Pure & Zirconiated, Why Not?

[redbeard]

I see in the manual that Everlast doesn't recommend pure or zirconiated tungsten for inverter welders, and was wondering why not. Please explain.

[Grizzly1944]

Read this:

http://www.weldingtipsandtricks.com/...odes-gtaw.html

This might shine some light. Basically they are both junk and not worth the trouble. Especially with an inverter type welder.

[jakeru]

When I tired zirconiated on my Super200P, the main thing I disliked about it (compared to lanthanated or ceriated) was how much relatively harder the arc was to start.

The 250EXT such as you've got however, supposedly has a new and improved arc starting mechanism than other Everlast inverter welders have, (so I do wonder if it would start an arc with a zirconiated or pure electrode much more easily than the rest?)

The zirconiated tip much more readily melts (forming a "ball" or hemispherically shaped liquid/melted tip) for a given amount of current, compared to lanthanated/ceriated/thoriated. For a given arc length, a balled or hemispherically shaped tip spreads the arc out much more widely than a "sharp" tip does. There may be some scenarios where the balled tip gives "better" results, but IMO probably for most AC TIG welding scenarios, (and for all DC welding scenarios it's pretty much undisputed), that a sharper tip is more desirable.

Basically, if you are running zirconiated or pure, you should probably expect your tip to melt and form a hemispherical shape; whereas if you are running ceriated/lanthanated/thoriated, it's best to try to *not* run it so hot that the tip melts into a big ball.

[performance]

Those tungstens typically will not hold a point and will ball under normal inverter use and the arc will be come unstable and erratic. Think of it, the arc can jump anywhere it wants to on the surface on the ball, on a point it will only jump from one spot unless it is contaminated.

[CGCINC]

I use Pure for AC Aluminum welding with my 250X, I know you guys all say NO to that but it works very well for me. It keeps a very tight ball the size of the Tungsten on the end and is really smooth.
I have tried Thoriated but I get small splits in the tip and little balls on the end and sometimes it will "spit" Tungsten into the weld.

I haven't tried any other Tungsten since these are what I use at night school as well, But I do plan on doing a more indepth test of my own with different Tungstens.
I think alot of it comes down to fine tuning the welder for the Tungsten your using...

[performance]

I use Pure for AC Aluminum welding with my 250X, I know you guys all say NO to that but it works very well for me. It keeps a very tight ball the size of the Tungsten on the end and is really smooth.
I have tried Thoriated but I get small splits in the tip and little balls on the end and sometimes it will "spit" Tungsten into the weld.

I haven't tried any other Tungsten since these are what I use at night school as well, But I do plan on doing a more indepth test of my own with different Tungstens.
I think alot of it comes down to fine tuning the welder for the Tungsten your using...

That's because you have too much EP on it. Turn it down to 30%.

[redbeard]

I guess What I should have asked is what difference it makes whether the machine is an inverter or not. Is it sine wave vs. square? Why would that make a difference in balling up?

I'm not really interested in pure since it goes away so quickly, but the CK cheat sheet recommends zirc for low amperage AC, which is where I would eventually like to head with this.

[performance]

Adjustable cleaning action. A point is nearly always preferred to increase penetration, reduce cleaning lines, and improve arc directability.

Pure Zirc is for Transformers as well, not inverters.

With a inverter you are do not have to use a balled tungsten as you do with a transformer. That is the whole point. (no pun intended)

[CGCINC]

With a inverter you are do not have to use a balled tungsten as you do with a transformer. That is the whole point. (no pun intended)

Then I need to go back to the drawing board!! :}
My Instructor said you always want a balled end when welding Aluminum..... Of course his "Instructing" ability leaves Very much to be desired.

[performance]

Yes,
If he has only worked transformers, then that is true...but not inverters. You can tell him the Everlast Guy said he was wrong...Then tell him Miller does too: http://www.millerwelds.com/pdf/DynastyQuickRef.pdf

[redbeard]

Thanks Mark, I think the light bulb finally came on!

That is a nice cheat sheet, only 2 pages and in color, I like it much more than the one from CK.

[CGCINC]

Yes,
If he has only worked transformers, then that is true...but not inverters. You can tell him the Everlast Guy said he was wrong...Then tell him Miller does too: http://www.millerwelds.com/pdf/DynastyQuickRef.pdf

Hmmm.. Time to go shopping..... Thanks for the link!

[GUNNER]

Why bother with those other types when the red is the cheapest and the one most recommended? I was thrilled it didn't require rare earth or some other expensive type..

[jakeru]

Why bother with those other types

To avoid the risk of breathing in radioactive dust (when grinding them to sharpen.) Also, if you order them online and shop around, tungstens aren't really that expensive. I like buying mine from diamond ground. Finally, there is no performance drawback to using alternatives to thoriated. In fact, in many tests, the newer alternatives actually outperform thoriated (e.g., 2% lanthanted test on weldingtipsandtricks, linked to in the post #2 of this thread, outperforms all others in holding a point under heavy AC current.)