On Mon, 16 Aug 2010 17:34:22 -0400, "Ralph Mowery" wrote:
"Bob Eager" wrote in message
...
On Mon, 16 Aug 2010 18:43:08 +0100, john hamilton wrote:
I have to connect this AAA battery holder to a toy. Although I have a
small soldering iron, my soldering skills are poor. I can see myself
easily melting all the plastic around the contacts before I can get
anything to stick to the tabs.
To add to the other suggestions about soldering: if you can get/borrow a
temperature controlled iron, run it at a lower temperature and use 63/37
solder.
That is usually the wrong way to do the job he wants to do. Use a very hot
iron, hit the joint fast with a lot of heat and then get out quick. The
tabs will get hot very quick and melt the solder. If he applies a low heat,
the plastic will get a lot of heat on it before the tab gets hot enough to
melt the solder.
The 63/73 is the way to go, but 60/40 is just fine. Also do not move the
wires while the solder is cooling. This is one big way to mess up the
joint.
I'm surprised nobody mentioned cleaning up the battery tab first,
some of that cheap gear is terribly difficult to tin, without a
good scratching up and cleaning first. Emery paper, sand paper,
even a sharp instrument. And wash the grease off too, metho or
IPA should be safe for the plastic?
The trick is to go in quick, if it doesn't work straight away (like
less than a second), remove the heat, let the thing cool right down,
and try again later.
Problems happen when you keep the heat on to no effect, melting the
surrounds.
Be aware of the need for the fresh heat bridge, created by applying
iron and solder together, so the flux is working. It's perfectly
fine to have several attempts, provided you let the parts cool right
down between the attempts.
And yes, practice makes perfect, so try some other soldering to get
a feel for how the solder, flux and iron behave together.
Try soldering (stripped) insulated wire together until you can make
clean solder joints without burning the insulation, basic thermal
feel and control. Don't be afraid to waste solder, learn to coax
excess solder off a joint by application of the iron and new solder.
Grant.