Need Help!- Reseting z to 0 in a program

[willheg]

Hi there everyone

just a quick question on something i have been thinking of for my mill i'm starting to build after a few years of ideas, buy bit's and peices and just mucking round with the idea.

anyway what i would like to know is if there is a way when you create a gcode program if when a tool change is done is there anyway to rehome the z to 0 by using something like a touch of plate and having it happen automaticly in the program after the tool is changed??

Any help would be great and thanks in advanve

Will

[jmelson]

Originally Posted by willheg Hi there everyone just a quick question on something i have been thinking of for my mill i'm starting to build after a few years of ideas, buy bit's and peices and just mucking round with the idea. anyway what i would like to know is if there is a way when you create a gcode program if when a tool change is done is there anyway to rehome the z to 0 by using something like a touch of plate and having it happen automaticly in the program after the tool is changed?? Any help would be great and thanks in advanve Will

Well, the best way is to preset all your tools, and use something like end mill holders so that the tools are always at repeatable length when installed. Then, you enter the offsets in the tool table.

But, there are touchoff plates that have been added to EMC2 so that automatic touchoff can be done. This may require you to use a development version of EMC. And, of course, if there is a chip on the touchoff plate or end of the end mill, you may not get an accurate setting. This was discussed on the EMC2 forums about 2 weeks ago, I think.

Jon

[willheg]

Hi Jon

Thanks for the information, with the way the machine will be setup i will only be using collets in a drill style/dremal sort of thing, so having the tool in a tool holder and using offsets is kinda outta the question.

This is why i thought of maybe a touch off plate and reset the z 0 point but now i'm stuck for what code i would need to use in the program to reset the z 0 point or how to instruct emc2 to do this and how to set it up.

Do you have a link to the related article on emc2??? if so could you post it.

Thanks again.
Will.

[jmelson]

Originally Posted by willheg Hi Jon This is why i thought of maybe a touch off plate and reset the z 0 point but now i'm stuck for what code i would need to use in the program to reset the z 0 point or how to instruct emc2 to do this and how to set it up. Do you have a link to the related article on emc2??? if so could you post it. Thanks again. Will.

The search feature in the linuxcnc.org forums has a problem so that you can only see
the first page of the search results. I will ask and see if anyone can find the thread or
where this feature is documented.

Jon

[jmelson]

Originally Posted by willheg Hi Jon Do you have a link to the related article on emc2??? if so could you post it. Thanks again. Will.

I think this is what you are looking for :
Calibrating tool length with a probe in EMC2 — jager.no

Jon

[chester88]

This is not automatic but could be, note it requires the tool to be grounded:

EMC Documentation Wiki: ClassicLadderExamples

just for more ideas

[willheg]

Hi guys.

Thanks for the help it's very good of you people.

i like the one jmelson has posted as it looks like i could just put this in my gcode file after every tool change and away i go.

the one that chester88 posted looks good to but confussed me to hell and back as i do not see how to put it in the gcode program after a tool chang is implimented, but still a good post.

Once again thanks guys and if i have anythingt else i'm sure i'll be back.

Will

[chester88]

for your use there is no need for the classicladder stuff. You could just use the plate instead of a probe or switch. by following the directions John linked for you.

[willheg]

cool that sounds good, thanks for the help will have to try it sometime

Will