6040Z controller

[RichardR]

Not quite ready to do any cutting, I need to understand how to set coordinates, also I need to fit a sacrificial board and do a levelling sweep which will be good practise, I think a probe plate would be a good idea, then I would know the exact distance the top of the tool is before I start any job, all this will take me a little while.
It's a shame I did not get the CD with it as I understand it has some test programmes which would probably have given me some idea of programming jobs.

[JAZZCNC]

Not quite ready to do any cutting, I need to understand how to set coordinates, also I need to fit a sacrificial board and do a levelling sweep which will be good practise, I think a probe plate would be a good idea, then I would know the exact distance the top of the tool is before I start any job, all this will take me a little while.
It's a shame I did not get the CD with it as I understand it has some test programmes which would probably have given me some idea of programming jobs.

Richard, you are along way from needing a probe plate, it's not just a case of pluging in the probe plate. You need a macro that works out the tool offsets and some other magic behind the scenes, you will also need a modified screen set.
Also you will be better learning how to set it manually as the probe plates are not always possible to use on some jobs so understanding how it all works is worth the time it takes to learn.

Now regards the movement and whether to use MM's or Inch then it doesn't matter because if your Steps per setting are wrong they will be wrong for both. It's also more involved because you will have convert metric pitch to imperial which uses turns per inch.

The steps per setting isn't something you can guess at, it's a calculated figure based on several components like I mentioned in my last post. If it's wrong by even a few digits then it will affect the accuracy. If you don't know the ballscrew pitch and the micro stepping so it can be calculated then you have to use the measurement method like I showed you. The accuracy of the Steps per then depends on how accurately you measure the distance it moved, measure it wrong and it will move the wrong distance.
This is the Same whether you use Imperial or Metric units so changing to INCH units won't make a jot of difference. It will still be wrong in either units.

Clive's suggestion to use G20 for inch is a workaround if you are using imperial G-code but it's less than ideal if you are using on a machine set for Metric units because it only takes into account the coordinates and not the feed rates. To see this in action try one of the G-code files included with mach3 like the roadrunner.
This code was written for Imperial units and if you run it on a machine set in metric units using G21 then it will cut very small, 25.4 times smaller to be precise, because when it commands a move like X10 it actually means move X 10 inch but instead will move 10mm.

Now if you use Clive's suggestion and type G20 this will put you into Imperial units and the size will be correct as X10 will move 10inch but what it doesn't do is take into account the feed rates. The imperial code will command a feed based on imperial units so lets say it calls for F100 it actually means move at 100 inch/min ( 2540mm/min) but because your system is set and tuned to metric units the feed will actually be 100mm/min and the G20 code doesn't do anything to change this.
To get around this and use imperial code the best approach is to create another separate profile with the machine tuned for imperial units. Then when cutting imperial G-code you just load this profile and all will work correctly.

If you would like me to explain how the coordinate systems work and how to setup cutting a job just ask.