You think the nonthoriated would be ground down? Every one I've ever seen has some evidence of aluminum weld to it. I'm off to try dropping them onto a workbench - DRE, how did you ever come up with that? Why 6 3/8ths?
I had some that were laser typed down the side in small letters see if you can find them , otherwise try the miller welding board they have guys over there that should help you
They say the Thoriated ones are slightly radioactive........knock two together and see if you get a mushroom cloud or use a geiger counter maybe......I'm really no help to you!
Thats why I never grind both ends of the electrodes. Sure it may save some time but it's not worth it. Been TIG welding since 1967 and never heard of the drop test, let us know how it works out.
I worked in the machine repair service industry and always talked to welders to pick their brains. More than once I was told that it was a termination offense to remove the color marking on a Tungsten electrode or use the end of a filler wire that had the alloy stamp. Some welding inspectors want the short ends with numbers left at the site for verification. I use 2% Lanthanated electrodes for everything and they work great.
Ok When I catch him I'll fire him, until then its hard to fire a guy who gives you a handful of them. I'm going to guess that where ever they came from couldn't figure it out either & that's why the had to leave
Pure tungsten will ball when welding aluminum on its own.thoriated will not. Find a real thick piece of aluminum ,set welder on ac with continuous high frequency and put it on its highest setting amp wise. Sharpen the tungsten to a point,if it balls real fast it's 100 percent pure,if it keeps the point or at least most of it ,2 percent or a hybrid thoriated type.
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