CWB GMAW flat- push or pull

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I have taken the CWB test for flat twice now with bad results, im using the pull technique, cause the schools instructor told me it would work better on this test, im not to sure now cause i feel like its causing me to fail. I have been welding MIG for 7 years now and never have i used this pull techniqueI need some advice on how to pass this test.
Reply:What is the base metal type and thickness, filler metal, and joint preparation you're using for this test?Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:The CWB test is 3/8" plate with a bevel on one side and a square edge on the other with a 13mm gap in between with a backing strip.  (if I recall correctly).   Push or pull you should be able to pass with either method.   I did 2 in school for practice and had no cracks and welded them both ways.Pushing gives less penetration and pulling gives more (if you are using the same settings).  So where is it breaking ?  the face or the root ? both ?  Run your root passes hot !!!!   Your probably breaking on your starts and stops im guessing ?   Oh and if you are more comfortable pushing go ahead thats how I run GMAW I just turn the heat up to make up for the lack of penetration....   I find I can see better pushing....Last edited by Newfie_1986; 06-12-2009 at 12:43 PM.
Reply:I took the 3g and turned  the machine down for each pass of 3.  The plate gets warm and the weave gets wider with each pass.  I think I started at 165 ipm and 18.5 volts. Straight Co2.  .045 S-6 wire.David Real world weldin.  When I grow up I want to be a tig weldor.
Reply:One of the problems with welding flat with a semi auto process such as GMAW is the possibility of carrying too much weld metal for the amount of energy you are running. As the puddle becomes too large, all of the heat is used "superheating" the molten metal but does not get a chance to melt the underlying base metal. Regardless of push or pull, stay on the leading edge of the puddle.Travel speeds that are TOO SLOW can cause fusion related defects with either pushing or pulling. The advantage to pulling (I think) is that it keeps much more of the molten metal pushed back and not directly under the arc.Though a slower travel speed may "heat up" the base metal more, its done from the energy thats transferred away from the large amount of molten weld as opposed to energy from the arc.My opinion only based on things I have read and seen.Have a nice dayhttp://www.weldingdata.com/
Reply:Thanks Newfie.  There's not much more I'd add to what Gaustin and the others have already said.Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:Thanks for the info, next time i take this test i am going to push but i will turn up the heat to about 24 - 25
Reply:Originally Posted by Newfie_1986The CWB test is 3/8" plate with a bevel on one side and a square edge on the other with a 13mm gap in between with a backing strip.  (if I recall correctly).
Reply:you guys run a 3/8" backing plate ?  Ours was only 1/4" ...Here I found something on it..http://www.grbwelding.com/images/CWBTest.pdfLast edited by Newfie_1986; 06-12-2009 at 11:12 PM.
Reply:Oh, sorry, my response was for GMAW.  I see you are discussing SMAW.  My mistakeGordie -- "I believe you understand what you think I said, but I'm not sure you realize that what you heard is not what I meant."
Reply:Nope my mistake lol   I gave the wrong dimensions.   Hes talking about gmaw.  I didnt even notice that test procedure was for SMAW.   It was a long day at work,  time to go catch some sleep.
Reply:For the flat position in school we used true spray transfer, what type of gas and wire do they have u using? do the fillet weld first then do the groove side second, but dont fill in the crater at the stop and starts or else it will make a cold spot. fill until u leave a small amount of the top edge of the joint showing, but not too much or else u wont fill it properly.layer the cap with overlaping beads starting furthest away from you and work your way in.Nothing Ever Got Done By Quitting, Never Give Up.