Wire drawing is a process where metals and metal alloys are successively reduced in diameter by drawing through precision dies that, typically, are lined with carbide or diamond. Only a small reduction in diameter is achieved as the wire passes through each die. The exact amount is determined for each material and diameter to insure the integrity of the wire surface and metallurgical properties. The physical strength of the wire presents additional limitations. One can imagine that, for example, a 0.0006 Aluminum wire cannot endure much stress when being drawn down to 0.0005. In fact, a 0.0006 wire can endure only about a 5 gms of tension before breaking.
The dies have specially designed conical entry and flared exit surfaces that vary in angle depending on the material being drawn. Carbide dies do not have as good durability as diamond dies and do not hold tolerances as well. Diamond dies, however, are much more expensive than carbide dies.
Drawing Dies and Equipment
With an inventory of thousands of diamond dies, California Fine Wire can produce virtually any diameter desired between 0.0003 and 0.100. All wire is drawn using diamond dies that are maintained by California Fine Wire. In the Die Department, skilled craftsman assemble sets and polish dies to assure that the best dies are used to meet your requirements. The care and attention to dies enables production of high quality wire to the tightest dimensional tolerance available.
A Waterbury drawing machine and several others are used to reduce purchased wire to intermediate sizes for re-draw or, in some cases, to produce finished product. Purchased wire diameter can range from 0.100 to 0.020, depending on the type of material and finished product size. Fine wire drawing machines reduce wire from 0.010 to the smallest diameters manufactured, i.e. 0.0003.
Electrical Resistance Requirements
For applications that require a specific resistance, California Fine Wire can manufacture to the resistance value rather than the diameter. The standard resistance tolerance is +/- 3% of the nominal value and special tolerance can be as tight as +/- 1%.
Custom Redraw
California Fine Wire also performs custom redrawing of customer supplied material. Whether it is a material that is not in our inventory or an item that requires a special drawing process or handling, California Fine Wire can make it to your requirements.
Ultra Finish
Ultra Finish (.000025" out of round and ½ standard diameter tolerance) process is available for customers who require the best surface finish and the tightest diameter tolerance.
