Gyrogami Blog - Precious Metals, Jewelry, Artwork

Aspect Ratio

Blog Index

Half Persian 3-in-1, AR 6.35
1/2" @ 2.0mm, 3/8" @ 1.5mm, 1/4" @ 1.0mm

Categories: Instruction and information; Jewelry

A comprehensive aspect ratio chart can be found here.

OK, not the most original topic but at least this one is useful. Well, maybe not that useful either because it's been covered before. Hundreds of times. This is just my way to add to the cyber babble.

Aspect ratio is the inner diameter of the ring divided by the wire diameter. It is both meaningful and completely useless at the same time. Without additional information, i.e. the ring size or the wire diameter, it is a number of unknown importance. That's why the same weave of a given AR can be different sizes. For example, all of the following have a 6.35 AR:

1/2" I.D. @ 2.0mm wire: 1/2" is 12.7mm, so 12.7 / 2.0 = 6.35
3/8" I.D. @ 1.5mm wire: 3/8" is 12.7mm, so 9.525 / 1.5 = 6.35
1/4" I.D. @ 1.0mm wire: 1/4" is 6.35mm, so 6.35 / 1.0 = 6.35

What's AR's purpose? To someone who is not familiar with chainmail or chain link designs, it's about as relevant as discussing quantum physics with a praying mantis. To maillers, it tells how the weave will look and behave. Of course, the measured (objective) size is critically important.

The wire and the dowel must be round for these calculations to work. While there may be a conversion chart somewhere for square-profile jump rings, I have not seen one. Depending on how rings lay in the weave, the flat edges of square wire can cause the rings to behave in strange ways. It may increase or decrease the required sizes in order for the weave to hold its shape.

With AR-sensitive weaves, there might be two ways to categorize them. The first group is totally dependent on AR. It requires a narrow range or it will not only not hold its shape, but it will undo itself (the rings won't fall out but it's called an unstable weave). That pigeonholes the size choices. Definitely not much room for experimenting. The second group looks best near a certain number but it will always remain stable.

In general, a lower aspect ratio produces a tighter, denser, and stronger weave. Go low enough and it will bind upon itself before becoming unweavable as there won't be enough space to weave the rings. Aside from the AR-sensitive weaves, there is no theoretical upper limit though spindly chains are not appealing.

The effects of AR show up under certain situations. All weaves have a 3-D structure, some more pronounced than others. This will be displayed most prominently when they hang. In a wide-ranging AR size run of the same weave, a few will collapse when laid down, indicating the AR is a bit high. Sometimes it looks OK but this should be known ahead of time to avoid surprises.

Even if you don't know much about chainmail, when someone mentions AR the next question should be, "What size are the rings?" The conversation should flow naturally at that point. End it before they figure out you only know three things about maille: AR, wire diameter, and ring size, lol.

A current loop-in-loop project of mine uses AR 36 and makes a weave so tight the entire 6" section can stand vertically. Another test piece used AR 44 for a thicker, equally as tight, still crazier yet, loop-in-loop. There are some ridiculous numbers out and about, but not usually.

It'd be interesting to see a Jens Pind Linkage JPL99. Using 3mm wire, the estimated 98-ish AR jump rings would be just under 12" diameter. To be comfortably stable and show it properly, figure 600 links. (Can it be stable this large? When will the rings be too weak to support themselves? Will it move or compact enough to finish the first iteration or start the second?) That means nearly 2000ft of wire, which is 90 regular pounds of 0.999 fine silver or 170 of 24k gold, standing as tall as a person. Now that would make one helluva necklace that even Mr. T couldn't wear!

Posted by M: August 23, 2019

Please email any thoughts or comments regarding this post.

Previous Entry . . . . Next Entry

Comment Section

NOTE: Your comments will be included in this section as long as they aren't illegal. This section is censor-free so show me your intelligence or ignorance and everything in between!

2024