SETOYOTA, your machine sounds very cool. Beats my method of drawing the lettering out on manilla folders, then cutting with an Xacto knife!
I'm with Mogman on possibly overstressing the little grey cells, but I may have to look into one of these newer machines and see if old dogs
can learn new tricks.
As regards the old Marsh-style machines, they are big, heavy, limited to one font, one size, and take some experimentation to figure out how to best use them. But once you do, they produce adequate, and period correct, stencils.
They work purely manually. You clamp your card stock in where you want it, spin the wheel on top so the arrow lines up with the desired character, then pull the cut handle. The machine punches out the character and advances your card one space, so you select the next character with the wheel and repeat until you are done. Normally, you pull out your finished product, cuss a bit because you missed a letter, and do it again til it's right.
Cheers