Walk the cup technique; couples of questions

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I watched some videos on the technique but I have some questions.1) Looking a the "feeding hand", it doesn't look like they are dipping-retract-dipping-retract...  it seem more like they just keep the tip at the edge of the puddle and the filler just melt in as the cup advance on the joint.  Is that it?2)What about different thickness T joint/corner joint; Should the puddle concentrate on the thickest part of the joint?  Should the cup "spend a bit more time" on the thickest side of the joint?Thanks in advance!USINUM - CNC routing workshopPaco's area - blogspot---Lincoln MIGpack180 (GMAW - FCAW)Miller Syncrowave 250
Reply:the first technique is not unique to walking the cup. On some joints and layouts it's possible to just lay the rod down and wash it out. However on things like stainless and the likes the heat tends to travel back up the rod and oxidize it, or it melts inconsistently into big globs of ugliness.  Some people consider it a "weak" technique.  I do it from time to time. and seem to do it more on root passes and fill passes in narrow bevel joints.On a different thickness T joint, yes usually you'll concentrate more on the thicker section. If the thickness is too great you will need to preheat the thicker section to 200-300f and keep it there while welding.If not then yah just dwell at little bit more on the thick section or angle your torch so the heat stays there. Also it can be a good idea to dip your rod on the thin section, because the rod will cool the puddle.Really though IMO there's not a big difference between cup walking and free hand, besides the motion your hand makes. The welds can look and behave identically.
Reply:Is  walkin the cup suitable for when you cannot rest you hand or steady your arm against a rest of some sort? If the cup rim is in contact the electrode isn't as likely to dip into the puddle.
Reply:Ive heard people say walking the cup is a crutch for those that cant free hand.  Anything that can take variables out of the welding process can be a good thing.  Resting the cup on the metal takes the unstable hand out of the equation.  Resting the filler rod in the groove takes inconsistant dips and a shaky filler rod out of the equation.  Have yet to see a free hand weld look as good as a weld done by walking the cup -although is possible, just haven't seen it.
Reply:Hello Paco, some might disagree, but walking the cup is very common and likely developed with pipe welding in mind. I would disagree with those who might think that it is only employed by those who can't freehand. Lay-wire is a term often applied when folks are applying beads by walking-the-cup and not dipping the filler. Lay-wire technique on root passes of pipe will generally provide a very uniform and sound profile on the inside of the pipe, this technique can be very important in cases where the internal profile is subjected to stream eddying or in the case of such processes as paper pulp production. Depending upon the operator, many will utilize various diameters of cups for root-pass applications and vary the diameters as they move from the bottom of the groove outwards towards the cap if the welds are to be done "all the way out". Some will only utilize a very limited amount of size changes, mainly an operator choice and likely how they learned or were taught. There are many folks out there who could be compared to a machine with the skills that they possess to apply this particular technique. Just a few additional thoughts for your consideration. Best regards, Allanaevald
Reply:anyone who thinks cup walking is a crutch is one who hasnt been able to master it..it looks easier than it is..like  most welding..i do it for asepetic purposes as it makes a good purge on both sides....in a purely aseptic application at times filler rod is not added
Reply:you want to keep the filler close  to the arc..  so it stays shielded..you dont retract it..feed it into the puddle by walking the  thumb and two fingers away from the puddle..i used to keep a weldrod in my car to practice the feeding thing while driving..
Reply:Originally Posted by aevaldHello Paco, some might disagree, but walking the cup is very common and likely developed with pipe welding in mind. I would disagree with those who might think that it is only employed by those who can't freehand. Lay-wire is a term often applied when folks are applying beads by walking-the-cup and not dipping the filler. Lay-wire technique on root passes of pipe will generally provide a very uniform and sound profile on the inside of the pipe, this technique can be very important in cases where the internal profile is subjected to stream eddying or in the case of such processes as paper pulp production. Depending upon the operator, many will utilize various diameters of cups for root-pass applications and vary the diameters as they move from the bottom of the groove outwards towards the cap if the welds are to be done "all the way out". Some will only utilize a very limited amount of size changes, mainly an operator choice and likely how they learned or were taught. There are many folks out there who could be compared to a machine with the skills that they possess to apply this particular technique. Just a few additional thoughts for your consideration. Best regards, Allan
Reply:Originally Posted by weldbeadyou want to keep the filler close  to the arc..  so it stays shielded..you dont retract it..feed it into the puddle by walking the  thumb and two fingers away from the puddle..i used to keep a weldrod in my car to practice the feeding thing while driving..
Reply:Hello WHughes, I believe you are correct about the origin of the technique. Buzz Culbert, his son Gary, Ed Hue, and others were a big part of that. Additionally, Hanford(being in CBC and 598's backyard) was a driving force for development of advanced and reliable welding processes and techniques so there was plenty of need driving that. Glad to hear that you are associated as such. Best regards, Allanaevald
Reply:Originally Posted by jonesgIs  walkin the cup suitable for when you cannot rest you hand or steady your arm against a rest of some sort? If the cup rim is in contact the electrode isn't as likely to dip into the puddle.
Reply:Originally Posted by Metarinkathat's exactly why you do it. Gives your arm a rest, lets you keep your arc gap more consistent and once you have it in muscle memory you can do it all day long to get a nice even bead.I don't know why anyone would ever consider it a crutch? it's harder to learn than free handing, unless some people think giving your arm a break or having a nicer looking bead is a crutch.
Reply:personally i think walking the cup is much better than freehand.  it gives you the best looking bead. sometime there is no choice but to freehand when you are in a tight spot.
Reply:Originally Posted by Metarinkathat's exactly why you do it. Gives your arm a rest, lets you keep your arc gap more consistent and once you have it in muscle memory you can do it all day long to get a nice even bead.I don't know why anyone would ever consider it a crutch? it's harder to learn than free handing, unless some people think giving your arm a break or having a nicer looking bead is a crutch.
Reply:Paco,Just spotted this post.1 - I was taught to lay the wire in the pipe joint and keep gentle pressure on the wire.  Moving the cup forward consumes the wire and incorporates the weld filler metal into the joint.  You can pull back on the filler metal rod, or push more of it into the joint.  But the odds of dipping the tungsten into the puddle go up some.  You've got to have the right arc length, amperage setting, travel speed, and filler metal size in order for everything to work in concert.  When it does, the welding goes very smoothly and easily.  The weldor can concentrate on keeping the toe lines even and the bead width perfect.  If you don't have the perfect setup, then you'll have to manipulate the filler metal rod in order to get a perfect bead.  It just takes some practice.2-  When welding two pieces that are different thickness, spend more time with the arc on the thicker piece of base metal.  Practice will tell you how much time is necessary.  One word of caution for fillet welds and lay wire techniques.  I was taught to always dip the filler into the puddle when making fillet welds.  You can use the laywire method, but if your heat setting is too low, or your bead is weaved too widely, or you travel to quickly, you can get a lack of fusion at the root of the joint.  It's possible to get a hollow 'tube' at the base of the fillet where the filler metal doesn't fuse into the corner where the two sides of the base metal meet.  You'll never be able to see this type of defect visually.  Dipping the filler rod ensures that this type of defect doesn't occur.  For those that think walking the cup is a crutch; they're wrong.  It's good technique that has a number of benefits.  It smooths out the welder's travel speed and maintains a constant heat input.  This is important when welding stainless or chrom-moly piping; as the heat input controls the properties of the weld and surrounding heat affected zone.  It also aids in reducing the overall number of defects that occur in welding.  Not all weldors are equally skilled.  Anything that makes the job easier, and reduces welding defects is better for everyone involved.  What's the value in free-hand TIG welding if 25% or 33% of weldors can't do it consistently?  If walking the cup anables those guys to do the job right, we all benefit.  Customers get better quality with lower risk of a future failure.  More weldors are able to pass the test and get the job done in a timely fashion.  I suppose you could look at this as a crutch, but I think those that do so are being arrogant and foolish; in the grand scheme of things. Originally Posted by PacoI watched some videos on the technique but I have some questions.1) Looking a the "feeding hand", it doesn't look like they are dipping-retract-dipping-retract...  it seem more like they just keep the tip at the edge of the puddle and the filler just melt in as the cup advance on the joint.  Is that it?2)What about different thickness T joint/corner joint; Should the puddle concentrate on the thickest part of the joint?  Should the cup "spend a bit more time" on the thickest side of the joint?Thanks in advance!