Considering a Full Rewire on a Working Schaublin 125 CNC

I’m heavily dyslexic, so I write it myself but let ChatGPT make it readable, even though it changes the grammar more than I’d like — it’s still better.

Regarding the question of manual tool changes, what I mean is this:

Consider that you have a toolholder with two tools in tool-changer position 1. Because you’re making a very complicated part, you need more toolholders than you have positions in the changer. In this situation, you will eventually have to exchange the holders manually.

What I want is for the machine to ask me only when my input is actually needed. I’m not too concerned about a few unnecessary moves.

What I do want to minimise is the number of times I have to intervene, and the number of points where I can mess up. That’s why I want a single point of truth for the pocket number on a ganged toolholder.

Edit:
Examples of when it should not do a manual tool change:
Changing to a different pocket that already has the correct toolholder in it.
Changing to the same toolholder but to a different tool mounted on that holder.

And if it does need me to exchange a holder, it should have already rotated the turret so the pocket to be used is positioned in front

The sort of thing you are imagining is a bit of a fantasy for our kind of lathe and use case. A perfectly synced tool table in CAM and LinuxCNC is unlikely to work, as you will never have enough tool holders to never have to edit them. Think drills. I can say from experience that the next size drill you need is never the one loaded.

Maybe on those big machining centers with chain type 60 tool magazines, but it is not going to happen on our set ups. 

In practice, there are two scenarios.
- You are making one off home shop/ tool shop parts. You have enough tool holders for  the most common tools, and you have assigned them pockets where they are most often used. For these jobs, you will often not program full multi tool programs, but use a mix of simple programs for more complex bits using a single tool and Lathe macros for simpler paths where you also manually swap in tools. 
- You tool up the machine for a production run. In this case you will go through and set up each tool, assign a pocket and if needed set manual break points for manual tool changes with our lathe. Tool set up is a fact of life in CNC machining. LinuxCNC can't know which tool holder you are planning to swap in manually.

There are many many more things to work through getting your lathe running under LinuxCNC before you even need to consider this issue.

 

You are absolutely right about most of that, and it’s certainly many months in the future.
But one nitpick: what I want is not a perfectly synced machine/CAM system. It’s more a system where we don’t have to care about the sync. But let’s leave that aside for now. I can revisit it in due time and see whether it works the way I think it will or not.

Martin