Designing Chain Maille with Aspect Ratio

The aspect ratio (AR) of a jump ring is calculated by dividing the inner diameter (ID) of the ring by the wire size used to make it.

For example, a 19g AWG (1mm) ring with an ID of 3.25mm has an AR of 3.25.

AR = ID ÷ wire size

Knowing the AR allows you to substitute different ring sizes while maintaining a similar weave.

Using a larger AR will create a looser weave. A smaller AR will make the weave tighter.

Keeping the same AR gives the weave a similar look and feel, though the finished size will change. This lets you scale a pattern up or down.

For some complex patterns, the correct AR is essential to even make the weave work.

The ID of a ring can refer to the size of the mandrel it was made on-this is usually what you see when buying rings.

However, the actual ID measured with calipers can differ slightly, as metal springs back after winding.

In our example, the measured ID is 3.5mm instead of the 3.25mm mandrel size, making the actual AR 3.5.

The difference is small, and either measurement gives a good estimate.