View Full Version : Soldering 101 or Soldering made easy

11-02-2008, 02:39 PM
I've noticed a couple of different people saying their soldering skills aren't that good. Well you don't have to be an expert to accomplish a good solder job. All you need are some basics so I thought I'd see if I could help out.

The solder iron:


You don't need to spend a lot of money on a soldering iron. I think I paid about $20us for this model. There are basically two types, irons and guns. Although a gun heats up much faster than an iron, I would recommend an iron over a gun simply because they are easier to control in cramped spaces. A stand and a sponge are a must! The stand, of course, keeps you from burning things up, while the sponge is used to keep your tip clean. This stand actually has a helping hands, but I removed it for the pic. If you are not familiar with the helping hands, all they are is a couple of alligator clips on articulated arms. They come in very handy when you are trying to solder two wires or small parts.


Something you want to look for is some kind of temperature control. This iron has a 15 watt and 30 watt setting. The lower wattage is great for things like circuit boards while the higher setting is used for soldering two or more wires together.


This is the business end of the iron. The screw allows you to replace the tip as they do eventually burn out. You can also install different sizes and types of tip as well, although, I personally have never had a use for a larger tip or say a chisel point type tip. Your uses may include one of these so don't be afraid to experiment.
Get a heat sink!


One more thing you will want in your tool box is a heat sink. This is a small clamp that you attach between the component you are soldering and the solder joint. This helps dissipate heat so you don't burn up the LED's you just purchased.

On to the soldering


Let's start with the solder. I all most exclusively use a .022 diameter solder. It melts fast and I don't get a big unexpected glob on my joint. In a lot of soldering tut's you might read how important clean wires are, how important flux is (flux is simply a cleaner) but if you are using freshly stripped wire, new components, etc...it's not really all that important because most modern solder contains a center core of flux or rosin. You do have to be careful as some wires do have a coating on them, but that is easily scraped off. After stripping your wire the first thing to do is "tin" the end. Tinning is simply impregnating a small amount of solder into the wire. To do this, as with any joint, you apply your heat to one side of the wire and the solder to the other side. The idea is to heat the wire to melt the solder and not melt the solder with the iron.


The finished tin job. This will make to much easier to make the connection and is especially important when soldering to a circuit board.


When connecting two wires this is the best type of connection. Not only does this help hold the wires together while you are soldering but it also gives you the best electrical contact area. Again to complete this joint apply heat to one side and your solder to the other. Don't forget to slip on your shrink wrap before completing the joint.


When soldering LED's, resistors, capacitors and other components you should use a heat sink. This will keep the component from getting to hot, and in the case of an LED, keep the plastic surrounding it from melting. Simply clip the heat sink between the component and the joint you are about to solder keeping the heat sink as close to the joint as possible.

Circuit Boards


When soldering on a circuit board I recommend using the lower heat setting on you iron. This will help prevent "lifting" of the copper etching of the board. It is pretty easy to ruin your board if you get it to hot. The heat one side, solder on the other technique still applies here though. You want the solder to flow around the wire not just glob it on.

Summing up

There are two kind of joints you can end up with when soldering, a hot joint or a cold joint. The kind you want is the hot joint. It will look shiny and smooth and will conduct electricity. A cold joint will be dull looking and not conduct electricity well. A cold joint occurs when the wire or joint is not heated to the melting point of the solder. A cold joint is easy to fix, simply reheat the connection until the solder flows easily. If you are in doubt about your connection simply get out you volt/ohm meter (you do have one don't you?) and check the circuit for continuity.

One aspect of soldering I have not covered here is "desoldering". Maybe you made the wrong connection or you want to remove a component from an an old circuit board but it is something you will at one time or another have to do. There are several desoldering tools that available. The most popular being the tube type. This is a metal tube with a spring loaded plunger. You cock the plunger, heat your joint, then use the vacuum created by the plunger to suck out the old solder. Personally I prefer to use whats called solder wick. This is a braided wire that pulls the melted solder from the joint. I find it much easier to use than the tube type.

I hope this shows you that soldering is not rocket science and any one can accomplish it. All it takes is the right tools and a little patience. Practice on some spare wire and some old boards then start your project.
It's easier than you think!

11-02-2008, 03:20 PM
Just wanted to add if you have any questions, feel free to PM me!

11-03-2008, 12:24 AM
Nicely done. +rep

What's your take on butane soldering irons? I own one with a few different tips and I love it.
Vapor genie vaporizer (http://vaporizer.org/reviews/vapor-genie)

11-03-2008, 01:25 AM
Nicely done. +rep

What's your take on butane soldering irons? I own one with a few different tips and I love it.

You know, I can't say I ever owned one. I've seen them but always figured that they would go through butane rather quickly. The last thing I want to do is run out of fuel half way through the build. I would also assume they would get to hot for delicate work, but we all know what happens when we ass-u-me! LOL!
How bout adding something on these to this tut? Do they use a lot of butane? is the temp adjustable? What uses do you find for the different tips? What about refilling, is a drop in cartridge or do you refill it like a lighter?
I'm sure we could all learn something. :think:

11-03-2008, 02:55 AM
Cheers man, nicely done ;) more rep for you!

11-03-2008, 06:00 AM
Great tutorial, I hadn't soldered in years and just recently started again and I've been forgetting to tin my wires because it had been so long. +rep

11-03-2008, 07:39 AM
I'd like to throw in what I've learned from my limited soldering experience.

I have two tips, one pointed tip like COntraptionMaker's and one that looks like a flathead screwdriver and I've found placing a little solder on the flathead tip and rolling the bare wire in that is the easiest method to tin a wire. In general, I use the flathead tip for wire-to-wire joins and the pointed tip for circuitry and other delicate joins.

As far as cleaning goes, before I begin I like to give the iron and the wire a rub with some sandpaper. It only takes a minute and ensures you get the best possible contact.

And I would say that helping hands ARE essential if you plan on doing even a moderate amount of soldering. They're not expensive (I picked mine up at a discount shop for $5) and now I wonder how I ever got on without them. They make the process so much easier.

Anyway, they're just my tips to add onto what ContraptionMaker said which nailed the basic principle perfectly. Good job!

11-03-2008, 02:29 PM
I've got a tip if you don't have helping hands and need something to hold your wires. If you have a multi-tool or needle nose pliers and you put a rubber band around the handle so it will hold some pressure on whatever is in the griping part of the pliers it will work nicely for holding wires for you.

11-04-2008, 10:22 PM
Butane Soldering irons are nice in a few places, like your no where near an outlet (IE in a tree, in a car, trapped on a desert Island). They are good at soldering wires and heavy lugs, but are not good for circuit boards.
If your going to do it get an adjustable solder station (http://shop2.frys.com/product/4825190#detailed) They can be had for $20. the bonus to them are when working on PCB (Printed circuit boards) you can keep it low (12W) but has the option to go up to a max of 50W when you need to solder heavy things (like battery cables). A semi-fine (2-3mm shaft tapered to a point) tip makes working on 3mm LED Leads a breeze (the fat 5mm Tips are only good for Wires and lugs). Also This helps melt the newer lead free solder, common in most all new electronics (ROHS, is the term you will see most) this lead free solder has a higher melting temp thus needs a slightly higher wattage. 15W is your best bet for PCB... the 30W will just burn off pads.

That's probably the number one thing that makes most first times solder job look so bad. Too much heat too, much solder, too much time with Iron on lead. also what kills more chips and transistors (the funny little tree legged half round or rectangle things on that board).

Good write up!


11-05-2008, 02:39 AM
Ok, here's the butane iron set I have. I got it at my local Wal-Mart for $20.


It comes with what amounts to a mini-torch on it that stays in place, on it in the pic, and then a sort of sleeve that slides over that and screws in place at the bottom, that accepts the soldering tips.


It came with four different solid tips:

A standard pointed tip (which I use most), a chisel tip (like a thick flat-head screwdriver), and two I've never used:


This one is sort of a round chisel tip, looks like it would be good for wide-area desoldering, but I can't think of an application where it would be good to apply solder.


This one is a hot knife, excellent for cutting plastic or nylon items that you don't want to fray, like rope. As you can see I haven't found a use for it either. :)

It fills from the bottom just like a refillable butane lighter, and while it does empty the tank on it fairly quickly, it refills in like 2 seconds, so no big deal. The main thing I like about it is the lack of a cord. As crazybillybob said, they're essential for work when you're nowhere near an outlet, and not having a cord just makes it easier to work with I think. Also the different tips and the availability of an open flame with the torch tip for heat shrink is nice. The disadvantages are as you mentioned, they are not adjustable (at least not this one) and they get HOT.

All in all, I prefer the butane iron, but that's probably because I never solder anything delicate. I wouldn't try it with this.
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