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Author Topic: JOG quality better than code movement  (Read 2840 times)

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JOG quality better than code movement
« on: November 07, 2011, 12:53:41 PM »
Both using the latest version as the latest lockdown version I notice a different behaviour from my machine movement at high speeds from jogging to some code. This happens in all axis.
For example, if I jog at top speed from X=0 to X=200 (more or less) and if I command G0 X200 from position X=0, the movement in MDI line (or running any gcode file) is always with a worst quality (seams at bursts). The computer is good hardware and the windows only have Mach3 installed. Kernel speed is 45000Hz, and this only happens at high speeds. If I lower the motors speeds to +- half this does not happen. I cannot test at lower kernel speed, because in that situation the top speed of the motors would be quite lower.

Can it be a BOB issue (should not be as in JOG the movement is smooth), or this is reported anywere - known issue?

Any ideia?
Re: JOG quality better than code movement
« Reply #1 on: November 08, 2011, 05:07:35 AM »
In the lastlock down version this does not happen. In my last post I have informed that it happens, but I probably did not removed the parallel port driver, so I suspect it is related with the parallel port driver that comes together with version 50.

Offline Tweakie.CNC

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Re: JOG quality better than code movement
« Reply #2 on: November 08, 2011, 10:04:37 AM »
If your slow jog rate is set to less than 100% could this have a similar effect ??

Tweakie.
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Re: JOG quality better than code movement
« Reply #3 on: November 09, 2011, 04:32:39 AM »
Yes, it is the same, but the JOG is always ok.
Running code or MDI input not.

Offline Tweakie.CNC

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Re: JOG quality better than code movement
« Reply #4 on: November 09, 2011, 04:47:04 AM »
Sorry, I didn't explain very well what I was meaning.

Keyboard Jog is at the % rate set in slow jog.

MDI jog or G00 is at the full 100% rate.

Still not sure if I have explained what is in my head.  :-\

Tweakie.
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Re: JOG quality better than code movement
« Reply #5 on: November 11, 2011, 03:40:39 AM »
It is the same thing. Having the jog at 100 or 2 precent is equal, the movement is smooth.
Basically JOG is always ok, "controlled movement" is not. Kernel is at 45Khz. I have also posted a error that at this frequency the charge pump also works sometimes, this all in version 50 and 51 - did not try the 52, but the change log does not refer nothing about this so I suppose nothing was done. The lockdown (version 22) is ok, so this cannot be hardware or bad configuration. This is a Mach issue.

Filipe

Offline ger21

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Re: JOG quality better than code movement
« Reply #6 on: November 11, 2011, 08:29:31 AM »
The driver was changed after the lockdown to give more consistent results for more users.

Imo, Mach3 is at the point where every fix breaks something else. Your best bet is to find a version that works good and don't change unless you find a bug.
Gerry

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Offline Tweakie.CNC

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Re: JOG quality better than code movement
« Reply #7 on: November 11, 2011, 08:35:25 AM »
Quote
Imo, Mach3 is at the point where every fix breaks something else. Your best bet is to find a version that works good and don't change unless you find a bug.

I have a sneaky feeling you are right there Gerry.  ;)

Tweakie.
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