Wiring A Relay For Master5

I would like to have a relay send 24vdc to a pull type soleniode
mounted to my plasma torch handle. (I don't want to modify my torch)

I have built an x y gantry, and a control box with a pair of gecko
201's.

Is there an easy way to accomplish this? Can I use a pin from the
parallel port connected to the relay coil? I see in the schematic
for master5 the use of an uln2004 IC and 12vdc relay. I have the
5vdc from the computer power supply zip-tied to my parallel cable and
a 24vdc power supply for my motors which I plan to use for the
selenoid. Do I need to add the 12vdc for relay and chip or can I use
a 5 volt relay and the power that I took from the computer?

Thanks for the GREAT list... This is so cool that a hobbyist can
build a computer controled machine.

Kevin Campton
Scottsdale, AZ