Soldering Electronic Joints

This page describes how to solder electronic components using a soldering iron. If you came here looking for advice on recreational drugs then I am afraid you came to the wrong place. The page evolved out of an article I posted to the rec.audio.high-end Usenet newsgroup in September 2000. It has been modified for clarity and to make me look good.

Type of Solder

Just make sure it is intended to solder electronic parts and not, say, coffee pots.

Soldering Iron

For soldering of electronic parts, a low-power iron requires less skill as there is less chance of the components being baked. Some people swear by irons that can be set to different temperatures. If you buy one then set the temperature to whatever is recommended on the packet of solder.

Technique

The "approved" technique is:

1. First tin each of the components separately. ("Tin" just means to coat with solder.)
2. Bring the two components into contact and hold.
3. Touch a hot iron with solder to "wet" the tip.
4. Touch the two components with the hot iron for a very short time, only long enough for the two coatings of solder to merge.
5. Do not use the iron to carry solder to the joint.
6. Do not feed extra solder into the joint while the iron is in contact with it.
7. Keep holding the two components in contact until the solder cools and solidifies. Do not wiggle them to see if the joint is solid yet.

To Blow or Not To Blow

There is much argument on whether blowing on the joint to speed cooling is A Good Thing or not. Do not blow but, instead, let the joint cool naturally. This will produce smaller crystals in the solder, and so a stronger joint.

Heatsinks

A long time ago, I bought aluminium "tweezers" that clip to the legs of components and absorb heat. If you can find these then use them, but if your technique is good then you do not need them. Electronic parts are designed to be soldered; if soldering damages them then there is something wrong.

Have fun.