Pinholes in weld

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This afternoon I finally got my Lincoln Migpak 180 all hooked up and running.  I'll be the first to admit that I'm not a pro welder, but I have mig welded enough in the past to know that I must be doing something wrong here.  I began by just doing some spot welds on some sheet metal.  I played around with the wire speed and heat settings, but no matter what I do, I seem to be getting these tiny pinholes in my beads.  Regardless of what I try for settings, the result seems to be the same everytime.  I ground down the area to be welded with a flapper disc but did not wipe it down because it was on clean dry steel with just light surface rust.  I also made sure the area where my ground was connected was ground down as well.  I'm using Argoshield Light & I've tried gas settings anywhere from 20-45 on the guage but nothing's changed.  I double checked the polarity as well and it seems to be correct.  Am I missing something obvious here?
Reply:Porosity is usually related to three things: Shielding gas (too much or not enough), Part contamination, or Filler Metal contamination. If weld is clean on surface, and you have small pore porosity, I'd lean towards part contamination. If weld is clean, but has large pore porosity, that can indicate too much gas. If weld is gray or dirty, that can indicate not enough shielding gas.What filler metal are you using? Does it have any surface rust on it? A few other things to consider are gun angle, and nozzle distance from the workpiece. If you are pushing (working right to left) your gun should be angled approx 10 degrees to the right. Nozzle distance should be approx 1/4"-3/8" Since your material is clean, I'd look towards the filler metal, gun angle and stickout.
Reply:As far as filler material is concerned, I'm kind of new to this so I'm assuming you're talking about what wire I'm using.  I'm using the Lincoln .025" roll that came with it.  I am about 1/4"-3/8" away at a slight angle.
Reply:Are you out of the wind?City of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:Originally Posted by tanglediverAre you out of the wind?
Reply:It sounds to me like you have no shielding gas.You could try turning the gas off and see if there is any difference - if no difference, you are not getting shielding gas.Alternatively, I suggest that you make certain you have gas flow at the nozzle."Gas settings anywhere from 20-45 on the guage" means you have pressure in the line to the welder but is the gas solenoid working, letting the gas through to the nozzle?  You can check that by releasing the tension on the wire feeder so that when you pull the trigger no wire comes out the gun nozzel.  Stick the nozzle close to your ear, when you pul the trigger can you hear the rush of gas?Rick V 1 Airco Heliwelder 3A/DDR3 CTC 70/90 amp Stick/Tig Inverters in Parallel1 Lincoln MIG PAK 151 Oxy-Acet
Reply:Originally Posted by FixxxrNo, I'm in the garage with the door shut.
Reply:Originally Posted by Rick VIt sounds to me like you have no shielding gas.You could try turning the gas off and see if there is any difference - if no difference, you are not getting shielding gas.Alternatively, I suggest that you make certain you have gas flow at the nozzle."Gas settings anywhere from 20-45 on the guage" means you have pressure in the line to the welder but is the gas solenoid working, letting the gas through to the nozzle?  You can check that by releasing the tension on the wire feeder so that when you pull the trigger no wire comes out the gun nozzel.  Stick the nozzle close to your ear, when you pul the trigger can you hear the rush of gas?
Reply:Originally Posted by tanglediverOK, you have 0.25 wire, solid, I presume. Clean, shiny, filler wire is the best, and you can get wipers for your filler wire that can be lubricated with a solvent to help keep dust at bay. Is your shielding gas 75% Argon and 25% CO2? 20 cubic feet per hour should work, 15 is ok as well, above that is a waste and risks introducing air by turbulence. 45 CFH is way too much. Yes, I have used as much as 35, but it was not my gas, and I was outside in the breeze. So, you have clean, shiny metal right? You keep a close stick-out of a constant 1/4" and close to 90 degrees perpendicular to the direction of travel, right? You can lean to push or pull or off to the side a little bit so you can see under the gas nozzle, that's fine, just don't get extreme. You can strike a puddle ok, yes? Do that and LEAD THE PUDDLE. It will follow the arc, do not wait for the puddle, but don't run away from it. Take you time and relax, you will recognize your own mistakes with enough practice.Post pictures and we can give you some more detailed help.
Reply:I'd go back to what ss42768 said, "If weld is gray or dirty, that can indicate not enough shielding gas."  When I run out of shielding gas (CO2 in my case), the arc sounds different and the weld goes from smooth and silver-shiny to dull grey and full of porosity (gas pin holes).If you do have gas flow (can you hear it?), clean metal and clean wire - that really leaves only your gas.  You said you were using "Argoshield Light".  Maybe you got a contaminated bottle of gas?  Can you try another bottle of gas?Rick V 1 Airco Heliwelder 3A/DDR3 CTC 70/90 amp Stick/Tig Inverters in Parallel1 Lincoln MIG PAK 151 Oxy-Acet
Reply:Originally Posted by Rick VI'd go back to what ss42768 said, "If weld is gray or dirty, that can indicate not enough shielding gas."  When I run out of shielding gas (CO2 in my case), the arc sounds different and the weld goes from smooth and silver-shiny to dull grey and full of porosity (gas pin holes).If you do have gas flow (can you hear it?), clean metal and clean wire - that really leaves only your gas.  You said you were using "Argoshield Light".  Maybe you got a contaminated bottle of gas?  Can you try another bottle of gas?
Reply:http://www.lincolnelectric.com/knowl...ent/migfaq.asphttp://www.mig-welding.co.uk/welding-gas.htmToo much gas flow, methinks.City of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:why would you use such a high argon percentage on steel, i prefer 100 co2, 75 argon is ok, but i don't like 100 argon on steel.Dynasty 200DXPassport plus w/ spoolmate 100victor 315c oxy/(act and prop)Miller digital elitemilwaukee power tools
Reply:Is your gun set to reverse (+) polarity?  Wrong polarity can be the issue.Esab Migmaster 250Lincoln SA 200Lincoln Ranger 8Smith Oxy Fuel setupEverlast PowerPlasma 80Everlast Power iMIG 160Everlast Power iMIG 205 Everlast Power iMIG 140EEverlast PowerARC 300Everlast PowerARC 140STEverlast PowerTIG 255EXT
Reply:Originally Posted by turkwhy would you use such a high argon percentage on steel, i prefer 100 co2, 75 argon is ok, but i don't like 100 argon on steel.
Reply:The other things you may want to check are the gas regulator diaphram to make sure it doesn't have a tear or hole in it, all the gas line connections are tight, the guns liner to make sure it is a snug fit right to the end of the tip and that all the "O" rings are sealing. I rarely use more than 13 PSI argon flow.Miller Auto Invision 456 + S-62 wire feederC6240B1 Gap bed lathe16 ft3 air compressor16 speed pedestal drillHafco BS-912 Bandsaw
Reply:Originally Posted by Ed.The other things you may want to check are the gas regulator diaphram to make sure it doesn't have a tear or hole in it, all the gas line connections are tight, the guns liner to make sure it is a snug fit right to the end of the tip and that all the "O" rings are sealing. I rarely use more than 13 PSI argon flow.
Reply:I have come across this many times. One that had me going is, that it can be a cheap regulator. Instead of a flow meter with a steel ball. You can get one of the double gauge type flow meters because they throw them in for free. One of them caused us hours of trouble. The gas came on too strong and then died out. We usually use 15 cubic feet an hour on steel, Argon or Argon/Oxygen. If you move too slowly, you can also get this effect. If you boil the puddle too much you can get those holes. That is where I would put my money.Sometimes especially if the wire gauge is at its limit for heating the part, you tend to slow down, when you do slow down, you boil the puddle and you get those holes. I find I also reduce my attack angle when I don't have enough heat. So again you have the wire almost perpendicular to the part, causing boiling in the puddle, and then holes. Try more attack angle and move along a little faster, without waiting to see the puddle form. That is how we usually do it. But we are sure of the results so we can do that. You might have to try what I am saying to believe it. Are you pushing or pulling? I push only.        Sincerely,             William McCormick
Reply:Originally Posted by FixxxrI haven't had a chance to get out there and try it again today so hopefully tomorrow.  It may be a stupid question, but how do I check the regulator diaphragm..and what does it look like?  Also, I didn't know that too much gas could cause the weld to be porous, so I'm anxious to give that a try!
Reply:Originally Posted by ss42768Porosity is usually related to three things: Shielding gas (too much or not enough), Part contamination, or Filler Metal contamination. If weld is clean on surface, and you have small pore porosity, I'd lean towards part contamination. If weld is clean, but has large pore porosity, that can indicate too much gas. If weld is gray or dirty, that can indicate not enough shielding gas.What filler metal are you using? Does it have any surface rust on it? A few other things to consider are gun angle, and nozzle distance from the workpiece. If you are pushing (working right to left) your gun should be angled approx 10 degrees to the right. Nozzle distance should be approx 1/4"-3/8" Since your material is clean, I'd look towards the filler metal, gun angle and stickout.
Reply:PROBLEM SOLVED!!!So I finally got a chance tonight to head out to the garage and try a few things.  First off, I loosened off the wire feed to see if gas was actually coming out of the gun or not.  Guess what...no gas coming from the tip of the gun.  Next I tuned the gas off on the bottle and unscrewed the gas hose running to the back of the machine.  I realized the gas WAS getting to the machine...but where was I losing it?  Turns out that the hose for the gun wasn't fully locked into place and gas was escaping where the hose enters the machine in the front.  Come to think of it, I had a fight attaching that hose when I was setting it up - I guess I should've tried that sooner!Anyway, you live & you learn.  I'm now running at 15cfh and WOW do I have some beautiful spot welds!!
Reply:Originally Posted by FixxxrPROBLEM SOLVED!!!So I finally got a chance tonight to head out to the garage and try a few things.  First off, I loosened off the wire feed to see if gas was actually coming out of the gun or not.  Guess what...no gas coming from the tip of the gun.  Next I tuned the gas off on the bottle and unscrewed the gas hose running to the back of the machine.  I realized the gas WAS getting to the machine...but where was I losing it?  Turns out that the hose for the gun wasn't fully locked into place and gas was escaping where the hose enters the machine in the front.  Come to think of it, I had a fight attaching that hose when I was setting it up - I guess I should've tried that sooner!Anyway, you live & you learn.  I'm now running at 15cfh and WOW do I have some beautiful spot welds!!
Reply:I recently had an issue like this wear i would be running a bead then all the sudden get porosity. Couldn't figure it out. I was definately getting gas out of the nozzle. I ended up figuring out that the gun end came loose in machine and when I would get further away with gun it would pull slightly and cause the gas to not make it into hose. When I would go back and look at machine it would move back into connection and everything was fine. That was a tricky deal.Millermatic 252Lincoln 175 plusTA 185tswTA 161stlhypertherm pmax 45Victor torchHenrob torchAn S10 for each day of the week
Reply:Hey Fixxxr !  Nice to hear you solved your problem... by following my diagnostic steps of post #6.  You feel good; I feel good - finally got something right!  Rick V 1 Airco Heliwelder 3A/DDR3 CTC 70/90 amp Stick/Tig Inverters in Parallel1 Lincoln MIG PAK 151 Oxy-Acet
Reply:That is great post some pictures when you get it going.        Sincerely,             William McCormicki have been a welder for a very long time and have always considered myself very skilled i guess i m just having a bad day. nothing is seeming to work right. The fact that i have the best equipment money can buy (12k setup) it is that much more frustrating.I am running a volt sensing wire feed and a xmt 450 power pack. i have had problems with pin holes all day and im building a $500,000 machine. all the welds have to be pinhole free for quality requirements from the boss. it will be sandblasted painted blocked and sanded but good work now makes it better finish. my settings have been pretty consistent. I like to run hot and fast , as i am welding 1/8 sheet skin over a "shed" frame. working on the roof so way not comfortable and not in the best position (bad knees) gas is 75/25 c25 at 25-30cfm wire is .035 solid wire set at 289 in per min and 24.5 volts. I have gotten some good welds out of it but when i grind them down pin holes open up on the inside of the weld not the top. i did notice that the welds are dark grey and not particularly shiny. I am considering cutting a gap in the joint to make sure i get better penetration. anyway i think thats it i will go back to the drawing board and try to figure out another plan of attack...
Reply:I am just an amature dummy here so WTF do I know...   But when I see pinholes in my wire feed beads I have learned that I need to turn up the shielding gas or block the draft that is blowing it away, or clean the parent metal better to remove contamination.  Another old saw at MIG advised that a liner that has seen a lot of wire can introduce contaminents onto the wire which can cause that symptom.Millerwelds.com has a MIG troubleshooting guide:http://www.millerwelds.com/resources...-Defects-GMAW/First up is porosity and pinholes in steel welds, caused by inadequate shielding gas.- MondoMember, AWSLincoln ProMIG 140Lincoln AC TombstoneCraftsman Lathe 12 x 24 c1935Atlas MFC Horizontal MillCraftsman Commercial Lathe 12 x 36 c1970- - - I'll just keep on keepin' on.