Postalloy® 306-FCO

Postalloy® 306-FCO is a medium carbon, high strength flux-cored, open-arc wire designed for butt, fillet and lap welding of low carbon and low alloy steels. Recommended for single and multi-pass welding applications in all positions. Use on steel thicknesses from 16 gauge up to 1/2" (12.7mm) thick maximum. When welding steels between 3/8"-1/2" (10mm-12.7mm) a preheat of 325-375 °F (163-190 °C ) is recommended. It is a versatile, easy to use welding wire with excellent operator appeal. Without the need for shielding gas, Postalloy® 306-FCO is ideal for welding applications in which the addition of gas is impractical, or where windy and other adverse conditions prevail. It is not recommended for low temperature applications.


Product Type

  • Flux-cored
  • Open-arc


  • Flux-core open arc maintenance wire used to weld I beams, channels, plates and pipes.

Weld Deposit Properties

Tensile Strength:
89,400 psi
Smooth arc action and low spatter
Ideal for high deposition requirements
Excellent out-of-position weldability

Welding Parameters

Current Type: DC Electrode Negative

Volts Amps Diameter Stick Out
Flat: 15-18 Flat: 100-225 .045" (1.2mm) Flat: 1/2" (12.7mm)
Vertical-up: 15-18 Vertical-up: 150-200 .045" (1.2mm) Vertical-up: 1/2" (12.7mm)
Overhead: 15-18 Overhead: 150-200 .045" (1.2mm) Overhead: 1/2" (12.7mm)
Flat: 17-19 Flat: 150-300 1/16" (1.6mm) Flat: 1/2"-3/4" (12.7-19mm)
Vertical-up: 17-19 Vertical-up: 150-250 1/16" (1.6mm) Vertical-up: 1/2"-3/4" (12.7-19mm)
Overhead: 17-19 Overhead: 150-250 1/16" (1.6mm) Overhead: 1/2"-3/4" (12.7-19mm)

Welding Procedure:

Packaging Options

Diameter Standard Packaging
.045" (1.2mm) 25 lb (11.30kgs) spool
1/16" (1.6mm) 25 lb (11.30kgs) spool