How to Grind and Prepare a Tungsten Electrode
A correctly ground tip is the cheapest arc-stability upgrade there is. Here is how to prepare each electrode type — and how to do it safely.
Tip shape by current type
| Electrode | Current | Tip shape | Why |
|---|---|---|---|
| WP (green) | AC | Balled | The AC half-cycle forms the ball naturally and the ball stabilizes the arc |
| WZ8 (brown) | AC | Balled | Holds a stable rounded ball at high AC current |
| WT20 (red) | DCEN | Truncated cone | Keeps a sharp, focused tip with low burn-off |
| WC20 (grey) | DCEN | Truncated cone | Easy starting at low current with a fine point |
| WL15 / WL20 (blue) | DCEN (& AC) | Truncated cone | Long-lasting point with a stable, well-defined arc |
| WY20 (white) | DCEN | Truncated cone | Concentrated arc for precision work |
Grinding angle and direction
For DC work, grind a taper of roughly 20–30° included angle (about 2–2.5× the electrode diameter in length). A sharper point is easier to start but erodes faster; a blunter, truncated tip gives a stiffer, more penetrating arc.
Always grind lengthwise, with the axis of the electrode — never crosswise around it. Circumferential grind marks make the arc scatter around the tip instead of sitting on its point. Use a dedicated fine-grit wheel reserved for tungsten to avoid contaminating the tip with other metals.
Safety notes — especially for thoriated
- WT20 contains thorium oxide: wear a respirator and use dust extraction when grinding it, and dispose of grinding dust per local rules.
- Ceriated, lanthanated, zirconiated and yttriated electrodes are non-radioactive — normal eye protection and a dedicated wheel are sufficient.
- Let the electrode cool before handling; hot tungsten is fragile and snaps easily in the collet.
Prepared tips from the factory
Our electrodes are supplied ground and cleaned with a flat tip; specific tip preparation — pointed, truncated or balled — can be arranged before shipment, useful for robotic lines where consistency matters. Ask with your quotation.