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generated by the electrons impacting
the work piece than the atoms striking
the electrode .
ELECTRODE SHAPE
The electrode shape is a very important aspect to consider and has a significant impact when
welding various metals . The shape of the electrode will greatly affect the welding plasma
created during the arc . Poor electrode shape will lead to plasma arcs that are not repeatable
while good electrode shape will help the plasma arc to discharge smoothly from the welding tip .
The grinding direction to sharpen the electrode is very important . When grinding, make sure
that grind marks run parallel to the electrode shaft . Parallel grind marks will allow the plasma to
discharge uniformly and smoothly from the electrode . Grinding the electrode such that circular
rings or marks show up will lead to a poor plasma arc, affecting weld quality . The plasma will
discharge inconsistently from the electrode ridges and may become unstable, oscillating in
time . The weld spot will not be repeatable .
As a rule of thumb the electrode should be ground so that
the taper is approximately 2 .5x the diameter . The resulting
electrode shape is a good general shape for easy arc ignition
and excellent weld spots .
Always grind the welding electrode so that grind marks
run parallel to the electrode shaft . Placing the electrode
incorrectly on the diamond wheel will produce circular grind
marks and poor weld results .
Good
Bad
Material
Melting Point (deg C)
Zinc
420
Aluminum
660
Silver
962
Gold
1064
Copper
1083
Stainless 304
1450
Carbon Steel
1500
Titanium
1660
Platinum
1772
Niobium
2468
Tungsten
3410