Hi Bradford
If you have an adapter to fit another lathe, it would not be in your
chuck when on the first lathe, wouldn't fit right.
You would keep the adapter on your other lathe so you can use the same
chuck on both lathes even so one lathe has a different thread size
from the other.
There is a problem with the set screw, in that it was made to fit on
the Oneway lathes, some of the other lathes also have the flat area
machined into their spindle but not at exactly the same distance from
the shoulder the chuck seats against, and some lathes just don't have
the flat area.
Most people do not need to have the chuck locked to the lathe, but for
the very large lathes that have the breaking resistor to quickly slow
down the lathe the large bowl blank could spin the chuck off the
spindle, when the lathe is stopped, or if the lathe is reverse turned
on.
Have fun and take care
Leo Van Der Loo



On Mar 4, 9:28 pm, Bradford Chaucer wrote:
It is used whebn you use an adapter with the chuck to fit it to other
lathes to prevent the adapter from unscrewing from the chuck body when you
remove the chuck from the lathe.

On Sun, 04 Mar 2007 19:44:02 GMT, "Bob Daun" wrote:
I have used my chuck for quite awhile but I was just wondering why there is
a threaded hole in the back end of the adaptor (the side facing the
headstock when mounted). The threads in the hole are quite fine but there
is nothing in the hole. If I shine a flashlight into the hole I can see the
threads from my headstock. Is this meant to use as and additional hold
down? I would hesitate to do that as it would ruin the headstock threads.
Any thoughts on this?