Hi David, We got a chinese machine to cut phenolic duct, the machine has two heads (routers), we want to use one head for grooving and the other for cutting, I am able to make the g code in Camduct and when I use mach3 to operate the machine it works the both heads at the same time. 

I set the post number: 1 for the cutting router and post number 2 for the grooving router.

Where is my mistake?

Thanks for your help.