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Byzantine is the most popular and recognized weave in chainmail jewelry. There are numerous places on the internet to find patterns, but most people have a hard time determining what size to wear and how many rings they will need. It doesn’t help that many of the oldest patterns were written a long time ago when chain makers used to make their own rings using the cut shank of a screwdriver or a wooden dowel that actually shrank a little each time it was used. They would then place their ring on a ruler and choose the closest fraction as the size.
Today the rings are made with a little more precision. Specialized mandrels are machine ground to exact millimeters. Digital calipers will give you an accurate reading. High quality saw cut rings are sold by the troy ounce in hundreds of sizes. So many sizes, in fact, that beginners are routinely confused by all the options, especially if they’re trying to convert the fractional inches your pattern requires to the millimeter sizes most chain mail ring companies use.
After much testing, the ideal sizes for Byzantine weaving were determined. Once you decide what gauge of wire you want to work with, you can select the correct ring size, based on these recommendations. But how many to buy? To answer that, you need a few more pieces of information, one that only you can provide: How long do you want your chain? The next step in the formula is “How many rings do you need to weave an inch of chain”? To figure this out, you have to weave an inch of chain and then count them. Fortunately, this step has already been done for you.
So now we’re down to simple math. The ideal ring size for Byzantine in 22 gauge is 2.25mm inside diameter and you need 40 rings to make one inch of chain. If you want a 20-inch necklace, the formula would look like this: 20 (inches of chain) x 40 (rings per inch (rpi)) = 800 rings of 22ga/2.25mm.
To go up a gauge to 20, the ideal ring size is 2.75mm id and rpi is 33. Again, I’m using a 20-inch chain as an example. 20 x 33 = 660 rings of 20ga/2.75mm.
If you want to use 18 gauge wire, you will need to order 3.5mm inner diameter rings and you will need 26 rings per inch. 20 x 26 = 520 rings of 18ga/3.5mm.
The most popular wire size for Byzantine is 16 gauge and the 4.5mm inner diameter is the perfect ring size. In this size, you need 20 rings per inch: 20 (chain length) x 20 (rings per inch) = 400 rings of 16ga/4.5mm.
Using 14 gauge wire, it can move rings up to 5.5mm inside diameter and 16 rings per inch. 20 x 16 = 320 14/5.5mm gauge rings.
Please note that this does not take into account the length of the closure. You should measure it and subtract that number from the length of your chain. Or leave it with a margin of error in case you lose a ring or two.