Machine Stutter / Notching Phenomenon

Hi guys, I changed the timings as suggested but I still am getting this, I think it is the machine actually losing steps. Is there any way I can view latency in real time? Does HAL Meter offer this?

If I am losing steps, where do I start in rectifying it? New computer? I see people using much lower spec pcs running fine.

I have another video, I ran at a higher speed and the stutter is slightly easier to pick up, though speed doesn't seem to be Influencing it at all, infarct I would say it's almost smoother at higher speeds.



Thanks

You can plot the base thread time with halscope
or watch the base thread tmax value with halmeter or halshow

Have you tried say moving windows around on
the screen to see if you get more "thumps"?
This would be diagnostic of latency issues.

Hi and thanks for your reply.

I have not, I will try these in the morning when I'm back at the machine thank you.

Hi again,

So I tried your suggestions today.

Whilst running gcode I can see my base thread time hovers around 33k. It occasionally peaks to ~40k

In my .ini I have base as 50k and servo as 100k.

Is this correct??

Currently I'm watching latency test. With like 20 Firefox windows open and dragging one around I'm at around ~33k Base Thread Max Jitter and 26k Servo Thread.

However my last interval for servo is pinned at like 999999.. is that right?!

I think your servo thread is too fast, normally this should be set to 1ms (1000000 ns)

That's what it's set to, shall I increase it more?

Also I checked repeatability with a dial indicator, it's definatley losing steps.

Guess I will try another PC, maybe it's the BoB?

In my .ini I have base as 50k and servo as 100k.

is it 100K or 1000K? (should be 1000K)

It was 100k, but just tried 1000k and it's the same.

I'm leaning towards maybe a faulty BoB. I just powered everything up and I noticed the 5v LED from USB Power (I have it on a old iPhone mains usb charger - 5v) and noticed it dwindling slightly. Could this be an indication of problems? It has a steady 5v however.

Certainly 5V power issues could cause this type of a problem
Do you have a voltmeter to measure the 5V at the BOB?

Note that the servo thread should remain at 1000,000 ns

Hi again,

Yes 5v at the BoB is consistent, i actually pushed the LED with my finger and it corrected so i now suspect a dry solder there lol..........

Now to throw another spanner in the works- i can run the stepconf axis test as fast as i want and the machine moves BUTTERY SMOOTH, no stutters or lost steps. This gives me hope that my setup is ok, but also confuses me as to how im supposed to fix it lol.

Thanks again for helping me i really appreciate it.,

EDIT:

In stepconf i had:

20000
20000
40000
40000

Base Thread 50000

Edit:

Tested those same values in both Axis and Gmocappy and the lost steps is still there