How to setup a 4axis gantry plasma machine using gmoccapy?

Hi, how can I setup a 4axis gantry plasma machine using Gmoccapy?
I have 1 motor runing the X.
2 motors running the Y.
1 motor running the Z.
1 motor driving the rotary.
Linuxcnc v2.7.8 Debian.
Is it possibe to use 2 steppers for a 2stage Z travel?
Thanks in advance.

To start with, you need to upgrade to master to get the gantry features to run the 2 motor axis, if you are running a Mesa ethernet card you will need to install the preemptive kernal befiore installing Master. You may need to upgrade your PC as I found my 32 bit PC could not cope. The mesa THCAD will do the torch height control at a very low price so their hardware is a good option.

Then this recent thread will get you going and includes the config files.

forum.linuxcnc.org/38-general-linuxcnc-q...other-plasma-install

I'm working on a scratch build plasma cutter using a Mesa 7i76e ethernet card and THCAD and am hoping to get a gantry running next weekend but the table is a fair way off.

Your table looks nice.

And this thread shows you how to install the preemptive kernel.

forum.linuxcnc.org/9-installing-linuxcnc...ng-uspace-for-master

Hi rodw.I have installed the preempt kernel but now I'm confused about selecting the right branch from this link:
buildbot.linuxcnc.org/
Shall it be Wheezy (realtime with RTAI)
architectures: i386 under the "master branch development" ?
The table isn't that nice. There are many mistakes you can't see.

emad wrote: Hi rodw.I have installed the preempt kernel but now I'm confused about selecting the right branch from this link:
buildbot.linuxcnc.org/
Shall it be Wheezy (realtime with RTAI).

If your OS is Wheezy and your Relatime is PREEMPT-RT then the version you want is "Wheezy (uspace: realtime with RT-Preempt, and simulation)"

Are you actually using a Mesa Ethernet card, though?

Andy has answerd the question. Just to clarify you only need the preemptive realtime kernal if you are running a Mesa ethernet card.
I'm using a Mesa 7i76e. On my old 32 bit PC, the latency shot to over 200,000 with the preemptive kernal so I bought a new 64 bit PC.

This is another recent thread that talks about recent PC hardware that has a couple of suggestions from PCW at Mesa (and others) that I used for guidance when selecting the 64 bit Celeron PC I settled on.
forum.linuxcnc.org/38-general-linuxcnc-q...7-any-good-usff-pc-s

I was unable to get the internal wifi card working and am using a USB wifi dongle using Wheezy but I expected to do that based on what PCW said on the thread above. I think native support for the Wifi card is available in Jessie.

andypught:If your OS is Wheezy and your Relatime is PREEMPT-RT then the version you want is "Wheezy (uspace: realtime with RT-Preempt, and simulation)"
Are you actually using a Mesa Ethernet card, though?


My OS is Wheezy and my realtime kernel is the preempt-rt-as rodw suggested- I have installed linuxcnc-dev-uspace from apt.now the Lcnc version is 2.7.8.The max jitter is too high now and I can't upgrade my PC.
I don't use any mesa cards.

Shall I install the RTAI kernel instead of the preemptive kernel for driving the 4axis gantry X Y Y Z A? Or just keep the current kernel install?

Roll back to the normal Wheezy live CD distro and install master to get the gantry features.

Thanks for paying attention rodw. I'll make a new install and tell you the results.