hello
just bought this isel fb2 1000mm machine
want to convert to aplasma table
its 20 years old with round motors
do I want to change the motors to modern square nema 23;'s?
have done this before

- the z axis has an electro brake on it....
is it possible to use a braked z axis as a plasma axis?

do i fit the z axis from this little machine i have?
thanks

You can absolutely use that Z axis as a floating head for a plasma cutter, no brake function is needed.
However, do not underestimate the challenges involved in setting up THC wih Mach 3, especially when trying to do so with cheep USB controllers. There is an issue with the THC feedback process when using most USB controllers. As such, you may want to look at a standalone Torch Height Controller like the Proma THC150SD or a machine controller with built-in THC, like some offers from MASSO, though the latter can get rather pricey.

Speaking from very long, expensive and painful experience here.

Some old steppers lose their magnetism after a while. But some don't, check to see if they can overpower your pinch strength. If so, then they should be just fine for moving a plasma torch.