Yeah, 3/8 12g will be a tighter weave than 7/16 12g. The term is "Aspect Ratio" or AR. It's the ratio between the ring diameter and the wire diameter, and it tells you how tight or loose a particular weave will appear, regardless of ring size. On the TRL shopping site, you'll see the AR value listed with the other ring specs. The rings in your source image look to have an AR somewhere between 4 and 5. If the lowermost belt is 1.25" to 1.5" wide, then the rings are about 3/8" to 7/16", and an AR of 4-5 puts you in the 14g - 12g range. This is just guessing based on personal experience. I'd recommend ordering a couple different sizes first and make a few test patches before putting in a large bulk order. If you want to skip that step, I'd vote for 12g 7/16".
How much coverage are you looking for? Are you going to overlap the maille in the front like the picture implies, or skip rings that would be covered? Are you continuing the rings up underneath the leather harness up top? Skipping the hidden rings will shave a few thousand off the count.
Getting the maille to hang like that is going to be a challenge. You'll need a trapezoidal panel to get the 12"-14" overlap up top and the 6"-8" gap at the bottom, and you're going to need to hide in a bunch of expansion to match the artists lines (the artist cheated :-) ). Also, if you use steel, the weight is going to make the skirt portion hug your legs. Aluminum or plastic rings have a better chance of flaring out with the jupon. How are you making the jupon?
Yes, annealing is what is meant by normalizing. You hold the steel maybe 50C above critical temp for long enough for the grain structure to refine. How long and at what temp depends upon the type and thickness of the metal. For something like 16 guage rings I wouldn't imagine that would be very long.
I'm still thinking about whether I want to use stainless or carbon steel.
I found a local company that does heat-treating, and I am going to ask them for a quote. If it's not too terribly expensive, I'd like to go that route, at least for my first piece, so I can learn how to do it properly.
I am also sure I can find a kiln I could use in the area, so that would be plan B. To be on the safe side, I may want to normalize the steel, as Rob mentioned. What would be the process for that? Would it be the same as hardening, but without quenching? Annealing, essentially?
Also, I am assuming that the piece will need to be supported on some kind of ceramic plate while it is removed and quenched so it doesn't deform under its own weight while the steel is hot and soft.
losthelm, thanks for the app recommendation. It looks like it is missing 1062, although it has a lot of information about 1060, which I assume is almost identical. It has a tiny blurb about 1064 as well.
Thank you once again for all the advice.
You can find a little research on heat treating that paticular alloy by downloading the heat treaters companion appl.
There is a decent chance someone in your area has a glass kiln for lampwork beads, fuseing, or slumping that maybe willing to help.
The kilns have a digital readout/controler and most are fairly easy to open the top, pull out the piece and dunk it in a bucket of vegtable oil.
Rhough you may have issues with some rings deforming under its own weight.