Need Help!! Robotic Welding with .035 308lsi 1/8" fillets!!!!

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Having major issues with the stability of the arc due to wire casting and/or distortion due to 3/16 thin stainless material.  Any suggestions regarding wire straightners, or automated devices that can attach to a Kuka robot that will allow me to move the TCP up or down in a joint to maintain TCP accuracy in the joint.  I am looking into ServoRobot laser guidence systems for online tracking of the joints, but I am looking to see if there is a cheaper option that will allow for online adjustments of the TCP.  I am using a Fronius CMT 5000 powersource, and I'm welding at around 160Amps and around 21-23 Volts using Stainmix, which is a tri-mix of He, AR, CO2.  I have ordered a spring loaded contact tip from fronius to hold the wire better in place.  The major issue I'm having is when I program the robot with a freshly snipped piece of wire, the TCP is right in the joint, as soon as I strike an arc, the TCP changes.  I am thinking this is due to the wire cast, or possibly distortion.  Again, any help would be greatly appreciated!
Reply:What type of container is the wire being fed from, and is there any type of cast/helix requirements in the WPS?Have we all gone mad?
Reply:From a level wound spool, the wire is anealed to help with the softness and casting.  24" cast... no WPS requirement.
Reply:What seems to be the issue when watching the Arc while it is welding is the cone of the arc seems to favor which ever side it is closest too and will switch from time to time, the arc seems to not like the center of the joint where the two plates intersect.  It seems very sensitive to any kind of distortion that will pull one side of the plate closer to the Arc thus causing the Arc to direct the puddle to the top or bottom of the joint even though the tip of the wire is still pointing right at the crack of the joint.  It looks very odd when you this happening, and is very frustrating with such a sensitive weld bead.
Reply:Gravity does not take any effect with such a small fillet weld, so I would appreciate no comments regarding work angles for I have tried everything in that retrospect.
Reply:I'm not familiar with the ratios in stainmix, what percentages of He to Ar are you running?  If it is not already you might want to look into switching to an Ar heavy mix to help with arc stability.Short-circuit transfer I assume?Have we all gone mad?
Reply:Need more info.--How long are the welds?--What is your WSO6 Miller Big Blue 600 Air Paks2 Miller 400D6 Lincoln LN-25's4 Miller Xtreme 12VS2 Miller Dimension 812 4 Climax BW-3000Z bore welders Hypertherm 65 and 85Bug-O Track BugPair of Welpers
Reply:My welds are approx. 24-36" and I don't know what you mean by "WSO" The stainmix allows me to weld in a medium short circuit process, I will look into the 100%AR.What are some high quality wire straighteners that are designed for ARC welding Robots?
Reply:Yesterday I tried using a .030 308 LHS Wire to see if a smaller wire would help with welding these VERY small fillets.  I am having some difficulties in trying to decide whether a fast travel speed and more wire speed vs a slower travel speed and less wire speed would yield better results as far as ARC stability VS part distortion.  I am trying to see if the robot's fast travel speed can beat the rate of distortion from the weld thus allowing me to weld full 36" continuously.  I am thinking though, that above 20 IPM, the stability of the ARC is degraded.  Anyone have any insight on this? Trying to get a nice over sized 1/8 fillet.  What are some recommended travel speeds that anyone has tried robotically?
Reply:Are you pulse welding with the TPS?  If so decrease the value of your arc length correction.  The spring loaded tip will help with contact tip wear and arc stability.  They also sell a stainless tip that you can use to check your TCP with and make sure thats not varying on you.  It could be a worn out wrist on the robot arm even that would cause some of those issues.I play with Robots and do some welding.
Reply:Originally Posted by critt540My welds are approx. 24-36" and I don't know what you mean by "WSO" The stainmix allows me to weld in a medium short circuit process, I will look into the 100%AR.What are some high quality wire straighteners that are designed for ARC welding Robots?
Reply:Originally Posted by critt540My welds are approx. 24-36" and I don't know what you mean by "WSO" The stainmix allows me to weld in a medium short circuit process, I will look into the 100%AR.What are some high quality wire straighteners that are designed for ARC welding Robots?
Reply:Originally Posted by ExpatWelderFor spray or short circuit transfer on stainless, you want AR+3co2----WSO means Wire Stick Out---very critical with robots.
Reply:Usually when working with robots it's called WSO, maual it's CTWD----don't know why the different terms for essentially the same thing.6 Miller Big Blue 600 Air Paks2 Miller 400D6 Lincoln LN-25's4 Miller Xtreme 12VS2 Miller Dimension 812 4 Climax BW-3000Z bore welders Hypertherm 65 and 85Bug-O Track BugPair of Welpers
Reply:In general, I try to get the stickout as close as possible so that the wire cast does not have as huge of an effect on the TCP.  It's around 1/2" and I am running 40-50 CFH.  The material I am welding on is 3/16 304 Stainless. The project is a Stainless Glove Box for Nucluar Pellet inspection so every weld has to be perfect.  The WPS calls out for a 1/8" fillet, this means that a half of a millimeter can make or break the weld.  Fast travel speeds have proved to make the arc more unstable with the puddle from the arc changing from the bottom wall to the top wall back and fourth along the seam.  Because it's such a cold, small puddle being that I am in a CMT+Pulse process welding around 20V and a 100A, makes it very sensitive. It seems that the Arc would rather collect on the top or bottom sides of the joint rather than in the actual crack which is really weird.  I am going to try a travel speed around .27 meters/min.   I have been running .30 which is equivalent to 12 IPM, but I am going to try something like 11IPM.  I thought that by possibly changing to a .030 Stainless wire would help with such a small fillet, but I don't think that it's helping so far.  Testing is still in the beginning stages, and I have had some decent results, but only for around 6-8" before the arc transfers to the top of the joint due to the small 3/16 plate distorting towards the TCP.  I am thinking that I will need to use through the Arc tracking, but I need to get a more forgiving weld puddle that will not fluctuate to small variances in the TCP.  I am going to use a heavier Ar mix here on my next test to see if being in a spray will yield better results.  Thanks everyone for all your comments and suggestions.  Has anyone here ever had any issues with 1/8" fillets on such thin material? Is there anything I haven't tried yet that I should look into?Thanks!
Reply:Find a guy that does nuke work tig welding and see if he can lay a straight bead that meets the specs, just a suggestion, not sure if its even feasible.
Reply:You never addressed why the piece was moving so much, it seems like that is the biggest problem.  Get adequate fixture first, knock out problems one by one and starting with the most obvious.  If the work is moving in the fixture, dont go and invest in thru-the-arc monitoring.  Have you gotten in touch with fronius yet?  If your having problems with arc stability on low amperage CMT they would be my first call.Have we all gone mad?