Re: Air/hydraulic Power Chuck

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Tim" <sspeed@o...> wrote:

>
> Interested in fitting some sort of automatic chuck to
> a 12X36 Grizzly lathe.

If you're speaking of a jaw type chuck, the chuck itself is just part
of the equation. You also have to have an actuator, either air or
hydraulic, and either can be solid or hollow depending on whether you
need to maintain a hole thru the spindle or not, and on the design of
the chuck. Then you need a drawtube or rod as Kim mentioned, made to
mate with the chuck and the actuator. If the system is hydraulic, you
also have to have a hydraulic power supply and associated valving for
control of the chuck opening and closing. Obviously the air actuated
chucks don't need a hydraulic system, but they still require the
valving and in both instances you have to have a rotary union to feed
the air or oil from the stationary piping to the rotating spindle.

I hate to sound discouraging, but the reality of adding something like
this to an engine lathe is neither cheap nor simple. To further
complicate matters, most all the power chucks you'll find are made to
fit an A type spindle, whereas an A spindle nose on a small engine
lathe is a rare thing. Most chucks are for use with hydraulic
actuators, and would require a relatively large actuator if air was to
be used. There is such an animal as a front mounted air actuated
chuck which combines the chuck and actuator in one unit. A ten inch
one will push $9000, and they're rare as hen's teeth in the used
market. I know, because I've watched for one for several years.

For a lathe such as this I'd look at either a lever actuated collet
closer, which pops open and closed with the movement of a lever, or
one of the front mounted jacobs type collet chucks which uses a
handwheel for actuation. With a lever type closer you can use 5C step
chucks to work on larger diameter stuff, up to about 5.5" or so, and
use the full range of normal 5C collets for thru hole bar work.