Chainmaille Aspect Ratio, AR, plays a very important part in making maille, but it can be a tricky concept to grasp. AR is the ratio of the Inner Diameter of the ring, ID, to the Wire Diameter, WD. This ratio controls how tight or loose a weave is, or indeed whether the weave can be made at all.
All weaves have an AR below which the required connections cannot be made, as the weave becomes too tight to fit in subsequent rings. Most weaves do not have a maximum AR, but there will be a point where the weave becomes unattractively loose and floppy.
So you’ll see ‘recommended’ or ‘preferred’ AR’s for weaves that are pleasing to both the eyes and the hands.
Chainmaille Aspect Ratio Demystified
So let’s dive right in.
In this case we have a 16swg 5/16″ stainless steel ring. These numbers come right off of TRL’s product data, so this is what you’d be holding in your hand. The inner diameter of the ring is 0.335″, and the wire diameter is 0.062″. This means that the apect ratio of the ring is 0.335 / 0.062 = 5.7.
You can then check this number against tutorials to find out what weaves this ring size is good for. You can also use this number to find other ring sizes that will (or perhaps will not) work for a given weave.
In this case we have several ring sizes – 16swg 5/16″, 1/4″ and 3/16″, and 18swg 1/4″, 3/16″ and 5/32″. You can see that the inner diameter of each row gets smaller as you go from left to right, while the respective wire diameter stays the same.
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This means that the aspect ratio is getting smaller as you go from left to right. So any weaves you make with these rings will get tighter as you move from left to right; a weave that’s loose with 16swg 5/16″ might be perfect with 1/4″ and too tight with 3/16″.
A weave that’s perfect with 3/16″ might be too loose with 1/4″ and way too loose with 5/16″. This is partly an aesthetic choice and partly a practical one. You want to choose the aspect ratio that gives you the look you want.
So, if you’ve found a ring size that you like for a weave, where do you go from there? If you know the AR you can move to a larger or smaller gauge and know what inner diameter you need to achieve the same look as the original ring size.
In this example the 16swg 1/4″ ring has the same AR as the 18swg 3/16″ ring. This means that weaves made with 18swg 3/16″ will be ‘shrunk down’ versions of the same weaves made with 16swg 5/16″. They’ll have the same flexibility, same tightness, same everything.
This will hold for any two ring sizes that have the same AR. Even if the AR’s are slightly off they’ll still give similar weaves. The further away the two AR’s get the more dissimilar the weaves will be.
You might notice that even though the ring in the first picture is labeled as 5/16″ the inner diameter is not exactly equal to 5/16″ (0.3125″). This is because of springback, a property of ductile metals. Springback occurs when wire is coiled around a mandrel during manufacture of the rings.
When the end of the wire is snipped, the tension generated during the coiling process is released. The coil partially unwinds, or springs back, and the resulting inner diameter of the rings becomes slightly larger than the diameter of the mandrel on which the coil was wound.
It’s a pain to keep track of exact springback for every metal in every size, so most ring suppliers just list the mandrel size as the inner diameter of the ring.
In the vast majority of cases this is not a problem, as the amount of springback isn’t high enough to cause a big difference in how a weave looks and behaves. (A notable exception is Jens Pind, which is extremely picky about allowable AR’s.) So don’t worry if ring sizes you see don’t precisely match the AR, as it won’t make that much of a difference.
So there you go. Using aspect ratio to find new ring sizes is a simple but effective way to expand your creative arsenal.
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