I am looking at a machine with a delta 20 on it that has troubles and have been looking very hard at a conversion if I do buy the machine. It's a Lagunmatic 250, the servo motors work. I am just kinda lost on the hardware to buy. I have looked at the mesa and pico hardware, and dug through a bunch of builds. With all the variations I am trying to narrow it down and get a better idea what I may be getting myself into.
I know nothing of that machine or control, but you need to figure out what kind of input the servo drives need, and how much I/O you want to integrate.
then you can pick your hardware.
if the drives take step/dir input and can handle the encoders themselves, then you may get away with just a parallel port, if you can set the electronic gearing so you can output pulses fast enough. resolution will be low though.
if the drives take analog input, or don't directly view the encoder signals then you will need a card to interface that with linuxcnc.
post what kind of drive hardware it has, and the manuals will give a better idea of what you need.
I have not pulled the trigger on it yet, I have had conflicting information on if it has linear scales or encoders. I should know soon, I'm going to call the guy that has the machine in a bit and see if he will bite on my offer.