Thanks Guys.
I have been going back and forth on the open loop vs closed loop vfds. some say that a closed loop vfd will keep perfect time and then mach only needs the 1 pulse per revolution.


The existing motor is the original 1.5hp so would be looking to switch up to a 3hp, its the vector vfds that jump up in price.

I'll have a look at the cards. as I want to do fine threads. I have just got two pci card encoder controllers but they are absolute and not incremental so probably no good. any motion controllers you can recommend?

Thanks for all the Links Rcnc, I will have a look later.