need help, out of ideas,

[wizical]

Ok, i have ran into a problem with my woodturning today. I was making a Jr. Gent Retro Pen and it seemed that the pen was out of round. So when i turned it on slow speed, i noticed at the headstock end it was turning with a lot of vibration and out of round, but at the tailstock end, it was running fine. So i cleaned everything, checked to make sure that the headstock and tailstock lined up properly. I changed the bushings, changed the mandrel rod, I even tried using an adjustable mandrel to see if it could fix the problem, it still had bad vibration. I know nothing ever runs true, but there has to be something better. Does weather have an effect on how the mandrels work?

I have a jet mini Lathe, and a Jet JWL 1236, im getting ready to upgrade, but in the meantime i need this stuff to work,

i hope this is enough info to help me out, thanks

 

[TellicoTurning]

sounds like you might have some bad bearing in the headstock..

 

[desert1pocket]

I agree, sounds exactly like a bad bearing.

 

[wizical]

same problem with the mini lathe too, not as severe, but there is some vibration on the headstock side, same problem with the bearings?

 

[n7blw]

Can you check the runout with a dial indicator? I have less than 0.001 at the headstock on my nearly-new Jet 12x20 lathe. I was having problems with tailstock runout until I "tuned" the rotational position of the shaft in the collet in my PSI adjustable mandrel. With the tailstock removed, I get about 0.010-0.012 at the shaft end; with the tailstock in position and snugged up a tad, I get about 0.0015 now.

 

[redfishsc]

Had the same problem with a Delta. I bought it used, so I purchased a new spindle shaft (the part that the pulleys are mounted to that spins the headstock) and a new headstock bearing--- I did NOT replace the bearing by the handwheel, it seemed fine.

Everything ran great after that.

 

[Randy_]

While there is no doubt that it could happen, my experience is that bearings deteriorate over a period of time and don't just go bad overnight. If they are bad, you might be able to feel the problem. Loosen the belt and then turn the spindle by hand. If the bearings are bad, you may feel some roughness. Also grab the nose of the spindle and shake it back and forth and in and out. If you detect the slightest movement, the bearings are probably gone. There shouldn't be any movement.

While you are there, examine the belt very closely. If it has been around for a while it may be deteriorating and coming apart which could be another explanation for the vibration although I wouldn't think that would cause a pen to be turned out of round.

 

[Rifleman1776]

Things do wear out. But a well made lathe should last generations. I note you didn't say you cleaned the MT inside and out. Even a tiny speck can cause misalignment.

 

[Scott]

My first thought was the Morse Taper as well. A little bit of crud on the taper could throw you off like that. This is cheaper to fix than replacing bearings, too! Good Luck!

Scott.

 

[freedomhouse]

I have a knock off mini... had some vibe... check the screw / hex bolt that holds the motor onto the unit.... mine was very loose, it is now tight and most of the vibe is gone.

 

[Paul in OKC]

I would vote dirty taper as well. You can use some very fine paper to lightly buff the inside of the headstock. Bearings usually strat making noise or get real warm, at least in my experience, when going bad.

 

[wizical]

thanks for the advice, i have cleaned the headstock and tailstock, tighten everything done. I still dont understand it. im still working on it

 

[fernhills]

How about trying to loosen the brass knurl nut some.. it possible the mandrel could be skewed...

 

[Rmartin]

I had a problem with my Jet making a knocking noise. There are two hex head screws which can become loose. I removed the hand wheel, reinstalled, tightned the screws. It was like a brand new machine. Ran smooth and quite with little or no vibration.