Simple Soldering

[geofy]

A small soldering iron from shops like Maplin, a 15 Watt iron like an Antex for example, a small pack of solder and tag strip and insulated wire to practice with. A pair of wire cutters pliers and wire strippers and away you go.

Make a good mechanical joint on a clean tag, bring the hot 'tined' soldering iron and solder to the joint together and melt and flow the joint quickly to give a smooth shinny outline.

Easy Peasy

Geof

[davidw]

Yep it's as easy as that..BUT remember CLEANLINESS is vital .Some component leadouts are not clean enough especially if they have been stored for any time.

[Nickthedentist]

Frankly, I'd always use traditional leaded solder for our hobby. It's much easier to work with and requires lower temperatures to work well. It's also more obvious when joints are bad ("dry" or "cold").

Note that strictly speaking, a "good mechanical joint" is not required at all, BUT you must ensure that the items to be joined are held absolutely steady until the solder has solidified.

N.

[julie_m]

I'd be inclined to say it's well worth shelling out the extra for a thermostatic iron. Without having to rely on the air and the joint taking heat out of the tip as fast as the element is supplying it, such irons can be rated at 50 or 60 watts -- but they may only be on for 1/4 of the time. It might sound counter-intuitive, but the fact of having a higher wattage can actually reduce the risk of collateral damage; you don't have to wait so long for the heavy tag and thick wire to heat up to the melting point of solder that they spend a long time sitting at the melting point of plastic insulation (or germanium semiconductors!) Also, while this is happening, the flux is burning off and the surface exposed to the air can oxidise.

I've used both thermostatic and traditional soldering irons, and I know which I prefer. No doubt some people might want to "keep it pure" and do everything using "period" tools, but I'm not such a masochist.

The point of having a joint that is mechanically sound first is twofold. Firstly, you don't want anything to move while the solder is solidifying for fear of weakening the connection. Secondly, if the wire and the PCB trace or tag are directly touching then the main current path will be direct from one to the other, not through solder -- which isn't really such an amazing conductor. However, you will regret wrapping a wire around a tag when you have to unsolder it later! Use a small vice and/or a pair of "helping hands" -- crocodile clips on an articulated joint arrangement, often fitted with a magnifying glass -- to hold everything in place.

You may need to use fine sandpaper or wire wool to remove any oxidation from component leads, but take care then not to contaminate them with abrasive material -- wipe them on a clean, dry cloth afterwards.

[wireful3]

I also follow Nick's preference for leaded solder for the same reasons.

I was always taught that after cleanliness the basis of a good soldered joint was a good mechanical one but have often wondered why. I suspect as Nick and AJS say that keeping the joint still during soldering is the crucial thing. Threading the wire through the eyelet and then wrapping it securely around the tag may be going a bit too far and it certainly makes afterwork a problem.

As others have said cleanliness is most important and I would recommend lots of practice before trying anything serious. I have seen beginners meticulously do all the things they were taught and still have problems. On the other hand skilled wiremen seem to be rather casual but make perfect joints with no trouble. As one said to me he had lots and lots of practice.

[AlanBeckett]

I agree with AJS. I spent literally years in my last lifetime trying to explain to the shop floor the difference between temperature and heat capacity. A small iron and tip was seen as a 'good thing' for small(ish) components, but when they couldn't get a good joint the answer was to turn up the temperature - grrrrrr.
I remember when the Weller was first introduced. The power was seen as enormous. But of course it was the temperature control that fixed it. I still use a Weller or two, and I've noticed them on several benches in posted pictures.
Alan

[HG MICKE]

At college we were taught, for point to point wiring, to always make a good secure mechanical joint before soldering as the joint is not only electrical but has to support the component.
In fact we had to make a wired unit that was tested before we were allowed to solder it up.
One thing about lead free solder that we ran into,in the course of our business, is that it can react badly over a period of time with old fashioned leaded solder.
We found that we had a fair number of sets where the joint on the PCB ,on components that we had replaced,had broken down.On inspection there was a black film between the joint and the PCB,this could have been due to the more aggressive flux used in lead free solder or a reaction to the silver content in the solder.
We now use lead free solder only for new build or repairs to newer equipement that used it in its manufacture,for all other work we use standard 60/40 leaded solder.

Colin

[XTC]

If you are using components which have been around for a time, the leads will have tarnished and they'll be difficult to solder. This is also true when soldering in old sets. I find running the leads through a slip of 1000 grade wet and dry gets rid of the surface oxidation and it makes a better joint, easier.

Veroboard which has been hanging round in a drawer for ages also tarnishes and can be hard to solder. It's worth cleaning it up before trying to solder to it.

Pete.

[geofy]

Originally Posted by Nickthedentist

, a "good mechanical joint" is not required at all, BUT you must ensure that the items to be joined are held absolutely steady until the solder has solidified.

N.

Ideally the solder should just be there to support the joint and the circuit should work with just the mechanical joint being good enough. But it is now the norm to have lay on joints as well as surface mount which rely just on the solder to hold everything in place. And with non lead solder a shinny joint cannot be made, very often a good joint will still look dry and dull.

I only put this very basic sketch up because fortfeeder (John) said he couldn't solder and I wanted to show that it is an easy thing not requiring books, only an iron and a few bits and pieces. It could be much more involved to show a good and bad joint etc; as very often all that is wrong with an equipment fault is a poor soldered joint.

Geof

[Top Anode]

I brought my Antex 50w to Texas. Ready to contrive a 220v supply, I thought I'd just try it first. It worked fine! Soooooo much in reserve. At home, it really did pour in the heat when you needed it.

So important to remember not to put it in a heat-sink!

By the way. When did the use of a wet sponge become the norm for cleaning? I don't recall them at all when I was in the trade originally.


Here, I had to remove the instrument panel in my Chevvy. It had the tube type displays, and below a daughter board there were 156 dry joints. The trouble was that the original solder was a very high melting point product. But, it all worked.

I'm pleased to see that one can still get led/tin? solder. In the ordinary Radio Shack type places I haven't seen it displayed for many years. Do you have to send to specialist places for it?

I soldered the rotary-switch in my first ever multi-meter with a huge Solon iron. It would've been better employed by a plumber! Nice that was, made the dovetail joined box at school in woodwork.

[evingar]

Originally Posted by Top Anode

By the way. When did the use of a wet sponge become the norm for cleaning? I don't recall them at all when I was in the trade originally.

A wet sponge can be bad news if you are using a Metcal soldering iron - The thermal shock soon destroys the tip if the sponge is other than just slightly moist - I very rarely use a sponge at work at all - We have what looks like an ash tray full of what looks like fine brass lathe skimming. A guy we had working for us (from an electronics construction company) suggested it - Works brilliantly on all iron types.

[AlanBeckett]

Hmmmm......
I think wet sponges came in with Wellers in the early 70s. The original genuine sponges said 'keep very wet'. It works fine with their iron coated bits provided you don't leave them lying around wet, in which case they go rusty

[Boom]

I use a good old fashioned tin of Fluxite or Telux to dip the bit in and a dry cloth to wipe it with. Keeps the bit clean and doesn't eat it away either.

[AlanBeckett]

David,
You'll be using Baker's fluid next!
Alan

[Boom]

Alan there were times in the past that I used Spirits of salts as the flux and a lump of old lead water pipe to solder wires with.

[AlanBeckett]

David,
[This is on the ragged edge of OT]
I once watched an old plumber, about 25 years ago, wipe a beautiful joint on a lead pipe using an old Woodbine packet he found under the floor.
Yes, I've used that many moons ago, but only for metalworking. I was in the fortunate position as a teenager of knowing someone who worked for Rists Wires & Cables. We asked her to bring some solder home, whereupon she produced a 7lb reel! It lasted for years.
I really do prefer to stick to my trusty Weller, with a reasonable sized 700 or 800 bit. The temperature is well controlled and there's penty of heat capacity so you don't need to be 'on the joint' for very long. Ideal for valves I'd say.
Alan

[kalee20]

* A damp sponge for cleaning the bit

* A temperature-controlled iron (Weller Magnastat type, with bit temperature grade No. 7)

* 60/40 solder, 18SWG

This is my ideal selection for soldered joints. RS still sell 60/40 tin/lead solder, although I can see the sales going down as the demand reduces.

For heavy joints, such as to pressed-out chassis tags that one often finds on steel chassis, a more powerful iron is needed (I use a Weller 100W iron for this).

Fine steel wool is slightly better than grade 1000 abrasive paper, because it doesn't shed minute abrasive particles which become embedded in the surface of the wire. But, I hardly ever find I need to use it.

[Boom]

Yes very much on topic Alan. Here is my iron that I use for such things as vintage electrolytic tags, Thorn tuner bars and obstinate DIL ic's.

The bit is half inch diameter chiselled to a point. No earth leakage to worry about neither.

[AlanBeckett]

David,
I blundered horrible a few weeks ago and I'm still kicking myself. I was at a local auction and there was a beautiful blowlamp complete with (big) soldering bit. It wasn't a bodge, it was the real thing. Anyway, I went for a cup of tea and missed. Not only that, it went for peanuts.
Alan