The point is, I did some major soldering back then and thought nothing of it. Those days we used silver sheet solder and cut tiny pieces to be used between two shapes. I do remember that solder will not fill in gaps, therefore the two pieces need to have a good connection. What I can't remember is how does one know when the solder has melted and flowed when you can't see it.
Luckily for me, I use paste solder and only on places where I can see it flow, like earring backs and now jump rings. The solder comes in a tube and has "flux" already in it. Flux is what makes the solder flow. When we soldered in class, we had to brush on the flux before placing the tiny piece of solder. The paste solder is applied with a "pick", which is a pointed tool.
Up until today, I had only soldered earring backs (a piece of cake.) Today I soldered jump rings closed. (Also, a piece of cake.) I have avoided doing it for so long out of fear I guess. So, I went to YouTube and found a demonstration. Geez...... how easy!
A lot of fancy tools are not needed; just a fire brick set on a cookie sheet, the solder and a torch. (I used my kitchen torch.) A very tiny bit of solder is needed for the seam of the jump ring. Apply heat to the jump ring for just a few seconds until it turns red and you see the solder flow. Then quench in a glass of water. It's that easy.
Afterwards, the piece will need to be set in some kind of pickling solution to remove the fire scale. But, that doesn't take much. I finished off four delicate chains today with soldered jump rings. They are all ready now for the clasp and a focal point.
Originally, I was doing this so I could solder a cross that a friend commissioned. I usually use "Snapeeze" jump rings in all my pieces as I really, really trust them to hold. But the chain in this piece was so delicate that I couldn't get the 4mm Snapeeze through the link. (Although, later on I was able to get it on the ends.) In the end, I didn't solder this piece at all.
Soldering can be daunting at times. But for what I do it is not. Time to quit putting things off out of fear.