Tweaking Post or other settings to resolve Z axis issue on job start

[dking497GUX]

Hi All,

I'm new to using Fusion 360 for my CAD/CAM.  I have a DIY plasma/router table that uses a Linuxcnc based control called CommandCNC.  This control application and all of the electronics are developed by a company called CandCNC.  Their software of choice is Inkscape/Sheetcam, etc.  for plasma and some 2D routing.  I wanted to use Fusion 360 because of all of it's capabilities and features. They don't directly support Fusion 360, but the owner has recommended to try the LinuxCNC (EMC2) post since their control is based on LinuxCNC.  I've been trying to get the post to work with my table/control.   I'm hoping that someone can help me resolve an issue i'm having.   

After zeroing out the X, Y and Z axes (Z zeroed to the top of the part) and run the G code, the Z axis ignores the tool height and dives straight into the work piece.  I did find a sort of answer that another user posted on reddit, but i would like to fix it with tweaking the post or any other suggestions.

Here is the link to the reddit article:    Z axis issue click here

Please see the G code below and i'll explain how I manually got it to work.

%
(SPOILBOARDMOUNT1001)
(JUST BOARD HOLES 10)
(MACHINE)
( VENDOR AUTODESK)
( MODEL GENERIC 3-AXIS ROUTER PP)
( DESCRIPTION THIS MACHINE HAS XYZ AXIS ON THE HEAD LINUXCNC)
(T1 D=0.25 CR=0. - ZMIN=-0.75 - FLAT END MILL)
N10 G90 G94 G17 G91.1
N15 G20
N20 G53 G0 Z0.
(BORE1)

On the line N20 I changed the Z0 to the depth of the spoil board; so, with it set to  Z.75 the G code runs successfully.

My questions are:

1. How do I need to change the post to correct this issue without manual intervention.?

2. Are there any other settings or considerations i need to be aware of that would allow me to run reliable posts?

Thanks for all of your help in advance, since i'm out of my depth here on this. 

Also, sorry to be so long winded.  

Regards,

Doug

[engineguy]

@dking497GUX 

The G Code is correct, that command line of G53 G0 Z0 is telling the CNC to go to it`s Z axis "Home" position, which is normally the highest point of the Z axis travel, it is in effect a safety command as it sends the Z axis up to it`s highest position before any X/Y moves.

There are two Z0 positions on a CNC, one is the actual Machine Z0 coordinate and the other is the "Top of Part" Z0, it is likely that you have set the machine up incorrectly to the wrong Z0 setting.

[dking497GUX]

Thanks for the quick reply.  I'll take a look at what i have and see if i can adjust the settings.