Centroid acorn home Z axis only

[mcmental]

Hi there currently installed centroid acorn on my mates 3 axis mill, we set the machine on its maiden voyage last night and things seem to be going well, just wondering if there is an option to home individual axis’s rather than all 3 of them? We seem to be having to home after we run a program even if repeating the same program, if we don’t we automatically get error exceeded z limit.
Thanks

[acourtjester]

Not sure if this will help but some software packages have a do not home when powering up. It does not affect the home/limit switch action. Another thing I found with my 3-D printer software, it I tried to run one g-code after another it screwed up the homing function. I found if I sent a G90 after each end of G-code it worked fine for the next operation.

[robertspark]

the centroid acorn is very new to plasma, and I'd expect not many users would have one installed. Appreciate that this is a mill application, but it may be best to ask on the centroid forum, as you will probably get a better + quicker answer:
https://centroidcncforum.com/

[mcmental]

Cheers Robert

[cnckeith]

hello. Yep. the home sequence is just a g code program that is user editable.
"cncm.hom" is the program to edit.

with the Acorn Plasma CNC controller you can use a Home position or not. some users like to have the machine home out and use a machine coordinate system along with a work coordinate system while other just want to use a work coordinate system. see "homing methods" on page 9
https://www.centroidcnc.com/centroid_di ... manual.pdf

when you push cycle start to start the home sequence cnc12 simply runs the g code program "cncm.hom"

so to change the action of homing, open it with notepad ++ and make the changes you would like.

the home program uses these codes. M91/2 and M26

M92/Z L1sends an axis to seek the home switch in the positive direction then backs off to clear the switch.

M26/Z set the home position at the current position (in the mill operator manual they are described with examples)

a typical auto homing program looks like this.

M92/Z L1
M26/Z
M92/Y L1
M26/Y
M91/X L1
M26/X

so if you want X and Y to auto home but Z to just home out at the current position simply comment out the first line with a semi colon.
like this.

;M92/Z L1
M26/Z
M92/Y L1
M26/Y
M91/X L1
M26/X


its also interesting to note that the cncm.hom program is auto generated by the Acorn Plasma setup Wizard based on the selections you make.
so its usually best to use the Wizard to customize the home program, but every once and a while a user might want to customize the home program to do something non standard that the Wizard wont do. in that case you simply edit the home program yourself, be sure to set the wizard to "custom home program" so it wont re write you customizations the next time you use it.

all Acorn related documentation is here.
https://centroidcncforum.com/viewtopic.php?f=60&t=3397

see the Macro Programming guide for more info and examples of custom home programs.

and a Acorn Plasma specific forum as been set up for free tech support is here:
https://centroidcncforum.com/viewforum.php?f=65

[cnckeith]

just reread original post and its a mill! ) everything i wrote applies as well to the mill. fyi...our Acorn Mill and Lathe support forum is here: https://centroidcncforum.com/viewforum.php?f=60

[adbuch]

Not sure if this will help but some software packages have a do not home when powering up. It does not affect the home/limit switch action. Another thing I found with my 3-D printer software, it I tried to run one g-code after another it screwed up the homing function. I found if I sent a G90 after each end of G-code it worked fine for the next operation.

I've got the Centroid Acorn with CNC12 running one of my cnc router tables - Avid Pro 4824. The one thing I don't like is how long it takes to do the homing cycle at startup. Very slow compared to my other Avid Pro 4848 with Mach3 control. But once it is homed, then everything is great and I feel it is more reliable for multi-tool programs than Mach3.

I think my 3D printer homes at the start of every new program. It does it automatically, so I have never experienced the problem Tom has with the different G-code files one after the other. I guess it depends on the particular printer.

David

[acourtjester]

I have 2 Anycubic printers, the one with that problem is the Vyper. It does a great job but using a Raspberry via wifi connection, when I send a second start g-code to print it homes funny. If I send a G90 before telling it to do the next g-code it homes just fine which is odd as the ending for the g-code has a G90 in it put there by the slicer. It is a simple work around.

[adbuch]

Tom - I have a similar problem with the post processor for my cnc turning center. I create the solid model, tool paths, etc. using Mastercam, then post the g-code. After that, I always have to edit the g-code and manually enter a few G commands before sending the g-code to the machine. One in particular tells the turning center to put the spindle in hi range. If I don't to this manually, then the machine will not run. This could most likely be corrected by some editing to the Fanuc post processor, but I have never taken the time to try to learn to do this - and it is just easier for my to manually enter those two G commands. So another "Work Around".

David

[acourtjester]

Ah yes the tech world, it can put some pebbles in our path, but asked if we would like to do without it, less than a nanosecond reply "NO"