Soldering - bad tip care or soldering iron?

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I'm using a butane Iroda Solderpro 50 and having problems with the solder not melting well, not flowing.

If I try to tin the tip, I just get a blob build up and then fall off. If I try to heat the contact I'm soldering then introduce the solder, a ball forms and rolls away.

I'm re-soldering a loose contact on an SMD 3.5mm headphone jack - solder pad is easy to get to and about 2mm square, gold contact just lifting off the pad. If I leave the iron on the tab for a while, the solder below still wont melt yet if I introduce new solder it forms a ball on the tip and doesn't go on the join.


So is the iron just not getting hot enough (If I turn it up and hold the iron, it starts to go slightly red... and yet still the same situation). Or is it oxidisation on the tip? Or is the tip getting hot but not retaining heat when in contact?

I have both lead-free solder and some old, very thin leaded solder - same thing.

I've scraped the tip to see some non-black oxidised surface beneath but doesn't really make a difference.

Can anyone relate to my problem and what advice do you have to help the solder flow?
 
Nigel,

My infrared thermometer ( and the vast majority of them) reads the temperature not in the point where the laser pointer is located, but the average temperature of a circle wich the diameter is equal to half the distance of the thermometer to the measuring point.

this could be to large depending on the solder tip.

In my point of view the best way to measure is to use a thermocouple.

Thanks,
Flávio
 
Nigel,

My infrared thermometer ( and the vast majority of them) reads the temperature not in the point where the laser pointer is located, but the average temperature of a circle wich the diameter is equal to half the distance of the thermometer to the measuring point.

this could be to large depending on the solder tip.

In my point of view the best way to measure is to use a thermocouple.

Thanks,
Flávio

Mine reads soldering iron ok but you have to move it around to find hottest point. Same when I measure transistors temp on a pcb, the laser pointer isn't very accurate.
 
Before I venture to the tip temp bit, what's the best way of keeping the tip clean? I've some little pot of tip cleaner from Maplin that I've had a long while but it just seems to get a bit gunky with it. Perhaps I'll get rid of the top layer of the cleaner and see if it's better..
 
Damp sponge.
...

+1

...

I'm re-soldering a loose contact on an SMD 3.5mm headphone jack - solder pad is easy to get to and about 2mm square, gold contact just lifting off the pad. If I leave the iron on the tab for a while, the solder below still wont melt yet if I introduce new solder it forms a ball on the tip and doesn't go on the join.


So is the iron just not getting hot enough (If I turn it up and hold the iron, it starts to go slightly red... and yet still the same situation). Or is it oxidisation on the tip? Or is the tip getting hot but not retaining heat when in contact?

I have both lead-free solder and some old, very thin leaded solder - same thing.

...


Don't let the tip get too hot.
If you are lifting pads then the tip is too hot or you are leaving it on the pad for too long.

As a general rule (IMHO) 1-2 seconds should be sufficient to solder small smt parts. ( if they hold still )

Yes, red hot is way too hot.

Do not let it sit and smoke. (keep the flux off of it...keep it clean)

Do you have any liquid flux...very useful for smt parts.


Lead free is less forgiving than leaded solder...higher melting point...does not flow as well. IMHO

Try this:
Start with your iron cold.
Start it up and use it just after the tip will melt solder.
 
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I accidentally make a hole in a good linen tea towel with a sharp knife while drying the dishes whenever I need a new tip cleaner.

I dont use wet anything because it increases tip corrosion and oxidation. Just a dry wad of linen that I wipe the tip on. It is course enough to take left over flux etc off as well as polish the tip to the shiny surface.
Never use anything abrasive.
If the tip is pitted or looks damaged then replace it.

Your tip sounds like it is oxidised, I bet its dull and grey? If so wipe it, melt solder on it and repeat until the solder runs over the tip. If this doesn't work replace it.

Always leave a cover of solder on the tip if leaving it on and unused for a minute and, before turning it off always clean the flux off and leave a thick coating of solder on the tip.
 
Tip contamination can be a problem esp. when it doesn't respond at all to the usual wipe and go methods. Dip the offending tip in an old plumbers flux tin all is good again. IMO The worst kind of tip abuse comes from melting other things esp plastics. oh yeah old flux = acid based. ie chemistry
 
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Yes, that tip is oxidized, plus temperature is too high, which oxidizes it even more.
Agree with acid plumbers flux cleaning it, since it´s way more active, but it must be wiped away with a wet sponge or cloth since it´s damaging to electronic components and immediately tinned with safe solder.

And as mentioned above best tip temperature is "just above solder melting point" since it´s the least aggressive to tip.

I also use a gas heated iron sometimes but only for, say, outdoor jobs, such as on the roof soldering some antenna connectors, etc. ; definitely not for regular building or repairing stuff and even less for SMT parts.
 
What PRR said, smd with a gas soldering iron? That's like doing keyhole surgery with a butter knife.

But you can rejuvenate a tip very successfully with 'tip refresher'
tip refresher - Google Search

And doing anything smd without liquid flux is very hard, which is why your solder isnt flowing on the board, and just because the joint is lead free, doesn't mean it's going to be easier with lead free solder.
 
" Soldering - bad tip care or soldering iron?" Both and the wrong tool entirely.

Basically you have no temperature control I.E. it does not hold the temperature
steady at the tip and that is VERY important. The tip should NEVER glow.
The minimum grade of soldering tool I would put up with is a Weller Magnastat and
I have 2 of them though I rarely use them anymore. People I respect have good
things to say about Hakko irons. Personally I use a Metcal iron. I've been soldering
for over 50 years and would not trade it for anything though what I've read about
SBC tools, they may be as good. I've steered quite a few folks to Metcal and not a
one has bad things to say.

 
...or an extension cord.

For OP: The tip of a soldering iron should never turn red. That's **WAY** too hot. For leaded solder you're looking for about 380 ºC (700 ºF). If you're using lead-free solder, you'll need to bump up the temperature to more like 430 ºC (800 ºF).

It sounds like the reason your soldering iron won't tin is that you've run it way too hot and oxidized the tip. You may be able to recover it with a tip tinner (available from Digikey/Mouser/et al.) but more than likely you're going to have to replace it.

As others have pointed out already: Scrap the gas powered iron and get a proper soldering station instead – especially if you want to solder SMD. I love my METCAL MX-500, but it's probably a bit on the expensive side for the casual user. The Weller WES51 is a good one. Hakko makes one that's supposedly good as well, though I have no personal experience with it.

Also make sure you use solder that's fit for the job. You can read my thoughts on that here: Choosing solder: A guide for hobbyists and pros alike.

Tom
 
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