Guess I get to try the 7018 rod bake procedure!

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Ok, today marks my second day of employment at my new job - Welding and Joining Technology Instructor at a local community college.  As I'm going through to inventory the stuff we have so I can make up a order I have come across a total of 7 open 50lb tins of Hobart 1/8" 7018 electrodes.  Out of those seven boxes there is about 20lbs of rod used.  Most of the tins have the tab pulled a couple of inches as if someone didn't believe the label on the tin and wanted to see if the numbers on the rods matched!  I know these have been open at least a year....  Sitting on the damp concrete floor in a non-climate controlled shop...  How could this happen at a school?The best part is there is a pretty good sized rod oven not far away sitting at around 200 degrees with a handful of mostly 6010 in it.So, I'm going to expirament a little and see if a good bake makes a noticable difference.  We have a machine tool program here as well, and they have a pair of good sized heat treat ovens, so we'll see if a few hours at 750 or 800 helps any.
Reply:Sitting on the damp concrete floor in a non-climate controlled shop... How could this happen at a school?
Reply:http://www.hobartbrothers.com/pdf/su...rage_Chart.pdfLast edited by A_DAB_will_do; 04-02-2009 at 03:21 PM.Reason: drat, wrong link...Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:Thanks Dab - that's a nice, concise chart.  Oldiron - I'm not going to keep the 6010 in the oven; just the 7018 after the 750 degree recondition bake.
Reply:I would like to see this too.A_DAB_will_do, your chart is bookmarked thank you.David Last edited by David R; 04-02-2009 at 04:28 PM.Real world weldin.  When I grow up I want to be a tig weldor.
Reply:Good find on the rebake chart A_DAB.  Also, TubularFab, double-check that the oven can do rebake.  Some ovens are just storage ones and can't get up to rebake temp.And as the chart says, 6010 is supposed to be at room temp and humidity and NOT in an oven.Rebake is supposed to be done with the rods taken out of the can and spread out so that all of the rods and their coating can reach oven temperature and dry out properly.Lincoln calls out a bit more specifics on their low-hydrogen and specifically their 7018 store and rebake specs.  For 7018 exposed to high humidity (Hmmm, Georgia anyone?   ) or atmosphere for greater than one week, they recommend a dry-out pre-bake at 180-220F for 1-2 hours to minimize coating cracks or alloy oxidation and then a bake time/temp of 1 hour at 650-750F.  If the coating flakes or breaks off after the rebake, the electrode is supposed to be scrapped/tossed/junked.  Similarly if the weld or arc isn't 'right' after the bake.Lincoln also says that 6010 is supposed to be stored at room temp or in a barely heated cabinet at 100-120F and that higher temperatures will most likely damage the electrodes (more specifically the coatings).  They even issue that warning in itallicized BOLD print.Lincoln document c210, "Stick Electrode Catalog".  Available as a PDF online from http://www.lincolnelectric.com/products/litrequest/  The best laid schemes ... Gang oft agley ...