Welding .016 annealed stainless

[zach]

I am welding .016 annealed stainless. Looking for some tips on filling in holes left behind after fusion welded. I use a copper fixture with backing purge plate. Using a dynasty 700 set on 30 amps (no pulse when filling) not using all the pedal, until filler rod builds up. The lowest amps I can get the arc to initiate is 5(can't use lift arc in fear of tungsten inclusion) , so I usually start the arc on the weld fixture then let off the pedal to the least amps (maintaining arc) and move to the material. The problem I am having when filling the holes is that I end up chasing the hole perpendicular to the weld ,making a 1/8th inch wide intial fusion weld 1/4 inch in repaired areas. I think i am not giving it enough amps to draw the seperated material back together, in fear that to many amps will blow the material away, causing a larger hole. I try to add filler rod (.040 ER308L)to all sides of the hole before filling, but usaully end up chasing. Lookin for any tips,tricks,advise or whatever I can get. I do know the best way is not to blow holes to begin with, but the holes are produced by variables of excessive gap in fit up (.006 or greater),material and machine welded(manually repaired). Thanks again for any advice.

[dave powelson]

.020 tungsten ?

I read the manual and made a few changes. I got the start arc turned down to 5 amps , It was on 30 amps. Went from using .063 2% thoriated to .040(much better). The manual says .020 tunsten for 15-40 amps? Would it be better?
Thanks for the advise it is all greatly appretiated. I am a welder that is proud about all my welds, until I was humbled buy this material. Annealed welds different than the normal hardness .016 ss.

You'll need to try it yourself. Depending on what you want to see for the arc and how the arc 'drives' (as I call it), one size may 'drive' better for a setup than another.
What electric4life sez on point angle and configuration (like slight blunt on tip) helps. Going even higher on the included angle spreads arc as well.

For what it's worth (repeating myself again)--for manual setups, the slow pulse (and you can tailor the pulse characteristics) allows time for the puddle to cool, etc.---compared to the fast pulse.
I always slow pulse or peddle pulse on OHH! TOO! THIN!

If you haven't played with the pulsing, you're missing an opportunity to make yourself look better--than you really are!
....that's 'why?' we spend all that money on the dynasty's zoo of bells and whistles....to make us look much better than we actually are!

Starting on p. 56 of owners manual showing and explaining how to tailor the arc start further when in the tungsten 'GEN' setting mode. You can turn that start down more.

[zach]

.016 annealed ss

I read the manual and made a few changes. I got the start arc turned down to 5 amps , It was on 30 amps. Went from using .063 2% thoriated to .040(much better). The manual says .020 tunsten for 15-40 amps? Would it be better?
Thanks for the advise it is all greatly appretiated. I am a welder that is proud about all my welds, until I was humbled buy this material. Annealed welds different than the normal hardness .016 ss.

[Electric4Life]

Controlling the temp is key. Balance the 3.
Tungsten, Filler and Base Metal (for thin applications)
Gas flow is last but not least in control, but that is after arc is struck and your fine tuning.
Sounds as though the material is giving away far sooner than your able to add the filler due to such a difference in melting temperatures. In other words, the filler rod is TWICE the thickness of the base metal. Controlling temp between two vastly different thicknesses is tricky, and it's amplified the smaller you go


Try this if You havn't already...
.040 1.5% Lanthanated+.035 ER309L
Sharpen that thing with a 15 degree point, lessens penetration, keeps heat shallow. Lay the torch over to "reflect" the arc off the surface.

Good luck

[dave powelson]

repairing open gap .016 SS welds

I'd first question if the repairs you're struggling to do, are even acceptable. Obviously the fix is to fix the automated welding or stop automated and go fully manual.

-ensure that you've got a really good ground to the part

-fire off on filler, not on parent. On thin-fusion and penetration isn't the problem...melt and burn thru is

-see miller setup parameters to tailor arc start first to
the tungsten size, which you don't mention and then
you can still crank the arc start amps and characteristics down more, below the recco'd start.

-the tungsten point prep and cleanliness has everything to do with how the starts going to be on OH-TOO-THIN
(it's amazing that users don't really study the miller setup manuals
on the 350 and 700)

-slow pulse for manual seems to help most of us--like 0.5 to 5 PPS

-I didn't like the miller 'Blue Lightning' hf arc start at first, but
after playing, realized it's just sudden and not as violent as it first appears to be. (The old TA inverter I had, would start at 2 amps, just a tickle, very soft and then could be ramped up.)

-If you're chasing the melt hole getting bigger---just stop, deep breath and wait for the post flow to finish