First time tig welder and aluminium

[David Pye]

Hi guys,

I've been having a play with my new TIG (TecTig 206i) from Weldequip and have managed to lay reasonable-ish beads on thick steel (old brake discs) as a practice.

I'm using a 1.6mm tungsten (grey tip) and decided to have a shot at aluminium with absolutely no luck! Tried AC, 80% balance, and get a nice ball on the end of the tungsten, and can lay a reasonable shiny weld track as long as I don't try to add any filler.

Trying to add aluminium filler tends to melt the filler rod before it gets to the pool, and tends to leave a dull lump that refuses to melt into the weld pool properly even when I 'run it over' with the arc. Also, when adding filler rod I tend to get lots of soot/crud in the weld, whereas it looks beautiful if it's an autogenous bead.

I'd be very grateful for any suggestions!

Cheers,

David

 

[Omniata]

What sort of aluminium are you welding and what filler rod are you using?

 

[hotrodder]

Sounds like your 'angles of attack' are off with the wire and/or the torch, aluminium is fussier about this than steel because of it's low melting point. Soot/crud in this case sounds like it could be from the wire touching the arc, again lower melting point = more of a mess with ally than steel. Diagrams and more here... http://www.millerwelds.com/resources/improving-your-skills/tig/

If fixing the angles still results in dull/cruddy welds then you may be pulling wire back too much inbetween dips. Keep it too close and it melts, too far back and the hot end oxidises as it's outside of the argon

 

[shenion]

1. Slide the filler in low.
2. Keep a short arc length
3. Don't pull the filler out of the gas, that will contaminate it.

 

[weldequip]

Try a larger Tungsten too - 2.4mm (or 3.2mm on thick section)