?? SA 200 commentator brushes arc. ??

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Seems on all my SA 200s, the commentator brushes are moving in and out.   But It hasn't been a problem until now on one of them.  The brushes are arcing a little on the commentator.    If I were to put an indicator on the shaft and turn it, It would appear the shaft is bent and running out.    I've always heard the way to straighten them, is take the commetator off, and put a pipe over the shaft, and bend it the direction it needs to go.    Well logically it makes sense, I'm just having a hard time working up the courage to start doing it.   Has anyone had any experience with this.   If so please describe how much force you used, and what kind of runout did you start and end up w/, did it last, etc. ??Also, how do these shafts get bent in the first place?
Reply:That is a pretty common thing on the SA 200. All of the ones I ran did it to a small extent. Running a cleaning stick once in awhile will help with the sparking. It also smoothes out the arc.
Reply:The commentator is clean, brushes moving freely w/ new springs.    Brushes lose contact every revolution the shaft makes.     The shaft is bent and turning fast enough to where the high point pushes brush out, then in half a revolution the brush is facing the low surface point of commentator.    The brushes can't return fast enough to keep contact in that 1/2 revolution.    It loses contact, and probally makes contact again at about 2/3 revolution.      It arcs each time it loses contact.    I'm thinking that arcing every revolution isn't helping the life of my commentator any.     The welding arc is already very smooth.    It's a 1956, it welds nicer than my redface even.    So I'm refraining from using it till I can figure something out here.
Reply:Those old machines were very smooth welding pieces of equipment. I owned one and when it finally gave up the ghost I really missed it until I got used to the one that replaced it. Your shaft must have a really bad bend if the brushes can't keep up with the rotation. I would straighten it.
Reply:Yep.  Straighten it as Oldtimer says using the method you described.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!