....
I'll look at them in more detail in the next day or two. I see that your
ATC is not the basic carousel style used on the somewhat smaller
machines. Looks like you'll be needing at least four outputs and about
eight inputs to control it, and a bit more scripting for the tool change
routine. Nothing overly complicated, just a bit more than the basic
carousel type. On that relief valve I believe that the hex nut seen just
past the black knob is the lock nut which prevents the setting from
changing due to vibration. You'll likely need to back that off a good
half to one turn before the knob will turn.

Existing ATC has WAY more I/O than that. About 18 outs and 24 - 30
ins. I could reduce ins considerably with two encoders. But, that's
next year's problem.

I'll try again on that relief valve. With two combination wrenches, I
couldn't get these to separate. The whole vave end will easily screw
out though. You can't see from the pic but that 8x8 hole in front of
the relief valve opens up to a cavern that is the whole inside of the
machine and coolant sump. That's where the spring and ball would go
if I take it apart.

Karl