Hardinge Chucker Spindle Question

[spumco]

I hope this makes sense. I have a chucker headstock with a 5C collet taper and threaded nose.

I want to have the option of bar feeding on this. This means an air collet on the back of the headstock (Dunham Tool) or something similar up on the nose.

A third option is to put a cylinder on the lever arm. I'm open to any and all options really, but the point is that I want this to happen automatically.

As I'm looking around the interwebs, I'm realizing I don't really think there is a good option for a nose mounted air collet for the style of spindle nose I have. As I continue looking, I realize I don't know what the industry standard name is for my spindle type. I see A5, A6, D1, D2, etc. (I'm sure I'm getting all of that wrong) but I don't know if mine is one of those or something else. I suspect something else, so I feel like I'm wasting time for something I'm unfamiliar with.

Hardinge experts, the question I have is: does the design allow for an air collet closer on the spindle nose with the style of spindle I have? If so, how is the spindle nose locked and clocked with the collet closer for reverse rotation? Or is the clamping pressure enough to do that? And if I'm correct in all of that, what do you call this spindle type?

I suggest going with a rear-mounted pneumatic drawbar. The nose-mounted ones (Rovi sells one) overhang quite a bit and are fairly large diameter. If you're going for a fast little gang-tool lathe you might run in to problems with tool clearance with a large dia front cylinder. Plus you (potentially) give up the concentricity of the spindle ID taper.

Hardinge made a couple different ones, and Dunham also makes one. And the air-cylinder connected-to-the-lever setup is also viable.

Since you're going for an all-auto config, you can pitch the front on/off switch & wires and use those mounting holes (they're decently beefy) for an air cylinder bracket.

Another nice feature of a rear-mount cyilnder is that you can use a true dead-length collet stop for 2nd op work. Dunham makes one that mounts to the air cylinder and is fixed in relation to the spindle (doesn't move with the collet). No need to buy the expensive Hardinge dead-length collet system, and the Dunhams are externally adjustable for faster setups.