Another tool change question?

I see another similar question posted but I figured I would start a new thread for mine so I did not confuse things.

I want to add a tool changer to a column style mill.

Ideally I would like to call the tool number and have the Z axis retract to pre-determined position. I would then have a signal sent to classic ladder to initiate the removal of the existing tool. This would then the require tool changer to move into position under the spindle with the empty tool holder. Classic Ladder would then request the Z axis to move down to hand off the existing tool. After the hand off Classic Ladder would request the Z axis to retract so a new tool could be indexed into position. Classic Ladder would then request the Z axis to move down again to receive the new tool. Then back up again and the tool changer would retract and tool change complete signal given.

I don't see how I can make Classic Ladder cause a specific move in EMC? Is this possible? I think my entire concept relies on this being possible. I have seen other tool changers work in this way. I did not see any specific example of this type in EMC. I did see changers with the vertical component as part of the tool changer rather than using the Z axis.

Any help would be greatly appreciated.

Thanks,
Mike

Hi Mike

is this a rack type changer,?
or a carousel where the Z has to move up and down to unload the tool while carousel goes CW or CCW, instead of the carousel moving down & up?

i think the routers and like that you see that change tool moving the Z up & down and side to side are doing this in a sub program (you can call a sub G code program ether from a gcode file or from with in your program)
using any custom M functions in sub program to turn on or off any external hardware or turn a PLC bit on or off (unclamp tool etc...)

but im not 100% sure as i have not seen a full example of there setup files as when EMC sends out an M06 i believe all motion is put on feed hold until the tool change sequence is complete so doing the moves while in a tool change request state would require some changing of emc code i believe.

there are INI settings that let you send any axis to a predefined position in a tool change also.

hope this helps in some way.
rob

Hi rob,

Thanks for your thoughts. I have come to the same conclusion. The changer will be a carousel type on a linear slide. It basically has two axis of movement only. It looks like I can handle the original retraction of the Z by using the TOOL_CHANGE_POSITION = X Y Z statement in the EMCIO section of the .ini file. The rest will have to be done with a user G & M code program. I really would have liked to avoided doing it this way but I don't think I have an option for this concept.

Do you know of a way to compare against the selected tool number in G code? I could reenter it as a variable but I would like to keep it as simple as possible.

Thanks,
Mike

hi mike

EMC will not do a tool change if u are already at the tool it will skip the M06 (tool change request)

for a sub program gcode file u will have to pass a variable into the sub
and then process the position according to that value,
so for variable=1 go to pick tool from this pocket etc

take a look at the sub program examples in the manual

you wont relay 100% need to do a Txx M06 command as you can use a H with any tool, its just your display will not know which tool/tool shape is loaded in say axis back plot and a few other things. so its upto you how you deal with this part.
i dont believe there is a way to see which tool is currently loaded from a variable or not i could be wrong here though id do some reading and see.

i think commercial machines that have to move the Z to change tool they have a macro for the M06 which does all what you are trying to do in variables etc just EMC does not give you the pleasure of creating your own custom M06
rob