Tinning a soldering iron

September 17, 2008 9:26 AM

How do I get solder to stick to the tip of my fancy new soldering iron?

So I just got a "real" soldering station with adjustable temperature and the whole bit.

Link to the solder I'm using.

Set the temperature nob to 350c and try as I might I can't seem to tin it, 60/40 solder just runs off. This is a brand new iron with a conical tip. The tip has blackened as the result of my efforts and isn't conducting heat well.

I've lightly filed off the black deposit, wrapped the whole tip in solder and reheated it but still no luck, solder just runs off and the tip blackens again after a few seconds.

Is the tip of my iron ruined? Am I doing something wrong?

posted by shimon to Technology (9 answers total)

I might not have done the type of soldering you're doing, but when I've done it before, the point wasn't to have the solder stick to the iron in the first place - it's not glue, it's metal. You use the iron to heat up the elements that you're soldering together by holding it to the elements, while you also place the end of the solder wire where you want it to go. Eventually, the elements heat up enough that they melt the solder and you then remove the iron.
posted by LionIndex at 9:47 AM on September 17, 2008

I didn't think it was *supposed* to stick to your soldering iron. The iron heats the object piece and the solder that you are holding against it. I don't think you're supposed to use the iron to transfer the molten solder to the object (if that's what you're trying to do). Do a little internet search for best soldering techniques, it's been awhile since I did any.
posted by Xhris at 9:47 AM on September 17, 2008

I think the poster is interested in having a tinned tip, which greatly increases the heat conductivity and makes soldering much easier. I also have a hard time tinning with normal solder, so I use tip tinner, which works very well. Also, I've found that having a pre-tinned tip makes it much easier to keep it that way.
posted by zsazsa at 9:54 AM on September 17, 2008

I've had mixed success with the new lead-free solders. But when the solder won't flow on the tip at all, in my experience it means the tip is no good. Some inexpensive tips have just a plating on them and when that's gone (often caused by overzealous cleaning/filing/sanding) the tip is ruined. I've had good luck with genuine Weller tips. You could try one of the special tip tinners (goop that comes in a cup that you dip it in), but I bet a new (better quality) tip is what you really need and you won't be happy with the operation of your new iron until you get one.
posted by fritley at 9:57 AM on September 17, 2008

I think the poster is interested in having a tinned tip, which greatly increases the heat conductivity and makes soldering much easier.

Yeah, I checked some of the articles buggzzee linked to, so that's clear now. Sorry for the misunderstanding.
posted by LionIndex at 10:00 AM on September 17, 2008

I find that scuffing it with a little sandpaper helps sometimes.
posted by electroboy at 10:53 AM on September 17, 2008

Best answer: wrapped the whole tip in solder and reheated it

Wait, what? You let it cool? File/sand the tip with it at working temperature and immediately melt the soldier onto it. If you wait too long it tends to form a layer of oxidization that will prevent it from taking. Also RS sells a little metal tin of cleaner that does wonders. It cleans and re-tins at the same time.
posted by Rhomboid at 11:29 AM on September 17, 2008

Best answer: Yeah, the tip has gotten too hot and oxidized. Clean the oxide off the cooled tip with sandpaper or a file down to bare metal. Then heat the tip slowly, touching the tip with the end of your roll of solder. As soon as the tip is hot enough to melt the solder, turn the heat down so the tip doesn't overheat (again) and melt the solder all over the tip. Now your tip is properly tinned.

After soldering with it for a while, a black crust will intrude on the tip. Wipe that off with a crumpled paper towel moistened with water (or a damp sponge), so you see a nice, bright, shiny tinned tip. That's what you want to solder with.
posted by exphysicist345 at 3:12 PM on September 17, 2008

Response by poster: Thanks guys, cleaning the tip gently on some wire wool with the iron heated to around 275c seems to have done the trick :)

Also, the solder I'm using is pretty thin so it might not have enough rosin to coat the tip properly.
posted by shimon at 8:56 PM on September 17, 2008