Help with Tig ally:ceramic tip keeps breaking

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G'day all and thanks in advance,I have a problem with my tigging and since I am the only one in the shop that knows how to tig weld I can't ask for advice.Umm basically what happens is the ceramic tip(most often size '6') continues to chip/brake or shatter whilst weling ally.  Have tried turning heat down to little avail as most of my projects require plenty of heat.  I have never really had this problem untill the past few days.  I have tried to remedy by replacing all nozzle parts, I tried using larger tips(did work kind of but job requires '6' tip) but nothing really helped.  It is getting frustrating running over to the store to get replacement ceramics.  It usually occurs performing a fillet weld, I try not to drag it too much but due to my experiance I am a sloppy freehand.BTW great forums hope to get some pics of some home projects up soon and maybe some welding critique.Cheers
Reply:can you post a pick of the weld?ChuckASME Pressure Vessel welder
Reply:Could it be your supplier got a bad batch of cups?  It's normal for them to get brittle after a while but it sounds like yours are failing prematurely.  Can you get some from another vendor?DennisThermal Arc 185-TSWMillermatic Challenger 172VictorO/AAtlas Craftsman 12 by 24 LatheEsab PCM-875Wholesalem Tool Mill-Drill
Reply:1 - dont tighten down the ceramic cups so much, keep them almost loose, "gently tight"...if you will. They aren't a nut & bolt that is subject to shear force, it only acts as a gas guide. 2 - it could be possible if the above is confirmed, that you have a bad or cheaply made set of cups. What kind are they?John -  fabricator extraordinaire, car nut!-  bleeding Miller blue! http://www.weldfabzone.com
Reply:The "Lava" type gas nozzle (cream color) may handle the extreme heat of high current aluminum welding better than the "Alumina" type (red).  Can't find a reference on this right now, but that's what I remember.
Reply:I bought a gas lens and 5 #5 cups to try it out.  All of them broke right away.  Next time I ordered different sizes in boxes of ten.  I haven't broken one since.    I also switched to a water cooled torch.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:This is not popular to say but I will say it anyway.DO NOT "WALK" the cup. Do not drag the cup.The #9 cup will work better. The cup you are using has a very small opening.You are talking about a water cooled torch???The ceramic cup needs to give off its heat, so if you have the cup touching the metal or near the molten metal it will be getting overheated on one side of the cup and not getting even heating and cooling from the shielding gas,CHECK your post flow time.I would give it at least 10 seconds.Tungsten stick out from the cup should be correct also for the type of metal you are welding.This so called "walking the cup" is ridiculous.You do not need to post saying you have been doing it all your life.It does not mean it is ok.Last edited by Donald Branscom; 01-23-2008 at 04:36 PM.
Reply:I don't know how you guys break them.. I've never had one fail..The only time I break'em is when I drop'em on the floor and inadvertially step on them.....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Originally Posted by Donald BranscomThis is not popular to say but I will say it anyway.DO NOT "WALK" the cup. Do not drag the cup.The #9 cup will work better. The cup you are using has a very small opening.You are talking about a water cooled torch???The ceramic cup needs to give off its heat, so if you have the cup touching the metal or near the molten metal it will be getting overheated on one side of the cup and not getting even heating and cooling from the shielding gas,CHECK your post flow time.I would give it at least 10 seconds.Tungsten stick out from the cup should be correct also for the type of metal you are welding.This so called "walking the cup" is ridiculous.You do not need to post saying you have been doing it all your life.It does not mean it is ok.
Reply:Walking the cup is a proven acceptable method and aids greatly in controlling torch movement.  What's the problem?
Reply:I don't do any welding that could use walking the cup, but I do "ride the cup" as in slide one side on the plate to help keep me steady.  It helps and aside from the original 5 gas cups I have not broken another one. It works for me.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:I to would like to know why, walking the cup is not good?
Reply:Replies appreciatedIt happened again today, can't be a bad batch, The store has 2 diff brands, both of them broke.I will try all advice posted, also, would turning arc force up and current down help at all?Thanks
Reply:Originally Posted by BiffI to would like to know why, walking the cup is not good?
Reply:Originally Posted by BiffI to would like to know why, walking the cup is not good?
Reply:Originally Posted by SupeWhy isn't it?  If it's not, then we've got some SERIOUS problems in the nuclear and petrochemical fields right now...
Reply:I don't have the energy to address everything said by Donald Branscom about "not walking the cup", or any of the other unrelated stuff, but I will point out a couple of things.   Mechanized welding often does use a mechanical transverse torch weave for TIG welding of a groove type joint, same as a manual welder walking the cup.  Mechanized welds on thinner material with a square butt joint, such as tubing and probably jet engine ducts, are not weaved because there is no reason to.
Reply:new's to me, I always thought it was a normal practice.
Reply:Originally Posted by pulserI don't have the energy to address everything said by Donald Branscom about "not walking the cup", or any of the other unrelated stuff, but I will point out a couple of things.   Mechanized welding often does use a mechanical transverse torch weave for TIG welding of a groove type joint, same as a manual welder walking the cup.  Mechanized welds on thinner material with a square butt joint, such as tubing and probably jet engine ducts, are not weaved because there is no reason to.
Reply:Originally Posted by Biffnew's to me, I always thought it was a normal practice.
Reply:Thinking back about the original post on this thread I think that the #6 cup opening is very small and it could be causing the cracking when a lot of heat is applied to the new ceramic cup. And i believe that was an air cooled torch too.Last edited by Donald Branscom; 01-24-2008 at 11:15 AM.
Reply:Pulser pretty much nailed this one.  In fact, the idea behind walking the cup is to provide greater control than a freehand weave, which can ultimately lead to a reduction in, and more consistent, HAZ boundary.  My statement in regards to the nuclear and petrochemical industry does not refer to the poor design and blatant disregard for quality of projects such as the Alaskan pipeline (in which numerous people faced penalties for falsifying NDE documents, etc).  It refers to the fact that there are ample pipe welders out there right now who are certified and routinely weld large sections of pipe, stainless or otherwise, that have zero failures as the result of walking the cup.  If you want to argue on behalf of the cup not touching the plate, that is fine.  Others will argue against that, myself included, for the vast majority of applications.  Personally, I don't believe walking the cup has many justifiable applications outside of pipe welding, but it most certainly has its place.
Reply:Originally Posted by SupePulser pretty much nailed this one.  In fact, the idea behind walking the cup is to provide greater control than a freehand weave, which can ultimately lead to a reduction in, and more consistent, HAZ boundary.  My statement in regards to the nuclear and petrochemical industry does not refer to the poor design and blatant disregard for quality of projects such as the Alaskan pipeline (in which numerous people faced penalties for falsifying NDE documents, etc).  It refers to the fact that there are ample pipe welders out there right now who are certified and routinely weld large sections of pipe, stainless or otherwise, that have zero failures as the result of walking the cup.  If you want to argue on behalf of the cup not touching the plate, that is fine.  Others will argue against that, myself included, for the vast majority of applications.  Personally, I don't believe walking the cup has many justifiable applications outside of pipe welding, but it most certainly has its place.
Reply:Donald,I see your points and I understand your reasons for prefering not to walk the cup.  I can imagine circumstances where your objections would be valid concerns.However,I'm an older student(starting new career) at a well-respected welding school, and they teach TIG welding pipe by 'walking the cup'.  I was taught to use a "finger stall" to weld pipe sections in the vertical(2G) position.  This allows the welder to maintain proper arc length.  For TIG welding pipe in all other positions I was taught to 'walk the cup'.  I find it impossible to believe that acceptable joint quality could be achieved by a reasonable number of welders without using this technique.  Insofar as welding stainless steel is concerned; it certainly is a tricky business.  I've seen SS weldments in corrosive environments fail due to sensitization(chromium carbide formation or precipitation) of the HAZ.  There's lots of variables to contend with; filler and base metal composition(compatibility), heat input, gas flow, gas composition, the list is almost endless.With due respect to your experience,It seems to me that the added control of heat input, work angle, travel angle, and arc length that are provided by walking the cup outweigh the problems you mentioned in most situations.  Proper joint preparation, gas flow rate, and equipment can address the concerns regarding proper shielding.  And as for wear and tear on the equipment(cups, torch handles, etc) this is just a part of doing business.  Cups will crack, and torches wear out.  They were never intended to last forever.  Buy new ones as necessary.
Reply:I've broken a few cups in my time, by dropping them, letting them roll of the table etc... I've never had one break without some kind of impact involved though. I'm at a loss.Miller EconotigCutmaster 38Yes ma'am, that IS a screwdriver in my pocket!Originally Posted by Joe HI've broken a few cups in my time, by dropping them, letting them roll of the table etc... I've never had one break without some kind of impact involved though. I'm at a loss.
Reply:I've seen the outside edges flake off, almost like knapping a flint.  Eventually the edge of the cup gets a lowspot.  I replace them at this point because they don't walk smoothly down a pipe groove joint anymore, and because I think a small divot in the edge of the cup might do unpredictable things to shielding gas flow.