Richard.
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- Cambridgeshire
Yeah. Let the pool fully establish before going at it with filler. I can see on all 3 of those you've got fired into it prematurely causing that Nasty contamination at the start by melting filler across the arc rather than in the pool.So i've had a bash at the 3mm aluminium now too.
A couple of initial things that have surprised me:
1. Its so noisy compared to DC. Is that right?
2. It seems to take quite a long time to create the initial pool, its that right?
My initial attempts are abysmal. There's no getting away from it. I'm using the following settings:
Pre gas flow - 2secs
Ramp up - 2 secs
Current - 90-100amps
Ramp down - 2 secs
Post gas flow - 6 secs
AC frequency - 80-100Hz
AC Balance - 30%
Gas flow is still just using the standard regulator but i've upped the flow from 8 (steel) to 10.
Number 8 cup, 1.6mm white tungsten ground as per the alu TIG guide on here.
Initially the arc seems very focused/centered but it rapidly seems to grow to a point where its uncontrollable. Maybe i'm allowing the arc length to increase as a go? Each attempt seems to result in similar outcomes as per the picture.
Any thoughts?
Have a skim through this thread. There may be a few pointers in it that can help. http://www.mig-welding.co.uk/forum/threads/aluminium-tig-guide-getting-started.64695/