Preparing Tungsten For Dc Electrode Negative (Dcen) Welding - Weldclass WeldForce WF-255MST Operating Instructions Manual

13.1.2 Preparing Tungsten for DC Electrode Negative (DCEN) Welding

The electrode should be pointed (tapered) according to the welding current.
Grind end of tungsten on fine grit, hard abrasive wheel before welding. Do not use wheel for other jobs
or tungsten can become contaminated causing lower weld quality.
Rule of thumb is that the taper section should be 2.5 times the Electrode Diameter.
Figure 69
Ideal Tungsten Preparation = Stable ARC
Diameter of the flat left on the end of the Electrode determines amperage capacity.
Figure 70
Wrong Tungsten Preparation = Wandering ARC
Figure 71
Pointing the Tungsten Electrode
The electrode should be pointed according to the welding current.
Figure 72
Electrode Angles
Angle @ Range of Current (Amps)
30° 0 – 30
60-90° 30 -120
90-120° 120 - 250
120° ≥250
Table 22