New here - and need your help

[KnoxPhil]

Hello, All:

First, thanks to all the active posters who have allowed me to learn so much during my last few months of lurking here. You folks are quite a knowledgeable group.

Second, I'm hoping some of that knowledge and experience might help with a situation that has developed, well, today.

I have a Jet Mini and a Supernova 2 chuck that have been serving me quite well for the 6 months I've been turning. However, I go out to the garage today to do some mini-birdhouses; it's been weeks since I last turned - my garage gets awfully hot.

Strangely, there is suddenly a lot of 'wobble' present in my chuck, and I don't mean just the jaws. The entire chuck is rotating noticeably off. Broke the spindle assembly down, lubed (since I ahd everything out), and reassembled. The lathe seems to spin quite well, that is, until I put the chuck back on, then it wobbles again. The severity of the wobble is such that I can't turn anything smoothly using the chuck.

So, let me pick your collective brains. Anyone experienced this before? Any suggestions as to the cause? Even better, any suggestions as to the solution?

Thanks in advance for your help, and I look forward to future interaction.

Phillip
Knoxville, TN

 

[C Edward Moore]

Chuck wobble

Phillip,

Let's examine where wobble can occur:
1. Spindle problems;
2. Chuck problems;
3. Where chuck meets spindle.

From your comments, the first place I would look is #3. I would check to see if the adaptor is seated firmly in the chuck and would probably retighten those screws.

Then, is the chuck seating against the spindle face as it should? If not, why not? Does this chuck have a screw to prevent the chuck from loosening while the lathe stops? If so, maybe this is preventing the chuck from seating properly.

You seemed to think that the spindle was fine. Is the handwheel tight? Sometimes the position of the handwheel determines the play in the spindle, or prevents same.

Good luck.

 

[arbud]

Nova problems

If all else fails then you should contact Tim Geist, T.V. Geist Mfg., 304.295.8166. He's the the repaiir station for Nova products in the U.S.
He's helped me in the past.

 

[KnoxPhil]

Thank you both for your input. I have given everything a semi-thorough check using the points set forth by Ed; a complete inspection will have to wait until after work today.

Will provide a complete report.

Thanks again!

 

[C Edward Moore]

Hmmmm!

Phil,

BASIC PRINCIPLE: Work the problem from the spindle-head towards the tailstock.
1. Did the wobble occur before the spindle breakdown and re-assembly?

If not, then the problem is in the spindle area. Maybe the play in the spindle needs to be reduced. Try putting a blank (2 x2 x6, or larger) between centers and see what happens. Turn a tenon to fit the chuck on each end of the blank - smoothing the tenon and squaring the shoulder. If there was no problem, then remove the blank and put the chuck on the lathe and snug it up. With the lathe turned off, push, pull, shake, rattle and roll and see if you can find where the wobble is occurring.

2. If the mystery continues, remove the adaptor, clean it thoroughly, and very carefully clean out where the adaptor seats. Re-seat the adaptor and tighten, using an approach like you would use when putting a wheel on a car so as to have equal torque on each lug.

3. If no answer yet, inspect the spindle-head and where the adaptor would square up against it. These surfaces must be clean and without a burr.

4. Put the chuck on the lathe. Move the tool rest up close to the body of the chuck, but not touching it and not where a jaw could hit it. BY HAND, rotate the spindle and put your thumb on the toolrest and against the body so as to sense any change as the chuck rotates. If you have a dial indicator or have acces to one, then you might use it here. If there is no problem, then put the blank with tenons in the chuck very carefully. Use your tailstock to ensure that the blank is centered. Once tightened and the tailstock is backed off, turn the spindle by hand and with thumb on the toolrest near the exposed tenon, see if wobble is detectable. If not, then move the toolrest and turn on the lathe.

5. If wobble persists, either call the tech rep as was suggested, or ask a machine-knowledgeable friend to come over and go through a check with you.

6. And if the wobble is still there, I suggest religious counselling. 🙂 I do not know whether excorcism for lathes is appropriate or not.