Spray transfer mig torch angle

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I’m welding (multiple) 30 inch 2g t joint on 3/8 mild steel with ~3/8 toes. My company requires this weld to be run at 26v 280 wfs with 1.6 mm wire on 90 argon 10 co2. I’m running a straight push getting equal toes but can’t seem to get it to fill in perfect. Any tips? My boss and the other welder don’t have any advice and think the welds I’m putting are good, but I know they could be better.
Reply:

Originally Posted by racecar616

I’m welding (multiple) 30 inch 2g t joint on 3/8 mild steel with ~3/8 toes. My company requires this weld to be run at 26v 280 wfs with 1.6 mm wire on 90 argon 10 co2. I’m running a straight push getting equal toes but can’t seem to get it to fill in perfect. Any tips? My boss and the other welder don’t have any advice and think the welds I’m putting are good, but I know they could be better.
Reply:

Originally Posted by shovelon

Why are you pushing????? Does your procedure require you to push? Depending on the power supply electrical characteristics pulling will get better penetration to the root and wet the toes better IMO. Only with alum or flux core would I push. Even then I pull sometimes when in a pinch.
Reply:I personally like to pull spray transfer slightly, not massively but by maybe 10 degree's, I find I get a nice bead profile that way, pushing usually gives me a slightly concave weld profile.
Reply:So straight push I’m running perpendicular with maybe 5-10 degrees push because I found it to give me a way better better bead. I started out pulling and my toes weren’t filling in and the bead was rolling over
Reply:I’ll try that perhaps I was pulling at slightly too steep of an angle
Reply:I'll be more specific with my query (not a disagreement or challenge). My query is based on curiosity more than anything.

Originally Posted by shovelon

Why are you pushing????? Does your procedure require you to push?Depending on the power supply electrical characteristics pulling will get better penetration to the root and wet the toes better IMO.
Reply:2 things were discouraged when I was steel mig/arc trained in college. Pushing and downhill progression. Both can result in lack of fusion to the root and a concave weld profile, slag inclusions, and possible overlap in the toes. Sometimes you have to do it in a pinch but I hate it. However alum mig is always a spray arc process with smut being deposited in the root. Pushing lifts the smut out of the root and the coefficient of heat tranfer gives decent wetting at the toes. Pulling alum mig may bunch up the puddle causing due to the arc transfer from said puddle. That is the way I was trained, it works for me, and I stand by it faithfully.Weld like a "WELDOR", not a wel-"DERR"

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Reply:

Originally Posted by shovelon

2 things were discouraged when I was steel mig/arc trained in college. Pushing and downhill progression. Both can result in lack of fusion to the root and a concave weld profile, slag inclusions, and possible overlap in the toes. Sometimes you have to do it in a pinch but I hate it. However alum mig is always a spray arc process with smut being deposited in the root. Pushing lifts the smut out of the root and the coefficient of heat tranfer gives decent wetting at the toes. Pulling alum mig may bunch up the puddle causing due to the arc transfer from said puddle. That is the way I was trained, it works for me, and I stand by it faithfully.
Reply:Pushing and pulling are both acceptable techniques to used in GMAW spray transfer. Dragging creates deeper penetration but requires a higher skill level to operate. Pushing creates a more uniform weld profile with less chance of undercut. Both techniques are essential to learn but ultimately it is up to the employer on which one they want emphasized (if your not self employed). If we set up two 1/4" material thickness T-joints and used both methods.... which one would have superior penetration and profile? Well that would come down to who is doing the welding! In spray arc welding penetration should never be a problem. So is dragging therefore necessary? I was taught to push only, but have since realized that is complete nonsense.Lincoln 275 SquarewaveLincoln SP 250
Reply:

Originally Posted by Zebidiah

Pushing and pulling are both acceptable techniques to used in GMAW spray transfer. Dragging creates deeper penetration but requires a higher skill level to operate. Pushing creates a more uniform weld profile with less chance of undercut. Both techniques are essential to learn but ultimately it is up to the employer on which one they want emphasized (if your not self employed). If we set up two 1/4" material thickness T-joints and used both methods.... which one would have superior penetration and profile? Well that would come down to who is doing the welding! In spray arc welding penetration should never be a problem. So is dragging therefore necessary? I was taught to push only, but have since realized that is complete nonsense.
Reply:

Originally Posted by Jack Ryan

I have no problem with that at all. The point that I was making is the the hard and fast rules should not exist as depending on the situation, it may be necessary to drag or to weld vertical down or some other sin. Each in its place so to speak. I think some of these rules come from early training where it is "safer" to do one thing over another. They should fade away with experience but that is not always the case.Of course some procedures (codes) require that things be done a certain way but that is a different kettle of fish.RegardsJack
Reply:

Originally Posted by Zebidiah

Agreed 100%. A lot of the hard and fast rules that welders hold dearly, actually started out somewhere as "shop rules". If you can't back up what your saying with AWS or similar code your just speaking to what you've been taught. Doesn't make it wrong, just incomplete. Whats acceptable in one shop is not the same as the next (often even within the same company). I cringe when I'm working with a welder that wants to argue about how he did a particular procedure at his last job. I usually reply with "your current employer wants it done this way". I'm all for discussing expectations. There is also a time and place to discuss deviations. However it is not before you know the rules well enough to break them. Thus "shop rules" are created ha ha.
Reply:One of the biggest wives tales is regarding the width of weave on vertical up on mild steel. A lot of places and weldors claim max. 3 electrode diameters, some 2 1/2 diameters. Wanting to get official clarification several years ago I sent an an e-mail to Walter Sperko who is one of the top people behind ASME codes. He said he would challenge ANY procedure that lists a maximum weave width on mild steel or common boiler plate. He also said more heat is better and as long as there are no slag inclusions you can weave as wide as you like. Somebody said something back in the 60's or whenever that wasn't based on anything but people take it as the gospel. Funny that I had e-mailed another weld qualification inspector who also said 3 times diameter. I think I'll I'll go by what one of the ASME code writers says. On stainless you want/need to limit weave width and heat input.
Reply:The other thing to remember with weaving, is that you're massively increasing the heat input per pass, which can be a bad thing, especially on highly restrained joints or crack sensitive material.So there is a good reason for running stringers...As for torch angle, straight wire i was taught to push, no matter the transfer mode. Only a slight push angle. But it's OK to pull, too. Always got plenty penetration. If I pull, the weld bead goes too concave.

Murphy's Golden Rule: Whoever has the gold, makes the rules.