[PeterJK]

Howdy! I am a first time cnc router builder, and need some input from seasoned cnc'ers. I haver searched online, but I find conflicting answers.

So - Which do I set up as the X axis, and which one Y ? I will have 0, 0 set at the lower left corner of the table, so it seems logical to me that Y will be the long axis - the length of the table, and the X axis will be along the gantry. Your thoughts please.
Thanks!

[tijundonghua60]

Great. There's nothing left to edit. drift f1 Just keep doing it

[routalot]

Entirely your decision and all you have to do now is create your CAD files to suit the arrangement.

[D_moll]

As mentioned it's up to you!
There is nothing wrong with placing the machine in any quadrant, if it suits your needs. (1st. +x, +y... 2nd. -x, +y... 3rd. -x, -y... 4th. +x, -y)
However.... (there is always "however" )
While working with multiple CNC machines it could be confusing "switching" between systems.
Most machines are in first quadrant (at least that I had a chance to work with), and that is what I find easiest, as it's a landscape design with zero at bottom left and all positive axes. (as shown in your first image). Also the machine is parked at 0,0

[PeterJK]

Thanks for the advice. 1st quadrant it will be then!

[awerby]

Usually X is the longest axis. It works out better for laying things out on a monitor screen, which is wider than it is high. Most CAD programs will present you with a screen for the basic plan view that has Y going vertical and X horizontal. But it doesn't really matter much, as long as you can remember what's what.

[CNCMAN172]

The traditional CAM approach is X moves left to right with left being zero. Y moves front to back with Front being zero. This is your typical XY plot from school. You can make it work other ways as well as long as you setup your CAM and CAD programs to use the same coordinates.