Undercut!

admin

Hello all I am new here.... I usually weld alot of beveled pipe so I usually don't have this trouble in my work, but today I was welding some mild steel channel and had a bit of trouble... I had it stacked on another plate and as i drew the righteous bead down the filet I stpped to admire my handywork and low and behold.... Undercut on vertical side!!!! God's sake.... I was using 7018 rod DC EP set at about 125 amps oh yeah 1/8 in rod....Any ideas??? too hot??? I think it has somethind to do with my angle...any help would be great..Thanks,Jeff
Reply:Sounds like the amperage was set OK.What you describe has more to do with rod angle.Try a 45* or less angle to the joint.(think I said that correctly)
Reply:Two ways to melt out that vertical face: If your angle is too low then the arc force hits the vertical face concentrating the heat above and the metal rolls down.  The other way is if the rod is too high the arc force gouges out the vertical face each time you move the rod closer to the vertical.   45 degrees is good.  Also keep the 45 and aim the rod about one diameter closer toward you than to the vertical face.  Point the the rod back about ten degrees and concentrate on watching the back end of the puddle as it cools.  Gee, I don't know how I know so much about undercut?  Strange! :')
Reply:Lotech,You know soooo much from watching other's mistakes...that's a good story...I use it often...that is when I actually know something.Smithboy...if it ain't broke, you ain't tryin'.