 

Ps2: oh we have some spray that's always used when desoldering,  i always think its for cleaning,  but it might also contain  flux? Well anyways,  I think desoldering with braid is really fun !

 

Btw, I get it - these are technically not SMD (although they're literally...) but the department im working is literally called  "SMD" (ironically)

...

 

 

The circled holes is what I usually have to desolder  (ie remove the solder) it doesn't happen often because for it to happen someone needs to mess it up first obviously  (usually something went wrong with the reflow machine i guess, but it really happens  rarely)

[mariushm]

There is flux in solder, but in small percentage, usually enough for soldering clean pads and leads, which basically have minimum of oxidation.

It always helps to add extra flux if the surfaces are dirty.

In addition to this, if you work with very thin solder wire, like 0.4mm or less, the flux in the solder wire can burn out before it hits the surface if the soldering iron is too hot.

 

Wick is only effective if it's impregnated with flux, it improves the ability of copper strands to pull solder, that capillary action. A lot of cheap solder wick has very little or no flux. An amateur may have difficulty using the wick and may apply too much pressure or rub the wick against the pads making the break off. 

This was actually my experience with my first solder wick lots of years ago - I got a 5$ roll because the other options were 10-15$ and it turns out my roll had no flux and was frustrated and wondering why mine doesn't work like in Youtube videos... and then I learned about flux.

 

[H713]

If you're doing SMD desoldering, wick is the way to go and works fantastically. It is also the way to go for single-sided through-hole boards that don't use plated through-holes (PTH). 

 

Pumps are useful for removing big globs of solder from big through-hole parts, connectors, point-to-point wiring terminals, etc. IMO, that's about all they're good for.

 

The right way to do through-hole desoldering, particularly on boards with PTHs, is a vacuum desoldering station. The Hakko FR301 (I think that's the model) is pretty good. The Metcal DS1 is better, but requires compressed air and costs a small fortune. 

 

You can also desolder through-hole chips with a hot air station. IMO, this is probably the easiest on the PCB itself, but can be hard on surrounding components.