Welding Right Angles

[ratdude747]

Originally Posted by JamesCH95

Any benefit to pulling the tungsten into the nozzle? Maybe just to keep a new operator from dunking it in the puddle?

It always worked better for me. my guess is that it may have a "preheating" effect.

Originally Posted by JamesCH95

FWIW I prefer thoriated tungsten (Red, also radioactive! avoid unless you have vented grinding equipment!), lanthanated tungsten (orange), or zirconated tungsten (silver), over pure tungsten (green) for welding aluminum. Pure tungsten is a bit old-school and definitely not the best way to do it IMO as someone who earned an AWS welding certification in Al TIG.

I was always taught that the red and orange were for steel and green was for aluminum... whatever works for you... A lot of this is welder's preference

side note- thorium is not very radioactive... the high school shop where I learned to TIG didn't have vented grinders and we used red rods all the time... hopefully that won't cause problems down the road

Originally Posted by JamesCH95

Wire brushes, particularly non-stainless steel brushes, have a very nasty habit of making aluminum and other non-ferrous metals very dirty if used in weld prep. One must also ensure that stainless steel brushes are designated for one material only, i.e. aluminum, steel, or titanium, and that they are not used on a different material. I have always preferred abrasive sanding discs for aluminum weld prep because they don't contaminate the base metal, even if they're used on a different material. Though AC welding current (for AL) will break through the oxide layer as it is, and a break-arc technique will clean out even the toughest oxide deposits like anodized surfaces. Just be sure a good degreaser is used BEFORE and AFTER any brushing or abrasive prep.

I never did that... we used the same brushes used for everything... and I doubt they were stainless... I know, not good, but on a cheap public school budget...

[JamesCH95]

Originally Posted by ratdude747

It always worked better for me. my guess is that it may have a "preheating" effect.

It would force the arc to be longer, increasing the weld arc's work function energy, making the pool hotter. However, the longer arc is less stable and more heat can be added by turning up weld current, which is better in terms of arc control.

Originally Posted by ratdude747

I was always taught that the red and orange were for steel and green was for aluminum... whatever works for you... A lot of this is welder's preference

It's not just welder preference. The balled end of a pure tungsten electrode is molten and more likely to contaminate the weld with tungsten, particularly if the molten tungsten drips into the weld pool. This a REALLY bad problem if you want to do any post-weld machining, tungsten doesn't machine so well

The ground point on an red/orange/silver electrode control the arc better than the balled end on a pure tungsten electrode, and they can handle more heat/current.

[ratdude747]

Originally Posted by JamesCH95

It would force the arc to be longer, increasing the weld arc's work function energy, making the pool hotter. However, the longer arc is less stable and more heat can be added by turning up weld current, which is better in terms of arc control.



It's not just welder preference. The balled end of a pure tungsten electrode is molten and more likely to contaminate the weld with tungsten, particularly if the molten tungsten drips into the weld pool. This a REALLY bad problem if you want to do any post-weld machining, tungsten doesn't machine so well

The ground point on an red/orange/silver electrode control the arc better than the balled end on a pure tungsten electrode, and they can handle more heat/current.

well, since the shop had a large stock of really old stock electrodes, we used what we had first... all there was was red and green electrodes...

from what I have read green electrodes work well for AC AL TIG... FWIW, green rods are lower cost as well...