Using a soldering Iron, I can get the task in hand up to a level where the circuit/project actually works, but its very rough with spikes and often I get dry joint connections especially soldering onto new components, for example I am converting a some fancy decorative latters that have LEDS incorparated, they are designed to run on batterys, but as they are switched on for long periods I have converted them to run on a 3V DC power supply and using interconnecting leads between each letter, ie one Transformer supplies the three letters. The interconnects are 2.1 x 5mm power connections, BUT I cannot seem to get a neat and clean connection onto these plugs, I can mke the wire stick, but as above its not neat. What advice can you expert folks give me, should I be cleaning the connections of the components first with a flux. The solder I am using is a simple lead free solder from Maplins.....and the Iron I was using was a gas powered hand held unit, I have now purchased a decent soldering station, but have yet to use it. Any advice would be most welcome
Sondering is easy, but the tools are important, clean surfaces are important, the type of solder is important, and the flux is crucial.
If you don't get smooth solder connections you can have either not enough heat, no, or the wrong flux, and, or solder.
I solder with a smaller tip, and more heat. I wet the connection by getting solder on it, then push just enough solder into the connection for a clean smooth solder joint.
There is no substitute for experience, so once you know what is important, you can work on technique. If you try to solder bare copper, it has to be really clean, and you need good flux. The temperature you solder at, and the tip you use is all important. Consider that if you have heavy connections, thick wire, larger mass, it will require more instantaneous heat, so you would probably use a heavy, or thick soldering tip, because it can hold more heat. The bigger the tip is, the more heat it can transfer, and the faster the soldering will go.
Get good quality solder, kester is one, but there are others. The size of the solder should be gauged by what you intend to solder. Just remember these few important details, solder, Flux, soldering station/heat, and clean. Your work needs to be clean, you need good flux, you need the right size solder, and you need enough heat. The flux removes contaminates from the metal as it is heated, the flux helps the solder flow. Without flux, your solder won't flow, and you won't know what is happening. Small solder has a little flux in its core, and bigger solder has even more flux in its core. You can also buy rosin flux in a bottle, and put some on your work with a Q-tip. There are a lot of variables in soldering, so try something easy, understand it, then move on to something more difficult until you master it.