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Stagecraft
11-26-2013, 10:32 AM
We recently upgraded our PRT Alpha with the retro gantry and 7.2 geared motors on the X and Y.
We've seen a substantial improvement in cut quality but in some areas a real drop in speed.
I'm having issues with the VR settings for the JOG command. As things are at the moment, I find it a lot faster using a MOVE HOME command instead of JOG HOME, it's even faster exiting to keyboard mode and using Ctrl + arrow.
The glacial pace of the jog ramping hasn't been an issue with one-off jobs but we've just landed a large, intricate, repeat job that is really bogging us down.
FWIW I've tried adjusting the VR settings for jog but so far I can't see much of a difference.
Am I missing something obvious? :confused:
Thanks if you can assist! - Boyd

Brady Watson
11-26-2013, 10:37 AM
Post a screenshot (Alt+PrtSc) of your VR AND JS settings.

-B

Stagecraft
11-26-2013, 11:01 AM
Thanks for the reply Brady, I'll do that at the next sheet change as the Bot is currently running. (press START...wait 90 minutes, repeat...)

blackhawk
11-26-2013, 11:40 AM
Boyd - Are you using a Vexta drive that you purchased from Shopbot? Shopbot does a special configuration with the Vexta drives that they sell. I ran into this when I bought a drive off Ebay.

Stagecraft
11-26-2013, 12:47 PM
Brady here's the current settings:19406

19407

Stagecraft
11-26-2013, 12:55 PM
Yes Brad, these were ordered direct from Shopbot.

srwtlc
11-26-2013, 01:34 PM
Boyd, those are messed up! Either try resetting those to the defaults or try something like this for defaults and adjust a little from there. Once you get something you like, save them out with 'US'.

Your jog ramp rate is what is really screwing up your jogging. Try the default of .2 for both the move and jog ramp rate and adjust from there. I like my jog ramp a bit more crisp so I run .08. Also, to make the keypad move/ramp a bit less sloggy, try .15 to .12. Slow corner speed is pretty low, but I don't know whether you're doing 3D or cutting plywood and that makes quite a difference. Your z axis move ramp could be set the same as the XY move ramp, unless you're running that way for some other reason.

Brady has a good ramping tutorial here (http://www.shopbotblog.com/index.php/2008/03/a-ramping-the-vr-command-and-how-to-tune-your-tool-for-maximum-performance/).

Stagecraft
11-26-2013, 01:41 PM
Thanks Scott I'll give it a try.
I think I may have been playing around with my ramp speed and ignoring the ramp rate...my brain hurts.
Will know the results in another 45 minutes ;-)

Stagecraft
11-26-2013, 03:03 PM
Mucho better Scott, thanks again! - Boyd

Brady Watson
11-26-2013, 03:29 PM
Glad you got it sorted.

-B