Setting up soft limits in UCCNC .. "Logic"

[Kitwn]

Regards Backing off the HOME switch then the only point to me, other than to relocate MACHINE ZERO position is to stop potential false trips if using same switch has limits combined with homing or to square a dual motor gantry.

A precise and detailed description of my own machine!

I love threads like this, I always learn a great deal myself and as I discovered when I took up teaching technical stuff to adults back in the 80s, there's nothing will show up the holes in your own knowledge more effectively (brutally at times!) than trying to explain things to someone else. I now need to swot up on the full details of G54, G55 and other relevant codes and exactly how LinuxCNC uses and saves them.

The difference between machine coordinates and work coordinates is, as Neale pointed out, a confusing one tro begin with but soon becomes one of those fundamental bits of knowledge you don't realise you never knew.

[Clive S]

. I now need to swot up on the full details of G54, G55 and other relevant codes and exactly how LinuxCNC uses and saves them.

Yes this confuses many people. Have you noticed that you can see the machine coordinates and the current G54,55 etc on some GUIs at the same time. In Linuxcnc you can turn them on and off from the view tab.

Ie. If you have touched off your part ie X0,Y0 in G54 you will see the machine G53 at the same time completely different.

http://linuxcnc.org/docs/2.8/html/gc...es/offsets.png

http://linuxcnc.org/docs/2.8/html/gc...ordinates.html

[JAZZCNC]

I now need to swot up on the full details of G54, G55 and other relevant codes and exactly how LinuxCNC uses and saves them.

Probably without knowing it you and many others have actually been using a WORK OFFSET in fact if you have been using 2. These being G53 and G54.

When you HOME your setting G53 ZERO which is MACHINE coordinate system and when you set WORK ZERO you're using G54 WORK OFFSET. Almost all controllers, Mach3, UCCNC, LinuxCnc, even industrial-grade controllers like Fanuc, etc use G54 by default and unless you specifically need to use a different OFFSET say for things like multiple vises with OP1 OP2 type setup or several Fixture Jigs which all have a ZERO point you don't need to know about them.

Most CAM packages are also set up to use G54 by default which is another reason why many users don't actually know they are using WORK OFFSETS.

If you have a large working area WORK OFFSETS makes cutting several different jobs say as in different materials or thickness very easy because of each Fixture as it's own ZERO.