I have an old Delta 46-700 lathe I got a few months back. It has a 3 jaw chuck in it but it does not go small enough to accomodate my cork mandrel. Do I need to buy a Jacobs chuck or something else to go into the 3 jaws so I can hold smaller diameter pieces? New to wood turning so any help you can provide would be great.

Matt White

You might just want to go to penn state industries website. PSI has many good priced chucks and adapters. I assume you have a #2 morse taper and and 1 x 8 tpi headstock. If so check out PSI. The jacobs chuck would have a taper to fit into the headstock. You might also consider a collet chuck system which will hold the mandrels very securely. I have both. In my experience the three jaw chucks do not hold mandrels well. You also need a 60 degree live center for the tailstock.

In a pinch, you can build up the end of your mandrels with tape or fashion a rigid bushing to serve the same purpose.

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I actually tore the chuck apart and cleaned it well. It now will clamp just barely enough to hold the madrel still. I have a live center on the tail stock already as well. I do not know though if the head stock is slightly wobbling or the mandrel is wobbling but something is moving a bit. It works good enough to sand down cork but I don't think I'd want to do wood the way it is now. I made a cork fly grip today on it and it worked out pretty good but definately some things to work on!

Matt White

Be VERY careful if you have ANY wobble, it could be dangerous. You might want to read this thread [rodbuilding.org] You might want to slide your mandrel through the chuck until only what you need is exposed and put a dril stop collar on your madrel at the chuck to prevent any slippage!!

Mike (Southgate, MI)
If I don't want to, I don't have to and nobody can make me (except my wife) cuz I'm RETIRED!!

It's possible that your mandrel isn't straight/true.

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How old id old? If it had a lot of use, or heavy use the bushing or bearing in the head stock could be worn. That would cause wobble. Does it wobble all the time or only when under pressure? If it wobbles only under pressure, suspect worn bushings/bearing. If it wobbles all the time, then roll the mandrel on a known flat surface to see if it is straight. If the mandrel is ok then the bushings/bearings are badly worn.