small lathe vibration

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Got a vibration on my small logan/MW 9x36. It's your single phase motor driven 3 speed pulley/3 speed spindle setup.I checked the motor runout and it's about 0.001"... Good. Spindle runout < 0.001". GoodAs soon as I fasten the pulley on the motor shaft the runout is so bad I can see it with my naked eye. Seems like this is getting transferred to the cut.Is it time for a different pulley, of do I need to pull the motor off and tap the pulley around until it runs true? That could take a LONG time.ESAB Heliarc 252
Reply:sounds like the pully is not good, and needs replacement,
Reply:A steel "turned" pulley verses a "pot metal" cast pulley.Steel vibrates less.A GOOD drive belt is a necessity.In the old days, they called it a cut belt meaning the sides were equi-distant like the old Vee belts in a car verses a lap belt that was just layers layed together, consequently tending to ride up and down in a pulley causing vibration.
Reply:If it runs out that bad when tightened up..I am assuming a set screw on top of the key..The shaft or the pulley bore is worn out pretty good..Either and or both need to be addressed......zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Originally Posted by BlauSchuhGot a vibration on my small logan/MW 9x36. It's your single phase motor driven 3 speed pulley/3 speed spindle setup.I checked the motor runout and it's about 0.001"... Good. Spindle runout < 0.001". GoodAs soon as I fasten the pulley on the motor shaft the runout is so bad I can see it with my naked eye. Seems like this is getting transferred to the cut.Is it time for a different pulley, of do I need to pull the motor off and tap the pulley around until it runs true? That could take a LONG time.
Reply:I have a 12X36 lathe from grizzly and it started making a pattern in the finish of the work after I rearranged the shop. After I checked to make sure everything was tight, and everything was, I realized that the marks were caused by some kind of harmonic oscillations that the machine was creating. By chance loosening up one of the motor mounts fixed it. I thought it was a pretty strange thing to happen and i wasnt sure how to fix it. I only found the solution by chance. Maybe there's something like that going on..
Reply:Originally Posted by zapsterIf it runs out that bad when tightened up..I am assuming a set screw on top of the key..The shaft or the pulley bore is worn out pretty good..Either and or both need to be addressed......zap!