also thought so myself , but I saw what plasma is doing how it comes out . I thought it better to spend a little more and do  on the other side secend  axis

bad only because you can not do 1g-code for everything

I'm building a router with 2 Z axis.
I plan on using SwapAxis() during toolchanges, based on the tool number. Numbers under 100 will use one spindle, and numbers over 100 will use the other. I think you also need to use G52 for the second spindle offset. SHould be able to handle this in the M6 macros.

It can be done, but there possibly be a lot of macro programming involved, and as was mentioned, you'll be basically on your own.

MACH4 is suppose to have multi z axis support.

Just hafta wait, (;-) TP

I wrote to someone, he has Emc2 and controls the two axles

Sounds like you know what you need to do now. (;-)

(;-)TP

and there is a problem because I do not know this software

For 4 years there is no possibility, so you did not learn what's come on in this

Now it's 4 years, and another machine, and using who knows what computer , BOB, etc you are using.
Frankly, if you haven't solved the other three machines, or even addressed what was suggested in the other posts.....
you will end up at the same place only with a more complex situation to deal with. Then numerous posts and time will be spent trying to help
you and you won't do what was suggested.  Thus no closure on anything and the story will continue. Probably will go onto a 5th machine and start all over.

RICH

YNN,
  I think maybe you misunderstood.
"""I am building a cnc router with plasma ,on one Z axis  will be plasma on the second Z axis spindle."""

 "I Bad" for not understanding

Doesn't seen all that different than running a drill or impact marker on a separate Z axis.  If the second Z axis ends up being "A" then just use A instead of Z in CAM when you want to command that axis.

Another way is to put the secondary tool on a slide with an air cylinder and use an output to control the cylinder.  Air on and the tool moves down and below the plasma torch.  Air off and the tool moves up above the torch.  With the secondary tool in the down position, it becomes the active tool.  With the secondary tool in the up position, the torch would be the active tool. Either way, you're using normal Z commands on both.  You'd have to apply an offset to any code intended for the secondary tool, but that can be done in CAM.