Re: Sanity check on home switches

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "washcomp" <jeff@w...> wrote:

> I am of the assumption that the home (zero) of the X axis should be
> the left hand limit switch (table all the way to the right), the

home

> of the Y axis should be the rear limit switch (table all the way
> towards the column of the mill), and the home of the Z axis should

be

> when the spindle is all the way up.
>

Jeff, I think you have it backwards, assuming a comercial machine in
the US. On a moving table machine like a mill, the table is to zero
at the right rear of the table. This means that when you home, the
table moves forward, away from the column, and then to the left in
X. In this manner all your work/fixture offsets will be subtracted
from the machine coordinates.

A fixed table CNC router will move the gantry carrying the spindle,
to the front left position over the corner of the table.

Fred Smith - IMService
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