Some walls are at full speed during initial layer. Is this a bug?

[JRon 1]

Hi. I am using version 5.5 and my max print speed is 150 mm/s but i want my initial speed to be around only between 40 to 50 mm/s. My problem is when i slice, some of the walls at the initial layer are at full speed (150mm/s) and it causes them not to stick. Some of them with proper initial speed are sticking just fine. In a single part print, some models have a correct 50 mm/s initial wall speed and some do not. In multiple part prints, it always happen. The rest have correct values but there is 1 or 2 parts that are at full speed. Could you help me with this guys? My current soultion is to open the gcode and edit the speed of the initial walls at first layer and it si time consuming specially for complex models. I would really appreciate any help guys. Thank you.

[Slashee_the_Cow 268]

Could you please post a copy of a gcode file before and after you edit it, and if possible, a Cura project file (.3mf, in Cura go to File > Save Project). Also, what printer do you use? I know some Creality printers have ignored speed and acceleration limits written into the gcode (whether it's a bug or they want to impress people with fast prints I don't know).

[wus 0]

I have the same Problem on linux. Here some of my system information for the developers:

 

wus@workshop3:~ $ lsb_release -a
No LSB modules are available.
Distributor ID: Debian
Description:    Debian GNU/Linux 11 (bullseye)
Release:        11
Codename:       bullseye
wus@workshop3:~ $ uname -a
Linux workshop3 5.10.0-26-amd64 #1 SMP Debian 5.10.197-1 (2023-09-29) x86_64 GNU/Linux
wus@workshop3:~ $ /lib/x86_64-linux-gnu/libc.so.6 --version
GNU C Library (Debian GLIBC 2.31-13+deb11u7) stable release version 2.31.
Copyright (C) 2020 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.
There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE.
Compiled by GNU CC version 10.2.1 20210110.
libc ABIs: UNIQUE IFUNC ABSOLUTE
For bug reporting instructions, please see:
<http://www.debian.org/Bugs/>.
wus@workshop3:~ $ ls -la /opt/UltiMaker-Cura-5.5.0-linux-X64.AppImage 
-rwxr-xr-x 1 wus wus 303776960 Nov 13 04:50 /opt/UltiMaker-Cura-5.5.0-linux-X64.AppImage

 

Plugins installed:

 

How to reproduce the problem:

 

1. Use standard "Generic PLA"
2. Use Standard "Creality Ender 5" Printer
3. use Standard 0.2 profile with only temp and speed changes (see screenshot)
4. Use this test STL File: https://www.klipper3d.org/prints/ringing_tower.stl
5. Slice

 

The inner wall speed on layer 1 is 145 mm/s, it should be 20mm/s as the rest of the initial layer (See screenshot), this is the result: CE5_ringing_tower.gcode

 

 

Downgrading to Cura 4.4.0 solves the problem. Seems to have been introduced in the latest release.

 

Thanks for having a look at it and kind regards

-S

 

 

 

Edited November 14, 2023 by wus
added plugin information.

[Slashee_the_Cow 268]

@wus your last screenshot doesn't actually show the initial layer speed setting, you need to scroll further down. And it would really help to have a .3mf created by you which will include all the settings specific to your slice. The default quality presets and material settings can be modified by the user so there is absolutely no guarantee that if I followed your steps, the slice would end up being the same.

[Slashee_the_Cow 268]

4 hours ago, wus said:

The inner wall speed on layer 1 is 145 mm/s

I'm going to assume that's a typo. It's 125mm/s.

 

In my experiments I've found that out of the 20 or so models I tested (both my own and ones from other people), only the model other than your ringing tower example that shows this problem is https://www.thingiverse.com/thing:2221374/files.

 

 

I've also found that the problem is likely something in the print settings, but I'm not sure what. I select one of my custom presets (which I use for my E3V3SE) for the Ender-5 and the print speed for the bottom layer goes down to what you'd expect. I might have to do a process of elimination at some point when it isn't midnight.

[Slashee_the_Cow 268]

Okay, I have no clue why this works, but it seems to work:

 

Turn on Walls > Print Thin Walls

 

No clue why this works. Could be a rounding error in the calculations somewhere.

[GregValiant 1,254]

I've been printing smaller things lately and I had not noticed this.  With all Print and Travel speeds at 75 in Cura I'm getting speeds excess of 150 in the gcode.  That is simply too fast and the quality of the print suffers.

 

It looks to me like "Speed / Flow Equalization Ratio" is the culprit.  With it turned down to 0% everything is fine.

I just checked another model with the equalization at 100% and the printing speed is up to 194.81mm/sec.  My recollection is that 5.4 didn't have that effect.

The print speed here should be F4500 (75mm/sec).

G1 F4522.6 X129.811 Y148.87 E3395.59444
G1 F6000 X129.461 Y149.16 E3395.60577
G1 F8955.2 X126.129 Y152.907 E3395.68958
G1 F9090.9 X125.401 Y153.667 E3395.7069
G1 F9137.1 X124.534 Y154.448 E3395.72602
G1 F9183.7 X123.673 Y155.11 E3395.74372

 

With Flow Equalization at 0% these are approximately the same place on the model.  This is what I've seen previously.

G1 X113.139 Y114.071 E3465.42412
G1 F2100 E3459.42412
G0 F4500 X112.824 Y122.97
G0 X108.616 Y135.154
G0 X100.788 Y145.825

 

On another model the print speeds were pushed to over 190.  On that same model with the identical setup 5.4.0 showed a max speed of 104.

 

C'Mon man, if I wanted to print at 190 I'd would have bought a different printer.  And those speeds are showing up though I have "Maximum Speed X" and "Maximum Speed Y" set to 100 in Cura.

 

So what's up with this @nallath.  We're all on the Autobahn?

 

 

 

 

 

Edited November 14, 2023 by GregValiant

[manumatic 0]

Howdy. I am also having the same issue. reverting back to 5.4 solves my issue. here are 2 files, one 5.5, and the other 5.4, saved in 3mf. There are a few minor setting changes, but the initial layer is the same.

5 4 test file.3mf 5 5 test file.3mf

[Slashee_the_Cow 268]

1 hour ago, manumatic said:

Howdy. I am also having the same issue. reverting back to 5.4 solves my issue. here are 2 files, one 5.5, and the other 5.4, saved in 3mf. There are a few minor setting changes, but the initial layer is the same.

5 4 test file.3mf 24.63 kB · 0 downloads 5 5 test file.3mf 24.63 kB · 1 download

Your 3mf files only contain models, not Cura projects, so they don't have your settings. In Cura you need to load the model, set it up like you're about to print, then go to File > Save Project and upload the 3mf file from that.

[manumatic 0]

23 hours ago, Slashee_the_Cow said:

Your 3mf files only contain models, not Cura projects, so they don't have your settings. In Cura you need to load the model, set it up like you're about to print, then go to File > Save Project and upload the 3mf file from that.

and so i attempt again. lol. saved as directed.

5 4 test file.3mf 5 5 test file.3mf

[Slashee_the_Cow 268]

I just had a look at both of those in 5.4, 5.5 and 5.6.0 beta 1. In all of them, for both files, the bottom layer was printing slowly at the initial layer speed. In your one from 5.5 it has Number of Slower Layers set to 2, so the second layer is also slow (but not as slow).

 

It's also worth noting that the calibration cube seems to deliberately start slow and then ramp up its speed towards the top - possibly to try and see if it adds any ringing.

 

To do any more investigative work I'd probably need the gcode files (one each from 5.4 and 5.5) generated from your end - since on my end they'll both look fine when it comes to bottom layer speed.

[DivingDuck 104]

On 11/14/2023 at 4:44 PM, GregValiant said:

It looks to me like "Speed / Flow Equalization Ratio" is the culprit.  With it turned down to 0% everything is fine.

I just checked another model with the equalization at 100% and the printing speed is up to 194.81mm/sec.  My recollection is that 5.4 didn't have that effect.

 

Thanks for pointing to this. I was a already so frustrated about the behavior of 5.5 so that I use more often alternative slicers these days. Frustration level, needed time to dial in Cura for each print and printed scrap was increasing too much.

 

After reading your comment I did some tests and it looks like you nail down one issue for my frustration with Cura.

 

Edited November 20, 2023 by DivingDuck

[Onack 0]

I have also the same problem and it is only for some models. Attached model (it is this one https://www.thingiverse.com/thing:723403) does have the problem if that helps debugging.

Snowman__Cookie_Cutter.STL

[GregValiant 1,254]

With the Snowman model I'm getting these speeds in 5.6.0.

(The print speeds are 75 and travel speed is 150 in Cura.)

 

;Slower Initial Layers: 2
;Extruder 1 (T0)
;  Flow Equalization Ratio: 100.0%
;The speed ranges for this print:
;  Maximum Travel Speed: 150 mm/sec
;  Minimum Travel Speed: 150 mm/sec
;  Maximum Extrusion Speed: 111.9 mm/sec
;  Minimum Extrusion Speed: 15.0 mm/sec

 

The only change to this slice was the Flow Equalization Ratio

;Slower Initial Layers: 2
;Flow Equalization Ratio: 0.0%
; The speed ranges for this print:
;Maximum Travel Speed: 150 mm/sec
;Minimum Travel Speed: 150 mm/sec
;Maximum Extrusion Speed: 75.0 mm/sec
;Minimum Extrusion Speed: 25.0 mm/sec

 

This seems to be affected by the line widths that are required by a specific model.  The "snowman" doesn't show anywhere near the "compensation" exhibited by whatever model I used up above.

 

 

[DBMandrake 1]

Same problem here with Cura 5.5.0. Overall print speed is set to 200mm/s, initial layer print speed is set to 35mm/s in the profile however some of the lines in the first layer are printing at well over 100mm/s and as a result are not sticking to the bed, with the filament being dragged across the bed causing corner cuts and blobbing.

 

It can be seen in the print speed view as well, below:

 

 

The blue lines are at the correct speed, the green lines are much much faster, to the eye when printing it looks like maybe 100mm/sec or so.

 

I am going to try updating to 5.6.0, if that doesn't help reverting to 5.4.0 as I see someone in the thread reports they don't have this issue in 5.4.0 and I only fairly recently went from 5.4.0 to 5.5.0 myself.

SSPK_christmas.3mf

Edited December 22, 2023 by DBMandrake

[Slashee_the_Cow 268]

17 minutes ago, DBMandrake said:

The blue lines are at the correct speed, the green lines are much much faster, to the eye when printing it looks like maybe 100mm/sec or so.

I'm feeling pedantic. Let's look at that gradient:

Did you try altering the flow equalisation ratio and maybe line width like Greg suggested above?

[DBMandrake 1]

Ok I tried updating to 5.6.0 - no improvement.

 

I then migrated my 5.5.0 configurations and profiles manually back into my 5.4.0 installation which was still there, and the problem is resolved:

 

 

First layer line speeds are all blue so around 35mm/sec, using the exact same profiles and overrides. This definitely seems to be a bug or change introduced in 5.5.0 and would explain some difficulties I've had recently with prints with fine details on the first layer - some of the first layer lines are being printed as much as 3 to 4 times too fast.

 

I've attached the 3mf file exported from Cura 5.4.0 below, hopefully someone can compare this to the previous 3mf file exported from 5.5.0 to help figure out this problem as it looks like I'll be staying on 5.4.0 for now.

SSPK_christmas-5.4.0.3mf

[DBMandrake 1]

14 minutes ago, Slashee_the_Cow said:

I'm feeling pedantic. Let's look at that gradient:

Did you try altering the flow equalisation ratio and maybe line width like Greg suggested above?

 

You're assuming that gradient is linear - with nothing to say one way or the other I would not make that assumption. Watching the printer print it is a lot faster than 67mm/sec I can say.

 

No, I have not changed flow equalisation ratio - I've reverted to 5.4.0 using identical profiles and overrides and the problem is resolved. Flow equalisation ratio is set to the default of 100% in both cases.

 

Edit: Forgot to note - I'm printing using Klipper, and Klipperscreen dynamically reports the movement speed was around 80-120mm/sec during extrusion of the first layer lines indicated in green which should have been extruded at no more than 35mm/sec according to settings in the profile. I can't see how this is anything other than a bug where the initial layer speed settings in the profile are not being honoured.

Edited December 22, 2023 by DBMandrake

[GregValiant 1,254]

This has been noted in a few bug reports on Github (including my own).  I don't think there has been an official response to any of them, but they are there.

 

In 5.6 - dropping the Flow Equalization to 0% fixes the problem.  The setting worked differently in 5.4.  As I recall it would slow the speed for heavy flow lines (like printing the infill at 2X layer height) but didn't jack the speed up on narrow line widths.  That was the change and so it's likely a "design intent" rather than a "something is broken" bug.  I don't care for it myself and turning off the equalization completely isn't a good option for me because I do tend to print infill thicker to speed things up.

[DBMandrake 1]

8 minutes ago, GregValiant said:

This has been noted in a few bug reports on Github (including my own).  I don't think there has been an official response to any of them, but they are there.

 

In 5.6 - dropping the Flow Equalization to 0% fixes the problem.  The setting worked differently in 5.4.  As I recall it would slow the speed for heavy flow lines (like printing the infill at 2X layer height) but didn't jack the speed up on narrow line widths.  That was the change and so it's likely a "design intent" rather than a "something is broken" bug.  I don't care for it myself and turning off the equalization completely isn't a good option for me because I do tend to print infill thicker to speed things up.

 

Thanks for explaining what's happening. Personally I would still class it as a bug - why have profile settings to set the 1st layer speeds (which should be maximum speeds) if they are just going to be ignored by another setting and be greatly exceeded ? Anyone trying to troubleshoot this issue is going to look at their first layer speeds being set to for example 35 but see the printer is printing at more than twice that speed and consider it to be a bug.

 

Like you I don't like the sound of the compromise of disabling flow equalisation so I'm probably just going to stay with 5.4 for now until I hear something more about this issue. Maybe I'll check back in another couple of versions to see if the issue is still there...

 

Edited December 22, 2023 by DBMandrake

[GregValiant 1,254]

I pulled some speed numbers out of a file made with 5.6.

File size:    217,167 lines

Print speed:   75

Only looking at the speed of extrusions:

Instances of speeds over 75:   2,586

Average of the speeds over 75:   97.55

High speed:  155.44

 

So of that particular file about 1.19% were overspeed, but some were indeed double speed.  There were no over-speed lines in the first layer.  That likely has something to do with the model geometry.

 

If I get truly, really, absolutely, mind-numbingly, bored then I'll chart the lengths of the extrusions involved.  The end of that particular model is a hemisphere so there will be lots of short line segments.

Here you can see that the fast lines are the narrow lines.  It's certainly compensating, but in my (never humble) opinion, it's a bit much.  These are straight shots here so the print head can and will hit 155 in the straightaways.

 

This is "Speed Changes of Extrusions".  It only charts the lines were a speed is mentioned, and not the intervening extrusions made at that speed.  The chart should really be a lot longer, but the spikes and dips are variations from "75m/sec" which is the flat horizontal line.

 

This is my "Sportfisherman" Benchy

Edited December 23, 2023 by GregValiant

[DFAB 0]

On 12/22/2023 at 5:18 PM, DBMandrake said:

 

Thanks for explaining what's happening. Personally I would still class it as a bug - why have profile settings to set the 1st layer speeds (which should be maximum speeds) if they are just going to be ignored by another setting and be greatly exceeded ? Anyone trying to troubleshoot this issue is going to look at their first layer speeds being set to for example 35 but see the printer is printing at more than twice that speed and consider it to be a bug.

 

Like you I don't like the sound of the compromise of disabling flow equalisation so I'm probably just going to stay with 5.4 for now until I hear something more about this issue. Maybe I'll check back in another couple of versions to see if the issue is still there...

 

 

+1 =>  I would still class it as a bug too. 

 

I have the same issue with 5.6 version.  

I don't like the idea to disable the "flow equalization ratio" 

Then, I'll go back to v5.4

 

[AGMeadows 0]

This issue just popped up for me today. I was printing one model and it worked fine. Then when I moved it around it was no longer fine. The first later walls were at full speed and had no chance of sticking.

 

My solution was to create a new profile using the default Draft settings and changing it to match my old profile. There must be a problem moving the old profiles to 5.5+.

[gustavofn 1]

I have the same issue with Cura 5.6 and Elegoo Neptune 5.6.0. Looks like the first inner wall is being printed at full speed and not limited to the first layer initial speed, that causes the filament to not attach to the bed correctly.

[Tikka667 0]

On 12/29/2023 at 4:48 PM, AGMeadows said:

This issue just popped up for me today. I was printing one model and it worked fine. Then when I moved it around it was no longer fine. The first later walls were at full speed and had no chance of sticking.

 

My solution was to create a new profile using the default Draft settings and changing it to match my old profile. There must be a problem moving the old profiles to 5.5+.

I’m having the same issue. The difference is, I created this profile on 5.6. I recently got the Ender 3 V3 KE, set everything up from scratch as there wasn’t a stock KE profile at the time. Changing the flow equalization isn’t working for me and would prefer not to in the first place. This is not the case with all models but a few of the smaller items are a problem. Anyone else find a solution for this? Will I have issues going back to an older version considering I started this profile on 5.6? Any help would be appreciated 🙂