> I've found myself in a familiar position of having to solder some
> wires into a DIN plug. [...] The problem is that I can't seem to get
> the solder cup hot enough to get the solder to adhere before the pin
> melts the surrounding plastic.

One aid I've found is to insert the plug into a mating socket before
soldering to the pins.  Female socket helps hold the pins in place.
And ensure that you have a high enough wattage iron to rapidly heat
the end of the pin when soldering on the wire.

> 3) TRY to tin solder cups - solder seems to not want to stick -
>    end up with a blob on the iron.

Possibly buy a better grade of DIN plugs with easier to solder cups?
If cups are oxidized, try cleaning them with a wire brush (small wire
brush in a Dremel tool) before soldering.

                                                Lee Jones

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