If anyone can please help - I cant find any info on what an Out-Of-Band motor (axis) is and what they are used for- Please help.

A good example of an out of band motor use case would be a CNC plasma with a torch height controller.
You have your X,Y,Z axes... then you set your Z axis for zero on your part like normal. Then your THC (torch height control) is also assigned to the Z axis but just for THC movement.
Well this movement for the THC is tracked via the out of band's motor position. While your Z axis is commanded in the GCODE window it will be represented in the DRO whereas the OOB motor will not be reflected in the DRO if the height controller moves it due to an UP / DOWN signal.
Once the file is finished or THC is disengaged, the Z axis movements due to THC are then shoved into the DRO's appropriately to "resync".

This is just one example of OOB usage.

Hi,
another really good use of an out of band motor is for a variable speed pump. In effect you can only jog an OOB, it does not stay coordinated with other axes. But it can of course
be jogged at a certain speed (velocity mode) or a certain 'distance' (incremental mode).

I find this later mode just the ticket to have a pump fill up my beer glass....it pumps 500ml at a time, every time, after all one would hate to over-fill the glass and waste it!

Craig

do you mean in other words the system can handle max 6 axes interpolation the rest can work only as OOB ,my sample is the tool magazine
that in our case its carusale  with 20 tools power by servo
? is that correct?

Hi,
Mach4 can handle six coordinated axes, but each of those axes could have as many a six motors, one master and five slaves.
Thus Mach4 could in theory drive 36 motors simultaneously, in six coordinated groups.

In a more normal machine you might have five axes, one with a slave, thus six motors, which would allow scope for another thirty OOB axes, arranged
in groups of six. Thus OB1 is master with up to five slaves. OB2 is master with up to five slaves etc.

All the motors of OB1, master and slaves will operate simultaneously, as will all the motors of OB2, but OB1 and OB2 are NOT coordinated with each other.

This make Mach fairly capable, but most motion control boards cannot do all of that. For instance my ESS has six Step/Dir motor pairs, say four coordinated
axes and two OB axes. The ESS can drive a spindle with Step/Dir which is counted then as one of the six available motor channels. If however it is run as PWM and On/Off
then it is not counted as one of the six motors, nor in fact is it counted as an OB axis. It is if you like a seventh axis but with curtailed control.

To my knowledge there is no Mach4 motion controller that can do anything like the number of motor that mach is capable of. I think it may be possible to have many
more OB motors with Ethercat, which of course does not require a motion board at all. Ethercat can address up to 100 nodes, say 90 motors and 10 IO nodes, should
be enough for most purposes!

Craig

in pokeys we have 8
actualy i used until now 7
because i had 4axis(not motors ,axiss),one lathh, the hood its also drive by steper and the magazine
only 4 where run simoltanny in Gcode
but now we build the 5 axis that 5 simulate + hood+ magazine
but i don't remember i define it as OOB

Goomba
the ob motor comand from gcode? or only as action acording  event handler?
is there way to wait for ob motor finish position even its OB? from mach?
because i can also get signal from the driver as well