Bad Vibrations

[wpawa]

Hello everyone.
I need some help. my lathe has developed a vibration in the head stock. i thought i had bent my pen mandrel so i ordered another one. while i am waiting on the shipment i started doing some bowls and noticed i still have the vibration. my lathe is a German made Holtzstar and has been used heavily for 2 years now. i do have some noise in the bearings and the motor but its not "that bad" how do i know if a bearing needs to be replaced? can adjustments be made to eliminate the vibration?
Thank you all!
Will

 

[Dan Hintz]

If you have bearing noise and vibration, it's very likely you're about to have one go "all the way" bad (either seize completely or just fall apart).

Is the vibration in the headstock itself, or just the motor? Remove the belt and run the motor... does the vibration disappear? If so, it's the headstock. Find your manual and look at the assembly pictorial view to determine how to get the spindle out of there and replace the bearings. It may be easier on some models to let a machine shop swap them out for you. The bearings won't cost you more than a few bucks a piece, but the machine shop may charge a handful of dollars.

If it's the motor that vibrates, same general scenario, but it may be easier to take that to a rebuild shop... they won't be rebuilding the windings, but they're set up to rebuild the shaft/bearings on most any motor already.

Do not continue to use the lathe with heavy objects if it's vibrating... if the bearings are giving up the ghost, you can seriously score the spindle or the internal raceways (and that last one will require a trip to the machine shop to repair).

 

[Jim Burr]

Replace the bearings and see if that worked. If not...move on to belt issues

 

[Curly]

Before you do anything beading wise, loosen off the belt and look to see if the pulley is tight on the shaft. You may only need to retighten the little grub screw with a hex wrench. Make sure the pulley hasn't shifted before tightening. If the pulley is tight and the belt is okay then it is the bearings.

 

[PenPal]

Using a foot long dowel held to the head stock etc you should hear through that the source or rumble and isolate where the problem is much like a stethescope effect.

Kind regards Peter.

 

[wpawa]

I pulled the belt off and powered on the motor. i can feel the vibration in the tool rest but there is less noise. spinning the spindle free hand there is a little noise towards the front bearing. I will look at the pulleys to see if they are lose... if not i guess its time to rebuild the motor and change some bearings.
thank you for all the suggestions.
Will

 

[wpawa]

Last night i pulled the head stock apart and checked the bearings. they were fine.... so it must be the motor bearings right... pulled the motor apart and was surprised to find a full dustpan worth of wood chips dust and other junk in the housing . I blew it out with a compressor and got even more dust out of it. wrote down all the part numbers to rebuild the thing thinking it would be toasted. I put it all back together and just for fun turned it back on. not only was 99% of the noise gone so was 99% of the vibrations. Just goes to show cleanliness is important. Not only did i get to learn how to rebuild my lathe i also came up with a cleaning schedule to prevent it from happening again.
Will