A Quick Guide to Wire Gauge and Hardness
Gauge refers to the thickness or diameter of the wire. The smaller the number the thicker the wire. For instance, to bend thick wire into a bangle, you might use 4 gauge, which is a little over ¼” thick. But if you want to knit with wire, you might use 28- or 30-gauge, which are almost like thread. Use a wire gauge tool by slipping the wire in a notch to determine the gauge.
Here are some common wire jewelry-making components and the best wire gauges to use:
- 12g-14g – heavier clasps
- 12g-18g – links, medium clasps
- 16g-20g – jump rings
- 18g-22g – ear wires, simple loops
- 20g-24g – coils, wrapped loops
- 24g-30g – knitting.
The hardness of the wire refers to the malleability. Hardness also differs by material. Sterling is harder than copper. Brass and bronze tend to be stiffer than both copper and sterling. When you’re working with very fine gauges, hardness is a bit irrelevant, since fine gauge wires are so thin they’re ultimately pliable.
But if you work with thicker gauges, you want to choose the hardness most appropriate for the work you’re doing. For instance, if you want to make ear wires, you know they should have some stiffness and spring to them. But if you’re coiling wire, you want that wire to be soft enough to easily wrap around whatever you’re using as a mandrel.
- Full hard: fully tempered, very hard and stiff. There is rarely a call for full hard in jewelry making
- Half hard: softer than full hard, but still holds some shape. Good for ear wires or hooks.
- Dead soft: very soft, no spring, very pliable. Best for bending, coiling, hammering, and manipulating the wire a lot.
Work hardening your wire
All metal becomes stiffer when you work with it–that’s called work hardening. Any sort of manipulation of the wire changes the molecular structure of it, causing it to become harder and more brittle. The only way you can return the wire to its softer state is to heat it, which you can do if you have a torch or a kiln. But you can always harden soft wire by hammering, either with a metal hammer to flatten and texture, or with a rawhide mallet, to maintain the roundness but temper, or harden, the metal.
You can use work hardening to your advantage when you’re making jewelry. When you start with soft wire and want to make a few jump rings by coiling the wire around a mandrel, the coiling will work harden the metal and make your jump rings stronger.
When you buy craft wire, it’s primarily copper with a colored coating of some type. Consequently it’s quite soft and easy to work with. Craft wire does not come in different degrees of hardness. But when you buy silver or copper wire from jewelry suppliers, you should specify the hardness you want.
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Is there a wire gauge you find indispensible? Share your tips and comments below!