Hi

I have now had the following problem for the hundredth time and it is getting on my nerves like nothing else:

Buying a new soldering iron, buying new solder and finding that the solder does not want to stick to the soldering tip AT ALL. I mean, I am heating up the solder till it is ready to evaporate, but it goes everywhere else, on the table, on the carpet, but the soldering tip is like oil and the solder is like water. No mixing. I have had soldering tips that worked, once it sticks, it does. But I never figured out how I managed to do it. Same thing with a copper cable (exposed): The solder does not want to bond with it. I just found enough annoyance to write this mail watching a cable melt (the metal lead coming out of the mantle) by heating it forever and still it won't work.

It seems to me that the connection (solder tip to copper) is not transfering the heat at all, but on the other side, I could be frying the circuits by heating them so long.

WHAT AM I DOING WRONG?

I am sure that I am not the only person that has this problem. Do I need something else than just solder and a soldering iron?

Markus

When I solder, I only move the wire and not the iron. The iron shall be placed steady on the target wire or plate and the wire should be slowly joined to it. The lead shall flow around the target wire or plate. Note that the target wire or plate should be hot enough so that the lead won't be separated when you detach the iron. After that gently pull the soldering iron and that's it.

Mmm, it's been a while since I did any soldering...but I seem to remember something called flux, either in cored solder and/or separately, helps.

Take a piece of fine sandpaper and sand the tip slightly before starting. Using flux will of course help also. Anytime later that you again have the problem, use the sandpaper again. I usually clean the tip when finished by wiping it off with a piece of plain cardboard.

Sounds like you have yourself a type of solder that requires the use of flux.
While having a small brush-cap bottle of flux can be handy at times, I would suggest getting yourself some rosin core solder instead as it is safer (both for you, your environment and your materials - some flux types can chew through materials if not cleaned off properly after use).
Prefer the environmentally friendly kind.

NEVER neverrrrrrrr ever use sandpaper on soldering iron tips! When you sand the tip you sand off the protective cover of the tip, causing irreparable damage. The tip will be rapidly erode by the acids in the flux of your solder without it's protective cover.
If you want a cheap solution to a 'soldering sponge', just get yourself a plain, fine sponge made of natural material ('sea sponge' for example, not a synthetic sponge as it will melt!) and make it slightly wet before use.

In agreement with rosin and natural sponge, and in disagreement with sandpaper.

To add:
- Keep the sponge damp, and wipe the tip of your iron on it every couple of minutes to clean the residue off it.
- Apply rosin to the contacts on your components. Once you do this, the sold should flow nicely from your iron to the contact point
- You should also only turn your iron hot enough to melt the solder so that it will stick to the components.

Also, I believe there is a difference in the type of solder you should use. Some are made for electrical use, while others are not.

Another vote for the wet sponge treatment.

Thanks for the suggestions. I mean, it is not like this soldering iron is old and overused, it is brand new. Do they coat it with something that preserves the metal, but makes it impossible to get solder to stick to it?
The solder melts, but then forms a ball, that wants to go EVERYWHERE else than the tip. The solder is supposed to have flux included.

Strange.

But I will try the sponge treatment.

I will also sand paper the tip a little, maybe it is too smooth. It is a total cheapy soldering iron, so no danger of losing much money.

Markus

From the factory, most metals have some oily residue.

Try the sandpaper.

Which kind of solder do you use ?
Which core inside ?

+1 for flux. Solder for use with electronics usually has a resin core flux.

Also, tin your tip.

Take a piece of very fine sandpaper and lightly sand the tip -at least before you use it the first time. Then dip the tip in the flux and turn on the iron. When it is hot enough to melt the solder, tin the tip with solder -this means that you keep working the solder onto the tip until the tip is cover with a fine layer of solder.

Once this is done the tip is ready to use.
Apply the tip to the objects which are to be soldered until *they* are hot enough to melt the solder. Do not heat the solder itself and let it drip onto the connections as this does not provide a mechanically-fast connection.

When finished, wipe the tip with a damp sponge or dry thin cardboard so that the 'tinning' is preserved.

Do not ever use acid-core solder on electronics or electrical connections. It is for use when soldering plumbing-pipe connections. You can use rosin-core solder, but I prefer to use the separate rosin called flux. Make sure it is for electrical soldering.

If the solder won't flow on the tip, the tip is contaminated. The sponge technique is the only one to use; sanding tips ruins them.

You can sand your copper wire though. I have occasionally done that. Typically though if the solder won't flow onto the copper it is corroded or contaminated.

NEVER use a solder with acid for electronic soldering. Use rosin-core solder ONLY. You can use solid solder and external rosin, but I find it is just easier to use an electronics-grade rosin core solder.