How small can a plasma torch get?

For years Ive wanted a laser to cut parts for model engines, but to cut
metal I realize the laser power is too high and the prices way out of my
range.

But maybe a plasma cutter could do it- are there plasma torches that
will cut real small parts? Could I cut something like a model locomotive
frame, maybe 1" wide by 10" long, with a variety of cutouts?

Ive already built a CNC router for wood and plastic, and have a CNC mill
for oterh parts, but cutting sheet metal with a plasma CNC would be cool.

ron ginger