why no ballin

by julian twigden
(england)

its been about 6 yrs since i did any tig welding aluminium. my question is - why when im welding and when ive finished welding does the tip of the electrode not form a nice round ball.its got what i would describe as a bumpy nodule not a ball on the end. what am i doing wrong?have i got too much gas flow? or the angle of the torch? or i havent got enough stick out of the electrode? also.ive read that about the best electrode for both ac and dc is 2% lanthanated. i honestly thought that the only electrode to use on ac was zirconiated electrodes.is it right what i read.

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things are changing. the reason for the confusion is inverters.

inverter tig machines work better with thor, cer, or lanth.

used to be that pure or zirconiated was recommended...not so much anymore.

zirconiated works ok, i like 2% lanth better because I can use one electrode for everything.

if you want a pretty ball, set machine to dcep and use just enough amps to round the tip of the electrode.

then set the machine back to ac for welding and the tip will stay round unless you exceed the amp carrying limit for the diameter of electrode used.