Router - ? Zero, which way is + - newbee question

I am trying to find out where machine zero, zero, zero is on a gantry router. My assumptions are as follows:

If you are hovering in mid air over the table, looking down:

Looking down from the top

---

| |
| |
| |
| |
| |
|0,0,0 |

---

X Zero is this corner and
Y Zero is this corner (lower left hand corner of the diagram)

X positive is this direction --> (towards right of screemn)
^
Y positive is this direction | (towards top of screen)

Z Zero is up toward you
Z negative direction is down towards the table

To cut out a square, the Z axis would move in the negative direction (down towards the table), then the router could move in the Y positive direction (towards top or screen), then X axis would move positive towards the right of the screen, then Y axis negative towards the bottom of the screen, and then X axis negative towards left of screen (back to starting point) and Z axis up (positive direction to remove the cutter from the material).

Is this correct ?

Thanks,
Jim.

Searched the site but did not find anything - my google-fu may be weak.

That sounds like an appropriate coordinate system. That is how my router is set up.

You night want to look here...
wiki.linuxcnc.org/cgi-bin/wiki.pl?CoordinateSystems
gnipsel.com/linuxcnc/g-code/gen04.html
linuxcnc.org/docs/html/common/User_Conce...#_coordinate_systems

So yes your assumptions for a gantry router in the machine coordinate system (G53) are correct.
After your machine is homed you would normally jog to your work piece location and "touch off" setting say your G54 coordinate system.

Rick G