Re: [CAD_CAM_EDM_DRO] Re: Servos and EMC PID tunning.

ruzip wrote:

>Thank you for all the input.
>Router would be Thermwood style type, trimming plastics and high
>density foam. I'm thinking about ball screws and precision of about
>0.001", rapid feed rate of 500in to 750"/min , cutting area 4' by 6',
>air spindle.(unregulated.)Starting with 3-axis and later on moving to
>5-axis.
>Most likely will be moving bridge vs moving table. I hope this will
>shed some light. Could you please advise more on the plotting/PID
>tunning in EMC?
>
>

Six foot ballscrews are not going to work, period, unless you use
rotating nuts,
and the screws are clamped to the frame. You might look at rack and pinion
and toothed-belt drives as a simpler mechanism.

EMC has a "logging" facility, you just pull down a menu (Settings, I think)
and then click on log, and turn on logging for the axis most recently
selected
on the screen. You then move the axis with a jog button, and stop the log.
This creates a file on the disk with position and velocity samples at the
axis update rate. If the right software from the CD has been installed
(you may have to manually add it) it will automatically re-parse the
log file into a format for that graphing software, and display the chart.

In the EMC doc directory (normally /usr/local/emc/doc) is a file,
emcstripchart.html, that has detailed instructions of all this.

Jon