Milling Machine Multiple Heads

umbaman wrote:

Each tool is activated by a pneumatic cylinder. When a tool is needed the coresponding cylinder is activated and the tool descends a predefined distance.
How can I configure LinuxCNC so as when one tool is at the limit of its workspace the next one continues?

Do you ever want to use more than one spindle at the same time? (For example to make duplicate parts.)

This sounds quite a lot like a tool-change. The tool-able allows offsets in al directions, so if you set up tool 3 to have a 700mm X offset and tool 1 to have a 0 X-offset, if you do a tool-change to tool3 then the working point will automatically offset by 700mm.

In your position I would be tempted to set up 15 "tools" where each number is a binary representation of which tools are up and which down. That makes controlling the cylinders from HAL somewhat easier.

umbaman wrote:

So do you suggest setting up the tool-table and in the CAM s/w predetermine the area each tool will cover?

Yes, I think that is the only way. LinuxCNC won't even let you run code that is outside the area that it thinks the machine can reach. I don't know of any way round this because it would be extremely hard to coordinate the spindle-swap with the G-code. This is partly because G-code is a rather simple and old standard, and there really isn't any information flow back from the machine to the interpreter. You are asking the machine controller to (potentially) split a long G-code move into several shorter moves and that just isn't possible with the way that the software works.
Not that it is completely impossible, but you would need to re-write some pretty fundamental bits of the software to enable it. (I very much doubt that any machine controller can do this, I think it would always be done at the G-code level, manually or with CAM)

In your position I would be tempted to set up 15 "tools" where each number is a binary representation of which tools are up and which down. That makes controlling the cylinders from HAL somewhat easier.

I don't quite get this.[/quote]

Tool1 = 0001 = right-most tool.
Tool2 = 0010 = next tool to the left
Tool4 = 0100 = second from the left
Tool8 = 1000 = right-most tool

Tool9 = 1001 = both outer tools

Tool3 = 0011 = both right tools

Tool15= 1111 = all tools down.

This may be less obvious if you don't count in binary.

umbaman wrote:

In Asprire 3.0 it says that the postprocessor (emc2) does not support toolchange when I selected multiple toolpaths to be included in one file.

I am afraid that is an Aspire problem, not a LinuxCNC problem. LinuxCNC definitely does support tool changing.