mig welding rims

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I am welding rims in a jig.  There is a rotator on the jig and the process is going well.  We are using a Miller 304 cc/cv with pulse.  I have used different cover gases as well as wire.  The problem is this.  The weld has a bulge in the middle that I want flat.  How do you do this?  I just want to take the weld to a flat level with no undercut on the edgesThanksJohn
Reply:Well, now, I'm no rim welder.  In fact, it seems that if you have to ask questions on how best to do it, you probably shouldn't be welding rims.  The "bulge" is called "reinforcement."  So, your question is about removing the weld's reinforcement on a pressure vessel.  This can be done sometimes for the elimination of stress risers or other aesthetic reasons when there is sufficient strength inherent in the joint already.  I know rim welding is done by experts and only in certain applications, so I'm not saying don't do it.  I just hope you really do get it done right, and make sure it's legal and safe.
Reply:I worked for a company that made rims.... Beeg ones for ore trucks down to regular truck size.  The position of your gun and the location of your puddle has everything to do with it.  You want to weld so that the puddle freezes at top dead center if you are welding on the outside or bottom dead center if you are welding on the inside.   If you are welding on the inside move further ahead up the incline to pile up the bead.  Move closer to the bottom to cause the bead to flatten.   I hope I got it right ... It has been awhile.  You will have to experiment a bit.  On something like a 24 inch rime moving an inch along the seam will make a noticeable difference.
Reply:I would put the weld in a variing downhill position till I found what worked.David