Transformer type machines on AC are the most demanding on tungsten electrodes. This is because the AC balance and frequency are fixed, 60Hz or sixty cycles per second. I wanted to put the E3 to the test by welding about 85 feet of 1/8" aluminum. The fuel tanks I welded were corner to corner to make fillet welds.
I sharpened the tungsten to a point and then tapped it on the grinding wheel, putting about a .030" flat spot on it.
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| Radnor's E3 tungsten, 3/32" |
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The first thing I noticed was the ease of arc starting, sometimes with the older machines the mechanical high frequency causes problems. This tungsten minimized this problem, fewer than 10 out of 300 times I had to double tap to start the arc. The most noticeable advantage was the size of the ball at the tip. It was slightly smaller than the diameter of the tungsten, which as you know allows for a tighter arc and a smaller weld. Compare that to the 2%Th which creates a ball almost 2X the diameter.
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| 2%Th at the top. E3 on the bottom. After 85' of weld at approximately 150 amps. |
In conclusion: If you're still using a transformer machine, switch to E3 now! There are zero advantages to using traditional 2%Th, even the cost. Not to mention the there is no risk of radiation. Try em, you definitely will like them. Also, I didn't get paid to say that.
Next I'm going to try them with an inverter machine on both DC and AC
