backtracking a dispenser! need advice!

[ASC]

Hey all, just setting up a new fishman solder paste dispenser as my C axis.  As the C-axis goes positive, the cartridge is compressed and paste gets dispensed into the desired pattern, but when forward motion stops, there is still pressure in the cartridge and the paste continues to poop out and ruin my circuit board!  I am hoping someone can point me in the right direction in a way to rectify this.  Ideally I would like Mach to detect when the dispenser is in use, wait for forward motion to cease, and then reverse the direction of the C-axis a set number of steps/distance to relieve the pressure on the cartridge.  Has anyone had any experience in this sort of situation?

[BR549]

HUM would it not be easier to just tell the Gcode to back up the C  when the  line ends?

(;-)

[ASC]

haha yes it would! My problem is that my programs are running in the range of 5,000 lines and up, lots of arcs and other insanity.  I need a way to automatically put in the code to move the dispenser back, editing gcode by hand intimidates me ( I'm still a n00b when it comes to CNC control, does it show?  lol)

[Tweakie.CNC]

ASC,

Editing your GCode should not be a problem - even using the 'replace' function in 'windows notepad' you can add something like "C-5" after every instance of the code which turns off the dispenser in a matter of just seconds.

Tweakie.

[ASC]

just tried it out and you are right!  Cheers guys, that was easier than I thought it was going to be! woooo!  It's dispensin' time!