[sgtnoah]

Hope all of your weekends are getting off to a good start...

Jody's video about tungsten sharpening got me thinking about the optimal angle of sharpening for different situations. For steel, I don't have too many issues... If I'm running on the low end of the tungstens range, I'll lean toward a long sharp point. High end, short with possibly a more blunt point.

Aluminum is where I don't think I've hit the balance quite yet, T-Joints more specifically. You all gave me some advice a few weeks ago, and it has helped greatly. Now my joints are close to acceptable, but still seeming to need to run more heat than I would like to - to get it to melt up to the corner.

I can get a nice, shiny, rippled bead, using the following settings: 1/8" 6061 (2" wide strips), 3/32" tungsten, short tapered tip, 120 Hz, 75% Bal, 150 inital amps, 3/32" 4043 rod.

I have to move really fast, on the border of too fast (hard to keep the spacing even at times, and contaminating the tungsten way more frequently than I should). I know that practice will cure this, but I'd really like to slow things down a bit, keep penetrating to the root. I need the arc to push forward into the root, not cook the sides where I don't need any more heat.

I've had good luck winding the frequency up, but would like to know how to do it without going to extremes and leaning on my machines "fancy" settings. How do they do these joints with a traditional transformer machine? What else can I try?

Thank you much gents!

-- Pete

[MinnesotaDave]

Aluminum is where I don't think I've hit the balance quite yet, T-Joints more specifically. You all gave me some advice a few weeks ago, and it has helped greatly. Now my joints are close to acceptable, but still seeming to need to run more heat than I would like to - to get it to melt up to the corner.

I can get a nice, shiny, rippled bead, using the following settings: 1/8" 6061 (2" wide strips), 3/32" tungsten, short tapered tip, 120 Hz, 75% Bal, 150 inital amps, 3/32" 4043 rod.

I have to move really fast, on the border of too fast (hard to keep the spacing even at times, and contaminating the tungsten way more frequently than I should). I know that practice will cure this, but I'd really like to slow things down a bit, keep penetrating to the root. I need the arc to push forward into the root, not cook the sides where I don't need any more heat.

I've had good luck winding the frequency up, but would like to know how to do it without going to extremes and leaning on my machines "fancy" settings. How do they do these joints with a traditional transformer machine? What else can I try?

Thank you much gents!

-- Pete

I run a 1960's tig (my avatar) so frequency is fixed at 60 Hz, balance 50/50 only.
For 1/8" aluminum fillet I set my machine 200-230 amps (200 on flat stock, 230 for the square tubing we just did in a cold shop)
1/8" thoriated tungsten with short blunt taper and a flat spot (it will ball on its own while I weld)
I hit the pedal full to start, pedal it from there.
Power is your friend

As long as your feeding hand can keep pace, speed is not bad. Going too slow just cooks the piece anyway.
Last week I started my kid on tig aluminum and first thing I taught him is feeding the rod through his fingers on every dip and full pedal starts.

Edit: 2" strips are not very much mass. Cut them like two feet long so they don't overheat right away. If they overheat right away it can mess you up while you are learning.

[sgtnoah]

Dave,

Thanks for the thoughts, I'll give that a shot. I've been hitting it hard on starts, but not that hard. You are very right about heat building up in the metal. Starting to think that your hit it hard, weld fast, and be done before too much heat builds up makes a lot of sense.

On that topic, got me thinking about the differences between inverters and transformers… Correct me if I'm wrong here, since you have a fixed 50/50 balance, you are putting more of the heat into the tungsten (and less in the puddle) than I am running 75% EN. So my amps would be set lower than yours to get the same heat??? And along those deep thinking lines, I think that Jody said that lower frequency puts more heat in than higher frequency, so your welder at 60 Hz is putting in more heat than mine at 120 Hz

Just trying to compare your settings to mine and see how all the variables interact… Kind of neat to think about!

-- Pete

[MinnesotaDave]

Dave,

Thanks for the thoughts, I'll give that a shot. I've been hitting it hard on starts, but not that hard. You are very right about heat building up in the metal. Starting to think that your hit it hard, weld fast, and be done before too much heat builds up makes a lot of sense.

On that topic, got me thinking about the differences between inverters and transformers… Correct me if I'm wrong here, since you have a fixed 50/50 balance, you are putting more of the heat into the tungsten (and less in the puddle) than I am running 75% EN. So my amps would be set lower than yours to get the same heat??? And along those deep thinking lines, I think that Jody said that lower frequency puts more heat in than higher frequency, so your welder at 60 Hz is putting in more heat than mine at 120 Hz

Just trying to compare your settings to mine and see how all the variables interact… Kind of neat to think about!

-- Pete

Hmmm...seems you just explained that we are likely putting in about the same heat overall.
If I understand inverters correctly, yours would be deeper and more focused however.