I use a lot of jump rings as bails, either soldered onto the back of a pendant or — more often lately — linked through the pendant. I solder all of the jump rings closed. This is a little easier to do if the ring will be soldered onto something later, since you can lay the circle of wire flat on the soldering block: there's less of a chance it will melt since the whole thing is evenly protected by the block.
[Note that there are many different ways to solder a ring of metal, whether it's a jump ring, a finger-sized ring, a bezel wall, or whatever. One of the current instructors at the Art Center holds a ring in a tweezers locked in a third hand: the tweezers draws some of the heat away...or something...and this is good...or so it seems. Except that I didn't learn to solder rings that way, and my first few attempts didn't seem easier (change is always hard!), and I haven't spent the time to practice the technique. So I solder single rings flat on a block.]
When you're soldering a jump ring "in place," the ring is looped through another piece of metal, and the two ends to be joined are sticking up in the air — as far from the metal as possible, so solder isn't likely to jump to it, and thus the ring is almost totally exposed. Read: easily melted.
The other day I was finally finishing up some fish I'd made a few years ago, with something completely different (now mostly forgotten) in mind. Since they'd been sitting so long (and I still like them) I decided to solder bails on them and string them as pendants. The thing is, I chose to use thinner, bigger jump rings than I'd been using lately, and disaster struck.
Lately, usually — and let me first say that all measurements are approximate, but I just sat with all three jump rings and a ruler, so theoretically the data should be, you know, useful enough for comparison. So, lately I've been using jump rings that are either 1/8" inner diameter (3mm) 20 gauge, or 3/16" inner diameter (4mm) 18 gauge. The first is thinner wire and a smaller circle, the second is thicker wire and a bigger circle.
The jump rings I chose for the fish (why? you ask. Because the other two jump rings were too small, and mostly because I had these on hand) were 7/32" inner diameter (5mm) 20 gauge: the thinner wire and an even bigger circle. Out of practice with this size and with half of it sticking up in the air, it was really easy to melt these while trying to solder them together, and
melt them I did! I managed to solder four jump rings, but I also melted four (maybe five) others.
The thing is, when I worked on the jump rings for the next three or four fish, I only melted one or two. Practice really does help, whether you're completely new to a technique, or you simply haven't used a particular size of jump ring since you threw together a delicate chain two years ago to wear to a fancy dinner.
I always tell students the best way to
get over the fear of melting things with a blow torch learn to solder is to make a chain: you're working on very small things, so you're gonna melt some, get over it! And you're using a lot of them, so there's lots of practice. Obviously, making a chain means you're working with small objects. This won't help you learn how to solder really big things together. But it will help you learn how to solder, and get over some of your fear of melting things.