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Author Topic: Mach4 jogging output.. diagnostics screen  (Read 370 times)

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Re: Mach4 jogging output.. diagnostics screen
« Reply #10 on: February 26, 2019, 07:33:24 PM »
Yeah, I can do that.  16 is the number of steps that moves my Z or X by 0.001 inch.  So 16 is correct.
I deleted the intermediate steps from the log, but they showed that the axis ramped up and down in speed, so the acceleration parameter does work.
 
It doesn't matter how long I wait between jogs.  I get the same result.  I have also tried slowing down the acceleration which also produced the same result.

I'll try that tomorrow.
Re: Mach4 jogging output.. diagnostics screen
« Reply #11 on: February 26, 2019, 07:48:21 PM »
Hi,
maintain the acceleration as high as your steppers allow. That gives your machine the best possible chance
to maintain any given toolpath. Reducing velocity is  beneficial if your machine is struggling to keep to a given
toolpath.

How long have you had the UC100?

When you got it did you have to install the CNCDrive USB driver?

I'm beginning to think there is a problem with the UC100. There are a ton of Chinese UC100 rip-offs on
EBay, Amazon etc. Is it possible that you have inadvertently picked up such a device?.

My understanding is that genuine UC100's require a special driver be installed on the PC prior to the UC 100 being
able to communicate with Mach. The Chinese made units rely on the standard Windows USB drivers and require no
installation on your part.

I would recommend that you contact CNCDrive or the CNCDrive forum to get some help.

Craig
My wife left with my best friend...
     and I miss him!
Re: Mach4 jogging output.. diagnostics screen
« Reply #12 on: February 26, 2019, 08:18:55 PM »
I bought 2 UC100s about a year ago.  I got them from DPP based on Sherline's suggestion, and they are made by cncdrive.
Yes, I installed the software usb drivers from cncdrive.  I did have to install special drivers using their installer.
Since Mach can operate my steppers, and gcode runs ok, I'm confident that I have real UC100s.
Once, when I started Mach, cncdrive downloaded an updated firmware to the UC100.

I have turned morse tapers using Mach's lathe wizards to make tool holders for my mill, and that worked perfectly.
What doesn't work is jogging small increments, like .001 or .0001 inches, and backlash.  So I can't touch off using my pendant, or the screen jogs.

There are a few other minor bugs I found in Mach, like when changing a motor parameter on one axis, the other axis becomes slaved to the motor I just changed.  IE: sometimes, not always, changing the max feed rate will link the Z and X axis together until I restart Mach or hit the reset button a few times.  Thats pretty weird, Mach4 gets confused!

If I set up a dial indicator to check Z movement, and then do a lot of jogging Z back and forth, the axis does not track correctly and Z ends up in the wrong position.  But if I issue G0 Z0, it returns to its 0 position correctly.  I can't trust jogging, but gcodes seem to work properly.

For instance.  If I run gcode like this:
g0 z .001
g0 z .002
g0 z .003
...
g0 z .010
Z axis moves correctly.
then
G0 z0
returns to the Z position correctly

By the way, cncdrive has been 0 help, and just say its Mach4's fault. 

I think I will try the motion simulator tomorrow and see if the same thing happens.

I appreciate the help and suggestions :)

Bill
Re: Mach4 jogging output.. diagnostics screen
« Reply #13 on: February 26, 2019, 08:49:03 PM »
Hi,

Quote
Yes, I installed the software usb drivers from cncdrive.  I did have to install special drivers using their installer.
Since Mach can operate my steppers, and gcode runs ok, I'm confident that I have real UC100s

Good news.

I use Machs 4 axis mill profile, or at least an individualized copy of it, and I have no trouble jogging in increments
down to 0.001 mm, ie 1 um, the limiting resolution of my machine. Its not impossible that the lathe profile differs somehow
but IF that were the case I imagine every man and his dog would be complaining about it. To my knowledge that is not the case.

Quote
There are a few other minor bugs I found in Mach, like when changing a motor parameter on one axis, the other axis becomes slaved to the motor I just changed.

I have not encountered that problem either throughout a number of builds of Mach. I have just within the last few minutes
downloaded and installed build 4095. Time will tell if a bug has crept in since the previous 3084 build I had.

Quote
By the way, cncdrive has been 0 help, and just say its Mach4's fault. 

To be fair to CNCDrive Mach4 is a competing product to their own software. Having said that I have heard several users
make similar comments....'The fault is in Mach4....not our controller or plugin'.

Quote
So I can't touch off using my pendant, or the screen jogs

What pendant do you use? Even if the pendant was faulty somehow it still would not describe the behavior of the button jogs.

The only other question I have is 'does the UC100 plugin have the numerical resolution to enact such small increments?'.

Even if the jogging problem can be solved you still have the problem of backlash compensation. At this stage I'm 95%
confident CNCDrive devices DO NOT support backlash comp in their Mach4 plugin.

Craig
My wife left with my best friend...
     and I miss him!
Re: Mach4 jogging output.. diagnostics screen
« Reply #14 on: February 27, 2019, 01:41:51 PM »
Craig,

I just had some time to do some more experiments.
I took your suggestion and lowered the jogging rate to 1%
At 1%, jogging works perfect from the onscreen buttons.  At 3% it fails, and at 2% fails sometimes.
Perhaps this is a communication problem with the speed of the USB causing lost or garbled coms from the UC100.

Also, at 1%, the backlash comp works!  It seems the backlash problem was actually caused by the jogging problem.
With the backlash set to .0034, the positioning is right on the money according to my dial indicator.  Without it, positioning is off by .003+ when changing directions.

So, I have proved that the UC100 does do backlash compensation with Mach4.
This was verified by my dial indicator on the Z axis tested with jogs of .001 .010, .1, and 1 inch travels in both directions.

But, there is still a problem that happens with the pendant. (VistaCNC P1A).  If I click the pendant in one direction, and back up a click while the axis is moving, it generates way to many pulses and the axis won't stop.  I am going to assume that this problem belongs to the pendant, and not to Mach4 or UC100.  It could also be speed problems with the USB ports.  Unfortunately, Mach4 is licensed to my laptop, so it will be dificult to test that idea with another computer.

So now, I can use my pendant to accurately touch off on my work piece. 

Thank you for your help.  (of course any more ideas and suggestions are welcome :)

Bill
Re: Mach4 jogging output.. diagnostics screen
« Reply #15 on: February 27, 2019, 02:42:37 PM »
Hi,
can you confirm what jog mode (continuous or incremental) that you are using.

I have the identical pendant and what you have described sounds like it is jogging in continuous (Velocity) mode.

Craig
My wife left with my best friend...
     and I miss him!
Re: Mach4 jogging output.. diagnostics screen
« Reply #16 on: February 27, 2019, 04:18:03 PM »
Craig,

I used incremental mode with the pendant and Mach with both set to 1% jog rate.  My pendant reverts to 50% everytime I start up Mach or do a reset.

Works fine as long as I don't reverse the pendant wheel while the axis is moving.

Bill