Majior porosity issues with Lincoln 255xt

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I have a 2 year old lincoln 255xt that i use daily, and last night i started to have some majior porosity issues.  The porosity is instant.  As soon as the trigger is pulled, and the wire hits the metal, its spattering and contaminated.  My tank shows nearly full with 75-25.  I pull the trigger up near my ear and i hear the gas flowing.   Im not sure how this has come about, i was welding last night, stopped to talk to a friend that stopped by, and started again... and now this.  Any suggesgions?  Natrually, i would think this was a gas coverage issue, because its instant, but ive tried increased gas, and decreased gas, and nothing fixes it.  I can hear gas flowing, so i dont think thats the issue...Contaminated wire?  its half way through a large spool, never had an issue before now.  No fans blowing, no drafts, no windows open.What am i working with here?  Ive got some important work i want to get done this weekend, but im stumped as to what the issue would be...ThanksTaylor
Reply:Did u check your nozzle and tip for clogs?
Reply:I use a Bernard gun and as soon as I start getting unexplained porosity issues, I immediately change out the gas nozzle. I find that after a time the fiberglass sleeve inside gets frayed from tools used to clean the tip and it will result in porosity every time. It sure makes you swear...never happens where you can easily clean it out, always seems to take place up in a corner where you can't get at it
Reply:I have removed the nozzle, put it in my lathe and cleaned it very well.  I put a new tip in it as well.  I do not have a spare diffuser or i would swap that as well.  none of this has helped yet.  Im absolutely stumped by the instant porosity thing.  Ive never heard or see this happen before, ive see porosity issues when welding, but ive tried on multiple pieces of steel, and settings, and found nothing that will help.is it a problem inside my machine??Im hoping this is a consumable issue, gas, wire, tips... gun... something like that, because this machine has worked great, and is pretty damn new.Taylor
Reply:I'm wondering if you really have as much gas as you think you do.With the cylinder off, can you purge the system and watch the gauges both drop? When you turn the cylinder back on, does the pressure go back up on the gauges? If the gauge is bad, it may read that you have lots of gas, yet the cyl may be below the amount needed to flow what you have the reg set at. You'll still hear gas, but in reality the cyl is for all purposes "empty". Usually a clear sign of a bad gauge is that the needle is stuck and you have to tap the gauge to get it to drop after you purge the lines.A simpler check would be to just swap over to a 2nd cylinder of gas and see if that fixed the problem..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Swapped out the tank for my TIG tank that is pure argon.  Did the same thing.....help.....
Reply:Did you drop or hit the torch on anything? It could have damaged something inside. If not then maybe your gas line is dirty?
Reply:Not to make you feel dumb but is your gas connected to the right input? On the 255xt i believe there r to inputs, one for spool and one for without. check to make sure everything is connected properly. Maybe the timer thing is messing you up but i dont know that much about the 255xt. Thats all i can think. Good luck.
Reply:Two things that have happened to me when that problem occured was:1. First time it happened I had made the switch from welding with flux core and forgot to change configuration on my welder. 2. I ran into some metal that had some sort of contamination on it. As soon as I switched to a different piece of metal problem went away so cleaned the metal I had been working with and tried again with no problems.
Reply:This welder has been in use for 2 years.  I only use it on mild steel with 75-25 gas.  I weld with it 5 days a week, and it has preformed flawlessly through that time.  Ive never switched it for any other wire, or any other gas lead.  This machine is for my mild steel MIG only.  I have other machines for the rest.Prior to this issue, i was welding up a narrowed rear end, had been welding for 10 minuets with no problems, stopped to talk to a friend that had stopped by, then resumed welding, and this occured, and has not gone away.I have tried welding on different steel on my normal weld table, still nothing, instant contamination.  I shut it off, cleand the welder, the nozzle and all, still instant contamination.I just have no idea what to try next.  Or what it could even be.   Lincoln dosent have a tech support line, so idk who to call.  my local airgas store is full of counter smilers that dont know much about the actual welders besides the price.Im a rational person, so i have tried all the basics.  Im great at trouble shooting this type of thing, yet i find my self nowhere with this problem.  Ive eliminated a few varriables, but just dotn know where to go next.How common is wire contamination?  the spool is about half gone, and the welder iskept in a dry environment all ways... the wire also looks very clean, no surface rust or anything.Im honestly starting to get a bit worried.  IDK what to do about this.Taylor
Reply:Maybe call Miller they may be willing to help if they can. Or if they can. Change the wire and if it persists maybe take it to a welding repair shop if one is nearby. That sure is a pickle though.
Reply:Originally Posted by tamollymanMaybe call Miller they may be willing to help if they can..
Reply:LMAO,Yeah.  Call Miller.  I'm sure they'll help you troubleshoot a Lincoln machine.I'd recommned disconnecting the gun and checking the O rings.  A bad O ring or loose connection can allow gas to escape or pull in air.ESAB, I believe, makes a tool that attaches to the nozzle and measures actual gas flow at the nozzle.Have you tried increasing/decreasing the flow rate to see if it makes a difference?Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:yep, tried increasing the gas flow, and decreasing it.  nothing changes.  I can hear a difference at the tip so i can tell that its actually regulating it, but i obviously have no idea at what amount just by ear.Miller wont help without a serial number, so that wont work.I just cannot wrap my head around what would cause this.  It may be an issue in the gun, but it seems really strange that it would go out suddenly like that, i figure that will be a deterioration type situation.I will be honest, im very disappointed and angry and the whole situation right now.
Reply:Not familiar with your welder but I am sure that someone here that is will chime in. My mig welders I can install a small spool which ony cost about $7.00 to buy at some of the stores, if you can do this to yours would be a quick and cheap way of checking to see if the problem is due to your wire. I have heard others that have either not had the lead plugged in secure to the front of their welder or had bad o-rings as was mentioned and was found to be their problem.
Reply:Just checked the O-rings.  they appear fine.  Still in great shape, no rough spots or deteriation at all.Im going to try a new spool here in a  minute, maybee that will help...Can a spool get contaminated like that out of nowhere?
Reply:New, small spool of wire.  Same problem.Im clueless.Taylor
Reply:What wire are you using?  Brand?  Wire contamination is rare.  You said you were welding on a narrowed axle.  I would assume you were welding really hot.  Could you have exceeded the duty cycle on the gun and burnt it up?  This could cause it to suck air if something burnt inside.  Make sure the gun connection to the machine is seated all the way into the socket in the machine.  Maybe try the regulator from your Tig machine.
Reply:Using .035 Wire, off hand I dont know the brand name, its the higher priced stuff that comes in the 40lb spool.  I was not welding all that  hot really, its only a 1/4" thick axle, and it wasnt 10 minuets straight, like 15 seconds straight at the most, stopping, rotating the axle, then going again.  Maybee 2 minuets of actual welding in that 10 minuets, spaced out.  Ive pushed this machine MUCH harder than that in the past welding thick plate, and never had a problem.  What besides poor gas coverage would cause this?  Is there something inside the machine that could have fried that would make this happen?I dont think its poor gas coverage, but i have no way to tell, besides by ear and i can clearly hear coming down the nozzle.This is very very weird.Taylor
Reply:It might help if you were to post some pics of the porous welds you are getting.
Reply:Here is a quick picture.Each one is just trying to get a quick tack to work.  This obviously is not the axle, this is from the second piece of metal i tried to eliminate the problem being dirty metal on the axle i was welding.Its instantly garbage, no puddle or anything.Taylor
Reply:pull the cover and start checking with the multi-meter if all else has checked okit may have just drop a wire offidealarc 250/250 ac-dc tigidealarc 250/250 ac-dc tig #2 used for sticklincoln sp100hh125dual arbor grinder polisher30 yrs of hand tools52 pitch blocks 6p-26prake gauge -pitch gaugeG&D prop repair 918-207-6938Hulbert,okla 74441
Reply:Originally Posted by JeebusUsing .035 Wire, off hand I dont know the brand name, its the higher priced stuff that comes in the 40lb spool.  I was not welding all that  hot really, its only a 1/4" thick axle, and it wasnt 10 minuets straight, like 15 seconds straight at the most, stopping, rotating the axle, then going again.  Maybee 2 minuets of actual welding in that 10 minuets, spaced out.  Ive pushed this machine MUCH harder than that in the past welding thick plate, and never had a problem.  What besides poor gas coverage would cause this?  Is there something inside the machine that could have fried that would make this happen?I dont think its poor gas coverage, but i have no way to tell, besides by ear and i can clearly hear coming down the nozzle.This is very very weird.Taylor
Reply:I think its getting air mixed with gas.Real world weldin.  When I grow up I want to be a tig weldor.
Reply:Check the tubing connections, fittings from the gas inlet on the feeder, and the gas tubing connection at the torch butt socket--inside the feeder. These don't leak-often, but they can.BlackbirdHave you blown out the gun, checked the liner, and o rings?Disclaimer; "I am just an a$$hole welder, don't take it personally ."
Reply:This happened to me once on my Millermatic. It wound up being that the gun wasn't quite shoved into place far enough, down by the wire feeder. Go take the back end of the gun loose (on mine it's some kind of pinch bolt arrangement) and see if you can shove it in any more.For sure you aren't getting shielding gas.
Reply:when you put the torch down was it somewhere that the gas line was sitting on hot metal and got a hole melted in it - so it sucks air in?
Reply:Ive checked to make sure the gun is installed in the machine all the way, and it appears to be in as far as it can go, or atleast as far in as its ever been when it was working fine.I dont believe i rested the gun on anything hot to create a hole or anything, i always rest the torch on my cable rack when im not welding. Im not sure if i should try a whole new torch setup for this machine, or just take it to a local repair shop and get it looked at.  I need it back up and running asap obviously so i can continue work.I let the machine sit over night, and turned it on this morning to check it again.  initially it struck an arc fine and produced a good spot weld... then another.  so i clamped it on the axle and got ready to go at it again and get the job finished... it welded good for about 1/2" then everything turned to **** again, immediately porous.  Let it sit all day, tried it again, still instantly porosity .....Taylor
Reply:IMO, the pictures clearly show not getting any shielding gas cover.Turn off the gas at the tank, weld, I'll bet your welds looks the same.I strongly suspect you have a gas leak before the nozzle and zip-all gas is actually coming out of the nozzle to shield your weld.  e.g. You hear the gas but it's not coming out the nozzle.You say you hear gas but can you feel it?(Open the wire feeder so you don't spew out wire.)Check if gas is really coming out of the nozzle.  Dip the tip of the nozzle into a glass of water and pull the trigger.  Do you see lots of gas bubbles?  My bet is you see little.Also, not too likely but you can also check to see if you really have argon or an argon/CO2 mix instead of air.  Use an empty glass or tin can with a candle burning inside.  Put your nozzle over the can and pull the trigger.  The argon/CO2 should quickly extinguish the flame.  If not, and you passed the previous bubble test, then you got a tank of compressed air.  Given the fact that you welder starting working again for a brief period, I doubt you have this problem.These are three quick tests that should set you on the right track to solving your problem.Good Luck!Rick V 1 Airco Heliwelder 3A/DDR3 CTC 70/90 amp Stick/Tig Inverters in Parallel1 Lincoln MIG PAK 151 Oxy-Acet
Reply:It also just struck me as a possible problem with the electronics. What if his machine is no longer producing DC? AC output due to a filter cap that opened up or some such thing.BTW Rick, I think he mentioned earlier that he switched to a tank of straight Argon and had the same results.Lincoln Idealarc 250 (circa 1962)Lincoln Weldpak 155 w/Mig KitLincoln Squarewave TIG 175
Reply:Originally Posted by papaharley03It also just struck me as a possible problem with the electronics. What if his machine is no longer producing DC? AC output due to a filter cap that opened up or some such thing.
Reply:Originally Posted by weldermickwhen you put the torch down was it somewhere that the gas line was sitting on hot metal and got a hole melted in it - so it sucks air in?
Reply:Lincoln has tech support, look at your owner's manual it's on it. There is also a trouble shooting guide that might help. The black around the weld shows air is getting to the arc.porosity is caused by one of two things, improper gas coverage and contaminated metal.Gas should only be coming out two places, A small amount at the wire side of the drive and at the gun end, Check the gas hose from the regulator to the welder. Spray it down with something that bubbles and check for leaks. Then work your way out the the gun end.Good luck.
Reply:Well, the post about sticking the nozle under some water to see if its producing actual bubbles sealed the deal for me.Went out first thing this morning, and did that.  Right away, i had bubbles flowing everywhere, so i knew i was getting gas.  So, i started welding.  Welded for about 5 inches on a 10" length, and it **** out on me again.  stuck the nozzle under the water... no bubbles...Removed the gun, and liner and found that a fray from my liner had punctured by gas sleeve in the gun.  so when welding at some angles, it worked fine, with no problems.  then when i moved the cable around to re-position, it was leaking, and not working properly.just purchased a upgraded complete torch gun setup, and now im back to welding again.Thank you all very much for helping me trouble shoot my way through this.  I honestly was not suspecting this would be the issue.  i figured my gas valve inside my machine had gone bad, and wasn't letting enough shielding gas out.I appreciate all the help!Taylor
Reply:I had a heliarc that did that one time and eventually we traced it to a hose leak right inside the handle. I never could figure out how air would go into a hose with gas under pressure on the inside. But that cured the problem.  Mac
Reply:Originally Posted by Tool Maker I never could figure out how air would go into a hose with gas under pressure on the inside.
Reply:Originally Posted by JeebusWell, the post about sticking the nozle under some water to see if its producing actual bubbles sealed the deal for me.Went out first thing this morning, and did that.  Right away, i had bubbles flowing everywhere, so i knew i was getting gas.  So, i started welding.  Welded for about 5 inches on a 10" length, and it **** out on me again.  stuck the nozzle under the water... no bubbles...Removed the gun, and liner and found that a fray from my liner had punctured by gas sleeve in the gun.  so when welding at some angles, it worked fine, with no problems.  then when i moved the cable around to re-position, it was leaking, and not working properly.just purchased a upgraded complete torch gun setup, and now im back to welding again.Thank you all very much for helping me trouble shoot my way through this.  I honestly was not suspecting this would be the issue.  i figured my gas valve inside my machine had gone bad, and wasn't letting enough shielding gas out.I appreciate all the help!Taylor
Reply:Originally Posted by Rick VCheck if gas is really coming out of the nozzle.  Dip the tip of the nozzle into a glass of water and pull the trigger.  Do you see lots of gas bubbles?  My bet is you see little.