TIG Electrode Stickout

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I bought a Miller Synchrowave 250 at an auction that is set up for both TIG and stick.  I am pretty familiar with other processes but don't know much about TIG and the thing I cannot find in any literature is how much the electrode should protrude from the front of the cup.  I found out the hard way that too close makes the cup get very hot so I have been moving it out a bit and getting better results but is there a rule of thumb where to start?  I make cabinet hardware from mild steel and need to join pieces with a minimum of bead so that is why I am not using a MIG.  I am using about 90 amps with a 1/16 electrode.
Reply:when i use 1/16" tungstens, i have about 1/8" of stickout, a t joint will require a little moreStangnetShop Full Of Stuff. Joey
Reply:HW,Go to www.millerwelds.com and download the manual for the unit.  It will give you some ball-park parameters.Be well.hank
Reply:When I started learing how to tig I was told the stick out of the tungsten should be no more than the inside diameter of the cup no matter what size electrode being used.
Reply:I started flush with the cup but that made both electrode and cup too hot.  I have since moved out to about 1/8 with a 1/16 electrode and that makes a good arc.  I'm now having the undercut problem referred to in my other post.Get it hot and hit it hard...
Reply:From what I have read you want to have the electrode stickout approx the thickness of the tungsten. So if you have a 1/16 tungsten you would want it sticking out 1/16 from the cup. Keep in mind that is only a starting point.John
Reply:I think that electrode length from the cup falls along lines of what you like. The outer limit is based on shield gas coverage. You may find that some joints require more electrode length to allow getting in close where you need to be. This of course is just one TIG welders opinion.
Reply:that's another advantage of having a torch with the gas valveStangnetShop Full Of Stuff. Joey
Reply:My torch does have a gas valve but I have been just cracking it a quarter turn or so, using 15cfh Ar at the flowmeter.  The electrode ends up either a shiny silver or blue when I finish welding.  I overheated once going up to 150 amps to see what penetration looked like and the electrode slumped over.  I am an old oxyfuel weldor so have not had too much trouble with touching the tip to the work and so far, I seem to have better luck with more stickout.  In fact, at this point I may be beyond some recommendations using 3/16 past the cup.Get it hot and hit it hard...
Reply:In the Navy, when we were doing nuclear system piping welds. They were all run at 60 amps and with multiple passes. I know that we've got some pretty hefty output TIG welder but what are you welding? You don't have to make a weld in a single pass. Your heat affected zone will appreciate it if you don't. Sometime when welding the root pass the electrode will need to be out further to allow you to get deep in the joint. The shield gas is not normally a problem in this situation because the joint design helps keep gas at the electrode. If it is a piping joint and due to interference you need the electrode out further, then you better be getting the gas flow up to keep the electrode covered. Same thing goes if welding with wind affecting the gas but in addition to increasing the gas flow the electrode needs to be close to the cup to prevent air from screwing up the electrode.
Reply:I make cabinet hardware from mild steel and am welding 3/8 round, threaded studs onto 3/16 thick plate.  With or without filler rod, I get a little undercut on the round stock. I am using about 100 amps with a 1/16 electrode and have been pointing the torch at a 45 degree angle into the joint.  I would have to use more stickout to tip the torch so the arc is pointed at the 3/16 plate.  A MIG works for this operation but leaves quite a bit of weld metal and I am trying to get away from post-welding processes that don't add value.Get it hot and hit it hard...
Reply:I take it that you do not have a foot pedal for control of amps? You should be able to manipulate the puddle using the angle of your torch. The puddle will naturally try to drop if the plate is sitting flat and the rod is vertical. I have welded 3/8" rod to 1/2" plate with my TIG . It takes a bunch of amps to get the 1/2" plate to form a puddle and the 3/8" rod didn't like the amps that high. So I manipulated the torch to get what I needed. The foot pedal didn't hurt either. Threaded rod is a bit of a hassle because you have a natural born undercut waiting to happen. Half the material is already gone due to the threads being there. It is even more important to use enough filler material and move it using your torch to control the puddle. You said the torch is 45 degrees. That is in one plane what about the angle of the torch to the joint in the other plane? I normally lay mine back away from the direction of travel. Meaning the cup in front the back cap  facing away from the direction of travel. I almost always travel right to left on the joint. I pretty much never have the back cap and front cup 90 degrees to the work. It messes with your ability to see the puddle and it makes puddle manipulation difficult.  Try different angles of the torch. Normally I will lay it down more when I need to push the puddle up toward the rod. You need to make sure you have enough puddle or you'll get the undercut when you make it up to the rod. Again this is one novice welders opinion.
Reply:Evwelder and JohnV are both right as a good rule of thumb on electrode stickout, so is ddsmith.  You can run anywhere from flush with your cup up to a max of about 1/2" stickout.  More stickout requires more gas shielding.  Sometimes if you're in a tight corner you have to use more stick out.  Rules of thumb:1    At least equal to diameter of electrode especially if less  than      1/8"2   No more than 1/2 diameter of shielding cup if possible3   Never more than 1/2" or diameter of shielding cup
Reply:I'd found some interesting information on tig setup on the CK web site:http://www.ckworldwide.com/Technicalinfo.htmTinkerCentury 135GS, ThermalArc 250GTS
Reply:The CK info is very useful - recommend anyone with a TIG go check it out.Get it hot and hit it hard...
Reply:From what I've read, tungsten stickout should be 1/2 the diameter of the cap.
Reply:Read all of post. I think you should first consider opening the cylinder all the way. I heard that if you don't you have a chance of breaking the valve on the cylinder. Second you mit consider turning the cfh to 20. What type of gas are you using?
Reply:jsmetters,Haven't heard anything about breaking the valve by not fully opening it but I have been taught that if you don't open it all the way you can lose gas.  Since the tank is at such high pressure there is a gas seal in the valve at the bottom when it's fully closed and at the top when it's fully open.  If you leave it in the middle you're not up against either seal.TinkerCentury 135GS, ThermalArc 250GTS
Reply:Originally posted by Tinker jsmetters,Haven't heard anything about breaking the valve by not fully opening it but I have been taught that if you don't open it all the way you can lose gas.  Since the tank is at such high pressure there is a gas seal in the valve at the bottom when it's fully closed and at the top when it's fully open.  If you leave it in the middle you're not up against either seal.
Reply:I have been told the same gas valve recommendation by suppliers on any gas under high pressure including oxygen and inerts, BUT acetylene should only be cracked a turn or two so it can be closed quickly in case of fire.Get it hot and hit it hard...
Reply:Good point on the acetylene valve.  I was thinking inerts when I made the previous post and should have noted that acetylene is only partially opened for the reason mentioned above.Also, although I haven't been welding long enough to see one, I was taught that you should always leave the valve wrench in the valve if the acetylene tank uses one (i.e. doesn't have an attached valve knob).  Same reason as the partial opening..TinkerCentury 135GS, ThermalArc 250GTS
Reply:I have been tig welding for 40 yrs. and stick out is purely a matter of preference. I almost always stick out approx. 1/4 inch. I never use 1/16 tungsten, always 3/32 or 1/8th. Grind the tip to a pencil tip and unless youre welding in the wind, 10 cfh of flow should be plenty. If you're welding Aluminum then 20 cfh. and green tungsten.  This from an old pipe welder....Glenn
Reply:Glenn,Thanks for the info.  I'm using 1/16 diameter because that's what came with the unit when I bought it at auction.  My continuing problem is touching the tip to the work.  I'm a pretty fair hand with an O/A torch but the coordination for TIG is a bit different.  I am getting better but still don't have the correct bracing for my torch hand to eliminate wiggling.Get it hot and hit it hard...
Reply:My vendor told me a while back that the local colleges are telling their students that red is the best all around rod and they are teaching them on it.  That includes aluminum.  I'm not sure what to make of it, but I run red for most all of what I do and I've noticed that I have to flip/flop from 3/32 to 1/8 quite a bit when I'm welding aluminum depending on the thinknesses or I'll loose the end.  Either I'm getting heavy footed or it's the rod I'm using.Common sense in an uncommon degree is what the world calls wisdom.
Reply:The tungsten type is very much machine depend now days.  In the past pure tungsten, (green),was used pretty much exclusive for aluminum and thoriated, (red), for every thing else.  I tended to like zirconium for AL.  However with the advent of the switching power supplies, (inverters), one electrode can be used in different operating settings, (ac/dc), hence different materials.  I personally like the lanthanated stuff.  For under 120 amps or so it just seems to perform and hold up the best with my machine.  I use it for both AL and mild steel.Is EWLa-1 more expencive than EWTh-2(Thoriated)?  I've been wanting to check some of the other ones out.. The more I read about the radiation I get every day from welding, the more I want to check into different options.Common sense in an uncommon degree is what the world calls wisdom.