Re: Air assisted ball/screw on Z axis(table hei ght) ?

Cool!!! Thanks Tim, glad you knew that. It make too much sense now
that you say it. I just hadnt figure on investing in shop air yet.
Gonna have to redo my budget. :)

By the way hope this is good news, the mill is 99" fully
upright. My 103" figure was including the 4x4 it was
sitting on in the rigging yard. Just cleared the ceiling
by 1.5".

Thanks,
Lee

--- In CAD_CAM_EDM_DRO@egroups.com, Tim Goldstein <timg@k...> wrote:
> Lee,
>
> To counteract the weight of the table the machine has a pneumatic
cylinder
> that holds most of the weight of the table. The motor than carries
the
> balance of the load and has to work against the mass but not the
weight
> (think of it like moving a object in space, it is weightless, but
still has
> mass that resists movement.). So, If you turn off the motor and
shut
down
> the air the table will start to drop as the resistance of the
ballscrew
> friction and the non-energized motor is not enough to hold the
table up.
>
> Tim
> [Denver, CO]
>
> > The mills that Tim & I got have a plate on the Z axis drive
> > motor that says:
> >
> > "This Machine has an air-assisted Z axis ball screw. The knee
> > clamps must
> > be tightened if the air pressure is removed and the console
> > turned off.
> > Otherwise the knee will lower itself to its bottom-most position."
> >
> >
> > Could anyone shed more light on this and the concept of air
> > assisted ball
> > screws.
> >
> > Thanks, Lee