Boxford v190 cnc

[John11668]

Should I be looking at my "Jitter" readings
Until this thread started I did not even know I had any ????

[Doddy]

Crazy high = ??, out of curiosity.

[clutchslip]

Hi Doddy.

With everything I can shut down in bios shut down, excepting a pair of rear panel usb ports, with the machine at IDLE, I have 'Max Jitter' figures of Servo 122,194 and Base Thread 52,639....

[depronman]

Hi Doddy.

With everything I can shut down in bios shut down, excepting a pair of rear panel usb ports, with the machine at IDLE, I have 'Max Jitter' figures of Servo 122,194 and Base Thread 52,639....

That is very high
I think on the HP slime PC I’m seeing 15,000 to 34,000
If was thrashing the pc. Gear display running and on internet opening and closing web pages etc

I have set max jitter in the linuxcnc configuration at 50,000 to be on the safe side

Paul


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[depronman]

Crazy high = ??, out of curiosity.

You should be looking for < 40,000
On a lathe a CV little higher will not hurt
You are running the same HP pc as I will be using (yes). If so then the max jitter is really quite low
Can likely be improved with an external graphics card as linuxcnc is not recommended with onboard graphics which share system ram
But having said that I’m getting quite low max jitter readings anyway so I think all will be ok

It’s an option from the linuxcnc menus to run test max jitter
Set it running then abuse the pc as best you can and come back to the results after about 10 mins and use the result displayed in your linuxcnc config
What it actually does is inform linuxcnc how much resource is available to process things. When it runs out it would be bad so it limits movement speed to a slower love per second to fit within the available resources
You are not going to hit this on a small lathe as first only two axis are being moved at any time and secondly the steppers are not micro stepping down to really low values. I think I run mine at 4 micro steps which means one Rev of motor (4mm true movement) is a total of 800 pulses
You can imagine as the micro stepping is increased, some run 64 micro steps, that the number of step direction pulses increase very quickly for the same amount of physical movement
Then
Multiply this by three axis movement potentially all at the same time on a mill and you can see that pc resources are a lot more critical on a mill than a lathe

Paul


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[BernieNUFC]

Anyone tell me what these buttons are for please?

[depronman]

Anyone tell me what these buttons are for please?

I would think trip reset buttons for various thing
Maybe axis movement is one. Spindle / cutter rotation would be another

Paul


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[depronman]

Any change of a picture or two of the front of the machine please


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[BernieNUFC]

Mine is identical to this

[depronman]

So a slightly newer version than mine is
What does the blue button at the large section of the control panel do. Mine does not have that

Paul


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