re-welding...question on going back over a weld

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This is my first post...so let me just say "Hello" first!  I wouldn't call my self and expert welder by any stretch of the imagination, but I'm not a beginner either.  I was a machinist for 3 years in school then 2 years in the work force, but mostly I cut metal...not put it back together.  This is a great site, I've been lurking and reading for a while...and now have a question.I'm in the process of shortening a rear.  I'm using a Lincoln PRO MIG 180...with .035 wire.  The rear is about 3/16" thick tubing.  I got a new spool of wire that had a "loop" in it that kept interrupting the wire feed.  So on one end I had to start/stop 4 or 5 times while welding.I felt initially like I burned it in fairly well, but as I sat last night thinking about it...I'm starting to second guess myself.I was thinking of putting the jig back on it (I use a 1.5" bar with machined "collars" to hold everything straight), grinding into the weld with an angle grinder and going over it again.Thoughts?  Should I leave it alone or should I grind into it and make another pass over it?THANKS!
Reply:If you're going to grind it, grind it all out and reweld, don't just go half way and put another pass on top of it.
Reply:If the feeling in your gut is telling you to grind it out, then you should go ahead and grind it out.  Listen to that little voice inside you, it knows the right thing to do.Mig is always a cold start.  If  you started and stopped several times going around the pipe, you probly have several cold (weak, poor penetration, poor fusion) spots in the weld.  Reason enough to grind it out.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:That's exactly what I did tonight.  I ground out ALL the weld, and went at it.I feel much better now, and the welds are much much better this time.thanks for the advice!!!!
Reply:Hey glad it came out good for you, thats great!  MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op