Can't run the job

All things related to the Centroid Acorn Plasma system.

Moderators: cnckeith, Joey

TAS99
Posts: 33
Joined: Thu Jul 21, 2022 7:16 pm
Acorn CNC Controller: No
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: none
DC3IOB: No
CNC12: No
CNC11: No
CPU10 or CPU7: No

Can't run the job

Post by TAS99 »

I have a new DYI plasma cutter and I've completed all the set-up procedures and I have cut a simple job but the one I'm referring to here has problems.

The job starts, the torch plunges rises and starts to cut a couple of inches and then for some reason the z lowers and trips the mechanical torch height switch. I get a message about a torch collision so I raise the Z axis to clear it hit run and it goes a couple more inches until I get the same problem again and again.

I'll include the beginning part of the code if it's any help.

Any help would be greatly appreciated.

Tom

;Filename: Big Foot UpperOuitline Only.tap
;Post processor: Centroid Acorn Plasma THC.scpost
;Date: 01/02/2023
G20 ;Units: Inches
G90
M65
;Part: Big Foot
;Operation: Outside Offset, UPPER, T1: 18GA Steel
G0 X7.882 Y18.3899
M61
G2 X8.3864 Y18.1888 I0.1517 J-0.3528
G3 X8.4431 Y18.2019 I0.0271 J0.0117
G1 X8.4287 Y18.4901
G1 X8.6176 Y18.0714
G3 X8.619 Y18.0686 I0.0269 J0.0122
G1 X8.7206 Y17.8962
G1 X8.7182 Y17.8946
G1 X8.6692 Y17.9148
G3 X8.6362 Y17.9076 I-0.0113 J-0.0273
G1 X8.5879 Y17.8551
G1 X8.5872 Y17.8544
G3 X8.5259 Y17.7771 I0.9569 J-0.8226
G3 X8.399 Y17.5895 I2.4859 J-1.8178
G3 X7.6369 Y15.8985 I6.1793 J-3.802
G3 X7.2101 Y13.5805 I9.9892 J-3.0376
G1 X7.187 Y13.2602
G3 X7.1869 Y13.2581 I0.0295 J-0.0021
Joey
Posts: 465
Joined: Tue Aug 17, 2021 10:51 am
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: none
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No

Re: Can't run the job

Post by Joey »

Sounds like the THC is on and lowering the torch during the cut. Is the THC on for this job? Does this happen during a straight line cut with THC on? Has this material , profile and it's target voltage setting worked on other previous cuts and jobs?
Please post a fresh report.
TAS99
Posts: 33
Joined: Thu Jul 21, 2022 7:16 pm
Acorn CNC Controller: No
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: none
DC3IOB: No
CNC12: No
CNC11: No
CPU10 or CPU7: No

Re: Can't run the job

Post by TAS99 »

Yes, I believe that is what's happening.

As I said, it's a new DYI plasma cutter and I did cut a couple of simple jobs to check it's operation. A 12" circle, some straight lines and squares and they all cut as expected.

One thing I failed to mention is that those test cuts were all cut with no water in the tray. The latest cut that haven't worked were done with water in the tray.

This morning I tried a simple 12" cut along the X axis with water in the tray and had the same failure, ran a couple of inches then the failure. I tried to attach the report but it's 21+MB and too large. There seem to be a lot of text files using a lot of space so I've broken it into 2 .zip files which I hope makes sense.

Regards,

Tom
Attachments
Report B.zip
(9.04 MiB) Downloaded 1 time
Report A.zip
(9.48 MiB) Downloaded 1 time
TAS99
Posts: 33
Joined: Thu Jul 21, 2022 7:16 pm
Acorn CNC Controller: No
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: none
DC3IOB: No
CNC12: No
CNC11: No
CPU10 or CPU7: No

Re: Can't run the job

Post by TAS99 »

Something I just noticed.

Looking at the Acorn Simplified I/O PLC Diagnostics screen I see that the Plasma T IN is always green. If I pull the wire off the Ohmic Retaining Cap it goes red. It seems the system is seeing the torch always in touch with the workpiece.

Any ideas why?

Tom
Joey
Posts: 465
Joined: Tue Aug 17, 2021 10:51 am
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: none
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No

Re: Can't run the job

Post by Joey »

Good news, Looks like your target voltage is set way to low for the material your cutting. Easy Fix. Just run a straight line cut with THC Disabled. Watch the Voltage readings During the cut and set that voltage as your Target volage. Did you run the Calibration Job For the THC? You may need to Confirm and adjust the each profile's target voltage to what your machine, materials, environment requires. With The Target Voltage for the THC being set very Low the THC is bringing the Z/torch closer to the material to Better match the Actual voltage to the set Target voltage.

I've Attached 2 pictures of your plot's from failed cuts. The Yellow Line at the Top is the Voltage during the cut. The light green flat line is your target voltage. You can see how high the actual voltage is compared to the target voltage. The Orange line is the THC enable coming on. The Blue is your XY velocity. Once your XY velocity comes up to speed the Orange THC Enables. The Red line is the Z movement reacting to the THC. You can see that once the orange THC enables the Red Z line dives to lower your Actual voltage to the Target voltage.
Attachments
TAS99.PNG
TAS99 Plot2.PNG
Joey
Posts: 465
Joined: Tue Aug 17, 2021 10:51 am
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: none
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No

Re: Can't run the job

Post by Joey »

The Torch touch issue could be Material lodged inside the torch tip. Especially with the recent Bad Target voltage run I wouldn't doubt that something found its way inside the consumables. Try and Cycle the test fire button on the VCP to Clear any debris out. If that doesn't work take apart and wipe off the consumables.
TAS99
Posts: 33
Joined: Thu Jul 21, 2022 7:16 pm
Acorn CNC Controller: No
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: none
DC3IOB: No
CNC12: No
CNC11: No
CPU10 or CPU7: No

Re: Can't run the job

Post by TAS99 »

Great!

Adjusted the voltage and replaced the shield and that seems to have solved the problem.

I have a question on the torch calibration. Is the voltage recorded (I used 1/4" steel for the test) the same for all thicknesses of material or does each thickness have it's own voltage.

Thanks for all the help.

Tom
Joey
Posts: 465
Joined: Tue Aug 17, 2021 10:51 am
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: none
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No

Re: Can't run the job

Post by Joey »

Good to hear 👍

Each material Has a specific voltage at a given Cut Height.

3 factors can affect voltage.

1. Material type /thickness 2. Cut Height. 3. Feed rate.

If you change any of the 3 factors in your profile you should adjust your target voltage for that profile.
ShawnM
Posts: 2190
Joined: Fri May 24, 2019 8:34 am
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: 7804734C6498-0401191832
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: Clearwater, FL

Re: Can't run the job

Post by ShawnM »

When you do the torch calibration you have to select the material you are using for the calibration from the profile manager. If you don’t then your machine will never cut any material correctly. All this is in the plasma manual. You have to do the calibration FIRST before you do any other cutting. Please take some time and read the new Acorn Plasma Manual.

https://www.centroidcnc.com/centroid_di ... manual.pdf
TAS99
Posts: 33
Joined: Thu Jul 21, 2022 7:16 pm
Acorn CNC Controller: No
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: none
DC3IOB: No
CNC12: No
CNC11: No
CPU10 or CPU7: No

Re: Can't run the job

Post by TAS99 »

I guess my question wasn't clear.

I did follow the procedures in the manual and did the calibration on .25" steel. I assume the voltage was set in the profile for that size and type of material. My question is, do I have to run the calibration program on each new type of material. For instance, if I now cut 18GA steel and load the profile for that type do I have to run the calibration program for that profile?

If that's the case then I can understand why I'm having voltage problems.

Tom
Post Reply