Centroid Community CNC Support Forum

I don’t want to home the Z axis, just the X and Y – I plan a plasma unit. I looked through the documentation and searched the forum, but I can’t seem to find an answer. Maybe I just missed it but is there a way to do that?

Tim

Don't designate a homing sensor or switch. You will need to make sure the Z is near the top of it's travel before you home the machine, or edit out the M26/Z line in the cnchome file

Help me understand what you're saying.

Right now I don't have a Z homing switch. I am going to use ohmic touch-off for the Z position. It's my understanding the homing routine always starts with the expectation that the Z axis will travel to the homing switch. How do I "tell" it not to try to home Z? Yes, I could modify the file and eliminate the Z home command if there is no other way but I thought that since it was designed to support plasma machines there would be a way to easily eliminate that step.

Yes, making sure the Z is clear before moving in X or Y is understood.

If you do not define a Z switch in the input configuration AND you do have a Z axis defined, the controller will not "home" the axis, it will simply set the machine Z home at its current position. You will use the ohmic sensor to set the part (WCS) Z zero.

That said, and if you are using a retract height in your files, if the machine Z zero is not high enough you may have a conflict with the travel limits (if set)

Thanks for the info Gary but I’m still confused.

As far as I can see in defining inputs with the Wizard there is only one selection and that’s “Home All” and that’s defined to IN1 which is where I have my NC parallel switches wired. To be clear, I have a slave home switch (the X axis is slaved) wired to IN2 and selected. I also have a torch float switch wired to IN3 as a backup to the ohmic touch off. The input type is defined as Plasma.

That said, how do I not define the Z switch?

I'm attaching a cell phone image of the input page that may help.

In looking at your video page I see you use an acorn controller to control your ShopBot. Nice to know if my current ShopBot controller ever quits.

Again, thanks for the help.

Tim

You can either use HomeAll and remove the the M91/92 /Z references in the cncm.hom file to inhibit the axis search for the home switch. The M26/Z will set the home position at the current Z location.

Or instead of using HomeAll, you can use two inputs for X home and Y home.

The only options I have for defining the inputs are those listed on the Input Type options shown to the left.

Tim

Click on input type and select "All"

tblough wrote: ↑Mon Sep 12, 2022 1:42 pm You can either use HomeAll and remove the the M91/92 /Z references in the cncm.hom file to inhibit the axis search for the home switch. The M26/Z will set the home position at the current Z location.

Or instead of using HomeAll, you can use two inputs for X home and Y home.

all,

fyi...if you choose to use individual homing inputs for X and Y you'll have to edit the autosquare macros to accommodate that change. the autosquare macros we provide support the configuration shown in the axis pairing manual. this is the 'stock' way to do it. if you do something other than this its up to the user to edit the macros to match the different setup. we provide the auto square macros as a stock solution and do not intend to support with the Wizard every possible combination that a user could choose when wiring and configuration home switches with Autosquaring. CNC12 of course does support any non stock configuration as we provide the user editable tools (macros, plc etc) to do so yourself. just be aware if you devaite from the stock auto square configuration its up to you to edit your own autosquare macro(s) to match.

OK, I understand what needs to be changed if I deviate from the standard homing macro but if I make the change as shown in the attached image (change Z to 0 in the auto homing sequence) will the existing macro ignore Z homing?