Round Wire
Round Wire
The default wire profile of the bench, drawn through round dies in graded gauges
Round wire is wire with a circular cross-section, the most common wire profile in jewellery making. It is produced by drawing metal stock through progressively smaller round dies until the desired diameter is reached. Round wire is supplied in precious and base metals across a wide range of gauges, and is the standard form for chain-making, prong construction, jump rings, ear wires, and the majority of findings used at the bench.
Production
Wire drawing begins with cast or extruded rod, typically several millimetres in diameter. The rod is drawn through a tungsten-carbide or diamond die whose orifice is slightly smaller than the rod. The metal flows through the die under tension, reducing in diameter and increasing in length. Successive passes through smaller dies reduce the wire to the working gauge. Between passes the wire is annealed to restore ductility, since drawing work-hardens the metal.
Modern bench wire is supplied either dead-soft (fully annealed and ductile) or in graded tempers from quarter-hard through full-hard, depending on the application. Soft wire is preferred for forming, wrapping, and operations where the wire must conform to a shape; hardened wire is preferred for prongs, ear wires, and structural elements that must resist deformation in wear.
Gauges and standardisation
Round wire is sold by gauge or by metric diameter. The Brown & Sharpe (B&S) gauge, also called American Wire Gauge, is the dominant system in North American jewellery; it runs in inverse relation to diameter, with smaller numbers denoting heavier wire. Common bench gauges run from about 6 B&S (4.1 mm) for heavy bezel and structural stock down to 30 B&S (0.25 mm) for the finest filigree and chain.
European and Asian suppliers typically use millimetre diameter directly. Stepped sizing — 0.25, 0.30, 0.40, 0.50, 0.60, 0.80, 1.00, 1.20 mm and so on — is standard. Conversion between B&S and millimetre is straightforward and is tabulated in every bench reference.
Alloys
Round wire is supplied in fine silver, sterling silver, Argentium silver, brass, copper, gold-filled, and across the gold karatages from 9 ct through 24 ct in yellow, white, rose, and green colours. Platinum and palladium round wire are available but command substantial premiums and are typically purchased only as needed for specific commissions. Each alloy has different drawing characteristics: high-karat gold draws easily and remains soft after annealing; sterling silver work-hardens rapidly and requires frequent annealing during fabrication.
For findings and chain-making, the alloy is chosen to match the metal of the surrounding piece. Mismatched alloys produce visible colour differences and can cause electrochemical corrosion at the joint over time.
Use at the bench
Round wire is the standard stock for jump rings, head pins, eye pins, ear wires, prong stock, and the wire elements of chains and findings. Heavier gauges (12-18 B&S, 0.8-2.0 mm) are used for ring shanks, bracelet stock, and bezel construction. Medium gauges (20-24 B&S, 0.5-0.8 mm) are used for ear wires, light prongs, and chain links. Fine gauges (26-30 B&S, 0.25-0.40 mm) are used for filigree, fine chain, and decorative wirework.
Round wire is preferred over square or rectangular stock for any application requiring smooth wrapping or curving. Square wire is preferred where a flat face is needed for bezel construction or where the wire is to be soldered against another flat element; round wire's curved surface complicates these joints. For most bench operations, however, the round profile is the default and the alternative profiles are specialised.
Drawing at the bench
Bench jewellers maintain a draw plate — a hardened steel plate pierced with a graded series of round holes — for finishing wire to specific diameters and for hardening wire by drawing without annealing. A short length of wire is filed to a taper at one end, threaded through a hole, and pulled with draw tongs through successively smaller holes until the target gauge is reached. Drawing also straightens wire and produces a clean, uniform surface; bench-drawn wire is preferable to as-supplied wire for fine visible work.
In the workshop
Every bench jeweller stocks round wire in a graded set of gauges in the metals they work most. A typical bench inventory in sterling silver and one or two karatages of gold runs from about 12 B&S down to 26 or 28 B&S in 100 mm to 1 m lengths, supplemented by jump-ring coils and findings stock. The total inventory cost is modest in silver and substantial in gold, and the rotation of stock is one of the principal capital decisions of a working studio.