Aspect Ratio - This is how it really works!

Aspect Ratio is a very simple equation that allows you, the designer,
to choose the density of your work. Do you want an open and airy version of the Byzantine Link
or do youlike the look of a really tightly woven Full Persian? The following information will guide
you in the correctchoice of wire gauge and inside diameter of your jump rings.

Jump rings sold today are sized two ways.
The first measurement given is the I.D. or Inside Diameter.
This is the size of the mandrel that the links are wound on.
That measurement is usually given in millimeters.

The second measurement given is the gauge of the wire.
In the United States, the American Wire Gauge scale,
commonly referred to as AWG, measures all wire
(it is also known as the B&S or Brown and Sharpe).

To find the Aspect Ratio of any jump ring, these two measurements need to
be converted to the same measuring scale.
My preference is to convert the MM and the Wire Gauge into inches.

Let's break down the conversion:

A 5mm mandrel converted from millimeters is equal to 0.196"

16 gauge wire converts to 0.050"

Now all we have to do is divide the MM size by the wire gauge size.

(5mm) 0.196" divided by (16 gauge) 0.050"= 3.92

The Aspect Ratio of a 5mm I.D. 16 gauge jump ring is 3.92.

There are many patterns that require a basic understanding of A.R
One of the most prominent of these links is the Jens Pind.

There are two sizes that I love to use for this weave.

6mm I.D. 12 gauge wire.   - .236" divided by .080"= 2.95

4.5mm I.D. 14 gauge wire - .177" divided by .064"= 2.76

As you can see, these are similar and very tight Aspect Ratios.
Each link in the Jens Pind has to hold three rings snugly with just enough movement.
If the rings on this link are too loose the pattern will not hold and if the A.R.
is too small the pattern will be stiff and won't flow.

So, this should all make perfect sense now, right?
Now here is the catch.
All of these numbers are rather fluid.
The aspect ratio figures are a gauge to start working from.
When sterling or even fine silver wire is wound onto a mandrel
it tends to spring back and the I.D. is actually larger than the mandrel size.
Use these numbers as a guide, not an absolute.

I.A.R. = Ideal Aspect Ratio: Ideally, the inside diameter of a ring is equivalent to the size of the mandrel.

A.A.R. = Actual Aspect Ratio: A.A.R. is determined if you take into account springback from coiling.



Copyright © 2014, Anne Mitchell