Bright Flares

Aluminum welding is coming along , just need lots of practice now . But SS is still giving me problems . Seems no matter how much or how little surface
prep I do I still get these really bright yellow/orangish flares . Sanded a piece this am with a flap wheel to knock off any surface contamination , still flares . This is so bright that it blinds me , even with my helmet set on shade 12/13 . I've tried varying my gas flow <now using a gas lens> , tungsten stickout , angle of the torch , nothing seems to work . It also does that a little bit with mild steel , but nothing like with SS . My beads also look black and sometimes a little pinholed . I've gone from a regular collet/cup to a gas lens setup .Tried it with #6 and then #7 cup <on the lens> , and still no joy . This is almost more frustrating than my early attempts on aluminum ! Steel and it's various alloys are supposed to be easier ! -- Snag Color me puzzled .
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On 9/1/2013 12:16 PM, Snag wrote:

Are you using any kind of back-side purge on your stainless welding?
BobH
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BobH wrote:

Not for laying beads on the surface of a plate. At this point that's all I'm trying to do .
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"BobH" <

Did you change tungstens? And cup? pdk
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All brand new except for the back cap . Virgin 3/32 electrode , sharpened it just for a test per your suggestion , new gas lens and #8 cup . Hit the SS with a flap wheel then straight to the stool with aluminum plate on top I'm using as a welding "bench" . Same thing , flares and a nasty looking surface on the bead . Tried increasing gas flow , decreasing gas flow , went back to 15SCFH where I usually have it . Same thing , flares . I even tried AC , no flares but a nasty popping sound and another ugly bead . I'm beginning to wonder about this material , like most of my little stock pile it has spent a year or five outside in the weather . -- Snag
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"Snag" <

Next thing to check then would be the entire length of the shield gas circuit for leaks, just to clear that item.... then electrical connections, then machine settings, then ? , the machine itself.... can't help there.
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Phil Kangas wrote:

I grabbed a short piece of new round stock , did a pass across the end . No/minimal flares , it looks like the problem is that my material has contaminants in/on it . I thought sanding the surface would get rid of whatever might be on it , guess I'm wrong . I'll be getting something that hasn't been laying out in the weather for further practice .
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Perhaps that stock was cadmium or zinc plated? Even though the weld zone is cleaned that plating will migrate to the hot area and react with it. But you said it was SS? hhmmmph...now what.. :>(} I'm out...
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wrote:

Wipe your suspect stock with acetone and let it evaporate and try it again. Thats a normal tactic for many TIG operations btw.
Gunner
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AC or DC..and which polarity are you using?
"
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Gunner Asch wrote:

DC electrode negative
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wrote:

Fair enough. Try an acetone wipe of the material and see if that cleans it up. If not..you got some flakey stock based on your last post.
"
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I'll have to pick up some acetone , don't have any right now . The stock I'm using came free from a cabinet shop where I worked , piece about 8' long 7-8" wide bent into a sort of z shape . It's been out on my scrap/stock pile behind one of the sheds vfor a fewv years now . It's not magnetic , probably a 300 series . I did try out some other pieces I have , much better - it's new material left from a job . -- Snag
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You are using Pure Argon right? And its worked like this with every bottle?
And what is the hoods delay set at?
Gunner
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As far as I know it's pure argon , I got the bottle second-hand and full . Welds aluminum just swell . I have the machine set for about 3 seconds pre and 3 post flow . Or are you talking about my welding hood - it's set on shade 9 and minimum delay . Even on shade 12/13 these flares are bright enough to pretty much blind me . -- Snag
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Set the hood on sensitive and long delay. Sounds like you got the right gas..assuming its not a mismark
Guy was telling me last week he got a bottle of nitrogen in a shipment of argon that they used in a gas envelope heat treater. Fucked up about $15,000.00 worth of parts. The lawyers are going to have fun with this one...it was nitrogen in a bottle marked argon.
Gunner
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Heh , the bottle is marked C25 ... but when I tried it out on my MIG welder , it sure don't act like C25 . As I said , it welds vwell with aluminum . That acetone trick will work with aluminum too , I bet . -- Snag
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Not so well. the contamination on aluminum is aluminum oxide and needs to be either mechanically or chemically removed. Likely insoluble in acetone.
--
Cheers,

John B.
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Try switching back to a normal cup. I once had a gas lens get clogged (I guess) and acted about the same way.
Stainless doesn't usually require a lot of surface preparation. I weld stainless tube - the 1" shiny tubes - with no prep at all.
Someone else mentioned backing gas but I've welded a bunch of stainless with no backing and never had a problem with black welds and flaring.
You might also try turning off the gas and striking an arc. If you get the same black marks and flaring you've got a handle on the problem..... but you'll need to re-sharpen the tungsten :-(
--
Cheers,

John B.
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The gas lens set I'm using is brand new , I doubt it's clogged - looking at the flowmeter there's definitely gas coming out .

The guy that let me try out his TIG setup does basically no prep , but his stock is brand new and gets rotated frequently .

I laid the torch on the bench so that when I hit the pedal it'd strike an arc on a piece of this SS , then while it was running set the gas flow . It seems to do best with about 15 SCFH . While setting it , I turned flow down enough that I could hear the difference in the arc .

Gunner suggested an acetone wipedown , I'll try that on my stock and the rod . New stock was much nicer to weld on ... with and without filler . -- Snag
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