Sounds like you will have a fair bit of work ahead of you. My lathe uses Hydraulics for all of that but I think the actual mechanism of the two toolposts may be racks of some sort. Hope to get a better idea this weekend.
Hood

Well the Hardinge had options of vertical partoff slide and Parts catcher.   Both not fitted to this machine, but I will add a parts catcher.

The partoff slide was hydraulic but driven by an air motor powered pump.

I'd expect your machine has hydraulic chuck, and maybe turret locking.   Usually the racks are air driven.   You will soon tell if you find any 5 port valves on the machine.   Just hope they don't all leak like mine did!   They are expensive....

Wayne...

Wayne
No air at all to this machine, just hydraulics.
Hood

Well you know what I said about the cutting oil preserving the machine    Well thats true regarding the iron, but not so good for the cables!

The pic below is the turret encoder, as you can see the once flexible cable (BICC Brand Rex so not cheap stuff) can now defy gravity HEHE....

Needless st say I can't leave it like that, so all the affected cables will be replaced, as I can't afford them cracking up later when the machine is back together.

Also for those interested I found an old vid I did of the turret and tailstock working. This was the day I spent working out the logic of the turret sequencing.   You can also hear the air leaking from all the 5 port valves.  and the compressor comes on part way though for a top up!.

Link is here http://homepage.ntlworld.com/fdosdesign/temp/hxl_turret2.mpg

The turret should NOT do the little clockwise rotation on the way back down, thats now fixed.  The Air cushion that the turret indexes against needed adjusting.

Wayne....

Wayne
 got any more of these encoders, I think you could make a fortune by selling them as modern art
 Indexing looks good, I got a bit of a fright when the tailstock shot out, for a second I thought I was going to hear a crash 

Hood

LOL....  Well I'm just glad the encoder works.  They cost a fortune from hardinge. I tested it last night, and one of 4 hall sensors outputs goes low for each station.

Today I very carefully used a die grinder and carbide burr to dig out the epoxy potting from around the cable entry, the old cable is now gone and I have enough of the tails to solder a new one to.   Then I can repot that section.

Wayne...

Got the CNC Teknix TEK10 drive quickly setup a little while ago.

Test Power supply @ 45V not quite enough to give me full speed or full current probably.

Setup with divide by 8 to give me reasonable speed with this high count encoder (2500count or 10,000 per turn of ballscrew).

Tuning no where near where it needs to be, but effective.  I'll need to make a lead to connect to the scope.

But so far so good!

Quick video you can downloaded from here. http://homepage.ntlworld.com/fdosdesign/temp/tek10_test.wmv

Looking good Wayne

It's a good start.

Got to order a big 45v transformer to give me close to the 65v the motors are rated to, then we can really see what happens!

Tuning the drives will improve things too, I was never able to run the old motors with these encoders at anything above 25v on Gecko 340's.   But the old motors were pretty weird and shagged out..   I've just been tweaking the PID terms and got it to be quite snappy, but think the current on the psu is not anywhere near enough. 35v 150VA.  which is 4.28A only 280mA above the continous rating of these motors!  I have a 1kvA transformer in the stores somewhere, I may try that tomorrow.

Wayne...

Got the billet for the Z Axis motor mounting plate yesterday so spent part of today machining the replacement with a larger offset to get the pulleys alligned correctly.

You can see I have stuck with the original design mainly, except the recess for the motor is now round to suit the new motors.   I shall also be getting a sheetmetal working friend to make me up some splash guards to protect the motors from the flood of cutting oil in the machine.  These will bolt to these plates.

Hopefully tomorrow I can try the Z axis with the Teknix drive, and see how well it performs with room to accelerate over that longer distance;)