Recommend ER4043 filler wire it has good ductility for an all around filler.
The 2000 series heat treated alloys are the most common. Common alloys are 2618-T61 or 2018-T61.
Alternating current is recommended for general-purpose work since it provides the half-cycle of cleaning action. When manual welding, the arc length should be kept short and equal to the diameter of the electrode. The tungsten electrode should not protrude too far beyond the end of the nozzle. The tungsten electrode should be kept clean. If it does accidentally touch the molten metal, it must be redressed. The shielding gases are argon, helium, or a mixture of the two. Argon is used at a lower flow rate. Helium increases penetration, but a higher flow rate is required.
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