Radnor E3 Tungsten

[Steve]

I just had a chance to use the new Radnor E3 tungsten after using 2% lanthanated almost exclusively for a while now.

The E3 is not radioactive and can be used for ac & dc and works well with all metals.

So far, the E3 tungsten keeps a point even with ac and is really smooth. It seems to last longer and the end does not ball up as quickly when using ac. Arc start is smoother than standard lanthanated. I've been welding a lot of aluminum lately and this new E3 is going to be my main tungsten. DC is really sweet and smooth.

The cost is about the same as other tungsten and so far is only available at AirGas.

I recommend trying this new tungsten. It may change your mind about tungsten.

[performance]

The radiation from Thoriated is very mild indeed. It's an alpha emitter which won't penetrate the skin.

[Paul Moir]

I'm no health physicist but...

I wouldn't be so cavalier about the alpha radiation you get from thorium. The thing is, it's a big ol' helium ion flying out when thorium decays. It's so big, it won't go through your (dead) skin. However, once it's inside you, that big ol' wrecking ball can hit something important (alive), and do some serious damage. That is to say, once inside you it may be worse than other forms of radiation.

I think reasonable precautions are plenty (don't eat it!) but I'm waiting for the day they restrict it's use for welding food equipment. I'm surprised no one seems to have thought of it yet.

[performance]

Thoriated tungsten, it is actually the very center that is radioactive, a narrow shaft of it running down the middle, not an alloy like you'd think. In fact the tungsten itself, would probably limit most of the radiation. There is more radiation from a Swiss army watch with a phosphorescent dial, or a cell phone or the sun. They ship this stuff by mail. Apparently it doesn't trigger any sensors in the post office.

[Paul Moir]

Oh yeah, don't worry; I'm not that guy.

I just wanted to point out the big difference between it outside of you and inside of you. Alpha particles are easily blocked (paper works just fine) but once inside you this works against you. Instead of crappy old paper getting bombarded, it's your DNA. I think you're right: it isn't much, and there are bigger hazards like bananas. But sniffing your grinder dust isn't a great idea.

That's interesting about the construction of thorated tungsten. I had thought it was an alloy.

(PS - I previously said "Helium ion" where I should have said "Helium nucleus". If helium ions were a problem, we all wouldn't be doing so well welding with it! )

[3m-11]

It's not so much the thoriated electrodes that are potentially dangerous - it's the dust that comes from grinding these electrodes. Users inhale the dust into their lungs where it sits exposing tissue in very close proximity.

Female factory workers who wound up with radiation poisoning and osteonecrosis of the jaw from licking radium-paint tipped brushes while painting watch dials didn't get their illness from handling the glowing watches; they had to ingest the radium paint. Although the level of radiation produced by thorium is many orders of magnitude less, and thorium is _much_ less dangerous than radium, it would be prudent to exercise care re: inhaling dust produced during the sharpening of thoriated electrodes. Especially if there's a possibility of long-term exposure involved.

3M-11