CNC interface PCB

Hi All -

I'm working on a custom interface board for my controller, and I
have some questions regarding power capacity of PCB traces. I
would like to use an isolated corner of the PCB for some relays
for energizing external devices (coolant pump, air cylinders,
etc.) as well as possibly cutting power to the Gecko's under
estop. The worst case is the Gecko's, rated for 80VDC and 20A.
Obviously the Gecko's are supposed to handle this on a PCB, and
I'm wondering what it would take in terms of trace geometry to
handle the same ratings going from screw terminals to relays and
back on my PCB. Has anyone fried the traces on their Gecko's?

Another issues is actually finding relays that can handle 80VDC
and 20A (no, I don't plan on actually using this much power out of
the Gecko's...). What components are others using for estop
relays? Are you cutting power to each drive individually, or just
cutting off the power supply?

TIA,

Carlos Guillermo
VERVE Engineering & Design

PS-
Do the Gecko's use a 4-layer board??? How much difference would
this make in terms of current capability of the traces?