Core-1 under extruded if Core-2 is used in the same layer

[gr5 2,172]

Maybe I should just print your file on my printer instead.

 

Look to see if the "bad" layers have different temperature than the good layers.  Or if the bad layers have a temperature that oscillates every other layer.

 

[gr5 2,172]

I just printed it. Wow.  Yeah mine does it also.  Okay so...

[gr5 2,172]

So at first I was like - "wow that's smaller than I expected" and also "Nope - looks fine - my machine doesn't do this".

 

Also by the way I rarely use PVA lately (I like breakaway) and it's been about a year since I used it and my PVA got "wet" despite being in a sealed bag with lots of dessicant.  It needs to be dried but that doesn't matter because the PVA isn't the issue.  By the way you set "support horizontal expansion" to zero.  It defaults to 3 for a good reason - this brings the support down to the print bed and makes it MUCH less likely to fail.  but your print didn't fail so whatever.

 

As you can see it recovered.

 

So then I took a more careful picture (and looked with some magnifying glasses) and I could see - my printer does indeed do it.  Also I noticed that on the upper layers it was 3 seconds per layer per tower.  3 seconds!!!!  This is important.

 

Anyway so my printer does do it as you can see:

 

 

I'm not sure if it is as bad as yours or about the same??

 

Anyway - it could be partly Z axis but I think it's temperature.  At 3 seconds - that's not really enough for the print head to come all the way back to the eariler temperature and as it does the second layer (it does 2 in a row in the PVA section) it's now warmer - it has had 3 more seconds to heat up.  So that's what I think it is.

 

To prove it do a 30mm cube (instead of 10mm) and make sure there is at least 30% infill to let the nozzle heat up to proper temperature before printing the outer walls.

 

ALSO - I didn't realize how subtle the issue is!  I can't even see it without reading glasses.  Plus I have to twist it in the light just so (which everyone naturally does when inspecting something but if no one is really looking for defects they are unlikely to notice this).

 

[gr5 2,172]

The authors of this feature (cool one head while the other prints) did it for good reason and they assumed the part was a bit bigger and it would stabilize on temperature while printing the infill.  It's okay if the infill is slightly under or over extruded so you print that first.  They didn't count on your infill taking about 1 second!  Lol.  Just not enough time for things to stabilize.

 

Cura does all manner of speedups related to the nozzle temperature.  When it is getting to the end of a layer and about to go print the pva it starts the cooling something like 6 seconds early so that the nozzle won't leak as much.  When it is finishing up the pva it starts heating the pla nozzle something like 15 seconds before it is needed.  Then at the actual moment of switching there is a wider temperature tolerance - it can be something like 3 degrees to cold.

 

Something in all that is not working - they weren't expecting 3 seconds to print one tower's layer!  So it's doing the cooldown later than it's supposed to (as the PVA layer doesn't take 15 seconds - it takes 3 plus maybe another 3 to switch nozzles) and heating up too late as well (although it should pause the printer if the nozzle is significantly too cool).  Anyway this all doesn't work so well when the layers are less than 15 seconds to print.

 

So there is a PID controller that controls the power to the nozzle heater based on requested temperature.  There are 3 values: one for each P, I, D (proportional, Integrated, Differential).  You can actually play with these values for an individual core.  The values can be stored in the core.  Ultimaker does not do this - they set it the same for all AA 0.4 cores.  but if you get a heater that is a few watts higher or lower then the PID could be slightly out (versus mine which exhibited similar issues).

 

Anyway the point is not necessarily every core is the same but most should be very close.

 

For example the 3dsolex cores have different PID values than Ultimaker cores because they have much larger heaters (I think they are 35 Watts?  Versus something like 25 Watts?  I forget).  So the PID values are stored right on the eeprom chip on the cores for 3dsolex cores.

 

[gr5 2,172]

I thought of another potential test!  Set these all to 200C.  Leave the 60's alone but set the 190,185, and 100 to all be 200C that way it shouldn't cool down when printing the PVA.

 

The downside is you get some leakage.  Hmm.  If you get leakage that CAN ALSO cause the next layer to be underextruded.  No that's a bad test.  A better test is to print something with more infill - like 10 seconds worth - so the nozzle gets to equilibrium before printing the outer shells.

 

OH ONE MORE THING - there are 2 parameters that you didn't touch:

outer before inner walls

infill before walls

both are unchecked so it does inner wall, outer wall, then infill.  So amount of infill doesn't matter much.  So the advantage of the 30mm cube is you have more inner walls to print to get up to the right temperature and pressure.  This is advisable because if you print infill first you can (just barely) sometimes see it on the outer walls.  But still you could try printing infill first and do more infill.  As an experiment.  To prove it has nothing to do with the Z axis.

 

I would just try printing a 30mm cube.  20% infill is plenty (to support the top skin).

 

[JD-Art 1]

okay that was a lot of posted i'll see if i can get all the comments correct 😉

 

19 hours ago, gr5 said:

By the way you set "support horizontal expansion" to zero.  It defaults to 3 for a good reason - this brings the support down to the print bed and makes it MUCH less likely to fail.  but your print didn't fail so whatever.

 

I know about the support expansion and most the times i also print with it. but for this test it was turned off/ set to 0.

if left on, the problem would have been all the way to the bottom on the tower like on the T-test print i did from GregValiant.

 

 

20 hours ago, gr5 said:

I'm not sure if it is as bad as yours or about the same??

 

ALSO - I didn't realize how subtle the issue is!  I can't even see it without reading glasses.  Plus I have to twist it in the light just so (which everyone naturally does when inspecting something but if no one is really looking for defects they are unlikely to notice this).

 

Min is worse! I can see it without glasses 😉 and also feel it by totch.

 

But the fact that you also have it more or less, gives me hop that it can be overcome with settings and not a bigger problem with the printer it self.

 

What bothers me the most, is that the problem haven't always been there, I have in the past printet smaller items with PVA support that ditten have it.

 

20 hours ago, gr5 said:

A better test is to print something with more infill - like 10 seconds worth - so the nozzle gets to equilibrium before printing the outer shells.

 

I'll do a 30x30 cube tomorrow, printer is occupied.

 

20 hours ago, gr5 said:

OH ONE MORE THING - there are 2 parameters that you didn't touch:

outer before inner walls

infill before walls

both are unchecked so it does inner wall, outer wall, then infill.  So amount of infill doesn't matter much.  So the advantage of the 30mm cube is you have more inner walls to print to get up to the right temperature and pressure.  This is advisable because if you print infill first you can (just barely) sometimes see it on the outer walls.  But still you could try printing infill first and do more infill.  As an experiment.  To prove it has nothing to do with the Z axis.

 

I used the default settings to be sure that it wasn't something in my profile conflicting. but yes in hindsight i should have been more ops. on this. because you statement is pretty validated

 

I just didn't give it so much thought because I have made prints that were 130x180mm that had the exact same problem

(no its not a masive shape but the layer time is much more then 15sek)

 

The item was printet with PLA support with PVA support Interface and again where the PLA is in layers with PVA the effect is the same.

 

 

 

 

 

 

 

[JD-Art 1]

 

Well. I did the 30x30 cube, set infill and inner wall to print before the outer. and the problem is still there 😞

it is more or less the same amount of displacement as on the 10x10 cube, maybe even a bit worse O.o

 

 

Theres nothing wrong with the Brim, I was just a bit irritated when removing it from the build plate.

Edited April 29, 2022 by JD-Art

[gr5 2,172]

Okay so it's not temperature.  It's not Z axis.

 

I think it's head play.  I think it's the bearing between the cores.  I have a test for you.

 

So I don't understand this but the problem happens when you do the core change for the right core.  There is more stress placed on the print head when changing cores.

 

There is a known problem with UM3, S3, S5 print heads with the bearing between the cores.  It is quite short.  There are 2 rods that pass through the print head.  The one that passes left/right goes through a bearing that is quite long - as long as the print head is wide.  However the other rod goes through a short bearing.  This bearing is held in place by the plastic of the print head.  The plastic can get old and crack and get a little loose.

 

The most common symptom is head backlash where the head rotates around the rod that travels left/right through the print head.  This shows up in complicated patterns where some layers jut out just like in your photo of the larger part.  If you print a layer clockwise versus counterclockwise or if you move the head inwards to print some detail, the head may be in a different angle/position and you get some layers that sitck inwards or outwards.  This was my very first theory but it didn't make sense for your part so I didn't mention it as I was looking at the pattern of printing (which corner was printed first, did it approach from the left or the right) and didn't think about the lift switch applying more force.

 

Also the pattern usually only appears on the sides facing the front and rear of your printer.  So I could be wrong about head play.

 

Grab the print head and twist it gently back and forth using a "roll" motion like the print head is an airplane and it wants to bank left and right.  This is quite stiff.  Now do a "pitch" motion where the airplane wants to pitch nose up and nose down.  This always moves slightly more but not enough to cause even tiny errors on your print.  Unless your bearing came loose.  I don't know how to describe how much is okay and how much is bad.

 

The fix is to open the head and put in a shim using paper or something.  Some brand new print heads already have the problem but most acquire the problem after months of printing.  I've been printing for years and my S5 and my UM3 are both fine.  A friend had the problem from the first day and he fixed it within the first week with a shim.

 

So here's my test.  Print just a single tower.  A 10mm wide tower (maybe 30mm tall).  After it has been printing for at least 2 mm, push the "lift switch" on the right side of the head so that the right core moves downwards.  As long as your tower is only 10mm wide and you are at least 2mm above the glass, the right core shouldn't hit anything.  Let it print 2 layers and then push the "lift switch" back again to raise the right core.  Let it print at least 2 layers.  Repeat this a few times.  See if you get the same issues.

 

However keep in mind that my S5 head play is pretty good and I get a similar pattern as you do and you think mine is not as bad but I am not convinced.

 

 

[gr5 2,172]

I'm not convinced it is head play as it should only show up on front/rear face of the part.  But it's worth testing.

 

It still looks like a Z issue.  It makes total sense that it is a Z issue.  If Z doesn't move enough you over extrude a little as there is less space to extrude into.  If Z then catches up it underextrudes a little because now there is more than the nominal 0.15mm of space to extrude into.  Z issues make sense!  Z play.  Z backlash.

 

In the PVA region the Z axis is approaching the new layer from opposite directions (it moves the bed down away from nozzle while changing cores so moves the bed up to the layer 2mm a moment before printing again.  Then when printing the next layer it just moves the bed down by 0.15mm to print the next layer.  This repeats approaching every other layer from above and below and I'd be surprised if it didn't have every other layer sticking out like that.  Yet you tried to add weights and it didn't help.  And I added 2 or 3 zhops to a tower gcode file and it didn't have the layers sticking out.  So strange.

 

[gr5 2,172]

Looking at my part again - the left side is the worst, then the front is slightly better, then the right side is definitely better and the back is definitely the best.  By far the rear side is the best.  Why?

 

It prints back first, then left, then front, then right.  What???

 

If this is a Z issue it should have equal issues on all 4 sides.  If this is a "play" issue it should be worse on two opposite sides.  If it's an underextrusion or overextrusion issue related to the hot and cold ends only then it should get better or worse as you go in order (not best at the first line segment and worst at the second).

 

It could also be a speed change issue (partly) as it is printing the infill at a different speed than the outside.

 

SPEED ISSUES

 

Try setting all the speeds the same.  Search for "speed" and change the first 10 results to 35mm/sec.  Once you get to the "travel speed" leave the rest the same.

 

Other flow rate issues - line width

 

Also search for "line width" in the settings search box and change them all to 0.4mm and change the wall width (last setting I think if you search for line width) to 1.2mm so that it is a multiple of the line width.

 

Anyway do all that and look at the part using "flow rate" colors in PREVIEW mode and make sure it's all the same color and try printing again to see if your lines go away.  It will definitely change things as when it starts the outer shell it won't have a speed change which requires a change in nozzle pressure which takes a little while to equalize.

 

I have to say that Ultimaker gets these "genius" (not) ideas - they changed the line width on the S5 to be 0.35mm for a 0.4 nozzle because they found that on average nozzles tended to be a bit too small versus too large and also they tend to get buildup of caramelized filament inside the nozzle tip.  But in my experience, 0.4 works better than 0.35.  And they seem to agree now because they came out with the "engineering" profiles which use 0.4mm and parts are more dimensionally accurate.  But once you create a profile with lines at 0.35 you can never change it!  5 years later they will all tell you to use 0.4mm but they can't change the profiles because if you change a profile it will mess 10% of the people up and make their part different which will piss them off ("after 5 years you change the profile on us!  Now we have to redesign the part!  You just cost us millions of dollars in downtime!").  So they can't improve the old profiles and rarely (very rarely) come out with better profiles like the engineering profiles.  I'm glad it's not my job to create the profiles that can rarely ever be changed.  And can't incorporate new features that improve prints.

 

Before changing line width and speed:

 

After:

 

[JD-Art 1]

On 4/29/2022 at 2:54 PM, gr5 said:

Grab the print head and twist it gently back and forth using a "roll" motion like the print head is an airplane and it wants to bank left and right.  This is quite stiff.  Now do a "pitch" motion where the airplane wants to pitch nose up and nose down.  This always moves slightly more but not enough to cause even tiny errors on your print.  Unless your bearing came loose.  I don't know how to describe how much is okay and how much is bad.

 

I did the "airplane" test not 100% sure i did it right, but when doing as described i don't find anything to be off or unexpecting in the movement.

 

 

I found something weird, not sure if it's related. But, if I don't have support on, my print is according to Cure under extruding in the exact spot where the problem is. and when the support is active the flow is the same. on the physical model/test print it looks to be the opposite.

Another question why is the flow on my PVA alternating so much from layer to layer?

 

 

Test print with 0.4mm width and all speeds set to 35mm/sec

 

There's some other visual problems now, but the main problem it's actually much better. At first glance it looks okay.

But when looking at it with my reading glasses you can still see that the layers are going from wide to narrow like on the other test prints but it's much better.

 

Test print with only width set to 0.4mm speeds kept as standard settings.

 

When looking at Cura's flow analyses you can actually see that the affected mitter section of the right tower is variation in flow every other layer. if the layer counter at the right is correct it starts at 35, 37, 39.... till 65

 

So the speed is somehow affecting the flow of an entire layer every other layer. in a part that should not be different in speed or flow ??

 

 

 

 

 

[gr5 2,172]

1 hour ago, JD-Art said:

I found something weird, not sure if it's related. But, if I don't have support on, my print is according to Cure under extruding in the exact spot where the problem is

This is expected.  It's not underextruding - it's just printing slower.  Because of the setting minimum layer time.

 

Quote

So the speed is somehow affecting the flow of an entire layer every other layer. in a part that should not be different in speed or flow ??

 

What???????  That looks like the problem right there.  Let me try to duplicate.  By the way in cura you can show speed as well.  How come I don't see that in your earlier "red" photo?  Okay let me experiment...

[gr5 2,172]

I can't duplicate this every-other-layer-flow-change.  I tried messing with nozzle size and speed and using your original project and I can't duplicate this.

 

1) What version of Cura are you using?

2) Please post a project file (menu "save" "project file as") that shows this issue.

[JD-Art 1]

29 minutes ago, gr5 said:

I can't duplicate this every-other-layer-flow-change.  I tried messing with nozzle size and speed and using your original project and I can't duplicate this.

 

I made a mistake! (maybe that's a good thing here) for some reason Cura switched profile to "Normal" instead of "Visual" without me noticing it. So that's why you can't recreate it. If i try the settings in Visual it wont show the layer alternation.

 

But non the less here Cura shows how the Print actually looks.

 

29 minutes ago, gr5 said:

1) What version of Cura are you using?

2) Please post a project file (menu "save" "project file as") that shows this issue.

 

Cura 4.13

 

UMS5_PVA-test-020522.3mf

 

[gr5 2,172]

Okay so It's interesting that the speed thing made a difference.

 

So you didn't notice any difference in play between the rotations around the two axes through the print head?

 

Even on my printer there is a tiny bit difference.  It's noticable.  But I don't think it's a problem.

 

If you look at your prints that have the problem - is it equal on all 4 sides?  Do the sides that stick "out" continue or does an "out" side on one face turn into an "in" side when it goes around the corner?

[JD-Art 1]

13 hours ago, gr5 said:

So you didn't notice any difference in play between the rotations around the two axes through the print head?

 

Even on my printer there is a tiny bit difference.  It's noticable.  But I don't think it's a problem.

 

In general i would say no. But if I have to be really picky and need to find and error, then maybe theres some play in the front to back direction (the smallest axel)

 

 

13 hours ago, gr5 said:

If you look at your prints that have the problem - is it equal on all 4 sides?  Do the sides that stick "out" continue or does an "out" side on one face turn into an "in" side when it goes around the corner?

 

Yes, it's the same all way around. its like every other layer is eg. printer at 90% or something like that. or constantly under-extruding.

I am 100% sure its not layer shifting. (yes, bold claim)

It's not a perfect way to show it, but here you can see the front and the two sides. The layer with the "imperfection" is really uniform and consistent in the whole layer.

 

 

 

[gr5 2,172]

GREAT PHOTO!  

 

Each layer is supposed to move the bed down by 0.15mm.  If the bed instead moves down 0.1mm only then you will get 33% over extrusion.  If the bed catches up on the next layer and moves 0.2mm then you will get 25% underextrusion.  This is why I keep expecting it to be a Z issue.

 

The Z axis on the S5 appears to be 400 steps/mm.  Or 0.0025mm per step (actually .0025 per substep).  Due to "zebra stripe" issue I could imagine maybe an error of up to 3 steps or 0.0075 but that's about it.  That's still only 5% error maximum.  You are seeing more like 20% error. So I don't think it's a rounding issue (where it skips a step) or a weak servo driver (where it can have a step or two of play).

 

Because the pattern is the same all around I don't think it's backlash/play.

 

I don't think it's the gcode as I've looked at that through multiple viewers.  And flow color would be different on every other layer.

 

So that still leaves temperature or Z backlash.

 

Z backlash makes total sense - it approaches every other layer from the opposite direction.  What I don't understand is why it would be better with a larger cube or why we can't see it when I manualy some hops.  This is just such a good fit to the observations!  But doesn't fit all the data.

 

Temperature - well this makes a lot of sense - you get better/more flow when the nozzle is hotter.  What's happening is at colder temperatures there is more pressure in the nozzle so the feeder works harder and the stepper doesn't lose steps but the metal wheel that grips the filament slips a bit more so it extrudes less.

 

But it still has the problem even when you printed a larger cube that has more time to adjust.

 

FAN

 

So the fan goes to 50% power on the PVA layers.  While it's printing PVA it is cooling both nearby towers.  One of the towers might be directly below the fan hole.  Maybe the "tower" shrinks more when the fan is on higher power?  I don't know this doesn't make much sense but when the bed is close to the nozzle the air bounces off the bed and back to the nozzles and can cool the nozzles a bit.

 

Try setting the fan to be always either 100% or always 50%.  There are two tabs (1 and 2) for the left and right cores.  Make the fan speeds the same.

 

My printer may be unusual but there is no difference in fan speed at 50% versus 100%.  You have to get down to around 30% where you start to hear a difference in fan speed.  I usually print with 100% or 10%.  But my printer is probably unusual regarding the fan as I got an early "beta" S5.

 

[gr5 2,172]

Actually changing the fan speed might not help - it may have more to do with the position of the towers.  So also try putting the two towers farther apart - more than the width of the print head - try 100mm separation of the two towers and also make the fan at 50% for both materials.

[JD-Art 1]

 

16 hours ago, gr5 said:

Actually changing the fan speed might not help - it may have more to do with the position of the towers.  So also try putting the two towers farther apart - more than the width of the print head - try 100mm separation of the two towers and also make the fan at 50% for both materials.

 

 

It don't get much further than this 😉

 

 

 

Same result no difference in appearance vs. if they are printer next to each other..

I forgot to set the fan speed. i'll do that print tomorrow.

 

 

 

Just to try something new, this is a test with "Minimum layer time" set to 20s

 

Not quite sure what i expected, but not this. It's really bad printed just because of the longer layer time ?

but now the layer alternation is all the way "as also shown in the flow diagram" though still more dominant at the middle part.

 

[gr5 2,172]

Yeah I'm stumped.  I don't know what is causing the issue.  I guess fan is the last thing to try.

 

It's interesting that I saw something similar but each side shows a different amount (4 different amounts).

[JD-Art 1]

 

This just came off the printer this morning. it's not a big part, but definitely not a small one either.

And it has the same problem. Every layer that there is PVA in is under extruding in some way. "correction, every second layer is under extruding"

 

The only part that's fine is the 6mm at the top where there's no PVA in the layers.

 

 

Fan at 50% all the way: didn't make much difference. The print is a bit more "bloated" in lack of a better word.

"The bottom part looks worse on the picture then it is"

 

 

To test the theory about the steepers i did a print with a layer height of 0.31

 

Its the same behavior just bigger.

 

 

But interestingly this time while it was printing it was possible to see that it's the second layer that's printing smaller than the rest. So the order is PVA, PVA, PLA PLA and it's the last PLA layer before the nozzle switch that prints smaller.

 

So that means that it can't be the Z-axes because then it should have been the first layer right after the switch and not the last. Or maybe it can, I am not sure about this any more, but my logic still think that it should be the first layer after the switch (big moment on the z) and not the last as that layer is a normal increase/steep. And if it is the z-axes why don't it show on the other tests.

 

And i guess it can't be a nozzle warming up either, then it also should have been the first PLA layer and not the last Right??

 

It seems that the problem starts when the printer is dobbelt printing layers. eg. at the bottom without the PVA its (T=Towere) T1, T2, T1, T2 and so on, which is fine and at the PVA layers its T1, T1 and T2, T2 which prints bad.

 

Is it possible to force Cura to print all layers one at a time, so that it doesn't dobbelt print when using PVA, just for a test!

 

 

[gr5 2,172]

When you set a new goal temperature for the nozzle it often overshoots that goal so it's hard to say if the nozzle would be a bit warmer or cooler.  The change is too dramatic I think to be temperature.  Changing things like the distance between parts or the size of the part would make a big difference.

 

With the z "hop" of going over to change cores, the bed moves down for that and when it returns to start printing the first PLA layer the bed is moving back up and usually you would expect it to not move far enough so you would get a bigger gap and an underextruded layer.  Then the second layer the bed moves down and if it again doesn't move far enough you would get an overextruded layer.

 

All types of Z issues has the bed not moving far enough when changing directions.

 

Did you save any of the ufp files (or gcode files) where you have photos of the problem?  I'd like to double check filament flow using a 3rd party method like gcode.ws or gcodeanalyser.com.

 

[gr5 2,172]

So on your new print the lines seem more random.  This is typical of a dirty Z screw.  Since you are only using 2cm of the screw you could just clean the very top.  For a quick test I use a tissue (toilet or nose).  I stick it into the threads of the Z screw with my fingernail while someone else moves the Z up and down repeatedly.  I repeat this at least 10 times because the Z screw is triple helix.  3 helixes.  You have to get your fingernail (or a toothpick) into each of the 3 grooves.

 

This takes all of 2 minutes.

 

If it improves things even a little then it's probably worth it to remove the Z screw and clean it with WD40 over a newspaper.  I have never done this for an S5 but have done this for a UM2.  There are dangerous voltages inside the S5 so you have to power it off and remove the bottom cover and unplug the Z stepper motor.  I believe there are 4 screws holding the Z stepper in place and I believe once you remove those 4 screws and unplug the cable you can pull out the stepper and the Z screw all together out through the bottom of the printer.  It helps to have the bed in the up position before you start (put the printer on it's side and then on the printer raise the bed and then just cut power) (the printer works fine on it's side or upside-down).

 

After a complete cleaning add only one drop of grease.  If you only clean 5cm of the z screw you don't need to add any grease.

[JD-Art 1]

18 hours ago, gr5 said:

If it improves things even a little then it's probably worth it to remove the Z screw and clean it with WD40 over a newspaper. 

 

I didn't remove the z-screw, but put a towel behind it and brushed it in WD40 with a stiff pencil until all the grease was gone.

In my opinion it worked pretty well, and as i see it the z-screw is now clean, clean!! 🙂

 

18 hours ago, gr5 said:

Did you save any of the ufp files (or gcode files) where you have photos of the problem?  I'd like to double check filament flow using a 3rd party method like gcode.ws or gcodeanalyser.com.

 

This is the gcode for the pictures below.

 

 

UMS5_Tower.3mf

UMS5_Tower.gcode

This is printed after the z-screw cleaning! didn't make a difference.

 

 

UMS5_Raspi7inch_Case_SD_Access.3mf

UMS5_Raspi7inch_Case_SD_Access.gcode

 

 

 

 

 

[gr5 2,172]

I noticed something new.  But first...  I ran it through 2 gcode analyzers and the amount of extrusions is perfect.  Spot on.  No issues.  For example at this website gcode.ws I displayed the layers in 3 different "display type" modes:

mm/sec   (speed)

mm extrusion per mm move

mm^3/sec   (aka flow)

 

And both even and odd layers were the same.  However...

 

 

I also noticed that every other layer has more walls - thicker walls!  One layer has 3 shells to the wall (3 passes) and the next will have 4 shells.  They alternate.  This could explain it!  So I played with settings in cura.  It's:

alternate extra wall

 

You have it checked.  However the older 3mf file I got from you did not have that checked.  So I don't think this will make any difference.  😞