Re: [CAD_CAM_EDM_DRO] Re: turret tool post for lathe

Hi Terry,

I like your description :-) I am aware that is how most lathes operate. The
reason I asked is because I am looking at a small CNC Boxford with a
vertical slide, which is effectively the same as having a rear toolpost
only. My gut reaction is that the chuck should turn the opposite way as the
slide is operating on the opposite side to a 'normal' lathe. Which direction
would be forwards in this case? The chuck is bolted directly to the spindle
with 3 bolts so it can't come undone if spun the wrong way.

Thanks,
Les

> Hi Les,
>
> The spindle direction is forwards when the chuck-key you left in the chuck
> hits you in the head. If the key bounces off your wedding tackle the

machine

> is in reverse. Tool mount in the rear tool post are upside down so that

the

> cutting forces are in the same direction as those mounted the the front

tool

> post. A parting tool will not then dig in and a boring tool will turn
> parallel to the lathe ways instead of turning trumpet, this is assuming

the

> lathe turns parallel when tooling is used in the front tool post. Unless

the

> lathe has a cam-lock chuck it should never be used to cut in the reverse
> direction anyway as the chuck will unscrew. In twenty years of machining,

I

> can count on one hand the number of times I've run a lathe in reverse.
>
> Regards,
>
> Terry
>