Flux Recommendation?

[lasersbee]

You can get a whole can at the hardware store for a few dollars, and it lasts for years.

Yeah I use that type when for plumbing, when you have to solder the copper pipes, I haven't tried it on electronics yet

Bah, flux is flux. It all works well. FP's stuff is >10 times the price. If it is better, it's certainly not 10 times better.

Flux is made of cheap and plentiful materials so there's no reason to doubt even the cheap stuff. Is a $7 box of saltines better than a $1 box of saltines? Probably not.

Sorry Cyp...

I'll need to strongly disagree with that...
There are 2 basic types of Flux available at the Hardware
store..

For tinsmithing and plumbing there is ACID Flux.
For electrical and electronics there is ROSIN Flux.

ACID Flux should NEVER be used on Electrial or Electronic
circuits because over time if it is not completely removed
it will corrode the solder junction area...

Been there done that...

Only use ROSIN Flux for Electrical or Electronic assembly.


Jerry

You can contact us at any time on our Website: J.BAUER Electronics

 

[Blord]

I never use separate flux in my build. The solder tin with rosin core works the best. It is very convenient stuff.
And yes don't use acid base flux for electronics. In time it eats away the wire and the pcb board.

 

[Cyparagon]

Rosin flux can be used for plumbing too.

electronics: joining copper wires with lead and/or tin
plumbing: joining copper pipes with lead and/or tin

Good point though. Be sure to choose a flux that doesn't have acid on the label.

 

[Things]

I never use separate flux in my build. The solder tin with rosin core works the best. It is very convenient stuff.

Same, never used separate flux. Although it can come in handy for very tiny SMD work if you're doing it by hand, and the pads are fairly oxidized.

 

[Bionic-Badger]

I use Kester 1544 flux that I was lucky enough to get in a convenient quantity (2x 50ml bottles with syringe tips). It's good stuff: highly active, non-corrosive, doesn't require cleaning (though you should anyway), and not that expensive ($50/gallon). However, you can only buy it in large quantities (1 gal or more), which is way more than I'd ever use, and the hazardous materials transportation costs would increase the cost somewhat. If you use a lot of flux, it might be worth the quantity purchase given its relatively low price and level of quality.

 

[ryansoh3]

I use Kester 1544 flux that I was lucky enough to get in a convenient quantity (2x 50ml bottles with syringe tips). It's good stuff: highly active, non-corrosive, doesn't require cleaning (though you should anyway), and not that expensive ($50/gallon). However, you can only buy it in large quantities (1 gal or more), which is way more than I'd ever use, and the hazardous materials transportation costs would increase the cost somewhat. If you use a lot of flux, it might be worth the quantity purchase given its relatively low price and level of quality.

Wow, you're very lucky to get a nice quantity of the flux.

Is anyone familiar with the "rosin flux pen" that ebay sells for 3 bucks?

Something tells me that it won't work too well.

Thanks! :beer:

 

[lasersbee]

If you use Rosin Flux core Solder you should have enough
Flux in the solder's core to do good solder joints without
requiring extra flux.

Extra flux is only required if the Joint has become dry because
of repeated re-heating of the joint and the original flux has burnt
off.


Jerry

You can contact us at any time on our Website: J.BAUER Electronics

 

[ryansoh3]

If you use Rosin Flux core Solder you should have enough
Flux in the solder's core to do good solder joints without
requiring extra flux.

Extra flux is only required if the Joint has become dry because
of repeated re-heating of the joint and the original flux has burnt
off.

Jerry

Oh... Well, I guess I'm just really bad at soldering. Even if I do use rosin core solder, wires and contacts just don't seem to cooperate. :yabbem:

Thanks for the reply. Cheers!

 

[Things]

Are you tinning everything individually first? Trying to solder bare wires and contacts together is just asking for issues. Apply solder to the contact and bare wire first, then all you have to do is hold the wires/contacts together, touch the iron, and you're done. Most of the time you don't even need to apply solder - a free hand for holding wires!

 

[ryansoh3]

Are you tinning everything individually first?

Yeah, tinning, in my opinion, is the hard part. If I melt the solder, it just falls off and hits my working table. Should I be using extra flux on the wires?

Thanks! :beer:

 

[Things]

How I usually do it, is put the iron underneath the wire. Feed a small amount of solder onto the iron itself, so it flows down and makes good contact with the wire, to help transfer heat. Then don't add any more solder to the iron, add it to the wire. Eventually the wire will get hot enough that the solder will melt directly onto the wire.

If you melt the solder onto the iron first, then just touch it to the wire, the flux has already burnt off. You need to apply the solder to the wire as you're heating it.

 

[ryansoh3]

If you melt the solder onto the iron first, then just touch it to the wire, the flux has already burnt off. You need to apply the solder to the wire as you're heating it.

Oh, that's where I was doing it wrong. :banghead:

All the time I've been wondering why the heck soldering was so hard for me.

For a while, I've been blaming it on my old soldering iron. :crackup:

Thanks for the tip! You just make my life much easier. :beer:

 

[Cyparagon]

There are some cases where applying solder to the iron is easier. If the joint is a hard-to-reach area for example, I apply flux to the joint beforehand so only one tool has to be in there at once.

Also, it frees up a hand. There are some jobs where it's just quicker to use flux on the joint rather than fiddling with third hands.

 

[Things]

Heheh, no problems.

Just keep trying at it, trying new things, eventually soldering requires no more thought than breathing.

While I do still occasionally blame things on my equipment, my soldering iron is only a $12 non-controllable direct plug in one. That's what I've been using for the last 8 years, and probably what I'll use for another 8. It's all about the technique

EDIT: And yeah, what Cyparagon said is where flux really comes in handy, but most of the time just plain rosin core solder is fine.

I also try to avoid the lead free solder, and use the typical 40/60, as I've heard lead free solder doesn't flow nearly as well, and, well, as long as you're not eating your solder, it's fine.

 

[ryansoh3]

There are some cases where applying solder to the iron is easier. If the joint is a hard-to-reach area for example, I apply flux to the joint beforehand so only one tool has to be in there at once.

Also, it frees up a hand. There are some jobs where it's just quicker to use flux on the joint rather than fiddling with third hands.

Yeah, I might need to get some flux for that.

Heheh, no problems.

Just keep trying at it, trying new things, eventually soldering requires no more thought than breathing.

While I do still occasionally blame things on my equipment, my soldering iron is only a $12 non-controllable direct plug in one. That's what I've been using for the last 8 years, and probably what I'll use for another 8. It's all about the technique

Thanks for the inspiring works. I'm using my dad's iron, god knows how old it is. Thinking about it, it's over 11 years old because it runs off 110V, back when my family was in the US. (Korea uses 220V.)

I guess it's like a generation hand-me-down items. :crackup:

Cheers! :beer:

 

[Things]

Well, if it still works, why not

I think I've been through about 3 of these irons in my electronics lifetime, twice from dropping them and breaking the element, and once because the tip corroded so badly you could almost see thought it (And new tips were more expensive than a brand new iron!)

Because of this, so far I haven't been convinced to switch to a temp controlled station, though I am looking at a cheap hot air station next time I find some funds. I've done everything from heavy gauge wire carrying over 40A, to TQFP packages with the same iron, and never had any issues, but hot air and solder paste is far superior for SMD.