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Author Topic: Need help with Constant Velocity  (Read 2073 times)

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Need help with Constant Velocity
« on: July 06, 2014, 02:56:42 PM »
Hi guys,

I converted a chinese router from NCstudio and steppers to DMM servos and Mach3.  It all works perfectly except that I can't get constant velocity to work.  There is a pause between every line of Gcode, not a long pause, but enough to make it jerky. It is driving my nutty...

XYZ all are set to the same acceleration (400mm) and speed.
Constant Velocity is on, and G64 appears in the first line of my Gcode.

My machine: DMM servos with DYN2 drivers, Mach 3 with Ethernet Smoothstepper.

I use Mastercam with the mach3 pp, but the Gcode does not seem to be the problem.  Even basic test code pauses on all the lines.

Anyone have any ideas?

Offline ger21

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Re: Need help with Constant Velocity
« Reply #1 on: July 06, 2014, 04:17:28 PM »
Turn of CV Distance and CV Feedrate on the Settings page, and all other CV options in General Config. The only option you want is "Stop CV on angles", and set it to 89.
Gerry

2010 Screenset
http://www.thecncwoodworker.com/2010.html

JointCAM Dovetail and Box Joint software
http://www.g-forcecnc.com/jointcam.html
Re: Need help with Constant Velocity
« Reply #2 on: July 06, 2014, 04:38:40 PM »
Ya, I already had all the options turned off.  I enabled "Stop CV on angles" but it didn't make a difference.  I am pretty new to this so maybe I'm making a dumb mistake, but it seems like everything is correct.  I attached the Gcode that I am using to test it.  It is a combination of arcs and line segments to cut an irregular shaped pocket.  No matter what I try, it always stutters from line to line in the gcode.

Thanks,
Tony


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