The wire diameter is defined by the application - finer processes naturally employ thinner wires. Therefore. the capillary Hole is defined by the desired wire diameter.

Generally, thick wires are preferable due to their strength and better resistance to sweep during molding. However, there is a delicate balance between Hole and wire that needs to be observed in order to maintain the critical gap that allows the free and uninhibited movement of the wire. This critical gap is imperative for the success of the process and eliminating incidents of wire sway and wire friction.

Another factor influencing the wire diameter selection is the cost of the gold wire.