New Eye on Excavator Attachment/Cluster Porosity

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Excavator attachment I rebuilt a couple of weeks ago.  Gives a good visual of cluster porosity on the starts using 7018 by the welding/machine shop that built it originally.  New eye is 2" A514 (T1) welded using Hobart FabCo 110 1/16". Attached Images
Reply:That is the problem, they should have upgraded to a Harbor Freight welder. http://www.harborfreight.com/225-amp...der-69029.htmlSee this is 225 amps @ 20 % duty cycle. They must have spend 10 months making that weld.
Reply:Originally Posted by BD1That is the problem, they should have upgraded to a Harbor Freight welder. http://www.harborfreight.com/225-amp...der-69029.htmlSee this is 225 amps @ 20 % duty cycle. They must have spend 10 months making that weld.
Reply:Nice repair. That clearly saw some hard service despite the defect. What do you figure the cause was? Just sloppy starts?
Reply:I looked it up since I had not heard it referred to as cluster porosity before.On a radiograph website I found this:https://www.nde-ed.org/EducationReso...raphInterp.htmDave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:Originally Posted by forhireNice repair. That clearly saw some hard service despite the defect. What do you figure the cause was? Just sloppy starts?
Reply:Originally Posted by MinnesotaDaveI looked it up since I had not heard it referred to as cluster porosity before.On a radiograph website I found this:https://www.nde-ed.org/EducationReso...raphInterp.htm
Reply:Thanks for the tip and I will keep an eye open for it. Your welding sure looks excellent btw  Have to say, I've never welded a piece so thick that it took 6 hours to complete - whole darn thing had to be hot by the time it was done.Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:Well that's a bigger lifting eye than what I put on our excavator...Airco Ac/Dc 300 HeliwelderMillerMatic 200 (stolen)Miller Maxstar 150STLMiller AEAD200LE (welding and generating power) Hobart MIG
Reply:How many pounds of rod was that?It would been cool to see a time lapse video of that being welded up.
Reply:With the original hole in the padeye being so deformed, I can see why they went with much thicker plate. We generally add donut washers to each side of our padeyes, Attached ImagesDon’t pay any attention to meI’m just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:The old school Navy technique for stick welding starts when you were welding on something super critical (like submarine pressure hull) and couldn't afford to take the chance you'd have any thing at all (porosity, lack of fusion, trapped slag, etc.) wrong with them was to do what we called "piggy-backing" them.   You'd strike up a 1/2 to 1 inch back on top the bead you'd just laid so that by the time you got to the stop of the previous rod you were trying to continue on from the new rod was up to temp and burning smoothly.  And then you'd go back and grind off that hump that was your start before putting the next layer over it.   Grinding every start off was basically just an insurance policy we used to insure we got water clear x-rays.
Reply:Was the rebuild a result of weld failure, or just a worn out eye?"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Originally Posted by farmersammWas the rebuild a result of weld failure, or just a worn out eye?
Reply:Originally Posted by HT2-4956The old school Navy technique for stick welding starts when you were welding on something super critical (like submarine pressure hull) and couldn't afford to take the chance you'd have any thing at all (porosity, lack of fusion, trapped slag, etc.) wrong with them was to do what we called "piggy-backing" them.   You'd strike up a 1/2 to 1 inch back on top the bead you'd just laid so that by the time you got to the stop of the previous rod you were trying to continue on from the new rod was up to temp and burning smoothly.  And then you'd go back and grind off that hump that was your start before putting the next layer over it.   Grinding every start off was basically just an insurance policy we used to insure we got water clear x-rays.
Reply:Originally Posted by gator9329How many pounds of rod was that?It would been cool to see a time lapse video of that being welded up.
Reply:Nice repair! I am a welder for an underground company as well. Nothing like burning on the big stuff. I will be welding on some 2" plate next week putting new ears on a 10yard backfill bucket. Cheers!
Reply:The other big trick for avoiding cluster porosity building up in an area is to stagger your stops and starts.  Especially the starts since they're more prone to having porosity in them.   I know that outside corner when you're welding a pad eye on seems like a natural start and stopping point but when ever possible you should make the turn and weld thru it, even if only for a couple of inches past it.   That way you won't end up with all your starts stacked up on the corners.   This will also give you much smoother looking corners once you get use to doing it.Last edited by HT2-4956; 10-16-2014 at 10:28 AM.
Reply:https://plus.google.com/118042565834...ts/jkqGCWWqhBCThanks for all the compliments and insight.  It helps us all learn. Here is a video of them using this attachment