Joint 3 Following Error

Any one know what this refers to? 1/4 into the run this shows up & stops the mill

It mean emc ask for movement and the encoder or stepgen did not move enough to be within the max following error specification.
Without more info we can't help anymore then that.
for instance are you using servos or steppers ( I bet steppers) could be your acceleration or max velocity is too high.
are you using software stepping or hardware stepping?

Using a sherline lath. Steppers i'm assuming.
The parts I'm milling are very small. 0.5mm ball nose with 25% overlap. Need to bring out detail in the piece. The mill is very new. Backlash seems to be non existent. But that could still be a problem. Is there some way to adjust the following error specification?
I've slowed the speed down to a crawl but still have the problem.

I'm not sure I understand your question about software or hardware stepping. I use a Rhino CAM software for the g-code.

Great information!! I sort of have an understanding. Is there a translation for simple folk like me?

See the problem for us is your giving us all most no information.
It's like saying my car stopped running - whats the problem?

Is this stock sherline controls ? sftermarket ?
What version of EMC are you using?
If you are using AXIS, look for the help button. select 'about AXIS' and it should tell you the version of EMC
Are you familiar with EMC configuration files? can you post them?
Is this a new problem or just came about?

If this is steppers then the problem most likely has always been there and need configuration changes.
If servos then physical problems such as the ways not moving freely could do this.

changing the following error setting will change the accuracy of the machine.

Now you know how I feel. Joint 3 following error???Lots of possible problems nothing definite.

Yes I do. Many of EMC's messages are cryptic.
Joint 3 by the way is most likely the a axis on a mill.
Do you have an a axis?
Are you using UBUNTU operating system? do you know what version ?
earlier you mentioned a sherline lathe then said mill. Which is it?

Sorry, It is a mill. Yes I do have an " a" axis. I use the Ubuntu operating system 10.04 LTS The mill is stock Sherline. As for the EMC software. It is Axis version 2.4.3