intro and a few questions

["dennis pantazis" <dennis-at-pantazis.org>]

greetings all:

i have recently joined this list and have been scanning the archives to
glean info. i am planning my jump into cnc with a bdi. i am an
semi-experienced linux user and have had the fortune to use high end
machines (puma lathe, hurco mill, ...) i have the basic gcode knowledge. as
far as linux goes, i am able to patch, compile and install source packages.
i do ok at basic scripting. surprisingly, my concerns are not about getting
the emc/linux combination to work, its the other stuff.

i have been scouring the archives of the yahoo cad/cam/dro list as well, but
so far i have not had any luck figuring out the last bits. if anyone can
help me get over this last hurdle, i would appreciate the guidance.

my first project is to build a gantry type table to use with either a
cutting torch or a plasma cutter. i have most of the mechanical tidbits
figured out, and i am hoping for an overall size of about 4'x4'. 2d for
sure, maybe 3d to adjust torch height, and i am thinking that i want a
coolant off/on type function to control cutting function on/off. its not
unlike the cnc router type affairs that i have seen, only for metal.

1. is the torch on-off really another axis? can anyone suggest an means of
control.  it would be a simple off/on solenoid type control.

2. the only other thing at this point that is holding me back is the motors.
stepper or servo or chopper type. i tried a couple of the links to the
stepper motor tutorials, but they seem to be dead.
can someone point me to a resource or faq for them?

3. lastly, the whole notion of torque ratings of the motors. again, pointers
would be great. i don't think i need gorilla torque or speed..  i am looking
for 10-80 inches per minute travel. i have been scouring the scrapyard for
motors, and surprisingly enough, i see A LOT of them, but havn't been able
to identify my needs.

again, i know this is mostly a dedicated emc list, but i am hoping someone
can point me in the right direction to get over these last remaining hurdles
to get going.

thanks in advance

dennis