ATC for MPCNC using Hirth Couple Z axis center distance

Hi Ryan,
I’ve been getting a itch to build a tool mount for the MPCNC using Hirth Joint.
You did an insane amount of optimization on the primo-core and I’m not even sure if this going to work with how packed in things are to minimize the overhang on the router. For my project, I’m looking to swap between a pin cutter, pen plotter and a vinyl cutter for the Primo we have at the makerspace that I’m a member.
To start I want to manually swap the tool by dropping the zaxis and unscrew a single bolt that holds the hurth joint together to disconnect the tool. If this works manually, I’ll figure out how to automate automated, (although manually unscrewing a single bolt might be good enough…)

I know you only release Stls(which is fine) Can you tell me what the z-rail center distance is for standard US Conduit? I tried reverse engineering the Z-motor-c-primo mount and I’m going up with a CD distance of 69.356mm? I’m not sure that’s correct since it’s not a nice number? (How close am I?)
By chance do you happen to have a stl that you are are willing to share of the Primo Core with everything assembled less conduit? I want to 3d model an assembly of the mount/pipes in Ondsel/Freecad and check it to make sure I don’t smack into anything virtually against the primo core sub assembly.

I suppose I could do this manually with the Stl’s but I was hoping to avoid that.

In my googling, researching this, I haven’t really found any hits for what I’m trying to do with the hirth, which actually surprised me.

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Could you use the blank tool holders that @vicious1 has released as the basis for your system?

The blank tool mount should give you what you need. Not really sure what you are trying to accomplish with that sort of system?

I actually do not have access to Solidworks right now to check those dimensions.

Yes… I think that blank tool holder should work… It give me a boundary to work with.

The hirth coupling as a tool holder is just an itch I’ve had that’s been needing to be scratched…
I plan to 3d print it.

Here’s a fun video of machining one… At the very end they show it being used on a cam…