Slashee_the_Cow

Here's an updated one: fixes a couple of important bugs I noticed (was affecting Z moves during relative positioning and messed up comments so they became part of the command which made it invalid)
ZOffset.zip

I was writing this up while @FredFish was typing and their way is much much better:
@FredFish's superior way:
I'm starting with my coin with no head on it:

I've made the head a separate model, so I add that, and move it up to the correct height (which I know because I know how thick I made the coin model):

In the move controls, make sure you turn off Drop Down Model, or else every time you try and move it up it'll just drop back down.
It's that simple! Now a bunch of screenshots which make it look complicated without the disclaimer that it's just showing that it works:
 
 
 

Lookin' good so far. Let's pop down a to the layer below the cow head:

Mmmm, sweet, unfiltered surface lines. Now let's just pop up one layer:

It's now printing just cow head, there's no surface lines from the main coin (if there was, they'd have alternated direction). Shot from the top again quickly:

Yep, that's a cow head printed on top of a flat coin face.
 
 
And in case anyone was wondering, yes, the other side is the tail:

 
 
Stop reading here. My idea sucked.
 
 
 
 
 
 
 
 
What I was going to say that you should probably ignore:
Here's my Slashee coin:

If we go down to the main surface, there's holes for the face:

Then we create a support blocker, turn it into a modifier but for infill only, set the infill density to 100%, make sure the wall count is 0, the skin wall count is 0 and then set the skin wall count for the main model to 0:

The only problem with doing it this way is that it will do the lines for the rest of the skin, and then it will fill in the cow face, depending on your printer and settings that may be noticeable because it will be travelling over skin:

 

Looking at blade_1: same deal. Between the two blades there's only 2,437 verts. Also no measurement units provided. The one on the right doesn't even sit on the build plate (its base is higher than the left one).
 
The right one comes to a sharp point you're never going to get for the whole length of its blade.

The left one is only marginally better in that regard.
 
I mean, just look at this. You can see the individual triangles (right blade)

At first I thought that little bit at the bottom was a messed up normal, but for whatever reason it's a cut in the model:

 
Comparison: yes, this one is probably completely overkill (I treat $fn in OpenSCAD like a toy) but here's a letter I printed at 19.6 x 24 x 5mm:

How much does it take to get an overly smooth twisted J? 1,515,975 verts. As I said, complete overkill. At least by the time I got to the I, I'd turned things down a notch:

...that notch still has 4,100 verts.
 
But what about my lovely bovine avatar (which I actually use in a bunch of other places and have had merch custom made)?

Fewer verts. Only 357. But that's for a 30x30 pixelated cow avatar (completely flat on the back) with absolutely zero curves. Two swords need a hell of a lot more than 6.8x the verts required to make this cow.
 
I think I've made my point. But let's flip a coin, to be sure:

Finally, a fair comparison! 1,700 verts for a coin. And if anyone's curious, yes, I am enough of a smartarse that the other side is a tail:

AFAIK all the Creality profiles use the same generic Creality extruder profile, though it might have changed since a version that old.
You're probably just missing the nozzle definitions - in Windows go to C:\Program Files\UltiMaker Cura 5.5.0\share\cura\resources\variants\creality and copy the ones for your printer into the older version of Cura.

For whatever reason it's definitely not creating a full config file - try replacing it with this one (a pretty cut down version of my own, but should have all the important info).
 
If that doesn't work, try deleting the whole %APPDATA%\Cura directory so it has to recreate it from scratch.
 
If that doesn't work, then delete the whole Cura config folder again, uninstall Cura, download a fresh copy of the installer (just in case yours was corrupted in some very specific way while downloading it), install it and try again.
 
If that doesn't work, then hope the higher powers which are awesome people like @gr5 and @ahoeben notice I just mentioned them and have a look at this thread.
curacfg.zip

Well, I'm not saying you're a crazy old coot, but I just loaded it in 5.5 beta 1, 5.4 and 5.3.1 and (in the simulation animation, at least), they all printed the brim the way you're describing the new behaviour - left first.
 
BUT - I think I have an explanation.
I noticed you're getting so close to the edge of the build area that some of the brim just isn't being printed. I tested by both shrinking the object and (after bringing it back up to normal size) decreasing the brim (in this test to 5mm) so that it all fit in the build area. In both of of these situations the brim printed the way you'd normally expect - starts in the corner and does laps around the whole thing.
 
My guess is that because it can't do whole laps (because that would leave the build area) it's going back and forth up the left side as far as it can - to both edges of the build area - until it reaches the point where it's close enough in that it can do completely laps. It then prints the same amount on the right side (to even it up) and can now do normal laps since its path does not leave the build plate.

If you could provide the .3mf file for the project that would greatly help as a couple of screenshots aren't much to go by. I created a quick mockup similar to yours and got a sort of similar problem:

Cura 5.4 inherited some slicing bugs from the engine it uses so I thought I'd check 5.3.1 but got the same problem. Sometimes the slicing bugs can be fixed by turning down Mesh Fixes > Maximum Resolution but that didn't seem to work for me.
 
Playing around with some settings I did get an interesting interpretation when I set the line width just right:

By setting Special Modes > Surface Mode to Surface, it did solve the stray lines, but then it won't print the bottom (although you could move it up and put another mesh with a hole the right size immediately below it).

Although I can't help but notice that it's printing multiple lines, which it's not supposed to do:

I'm thinking "maybe it has something to do with how I made the model" (in OpenSCAD, created two cylinders with a difference() and then use a third to make the hole), and I can see that it's definitely seeing the gap between the two cylinders, but I'm not sure if that's the actual problem.

 
But it does slice perfectly fine in 4.13.1:

 
So I wish I could narrow down a cause (or a solution), but it's obviously something in the code somewhere in the 5.x versions. Fortunately you can have different versions of Cura installed side-by-side without any problems whatsoever (which is why I have four installed at once for testing) so unless someone has better detective skills than me my answer is just to use 4.13.1 when you have a situation like this come up.

Flatpacks have to do with Linux so if you're running Windows or macOS you don't have to worry about it.
 
To set up the plugin, open Cura, go to Extensions > Auto Towers > Settings (it's right at the bottom). Then you just need to put in the full path to where the OpenSCAD executable is, in my case (probably the default) it's C:\Program Files\OpenSCAD\openscad.exe
 
(This is assuming you have OpenSCAD installed already, if not, you can get it from here)

Windows: C:\Users\<your username>\AppData\roaming\cura\<cura version>\quality_changes\
Linux: Can't remember off the top of my head, if you need that lemme know and I'll look it up.
Mac: Can't help you.

Sorry for not replying, I understood that, it's just... I was pretty stumped.
I was able to successfully recreate your problem after moving things back into place and saving as a new file, then loading it again. I also thought it may be the big object in the centre for some reason, but I deleted that and positioned everything else properly and saved as a new file and same problem. Just to confirm I wasn't crazy, I made my own file like yours and it worked fine. But...
I think I figured out the problem. Somehow - and I have no idea how - the transform origins (that's where the model says it is) seem to have gotten messed up. Cura is placing the transform origins of the model in the correct place, but where the models actually are has moved away from their transform origins.
 
Better...
I think I figured out how to fix it. For this you'll need the Mesh Tools plugin from the ever awesome @ahoeben (forgot how to spell your username earlier - sorry). Anyway,
Install the plugin, and restart Cura Load your file and move everything back into position Select all the objects (you can do this from the object list in the bottom left, just click the one at the top, hold shift and click the one at the bottom) Right click anywhere in the 3D view and select Mesh Tools > Reset origin to center of mesh That should fix it. It did for me. I saved as a different file, reloaded that and everything loaded in the right place.

Go to Top / Bottom and turn on Monotonic Top/Bottom Order

Cura is printing it all as a single object:

 
AFAIK, STL files can only contain one body. I know the idea with PiP stuff is that you only have to print a single file (usually) but with these settings it's being printed and all the hinge parts are being merged with the pin. There's no way anywhere near the default settings will let you do this. Using no infill might get you close (because there's no infill in the hinge parts that will stick to the pin) but it would be impossible to print. You could use a low infill and try and use the hinge by breaking what little infill is there, but the rest of the print would be incredibly weak because of it.
 
There might be a correct bunch of settings to get it to print the way it's supposed to work - but I've played around with the file a bit and can't find them.
 
If there are instructions you need to follow for how to print it, it would be pretty useful to see them. It might also help if you could please save the project as a 3mf file (File > Save Project) just before you'd export the g-code, as that will contain the print settings you're trying to use. While we're at it, it might help to include the g-code file itself to see how it's trying to get the printer to print the hinge.

Not really a Cura sensitivity, more just common practice when it comes to printing that if you have a flat face, you print on that, unless you have a good reason not to, like if orienting the model that way would require three bazillion tons of support somewhere, or you know you get better quality on a horizontal/vertical surface and you have a showcase part you want to make sure is oriented the way where it will print with the best quality.
 
If I don't have a flat face (or I have a good reason not to use it) I usually lift the model off the plate by a few (depending on the model, usually 3-5) millimetres (in Cura you might have to open the move tool - the arrows in the left sidebar - and turn off Drop Down Model, which makes it so that automatically the lowest part of the model will always be moved down to touch the build plate) and add supports below it. That way whatever is facing the bottom doesn't suffer the common pitfalls of being on the bottom (like if the plate isn't clean it'll pick it up, sometimes the bottom layer can get a bit squished, stuff like that) and it can adhere to the support instead of the bed (usually adheres a lot better to itself than the bed).
 
If that results in it wanting to print a bunch of supports where they're not needed, first you can try in the print settings, change Support > Support Placement to Touching Buildplate which will make it only try and support areas which have a direct line to the baseplate (i.e. not inside the model). You could also add support blockers - in the left sidebar, the icon that looks like the support icon but with an x at the bottom right, open that, click somewhere on your model and it will create one (that looks like a pathetic little cube). It will appear in the object list in the bottom left (if it's not expanded, click the ˄ next to Object List), so you can then select it, move it around, scale and rotate it like you can with a model. If you want to really get into customising support blockers, then you should install a plugin like (or exactly) this one.

Sorry, my eyes got buried deep in the ocean of most-people-can't-understand-why-I-find-it-so-interesting log data. Stupid question that I'm obligated to ask (because I know from experience smart people miss the obvious things), but you did have all of these turned off, right?

If having no plugins in fixes it, then my guess would be
    a) You forgot to turn off plugin update checks
    b) Due to some bug it ignored you changing the setting to turn off plugin update checks
    c) One of the plugins was phoning home
    d) I'm guessing if you're worried about it phoning home you probably don't sign in with an Ultimaker account so it wouldn't be syncing your profile with the cloud.
 
As for your printing problem: are you using Cura 5.4? It has some known bugs, most have to do with slicing, but try using 5.3.1 (you can have them installed side by side) and see if that makes any difference.
 
(I'm sorry to everyone who has a problem with how most of my help posts end with "try 5.3.1" but it's a valid troubleshooting step, damnit)

It's already well known that Cura 5.4 has some slicing bugs. I'm pretty sure it's near the top of their to-do list.
 
Sometimes the problem can be mitigated by going into the print settings, Mesh Fixes > Maximum Resolution. 0.5mm is a good place to start and if that doesn't work try going down in 0.1mm increments, but this workaround can't be relied upon to work.

Try this, although it's pretty crude and modifies every line in the g-code which isn't a comment. Copy AddSentenceNumbers.py file inside the zip file I attached into the scripts folder in your Cura configuration folder (if you don't know where that is, in Cura, go to Help > Show Configuration Folder). Restart Cura.
 
In the Cura menus go to Extensions > Post Processing > Modify G-Code. That should bring up a window with post processing scripts (you might not have any turned on). Click Add a script, and choose Add Sentence Numbers. Then just set the options to the right of that (Sentence Number Prefix - what needs to start the line - in your case just put N in that box) and if necessary change the starting number (surely someone has a printer which is zero-based).
 
Oh, and please let me know how it goes. Seeing the results in g-code on my computer is one thing but knowing if something actually works in a real world situation is something else entirely.
 
AddSentenceNumbers.zip

To my (somewhat) trained eye, that's definitely possible. In your second photo, see how instead of straight lines (in the good spots) there's a lot of bits that look like it got a bit of filament and pulled it instead of smoothly coming out? That could be underextrusion - the printer isn't extruding as much as it should, and if it's having trouble pulling more filament in as it needs it then the pressure in the nozzle will definitely drop, and it needs enough pressure to actually spit out filament. And if your filament is only getting stuck at certain parts (how does filament get stuck on a spool, anyway?) that would explain why most of it is fine.
 
What extruder are you using now? I've never had a problem with the Bowden extruder that came with my Ender-3 v2 Neo... though I've only had it a couple of months, so too early to properly call it. If you're using a Bowden extruder, your Retraction Distance setting is way too low (given how much filament is in the tube to the hot end, you do need to pull back a bit) and your Retraction Speed is too high.
 
Also, one thing I've definitely found messing around with 3D printers - if it ain't broke, don't fix it. Don't use a different extruder just because you have one (whereas if your extruder is broken and you have another one - quite convenient).
 
Some suggestions I can offer without messing with extruders (hardware):
Use a smaller nozzle - yes, it'll take longer to print, but it also reduces the flow rate of filament required, so it's easier for an extruder to keep up. Are you printing PLA or did you forget to change that in the profile? Cause I've never seen PLA printed anywhere near that hot. In the print settings, you could try turning up Material > Flow > Outer Wall Flow just a smidge (I'd guesstimate about 105%). This will give the printer a little more filament when printing the outer walls, which could help it keep up with the lines it needs to do (or fill any gaps, etc.). You definitely don't want to overdo that one or it'll result in overextrusion (the printer is pushing out more filament than it needs for that feature - can lead to blobs and stringing). Or of course it could have nothing to do with extrusion. But that would be my first guess based on the pictures (much as I don't want to have surface problems, I can't wait for the moment I do, cause it gives me an excuse to break out my macro lens).

Don't worry, we don't ask questions here. Besides, there are plenty of free models available.
 
I've been 3D printing for 10 years and always used Cura. Gotta use something to slice it, there's no way in hell I'm writing megabytes of gcode myself.
 
Here's where I actually try to help: open the print settings at the top right and go to the Cooling section. You might have to choose to show custom settings and then click the button that looks like three horizontal lines and choose "all". In the Cooling section there's a setting called Minimum Speed. There's no real "correct" number here, it depends on your printer and the material you're using. If there's a blue circle arrow icon next to it, that means it's been changed, click that button to reset it to default.
 
I think the default settings are pretty generic, mine is at 10mm/s. try setting it somewhere around there and see if you can slice. There's also the Minimum Layer Time setting above it, again by default mine is at 10s. These control the minimum time it will take to print each layer to give the material a chance to properly cool before it lays more on top.
 
If both of these settings seem normal, then it probably needs some further examination in detail. If you can save the project (go to File menu, then Save Project) and upload the .3mf file here (you can just click+drag it into a post/reply box and it'll upload) then us nutjobs enthusiasts can have a look in more detail; the project file includes your printer's settings and all the print settings. It also includes the model file, we're an honest bunch around here so on behalf of all the regular posters on the forum, I promise we won't share it, and we'll only print it if necessary to test it. If you're not comfortable with that, then if you could find another model (you could download something from Thingiverse, plenty of cool stuff there) that has the same problem you can upload the project file for that.

THIS WAS MARKED AS THE SOLUTION AT THE TIME BUT NOW YOU CAN DOWNLOAD THE PROFILE MANUALLY, INSTRUCTIONS HERE
 
I'm guessing it's so new Cura doesn't have a profile for it. The profile for the Ender-3/Ender-3 v2 should work fine, just pick that from the list.

Material > Flow: Cura calculates the flow rate based on wall width, height, length and speed. This lets you override it as a percentage of what Cura has calculated. The idea is that if your system is partially clogged or something, you can increase the flow to increase the amount of material being pushed through to compensate, or if your printer is misbehaving and overextruding, you can compensate for that. Some people (myself included) use the option to increase flow rate for the first layer, only a little bit in my case (105%) just to make sure a decent amount of material gets through which helps adhesion.
 
Speed > Flow Equalization Ratio: Some printers can take a fraction of a second to change the flow rate after receiving the g-code for it. Depending on the print speed, the head could have moved a few millimetres by the time the flow rate actually adjusts and you get the line width you want, especially if you're using a Bowden extruder (applies to the Ender 3 v2) since there's still the filament in the tube between the feeder and extruder to go through before the adjustment kicks in.
Cura can change the speed of the print head to compensate for this, moving faster or slower for a bit while waiting for the flow rate change to take effect so you still get the line width you want. This is 100%, and recommended if you have a Bowden extruder. It can rely entirely on the printer to change the flow rate and not use g-code to compensate at all. This is 0%. I'm still not sure if you want to set it this low even if you have a direct drive extruder. It's best to just leave it at the default setting for your printer's profile. If in doubt, increase it, but you should probably leave as is.
 
Finally: I have an Ender 3 v2 Neo so I'm not sure if mine works exactly the same as yours, but when I change settings using the screen it does override the g-code, but I haven't tested whether those changes persist if the g-code ever includes an instruction to change it.

Don't worry about it. These days Windows automatically mounts flash drives and memory cards in a way where you can just unplug them without loss... as long as you're not currently writing a file, but then only that file will be corrupted.
 
My best guestimate as to answer? I don't know if a program needs administrative privileges to eject drives, but Windows 11 clamps down on the elevated privileges thing a bit and makes the whole process a bit more involved in an effort to protect idiots from themselves. (Not saying you're an idiot, but there's enough out there)

Okay so this may be one of the kludgiest kludges I've done and I can't guarantee it won't break anything else, but:
If you go to C:\Program Files\UltiMaker Cura 5.4.0\share\cura\plugins\ (or wherever the installation directory for your version is) there should be a folder called RemovableDriveOutputDevice. Close Cura if it's open, and try moving that folder anywhere on your computer that isn't in a Cura installation (just moving it to my documents is fine), you might get a prompt saying you need permission to move something out of Program Files, just say yes. I say move with emphasis because in case it breaks something else (I've managed to get half the UI to not show up just by editing one line in a configuration file which has almost nothing to do with the UI) you can just move it back instead of reinstalling Cura.

Probably should have been more clear. My bad:
As long as you have supports on, overhangs will be fine if you print outside to inside, it will just increase the angle where it has to use supports instead of natural overhangs (e.g. while you might be able to print overhangs at 55° inside to outside, outside to inside it might only be able to do 65° or something). If you're relying on overhangs that need to not have support, it might be worth testing what sort of overhang you can do outside to inside, just to see if you can get away with it.
 
Coasting: you should probably leave it off (explanation follows) there's a possibility it's the culprit. I know it's mainly used to hide the Z seam (which based on your picture appears to be the corner on the left for most of it but not in the area near the port, I can't see where it is there, but Cura does like to hide it near corners) but I don't know if it will affect anywhere that's not near the Z seam. It does result in underextrusion where it's used, and I can actually see that seems to be affecting the print quality (near the lumpy Z seam on the left, to the left of it going around the corner is much less smooth than after the seam).
 
Also about the print speed: on my profile I have walls set to 25mm/s, just to make sure they have a good chance to adhere before it starts laying down other stuff. But it really depends on your printer (unless you happen to have an Ender-3 v2 Neo like me) because you can't really do a proper comparison between different models.
 
If you could provide the Cura project file (.3mf) for this it might help to see if there's anything else that seems like it could cause a problem.

Cura 5.4 has some major problems when it comes to wall placement in certain situations. Try using Cura 5.3 instead and see if that works better.