[S.Seveelavanan]

I understand integrating an ATC with linuxCNC/MACH3 is very do-able. But I have finding it hard to find any information on generating the tool paths???

What are the approaches to generating multiple tool paths for an Automatic Tool Changer (ATC)?

I guess a manual approach would be to create multiple design files: Say one wanted to use 2 tools, a large tool and a small tool, then one could create one design to first assign work to the large tool, then use the final design file for the smaller tool. Then the 2 designs could be given to the machine controller linuxCNC/MACH and executed automatically, including the tool change.

But... are there any intelligent CAM processors that would work out the above stage automatically? ... in terms of optimising the use of tools (e.g. to use a big tool do the heavy lifting first) Does Mastercam or any other popular CAM do this?

Any thoughts appreciated

Senthil

[aldepoalo]

The ATC just changes the tool. Instead of the operator having to switch out the tool himself the machine does it automagicly . The process you run on your parts, ie the order tools are called and machining strategies are left up to the user not the CAM program.

You just create tool paths for each tool in the order you want them to cut and when it comes to a tool change, the machine goes and grabs the tool for you.

This just makes it easier then having to make the tool change yourself.

The role of the CAM software for the most part is to write the g-code for the different tool paths you might create for any given part. A CAM system will offer you strategies for drilling, 2D , or 3D cutting. Most will simulate what you programmed and most important post the G-code to run on the machine.

[ger21]

Generally, the users makes the decision on which tools to use for which operations. Most CAM software isn't smart enough to know what you're thinking, or what you want to do.

If you need more than one tool for a job, the CAM software will add a toolchange command to the g-code so that Mach3 knows when to change tools.
The code is generally the same whether you are manually changing tools, or using an ATC.

[S.Seveelavanan]

Hi guys,

Thanks for the responses.

I think my understanding is correct in that an ATC will, when correctly set up, automatically change tools using G-Code in LinuxCNC/Mach3.

But I am still unsure about how intelligent popular software is in working with an ATC, with regard to the CAM/preprocessor/tool path generation:

Surely for high end $$$ CAM/'tool path generation software', you feed the software a 3d CAD file you wish to machine, and then it automatically works out the tool paths, given a certain machine and tool collection. Surely for these high end software packages, the software intelligently works out automatically which tool to use when, in order to optimise the speed of the machine or to limit the damage to smaller tools etc.

I was wondering if any such features were available for popular packages e.g. Mastercam etc, or how one could go about it without spending a million dollars.

A Manual method??:

@aldepoalo

You just create tool paths for each tool in the order you want them to cut and when it comes to a tool change, the machine goes and grabs the tool for you.

Say you wanted to use a big tool first and then a small tool:

Does this mean you tell the CAM/tool path generation software to machine your CAD file using a defined version of your large tool --> which generates gcode

...and then you repeat with a define version of your small tool --> which generates gcode

...and then you combine the gcodes, including adding the gcode for auto tool change, which you feed to LinuxCNC/Mach3?

is this how to do it?


Multiple tools with CAM software

@ger21

"Generally, the users makes the decision on which tools to use for which operations...If you need more than one tool for a job, the CAM software will add a toolchange command to the g-code so that Mach3 knows when to change tools."

Great. So there is a way to tell popular CAM packages to work with multiple tools.

If you need more than one tool for a job, the CAM software will add a toolchange command to the g-code

Does the CAM software work this out automatically? e.g. if there isn't enough clearance. Can you instruct the CAM software to use a large tool first then smaller tool?

Thanks again for the help

Senthil

[rowbare]

You tell the software what tool to use. No software I know of or could dream of affording will automagically decide which tool to used based on what is in the tool table. To have software try to do that would likely lead to a whole bunch of absurd compromises.

CAM isn't a magic box in which you feed a drawing and get a tool path out. You interact with the software to define the various passes i.e. roughing, finishing, waterline etc... Typically you choose what tool to use, the cutting strategy for that pass etc.. Then the software will generate the necessary tool paths. The better software will remember what material is left after each pass and will avoid air cutting on subsequent passes (rest machining).

I suggest you download a few demo packages and play with them. That will do more for you than anything.

bob

[aldepoalo]

This video should help you get started

[ame=http://www.youtube.com/watch?v=O8Es52fJ1js&list=PLFCF00E688197801B&index=9&feature=plpp_video]BobCAD-CAM V24 Getting Started 9 of 15 - YouTube[/ame]

[aldepoalo]

Here are some tutorials you can review as well. Most CAM systems will work in a similar work flow.

http://www.bobcad.com/wp-content/med...ine-part-2.pdf


http://www.bobcad.com/wp-content/med...chine-part.pdf

[aldepoalo]

Here is a video on feature based machining. Maybe this is the type of automation you are expecting.

[ame=http://www.youtube.com/watch?v=-tWf5bPLPFw]Feature Based Machining in Mastercam - YouTube[/ame]

[Al_The_Man]

Say you wanted to use a big tool first and then a small tool:

Does this mean you tell the CAM/tool path generation software to machine your CAD file using a defined version of your large tool --> which generates gcode

...and then you repeat with a define version of your small tool --> which generates gcode

...and then you combine the gcodes, including adding the gcode for auto tool change, which you feed to LinuxCNC/Mach3?

is this how to do it?
Senthil

To put the external process in perspective, There is no G code for tool change or any other external function.
G code relates to the motion control path.
All the the CNC controller does is run the Part Program and calculate the output for the required servo path, all other commands, M/S/T are unique to every particular machine, and are programmed by the MTB as to how they function, IOW all a CNC part program can do is declare a tool #, e.g. T2, this is passed over to the necessary software/hardware routine or physical PLC etc. to select the tool and declare the routine complete, whereupon the Part program continues.
IOW, a Part Program does not know, or care, how a M/S/T code is processed, it just needs to know when it is completed.
This also allows a Part Program to be transportable between different machines.
Al.

[jweinhold]

Senthil,

Understand a few items,

The Cam package only generates the drawings/geometry and the tool paths around them, your post processor generates the code. Most posts are supplied by the machine manufacturer and are specific to the needs of the machines control, tool changer(s), indicator pins, vacuum hoods and machine lay out. In most cases the post includes a VBA project to select tools, select work areas or zones and so on.

Use extreme caution with the simulation process, this is somewhat generic and may not truly show what the post processor will generate code wise. The best way to qualify your code is to read it.

Best regards,

Jeff

[S.Seveelavanan]

Thank you for all the replies.

I have downloaded some demos and am reading documentation.

Cheers