Re: Asian Lathe Conversion

Thanks Roger:

Yes, I have been wondering what would make a good Screw Thread
protector.
If there is enough room between the screw mounts and the ball-screw
mount when the carriage is at either of it's extreme travel points, I
can picture some sort of telescoping tubing arrangement, or some sort
of flexible bellows (?) type tubing. Does that make any sense?
I would prefer a totally enclosed shield if possible, rather than
just a metal cover. I'd like this for my Mill too. Even though the
screws are tucked under, I'll find chips when cleaning.

You mentioned that PC programs don't handle threading.
I think someone on this list recently referred to some program for
doing threads. I know that the spindle needs to be synchronized with
the lead screw in some manner. This should be simple enough by using
a low resolution/high speed encoder on the spindle. Or small magnets
and a Hall Sensor.
I don't know much about commercial applications for CNC.
I have a bad habit of writing my own as needed.

Tom M.

> "vrsculptor wrote:

> Tom,
> I was considering this problem for my own conversion. If you add a
> second lead screw out the back with a low pitch ballscrew (I think
> less than or equal to 5 tpi) it will free wheel when not in use.

You

> may need a belt disengage lever to disconnect the axis motor. You
> need a way to protect the ballscrew from chips. The cross slide
> could be handled by replacing the handle with a handle/pully
> arrangement so it would work both manual and automatic.
>
> Bummer for me is that PC cnc programs (EMC or my favorite Mach1)
> don't handle threading. This shouldn't be a problem for you.
>
> Roger