Advanced Search

Hi everyone,I've started developing an I/O board using the Raspberry Pi Pico. The prototype will feature 8x 24V outputs and 16x 24V inputs, communicating over Ethernet UDP with a real-time HAL driver. If everything works well, I plan to develop additional boards with step generation, analog outputs, and encoder inputs.At the moment, things are still evolving—I'm currently having the first batch of 5 PCBs manufactured and have already ordered the necessary components. Communication between the Pico and the real-time HAL is already working. :)I'll keep you updated as the project progresses!

Thank you for the input!

Just got back to the machine.

Was not sure what value to set maxerror to so i started with 0.001. It did pretty much eliminated all overshoot, but i also feel that the P value has no effect anymore. A P value of 5 or 100 have the same response curve.

I tried milling with P=2 and maxerror=0.001 but still got a rpm drop of about 70 revolutions. Also tried P=5 and got a drop of 130 revolutions!

If i up the feedrate while under load i have the feeling i could easily stall the spindle.

Maybe the vfd is faulty?´

Also anything in the VFD setup that slows response will limit the highest stable P term.

Would reducing or disabling the startup acceleration also count here?

I attached a image of halscope with encoder feedback, speed cmd and pid output. The pid is working and trying to combat the drop, so maybe the spindle gearbox is not dynamic enough to respond quick enough? In the image the difference is not so big but again if i increase the load the difference gets much bigger.

Still using the fine cut consumables but much faster cut rates. The slag pops right off now. You can see where I’m getting alittle wiggle around sharp direction changes so I’m not sure going up to 250”/min will be beneficial with the standard consumables.

There is no change, but I think it is worse. Because immediately after starting Linux, there was a warning message.

I ordered an i5 - 2500к processor.
It will arrive tomorrow and I will test it.

JTknives wrote:

Can you pass a message onto the sheet cam guy?

They have an active forum. Ask there
forum.sheetcam.com/

I tried using MesaCT to generae the ini and hal files but upon loading in linuxcnc, it produces an error.

Debug file information:
Note: Using POSIX realtime
./main.hal:31: Pin 'hm2_5i25.0.7i77.0.4.analogena' does not exist
2243
Stopping realtime threads
Unloading hal components
RTAPI_PCI: Unmapped 65536 bytes at 0x7f0b2d806000
Note: Using POSIX realtime

I do not know how to proceed. Kindly advise.

For information purposes,
Drive 0 - x axis
Drive 1 - y axis
Drive 2 - z axis
Drive 5 - Spindle

Regards,
Kelvin
 

JTknives wrote:

I have been searching around and can’t seam to find a dedicated QTPlasmaC sheetcam PP. I looked in sheetcam and found LinuxCNC-PlasmaC but not sure if that’s for the QT. Any help would be greatly appreciated. Thanks guys. 

I suggested to Les a few years ago that he change the name, but it didn’t go anywhere.

Even know the GUI is QtPlasmaC, the component is technically still PlasmaC, so I guess it works? I can definitely see how it’s confusing to new folk though.

Cuts look nicer. Did you change over to 45A consumables as well, or just update everything?

Hello,
I am looking for an XML file for a Beckhoff controller, can you post the file here, I would be grateful. The file you need seems to be at this link:
forum.linuxcnc.org/ethercat/47534-etherc...e-configuration-woes

Can you pass a message onto the sheet cam guy? I noticed that thy have a plasma tool plugin now that has a slick feature for building hypertherm 45xp tools. Well I noticed thy had steel fast and steel quality in the drop down. But I think those are swapped. When I select steel fast it is the speeds for quality and the same is true for steel quality as its the faster speeds out of the manual. I was going to contact them but couldn’t find out how.

Jogging all good now, so paying attention to getting the variable resistor potentiometers to control feedrate and spindle speed overrides.
This was complicated by the fact the Hurco has these pots internally fed with 5 volts, and I am reading the analogue voltage via 7i73 pins that tolerate 3.3volts max. However, addressed that with a resistor bridge. Then I want for the pot controls to also change the gui sliders on the Axis screen.
The attached postgui hal makes that all work, and by adjusting the scale figure can get the mid positions to align with 100%, near enough.
To get that right I have been stopping and starting the Axis gui, over and over without homing the machine and find that this "unrecognised error" message crops up sometimes, freezing the rate sliders. The Gui can stiil be shut down normally using the top right X , and generally on a restart, it works again but would like to know what the cause is.
Thanks
I have never seen this error before until I used the mult2 function in this hal.

Thank you so much. I just tested it out and I do t know what voodoo you crammed into this new program but holy crap. It’s cutting better and way faster than it’s ever cut before. The ohmic is wicked fast and doesn’t even tap the part like it did before. Also I’m using the magic hole feature and it’s cutting these small holes amazing. 1/4” holes come out about perfect with no need to be drilled anymore. I wish I would of upgraded years ago. Huge Thank you to everyone that worked on this.

I’m cutting this at about 160” min which is 2-3 times faster than I was and the results are way better.
 

stkvit wrote:

I converted the bcl-amp output to a differential signal (max485), at a long length it works much more stably and reliably. You should do the same (I understand that your frequency is linear and depends only on the height). A couple more questions, your sensor have temperature stabilization?

I was thinking about differential signals and if there is such a need I will introduce them, we will see after the tests. There was only one obstacle - I wanted to leave the size of the device exactly like most BCL type sensors so that it would fit perfectly in the place designated for it. I did not find a suitable connector convenient to use to accommodate so many cables. I thought about RJ45 but it gave rise to other problems. 

Fortunately, such a converter is not a problem and it can be added even externally along with galvanic separation, which is missing here. 

Of course the temperature stabilization is needed - now introduced very basic and weak, it requires refinement. This still requires a lot of time. I have to collect a lot of measurement data and refine the algorithm but I am prepared for it. The current implementation should be completely sufficient for tests. There are other sensors apart from temperature that are more difficult to control and that spoil the measurement during cutting (dielectric parameters of the gas surrounding the nozzle).

We have built a CNC machine using open-loop stepper motors. The motor drivers are connected to a computer via a breakout board, which is linked using a DB25 cable. Most of the wiring is done using jumper wires, and we have a common ground for all electronic components. The Y-axis is driven by two stepper motors, one for each arm.To improve signal stability, we have added pull-down resistors to each Step- pin of the motor drivers. However, we have observed that the potential difference between the 5V pin and ground pin of the breakout board (powered by an 18V power supply) is only 1.6V. Additionally, when the Y-axis motor stops working, the potential difference between the 5V pin and the Y-axis direction pin drops to 0.06V.Thus, we suspect that the breakout board is damaged. The 5V pin on the breakout board should provide a stable 5V, but since it only outputs 1.6V, the board’s voltage regulator or power circuit may be faulty. The fact that the Y-axis direction pin drops to 0.06V when the motor stops further suggests a power issue or weak signal.Additionally, we suspect that electrical noise is affecting system stability, leading to random motor movements. Interestingly, noise issues only appear when the PC is connected to the breakout board. What could be the reason for the issue? Should we also connect breakout board with a usb cable to the PC for extra power. YOU can view our breakout board specifications in the file attached below. 

Hi Royka in the past you give me a link to a kernel.. the link no more work.. is there a new version of a kernel for the latest linuxcnc? i am on mesa.. rtpreempt 6.1.0-31.


the kernel you link me was :

royka post=299706 userid=31446
Which kernel do you run at Debian 10? "uname -a"
What is the result of "cat /proc/cmdline" on Debian 10 and 12?
What is the result of "cat /proc/interrupts" ?

This kernel I've compiled last week by the way (6.9.0-rc5):
drive.google.com/drive/folders/1L28lG0zD...2XQJx?usp=drive_link




can you please help me.. i make fresh install on the same machine and done everything but the kernel is needed to get it work perfect.... i see that the kernel which came with the latest linuxcnc iso doesnt work like my machine before...


thanks

I've never used rtai, but run latency-history and htop, sort by priority (F6?) and you'll see. I think you could use the same script.
Bad RAM memory could be a cause, usually using 2 ram modules (of the same) is better so it can use DDR. But if one of the two is bad removing one or the other might give a better result.
HDD can also be a cause, if you still use that buy a cheap SSD.
Disconnect any CD/DVD drives, SD-reader units.