Yes there is another way, whenever you strip wires always add a little solder to the wire ends or where you have to solder to before you even attempt to join the two ends together.Once both ends have a little solder then you can solder them together usually without adding any extra solder.
When doing soldering for audio I was taught that using too much solder isn’t a good thing and to just stick to the right amount and make it as tidy as possible, although our bike wiring is stressed by vibrations and the like.
Consider using nylon tie strips to make sure the wire is flush against something and doesn’t just dangle which in time would stress the weakest point.
sounds like you are melting the solder and putting it onto the wire, you should be heating the wire with the soldering iron then feeding the solder into the wire to melt it .The hot stranded cable should suck the melting solder deep into the strands. leave it to cool before moving it or dry joints can occur .
+1 with zeph11… you need to heat both parts being soldered with the iron, but in order to protect any delicate or heat sensitive components, a heat-shrink should be used. This is usually a metal item such as a crocodile clip placed between the soldered join and the next component. The heat shrink should dissipate the heat transmitted along the wire before reaching any components.
Er… did I miss the mention of “flux” somewhere? I think that’s the stage your probably missing out.
Once exposed to the open air, most metals pretty instantly take on a fine layer of oxide. Or they became oily during manufacture. Neither is going to help make a sound joint.
O.K. I know you can buy solder wire with a flux core but it’s pretty second hand fix sh*t.
Flux is an acidic etching liquid/paste that gets rid of the oxide/grease and allows the solder to bind to the metal, so flux both ends, tin both ends with solder, then holding both tinned ends together, melt the soldered ends together.
That’s the shorthand. For the full novel I’m sure there is a better description on line somewhere, probably with pictures.
Last. Read the directions on the back of the flux product. This is pretty evil stuff and needs some common sense in use.