200 DX Hard starting arc and burning Tung

[TJS]

My 200DX is fairly new to me. I had a 180SD. I have 1.5% (golds).
Here is what I was doing:

Tungsten: Gold 1.5% 3/32 w/#7 Cup sharpended with a .030 flat
Material: .090 6061 wire brushed and acetoned
Rod: 4043
Amp: 90
Balance 45
Freq. 90hz
Gas: pure Argon with 15-18cf
Torch: WK #17


I was welding a Canton coolant tank for a 2001 Supercharged Mustang. I had to cut a notch in it and make 2 pieces to fit in place to clear the blower.I practiced on some material first to get my settings. The first weld it would strike an arc right away. The second time it would not. It would just bzzt bzzt and then I would have to take the tungsten out and grind it again. After grinding I only got about 2 to 3inches of weld out of it. As I am writing this I think my post-flow time is too low causing a pre-mature burn. I got the project done, but it took me a while. More filing and fitting than anything else. Man I gotta tell you if you have ever seen Canton items that are TIG welded (alum), they are perfect and it looks like a machine does this and not a human. Sorry so long.
T.J.
www.tjsperformance.com

[Scott V]

I know this does not matter on the start but don't you think bumping up the
electrode - part to #30 would be better?

I never used a Dynasty but a Thermal-arc has hot start tig setting that really helps the arc starts.

[Bob Sigmon]

I would think that the balance needs to be 65 -75. You are running all the heat in the tungsten and reducing your penetration. I've never run below 70, but I haven't been welding all that long. I also run the frequency at 100hz. For 16ga aluminum, I've run the frequency as high as 200hz (trying to keep the arc focused for a smaller bead).

Just my meager experience, but it works.

[Blown S-10]

balance 45 :eek: :eek: :eek:

try 65-70.

i wouldn't trust a weld at 45.

[Paul Seaman]

My D200DX doesn't get enough cleaning action until I go down near 50-55.

[HAWK]

Do turn up the balance unless your aluminum is just plain trash. My guess is your perimeter cleaning area is 1/4" or larger. Try keeping the white outside line surrounding the weld bead between 1/8"-3/16". This shows good cleaning action.

At 45% balance you are concentrating the majority of the heat into the tungsten electrode. This causes premature meltdown and frosting of the tungsten. Running such a high EP balance will require a higher post flow time. If you scratch the tungsten tip against the Al work surface it will remove the frosting and make the arc easy to strike.

90HZ is a tighter arc than a transformer machine, but is still has a wide arc cone. Arc frequency depends on joint design and operator technique. It is probably not a large factor in this case.

If you must run a high electrode positive balance, then a + polarity and higher than normal starting amperage may need to be set within the machine's hidden menu. This will help your arc starts tremendously.

[TJS]

thanks for the repys. I was trying to copy the kinda flat and fairly wide bead of what Canton did, thus I needed a wide cone arc. I will set the bal. higher next time. I am still learning with this machine and have to stop saying to myself "well I used this xxx setting on my 180 so it should work for the Dynasty" this theory does not work. When I was practicing to weld this coolant jug I had the amps on 110 and it was way too hot causing everything to "sink". If I had the 180sd I know 110 amps would be good. I had to then set the DX colder to get a puddle that would not "sink".Looks like more practice and machine setting practice. Thanks again.
T.J.

[Bob Sigmon]

TJS,

Just a thought, is there any contamination on the tungsten above the ground tip? That will cause some problems with the start and the arc.