Getting dizzy cutting circles!

[John S]

Lee,
I thought the avatar you entered said it all so I left it, it's a bastard getting crumbs out the computer though.

As regards the arcs thing, it's got to be the most posted about fault on Mach, it's well documented but who reads the docs ?

It's not actually a fault running arcs in absolute mode and relative mode is a choice, like imperial and inches. Some people / systems use one or the other, it's more a personal choice.

One problem with Mach is when you select a machine you load an XML file up for that machine, defaults are mach3mill.xml , mach3turn.xml , plasma .xml or if you have named one for a machine you may have called it router.xml

When the xml file is loaded it tells Mach all the information about the machine, steps per inch, ports and pins etc so you can run many machines from the same computer. However xml's are not consistent to each computer, they should be but they are not.

A classic example is the pulse width in motor tuning, I could give you a xml with the pulse width saved to 5 but when I pass it to someone else here computer can read that as anything from 0 to 6, it very computer dependant.

The same applies for the inc / abs arcs, they can change on install.

Art, when he had control of the program before he sold it on knew this and put a code in for it, they are G90.1 for absolute arcs and G91.1 for incremental arcs.

If you work in incremental arcs like most people then putting G91.1 in the startup line either by hand or get the post processor to do it will always load the right choice.

.

[irving2008]

Lee,
...However xml's are not consistent to each computer, they should be but they are not.

A classic example is the pulse width in motor tuning, I could give you a xml with the pulse width saved to 5 but when I pass it to someone else here computer can read that as anything from 0 to 6, it very computer dependant.
....

Sorry, John, but that make no sense to me. What you are implying is that either each computer reads the same value from the file but does something different with it, or that the value isn't in the file at all and that each computer does its own default setting...

I use XML files for system configuration day in/day out - I have never experienced a situation where two computers read diffeent values from the same XML node on the same file - whats in the file is what gets read, however I could accept that a specific machine uses the value in a different way due to other configuration items.

[John S]

Sorry, John, but that make no sense to me. What you are implying is that either each computer reads the same value from the file but does something different with it, or that the value isn't in the file at all and that each computer does its own default setting...

Possibly it's down to the computer then and not the XML, I'm just a practical big hammer man and don't understand the nuances of programming.

There has recently been a thread on here that proves the pulse width in that Steve Hilton posted to someone [ can't remember who ] about changing it.

Here's some proof,
Download this test XML from http://www.stevenson-engineers.co.uk/files/test.xml and drop it into C:\mach3

Open up the Mach3 loader on the screen and select test.
Then go to Config > Motor tuning and post what the pulse width is. When we have got a few replies I'll tell you what I set it too.

This won't knacker up anything in Mach, it's actually the default Mach3mill xml renamed and a new value saved for pulse width.

The Abs / Inc arcs don't change once set but it depends on who issued the original XML. If you open the test one up which as I say is a copy of the default one it's setup for absolute arcs but 90% of users use incremental.

Unless you understand this then 90% of new users get caught out because the program is in the wrong units as default.