Pressure Advance seems to not be working.

Phaedrux

Can you send an M122 after a print? I'm curious to see if you have any hiccups. There may be skipped steps due to the high retraction speed set and high max extruder speed. It may be trying to go faster than the step pulses can be generated. Or the motor may be trying to go faster than the back EMF will allow.

Either way, you may want to try reducing the retraction speed and max extruder speed.

Also, is your extruder motor current set to 85% of rated max?

Firmware 2.05 is out now, so may want to upgrade to that regardless.

DIY-O-Sphere

Maybe the jerk value for the extruder is too high.
While setting up PA today, I had the same issue. After decreasing jerk to 1000 mm/min I was able to print the test cube.

Samuel235

@Phaedrux - Do you want me to just make a normal print with no attempts of using PA and then do a M122 or would you prefer me to perform this after trying PA? I will perform both and post the findings from them over the next couple of days. I will use the same gcode file for both and just manually enable PA on one and not the other.

I will also try your suggestion of reducing the speed and max extruder speed after those two tests have been performed. I do believe that the steppers I have are rated for 2.1A, so 85% of that would be 1.785A. The extruder motor is currently set to use 1.4A. Is this something you would increase the power to?

@DIY-O-Sphere - I will give that a shot soon and feed back my findings.

Thank you to the two of you for taking the time to contribute to my troubleshooting!

Phaedrux

@Samuel235 Yes both with and without PA would help to establish a baseline.

I'd probably set the extruder motor current to 1.6 or 1.7 and see how it goes.

Samuel235

@Phaedrux - What printer would be a good test here, would just a simple cube be enough to test if its working or not, not looking to test how good its working, just that it is working...

Phaedrux

@Samuel235 A cube would probably be alright. A benchy makes for a good test since it has a range of move types and areas to highlight flaws.

Since the issue we are trying to highlight is likely involving retraction and pressure advance, a simple XYZ cube scaled up a bit would be a good choice. Slightly more complex than a 4 sided cube but not as complex as a benchy and still fast to print.

xyzCalibration_cube.stl

Samuel235

@Phaedrux - Thank you for including the .stl for me. I will get to that tonight or tomorrow morning (UK Based).

Samuel235

Morning all,

I can confirm that PA now seems to be working after a change of extruder motor current, I assume it was skipping steps due to this. I'm going to continue further today to calibrate PA but I have just ran a XYZ Cube at 150% size and got awesome results from it, with a PA value of 0.22. I have included the information below that I said I would gather.

I do see some hiccups @Phaedrux, but I have done a quick research through this forum and can see that its not really an issue unless you are seeing around 50 per 200mm, is that correct?

M572 before PA enabled:

M572
Extruder pressure advance 0.000

M122 before PA enabled:

M122
=== Diagnostics ===
RepRapFirmware for Duet 2 WiFi/Ethernet version 2.03 running on Duet WiFi 1.02 or later + DueX5
Board ID: 08DGM-956GU-DJMSN-6J1F4-3SJ6N-1BNBF
Used output buffers: 5 of 24 (20 max)
=== RTOS ===
Static ram: 25680
Dynamic ram: 94256 of which 308 recycled
Exception stack ram used: 596
Never used ram: 10232
Tasks: NETWORK(ready,524) HEAT(blocked,1236) DUEX(suspended,156) MAIN(running,1668) IDLE(ready,160)
Owned mutexes:
=== Platform ===
Last reset 22:11:00 ago, cause: power up
Last software reset at 2019-12-23 18:30, reason: User, spinning module GCodes, available RAM 10304 bytes (slot 1)
Software reset code 0x0003 HFSR 0x00000000 CFSR 0x00000000 ICSR 0x0441f000 BFAR 0xe000ed38 SP 0xffffffff Task 0x4e49414d
Error status: 16
Free file entries: 10
SD card 0 detected, interface speed: 20.0MBytes/sec
SD card longest block write time: 0.0ms, max retries 0
MCU temperature: min 48.9, current 52.3, max 55.6
Supply voltage: min 24.0, current 24.3, max 24.6, under voltage events: 0, over voltage events: 0, power good: yes
Driver 0: standstill, SG min/max 0/1023
Driver 1: standstill, SG min/max 0/1023
Driver 2: standstill, SG min/max not available
Driver 3: standstill, SG min/max 0/1023
Driver 4: standstill, SG min/max not available
Driver 5: standstill, SG min/max 8/252
Driver 6: standstill, SG min/max 34/260
Driver 7: standstill, SG min/max 31/250
Driver 8: standstill, SG min/max 0/266
Driver 9: standstill, SG min/max not available
Date/time: 2019-12-31 18:36:04
Cache data hit count 4294967295
Slowest loop: 113.77ms; fastest: 0.08ms
I2C nak errors 0, send timeouts 0, receive timeouts 0, finishTimeouts 0, resets 0
=== Move ===
Hiccups: 0, FreeDm: 169, MinFreeDm: 146, MaxWait: 0ms
Bed compensation in use: mesh, comp offset 0.000
=== DDARing ===
Scheduled moves: 0, completed moves: 0, StepErrors: 0, LaErrors: 0, Underruns: 0, 0
=== Heat ===
Bed heaters = 0 -1 -1 -1, chamberHeaters = -1 -1
Heater 0 is on, I-accum = 0.5
Heater 1 is on, I-accum = 0.5
=== GCodes ===
Segments left: 0
Stack records: 4 allocated, 0 in use
Movement lock held by null
http is idle in state(s) 0
telnet is idle in state(s) 0
file is idle in state(s) 0
serial is idle in state(s) 0
aux is idle in state(s) 0
daemon is idle in state(s) 0
queue is idle in state(s) 0
autopause is idle in state(s) 0
Code queue is empty.
=== Network ===
Slowest loop: 200.53ms; fastest: 0.08ms
Responder states: HTTP(0) HTTP(0) HTTP(0) HTTP(0) FTP(0) Telnet(0) Telnet(0)
HTTP sessions: 1 of 8
- WiFi -
Network state is running
WiFi module is connected to access point
Failed messages: pending 0, notready 0, noresp 1
WiFi firmware version 1.23
WiFi MAC address XXXXXXXX
WiFi Vcc 3.32, reset reason Turned on by main processor
WiFi flash size 4194304, free heap 24400
WiFi IP address XXXXXXXX
WiFi signal strength -55dBm, reconnections 0, sleep mode modem
Socket states: 0 0 0 0 0 0 0 0

M572 after PA enabled, value of 0.22:

M572
Extruder pressure advance: 0.220

M122 after PA enabled, value of 0.22:

M122
=== Diagnostics ===
RepRapFirmware for Duet 2 WiFi/Ethernet version 2.03 running on Duet WiFi 1.02 or later + DueX5
Board ID: 08DGM-956GU-DJMSN-6J1F4-3SJ6N-1BNBF
Used output buffers: 5 of 24 (20 max)
=== RTOS ===
Static ram: 25680
Dynamic ram: 94256 of which 308 recycled
Exception stack ram used: 492
Never used ram: 10336
Tasks: NETWORK(ready,524) HEAT(blocked,1236) DUEX(suspended,156) MAIN(running,1668) IDLE(ready,160)
Owned mutexes:
=== Platform ===
Last reset 06:31:07 ago, cause: software
Last software reset at 2019-12-31 18:44, reason: User, spinning module GCodes, available RAM 10232 bytes (slot 2)
Software reset code 0x0003 HFSR 0x00000000 CFSR 0x00000000 ICSR 0x0441f000 BFAR 0xe000ed38 SP 0xffffffff Task 0x4e49414d
Error status: 16
Free file entries: 10
SD card 0 detected, interface speed: 20.0MBytes/sec
SD card longest block write time: 0.0ms, max retries 0
MCU temperature: min 40.9, current 41.0, max 57.7
Supply voltage: min 23.9, current 24.5, max 24.6, under voltage events: 0, over voltage events: 0, power good: yes
Driver 0: standstill, SG min/max 0/1023
Driver 1: standstill, SG min/max 0/1023
Driver 2: standstill, SG min/max not available
Driver 3: standstill, SG min/max 0/1023
Driver 4: standstill, SG min/max not available
Driver 5: standstill, SG min/max 0/253
Driver 6: standstill, SG min/max 15/257
Driver 7: standstill, SG min/max 0/252
Driver 8: standstill, SG min/max 0/261
Driver 9: standstill, SG min/max not available
Date/time: 1970-01-01 00:00:00
Cache data hit count 4294967295
Slowest loop: 101.62ms; fastest: 0.08ms
I2C nak errors 0, send timeouts 0, receive timeouts 0, finishTimeouts 0, resets 0
=== Move ===
Hiccups: 129, FreeDm: 169, MinFreeDm: 146, MaxWait: 0ms
Bed compensation in use: mesh, comp offset 0.000
=== DDARing ===
Scheduled moves: 0, completed moves: 0, StepErrors: 0, LaErrors: 0, Underruns: 0, 0
=== Heat ===
Bed heaters = 0 -1 -1 -1, chamberHeaters = -1 -1
Heater 0 is on, I-accum = 0.0
Heater 1 is on, I-accum = 0.6
=== GCodes ===
Segments left: 0
Stack records: 4 allocated, 0 in use
Movement lock held by null
http is idle in state(s) 0
telnet is idle in state(s) 0
file is idle in state(s) 0
serial is idle in state(s) 0
aux is idle in state(s) 0
daemon is idle in state(s) 0
queue is idle in state(s) 0
autopause is idle in state(s) 0
Code queue is empty.
=== Network ===
Slowest loop: 200.37ms; fastest: 0.08ms
Responder states: HTTP(0) HTTP(0) HTTP(0) HTTP(0) FTP(0) Telnet(0) Telnet(0)
HTTP sessions: 1 of 8
- WiFi -
Network state is running
WiFi module is connected to access point
Failed messages: pending 0, notready 0, noresp 7
WiFi firmware version 1.23
WiFi MAC address XXXXXXXX
WiFi Vcc 3.33, reset reason Turned on by main processor
WiFi flash size 4194304, free heap 24400
WiFi IP address XXXXXXXX
WiFi signal strength -55dBm, reconnections 0, sleep mode modem
Socket states: 0 0 0 0 0 0 0 0

Thanks,
Sam.

zapta

@Samuel235 said in Pressure Advance seems to not be working.:

got awesome results from it, with a PA value of 0.22

Is this a direct extruder or bowden?

Samuel235

@zapta Its bowden, around 650mm bowden length.

Phaedrux

@Samuel235 said in Pressure Advance seems to not be working.:

Hiccups: 129

I wouldn't be too concerned by this over the course of a print.

Do you happen to have Z hop on retract enabled?

You can do more fine grained testing to try and pin down when the hiccups are occuring. Every time you send M122 it resets the counter, so you can send it at the start, send it after homing, send it after the first layer, etc. and eventually you'll get an idea of where and when they are occuring.

Samuel235

@Phaedrux - I was doing this while it was printing also, it seems to be consistent on most layers if i remember correctly. I'm not currently running Z Hop, no.

zapta

@Samuel235 said in Pressure Advance seems to not be working.:

@zapta Its bowden, around 650mm bowden length.

0.22 for a 650mm bowden is very low, good for you. I got > 1.0 with 600mm 1.9mm capricon bowden and lowered it to 0.15 when switched to direct drive.

Samuel235

I'm currently running some tests to attempt to calibrate it. I'm currently using CURA so I'm unable to force a seam to be in the middle of a flat face, so i'm using a cone print to put a seam on the face and to change PA as the print goes and then to find the best section. I'd be interested to know the calibration method you all face, do you all go for the python script that is floating around?

Phaedrux

@Samuel235 said in Pressure Advance seems to not be working.:

I'm currently using CURA so I'm unable to force a seam to be in the middle of a flat face

It can be done in Cura.
https://ultimaker.com/en/resources/52343-shell

The options may be hidden by default. Use the gear icon on the shell heading to see any hidden options.

Z seam alignment - User specified
Z seam position - back
Seam corner preference - none

Produces the desired result. That's in 4.4.1. In older versions there was an X and Y position you could specify. The setting is still there in the settings visibility filter, but it's not being shown and I'm not sure what's blocking it. Regardless, setting it to back, front, left, or right works to align it to a face.

Samuel235

@Phaedrux - Im on 4.2.1 and the XY position will not put it in the middle of a flat face for me and a few others I chat to. I will try their update shortly to see if that new option works for me.

Phaedrux

@Samuel235 The corner preference must be none as well.

Samuel235

I have just updated my Cura, and still facing the same issues:

Will attempt to find a work around later today using another slicer.

burtoogle

Re getting the z-seam in the middle of a flat face using Cura. Well, it can't be done using the UM releases but my Cura builds do now provide that capability. Setting the z-seam to user-defined and seam corner preference to none will enable this feature. You can find my releases at https://www.dropbox.com/sh/s43vqzmi4d2bqe2/AAADdYdSu9iwcKa0Knqgurm4a?dl=0. Please read the README.md file there for more info.

Here's an example, you can see the travel moves associated with the z-seam to the left of the middle of the flat area at the botttom of the image.

Phaedrux

@burtoogle said in Pressure Advance seems to not be working.:

Well, it can't be done using the UM releases but my Cura builds do now provide that capability.

Just one more reason to use your builds.

@Samuel235 I was going by memory on the settings and didn't realize that the stock Cura does not allow this.