Bad rod or bad welding

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Last week I was practicing with 7018,it was coming out REALLY  well.Today not so well.Aside from undercutting and inconsistant travel speed(my fault)there are holes in the weld.Is this porosity or just bad welding?There doesn't appear to be any slag in the holes.I've had rod for about 2 months and don't have an oven.The rod has been kept in one of those plastic tubes with the screw on gasketed lids. Attached ImagesMiller a/c-d/c Thunderbolt XLMillermatic 180 Purox O/ASmith Littletorch O/AHobart Champion Elite
Reply:It could go either way, I have used rods that have been outside an oven longer than that with no SURFACE porosity.  I have also used rods straight from the oven and gotten porosity.You could also be holding to tight or too long of an arc gap, but its impossible to tell what your problem is from that picture.I would get a few pounds of fresh rods and try that and see what happens.Have we all gone mad?
Reply:Originally Posted by sn0border88It could go either way, I have used rods that have been outside an oven longer than that with no SURFACE porosity.  I have also used rods straight from the oven and gotten porosity.You could also be holding to tight or too long of an arc gap, but its impossible to tell what your problem is from that picture.I would get a few pounds of fresh rods and try that and see what happens.
Reply:Another potential cause for porosity is contamination. Is the plate clean? Is it covered in rust from sitting outside? It dosn't take much to cause a problem in certain conditions.ScottWelders360New guy.
Reply:Zapster-Its 1/8 7018ac rod(Ibought ac accidentilly).I'm running 110 amps,electrode positive.I tried using elctrode neg.Everything was the same as last week,when welds turned out so well.Yes I was practicing for welding shaft.Scot-steel was not rusty ,fairly clean.Miller a/c-d/c Thunderbolt XLMillermatic 180 Purox O/ASmith Littletorch O/AHobart Champion Elite
Reply:If you're running 7018AC, RUN IT ON ACIt will give you a good bead, different, but a good beadTurn the machine up to around 135amps, and let it burnsome pics of 7018Ac to follow, if I can dig them upPorosity can be, like others said, a function of too long an arc.  Don't immediately think it's "wet" rods."Any day above ground is a good day"http://www.farmersamm.com/
Reply:I agree with sam (not only because he is a much better welder than I but also because I love that cow in his pic!)HAHAI always run that rod at 135A and never get porosity in welds unless its on a cold start which is attributed to my bad user error.  I think from the pics you must be running it too cold.  You dont have enough arc force to blow the crap out of the pool which is giving you what you see.  Also if its AC rod run in on AC because thats what it was designed to run on.
Reply:I just now tried using it with ac 135 amps.seemed to work better.I'll try it on a groove or filletlater.I had been successfully using that rod with dc.Miller a/c-d/c Thunderbolt XLMillermatic 180 Purox O/ASmith Littletorch O/AHobart Champion Elite
Reply:AC rods will run just fine on DC. They just have more stabilizers in the flux to work better on AC...mainly the small AC Tombstones and units like that. The stabilizers don't do anything to hurt DC performance.If the 135a worked better, I'd say its possible you have a little moisture contamination. The higher amperage was able to overcome it. Running an 1/8...assuming 1/8 anyway....rod on 110a is kinda on the low side anyway. Fresh rods will make it easier, but once they get the moisture in them, the lower amperage will start biting you in the backside.QamuIs Heg qaq law' lorvIs yInqaq puS
Reply:Don, aka DDA52 is the guru of stick.Well, one of the guru's.  And most importantly..........my mentorIf he says it'll run good on DC, I gotta believe it.  Never did try to run it on DC.But when it comes to arc blow.............AC RULES Wrap the leads around the iron, put the clamp everywhere, including yer johnson, nothing beats blow like AC.  NOTHINGPic...........very bad arc blow situation, everything but standing on my head, feet pointed south, nose pointed east, feet firmly planted on the ground.  Nothing worked.  AC SAVED THE DAY  Not perfect, but a stable arc. Attached Images"Any day above ground is a good day"http://www.farmersamm.com/
Reply:I'm not a guru Sam. No way am I gonna sit on a mountain top all day long. That has to hurt.Actually, you did use AC rods Sam. The 3/32's I had you weld with were 7018-AC. You never even knew the difference.QamuIs Heg qaq law' lorvIs yInqaq puS
Reply:From what I have learned is that the 7018 is a low hydrogen rod, that when exposed to air absorbs hydrogen and humidity. Which in turn makes for a poor weld. We always tried to use an oven to keep the 7018 warm, I don't remember the temp. So if your welds were good with freshly opened rod, and after the rod sat for a while, the welds kinda turned to "crap". You may want to try finding an old rod oven. Don't use the oven in the kitchen. We had an old fridge with a heat lamp in it at the shop for keeping rod in. Just a couple of suggestions.Nothing is fool-proof, to the substantially talented fool!Help me, I can't drink all of this beer myself.
Reply:7018 is only good for 4 hours after being opened per AWS specs then needs to go in rod oven cuz it absorbs moisture fast.Tiger Sales:  AHP Distributor    www.tigersalesco.comAHP200x; AHP 160ST; MM350P,  Spoolmatic 30A; Everlast PowerTig 185; Thermal Dynamics 60i plasma.  For Sale:  Cobra Mig 250 w/ Push-pull gun.  Lincoln Wirematic 250
Reply:Thanks for the clarification, been awhile since I used 7018. Guys at my new job just can't understand about the differences in welding rod. Alot of the "We've been doing it this way for 30 years" mentality. So I don't even touch the 7018 that has been sitting out for years.Nothing is fool-proof, to the substantially talented fool!Help me, I can't drink all of this beer myself.
Reply:Cranking current up helped.Top weld is 7018 dc en 125 amps.Not perfect but closer to what I was doing before. Attached ImagesMiller a/c-d/c Thunderbolt XLMillermatic 180 Purox O/ASmith Littletorch O/AHobart Champion Elite
Reply:Try 135.QamuIs Heg qaq law' lorvIs yInqaq puS