How long should a tig electrode stay sharp?

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Tig newbie practicing mild steel tig work (really like the cleanliness of tig vs mig working inside a painted hull) - and while I am now getting reasonable welds, the electrode just isn't lasting very long - I'd expected to go a couple days between sharpening, instead I'm resharpening 4-5 times a day - and not doing that much lineal welding/sharpening.1-1/2" mild steel angle iron (new material, pre-primed, primer ground off weld area), 3/16" thick, using 3/32"  lanthanated electrode, 130A DC, no pulse. Doing butt and corner welds.1) what causes the electrode to start balling on mild steel? - I've run a range of amps, and gone from 3/32" ceirated up to a 1/8" Lanathanated - and while the balling is significantly better with the Lanathanated, it's still balling too soon - and yes, the 1/8" balled too. - Does  contamination (electrode to puddle, filler to electrode) cause balling? Is it that simple?
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Reply:Originally Posted by nofacey- Does  contamination (electrode to puddle, filler to electrode) cause balling? Is it that simple?
Reply:When I first got my tig welder I was going about 5 minutes between sharpening, After a couple of hours I'm doing better.
Reply:Slight preflow of the gas improves arc starting and point erosion.2% thoriated is the best I have for holding a point on DC work. Although 2% thoriated is very good for DC, Lanthanated is not so good for me. Still either way I get no more than an hour out of my points on average, so I keep about 10 or so ready for swap out near my bench.Every once in a while I get a tungsten that goes all day. Probably because the slight erosion improved my arc profile somehow. Otherwise I still prefer needle sharp points.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:on carbon work, i always want needle sharp edge. buy more tungsten, sharpen all of them and replace often. a nice stock of sharpened tungsten makes the day go by alot easier. those shaky hand days come and go as they please. ps. clean it again anyways, can never be too cleanLast edited by sjmj1966; 07-06-2012 at 11:03 PM.
Reply:If I don't dip the tungsten (mandatory resharpen) I find that after a few hours the tip can use a refresh, which only takes a few seconds when you aren't grinding a brand new tip after dipping.
Reply:Sharpening 4-5 times a day sounds about right. You may consider using one size larger tungsten though this may have negative effects on performance.You're going to get a small ball point unless you're running, say, 3/64" tungsten at 25 amps. Having a small ball end doesn't affect arc stability much when you're working with thicker stuff. A lot of welders will deliberately create a very small "land" on the end of the point when sharpening. This reduces the likelihood that you'll spit the end off into the weld. That's no bueno.Yes, cleanliness can have an effect on electrode wear, that's a lot more pronounced when welding Aluminum with AC, I think. Tungsten has an odd property that tungsten oxides boil/evaporate at a lower temperature than the metal itself melts,The reason the ball forms is that the electromagnetic forces are highest at the very tip of the tungsten therefore the current density is greatest there.  Electrons tend to be attracted to sharp points, which is also the reason why lightning rods work.At my company If I need to sharpen I can walk 30 feet to the bench grinder.