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Ender 3 printing fails with several Cura profiles
I have just purchased the Creality Ender 3 Printer and tried to print the model that comes with it on the SD card and the print was completed successfully with amazing quality details. So far, so good. After that, I downloaded Cura 3D printing software and installed it on my machine, and then tried to slice a model that I had just made with Fusion 360.
On the first try, I chose the standard quality Cura profile and saved it to the printer to print it but the print failed in the way the uploaded video. After playing around with some settings and trying to use some of the profiles that I found online, the same case with each new profile so I came across an idea if there is a way to extract the settings from the G-code file within the printer SD card and use to print the new 3D model.
Is there a way to extract the profile settings from in my case the cat3.5h.gcode file?
Or any other working solution for my problem such as a good cura profile to print with PLA filament
Video of print failure

So, the default models print fine, also after all your efforts changing it to print your own models? It seems your offset it wrong, it does not home correctly, what has changed between the SD card model prints and the printing of your own models?

The video is not viewable anymore, please re-upload and take screenshots so that you can support the video once it is not available anymore.

That is not your Cura settings, it's just because your nozzle is too high off the print bed.
Any profile you use will fail unless you correct the nozzle height. Look up instructions for bed levelling on an Ender 3. It's pretty easy to do.

As the question is specifically asking for profile settings and not the problem with the Z-offset, this answer addresses the question at hand:

Is there a way to extract the profile settings from in my case the cat3.5h.gcode file?

No, you cannot get the profile settings from the G-code file.
But, looking at the video, your nozzle is way too far from the bed. It looks as if the bed is too low (loosen the leveling screws) or lower the Z endstop.
Note that slicer settings in Cura do not affect the distance between the bed and the nozzle (this much as shown in the video), unless:

You have installed a plugin allowing you to create an extra offset between the bed and the nozzle, or
your model has not been dropped to the heated bed (unlikely, as this requires you to manually turn this off in the settings).


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Z-axis Calibration Fault in Prusa i3 MK3S
When I give the print command from Pronterface this how it's printing. The Z value is 10.00, can't solve the issue even after first layer calibration being carried out.

More details are required for a sensible answer.

The material is PLA. I have clearly put forward the necessary details if you are in want of further details, please specify the information you need.

Take a look at this answer to see what minimal details are required. Also, please [edit] and add any additional info to the question and not in the comments. Thanks.

... solve the issue event after... - Should that be ... solve the issue even after...??

Reading your question, it seems that the Prusa i3 mk3 (which I also have) is set up for z=0 to be the proper height.
I do not use pronterface, so I don't know what special failures it may be causing.  If the Prusa is calibrated for z=0 to be at bed level, and the printer is printing at z=10, and shows z=10 on the UI, then it is likely that it is being programmed for z=10.  The question is, why?
Because the printer is calibrated, and is reporting that Z=10 at the point of failure, I do not suspect a mechanical problem with the printer.
I have sliced objects that were not properly touching the bed, which has caused this kind of offset.  Perhaps you could check that the object appears to be flat on the bed before you slice.  I had one case where a very thin spike stuck out of the mesh and lifted the object up (in the virtual slicer space) so that only the spike touched the bed, and since the spike was so small, it generated no extrusions.
There may also be calibration functions of pronterface to allow for adjustment to printers that are not properly calibrated.  Since I don't use pronterface, I don't know it, but I would suggest reviewing all the deep and hidden menues for something to tweek.

source: Stack Exchange

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

sort: votes


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Unusual issue with skin on a resin vat?
I filled up my resin vat yesterday afternoon with Elegoo standard gray resin. I used the dregs of an older bottle nearing the end of it recommended shelf life.
I printed a short print (approximately 1 1/2 hours), removed the print and then left the printer overnight. The resin vat was uncovered, but I had the red plastic top that comes with the printer squarely in place, and a third party black insulated printer cover covering the entire printer down to the feet. No gaps.
The printer should have been entirely blacked out except for a period of about 1 hour where it only had the red plastic cover on it when the printer was illuminated with artificial light (Warm white LED light panels).
When I came to use my printer again the following morning there was a thick skin of resin on the top of the tank.
This is a problem that I've never experienced before.
Could this be due to the resin's age, or is it likely that someone removed the cover of my printer for some reason (I don't know what reason, it's not really important right now), or is there another possible explanation, such as a contaminate (There are probably over 100 different chemicals or substances in the same area as the printer).
Drops of resin on my silicon mat that I hadn't bothered to clean up were still tacky, despite being exposed all afternoon and all night.

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


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What causes no display and no USB connection on my Anycubic Chiron?
I have an Anycubic Chiron with a Trigorilla controller board with a chip labeled ATmega2560 16U TW 355e3f 1833amw - However I could not find a link to the board, and there is no more info than Trigorilla on it. The power supply seems to work fine - green LED on, fan on. The middle piece has a red LED labeled "DC" in red.
My problem is that the board seems to not work. I just installed it. You can see all the connections in the photos. The display does not light up. My connected PC does not recognize a USB input either. I have installed the driver of the printer on the official Anycubic website prior to testing. I have not restarted my computer though - but the display should light up anyway, I figured.

This is most probably a power issue, no power to the display is an important hint. Note that if the power supply unit (PSU) shows a green LED, it doesn't imply that the PSU is working.
The Trigorilla board can still be found in various online shops, this isn't an uncommon board.
Furthermore, you should look into the fuses and measure them through with a multimeter; although these are recoverable fuses according to the documenttion:

Voltage input at super wide range, short-circuit protection:
TriGorilla adopts DC - DC step-down scheme design and Recoverable fuse for short-circuit protection, improving the MEGA2560 board serious heating problem,
Allowing any power supply from 10 V-30 V.

There are reported issues with the fuses being blown and not recovering.
In order to figure out what the problem is you need to do some troubleshooting. Measure the fuses (note that in case the fuses are unrecoverably blown, you need to find out why; as replacing them without fixing the short will blow them again), use a different power supply, or test the power supply on a different device where several amps are drwan, e.g. directly heat the heated bed from the PSU for a short while.


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Gaps between perimeter walls on only part of the print
So I'm having a bit of a strange issue where I'm getting gaps between perimeter walls, but only on part of the print. Even more strangely, it doesn't happen with every print, though it will happen consistently on the same model if I print it more than once.
I know the go-to answer for an issue like this is "You're under-extruding. Fix your e-steps or increase your extrusion multiplier", however I'm not sure that's the only issue at play here. I did try increasing my extrusion multiplier (tried both 1.05 and 1.10), and while the issue did improve, it didn't fully solve it. The print shown below was printed with an extrusion multiplier of 1.00.
Also worth noting is that there is a bulge in the side of the print toward the bottom, but I'm not sure if it's related to the perimeter wall gaps issue. I have no idea what would cause that.

Basic Info
Printer: Ender 3 Pro
Filament: Hatchbox PLA ("gray blue")
Slicer Software: Slic3r

Slicer Settings

Note: I am only adding the settings I believe are relevant to the question. If you would like to see a setting not shown here, please let me know and I'll add it.

Print temperature: 200 °C
Bed temperature: 50 °C
Installed nozzle is 0.6 mm.

Print Images
This first picture is to show the orientation of the print on the print bed:

You are using a larger than "standard 0.4 mm" nozzle. Large diameter nozzles cause flow volume to increase when the extruder etrusion speed is kept the same as for the standard nozzle which can cause extruding problems like underextruding.
The nozzle diameter increase appears marginal (as in "it is just an extra 0.2 mm in diameter", but actaully the nozzle increases 50 % in diameter), but has significant effects on the volume flow of the extrusion.
As seen from the table below, when increasing the nozzle diameter for the same printing speed, the volume flow increases from 1.26 mm³/s to 4.24 mm³/s which is a 337.5 % increase of the flow for the selected layer height (0.3 mm).

This increased flow must be created by your extruder/nozzle assembly and might fall out of the range it can produce for the current setting. Generally this requires you to increase the printing temperature or decrease the printing speed.

Thank you, I hadn't even considered that the flow volume might be an issue. I finally calibrated my e-steps last night. Doing that and printing a little bit slower seems to have solved the issue.

I had this in 3 new Ender 3 pro's.   It was the nozzle was too small. I checked the output of the nozzles by extruding and measuring the filament after it hardened right at the nozzle.  A good nozzle will measure exactly to the size.

The amount of material the extruder is pushing, not the nozzle size, determines the width of extrusions.


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How to use a 3018 CNC Offline Controller in Marlin?
I need to know what the name of this controller is in Marlin:

Surprisingly, I plugged it into AUX-2 on a MKS Gen L V1.0 with mostly default Marlin settings. It powers on and the buttons work. But whatever it is sending to the printerboard, the printerboard does not respond to. Also, it seems to block the connection to the computer when it is connected? SO maybe AUX-2 is the wrong port?
I unscrewed the case and tried to look for any markings on the PCB. There were none. I'm not sure what I should be looking for when I open it up.
I have bought a couple 3018 CNCs over the years and both have come with this controller, sold by different sellers.


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Klipper Input frequency Chart not making sense
In all of the guides i've read it says to read this chart and wherever the peak is for your axis you tested that is the number you set for your freq. However, my chart on the X axis the peak is about 17 but the chart says the recommended value is 39. Why?


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How much weight can the x motor support?
Speaking about any printer, in a general sense.
If I load up the X carriage with two hotends and two stepper motors in a direct-drive-way... Then surely the force applied by the x stepper motor will not translate to the intended distance of the carriage.
What I am getting to is: How do you ensure changing carriage weight does not change travel distance?
Where would you change something? Do you start at software-level, like there being a variable and an algorithm which you feed the weight to, or do you change the stepper motor, and so on?

Load does not change the distance a stepper travels unless it misses steps. That's why it's called a stepper and not a normal open-loop motor - it moves in discrete steps that are completed in their entirety or not at all.
If the motor can't move (actually: accelerate) the load you've given it, no amount of software-level stuff will change that. Giving it more current might. But generally, unless you've built an extremely rigid machine for extremely high usable acceleration/speed, these motors have more power than they can use without going way beyond the point where your print quality becomes unacceptable. For example the X motor on a stock Ender 3 can accelerate the stock carriage at nearly 100000 mm/s² if you really want it to (with input shaping; without it, the resonances will give you drastically increased reaction forces that make it skip steps much sooner, maybe at 6000-10000 mm/s²).
A more massive toolhead will be harder to accelerate, but the way you solve this is by using lower acceleration, or putting on a more powerful X motor. However, unless you're also doing serious vibration-reduction modifications to go with the increased mass, you won't even want to have more acceleration. The ringing will be bad.

Thank you very, very much for taking the time to educate on this topic. It is very much appreciated. It will surely help many more in the future.


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Can level every where except the center of the bed
Every time I try to level my Ender 3 v2 I get all the corners perfect when pulling paper in between. But for some reason, if all the corners are good the middle/center still has a bigger gap like 2-3 paper sheets. The prints do still look “OK” but I do have some sections where the lines won’t melt together.

A trick that helps a little is to put some kapton tape on the underside of the bed in areas that are too low - the glass has a little flex and it's possible to remove some warping that way, though 2-3 sheets of paper worth may be too much, plus you compromise heat transfer a bit.
If the tape isn't enough you can either get a new bed plate (either glass or upgrade to magnetic) or - IMO best option - get an ABL probe. It will compensate for the warping and make your life much easier.


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How can I improve my print quality?
Printing on an Ender 3 V2 Neo, using Cura to slice, PETG-filament.
I printed a 3DBenchy and there is a fair bit of stringing and the layers are showing. The roof looks a little bit weird, the printer has printed it in a stairy kind of way. Also there are ripples all over the print.

0.4mm Nozzle
PETG Standard Quality 0.2mm
Layer Height 0.2mm
Line Width 0.4mm
Wall Thickness 2.0mm
Wall Line Count 5
Top/Bottom Thickness 0.8
Infill Density 20%
Infill Pattern Cubic
Print Temp 240 Celsius
Build Plate Temp 80 Celsius
Flow 97.0%
Print Speed 50.0 mm/s
Wall Speed 25.0 mm/s
Retraction Distance 5.0 mm
Retraction Speed 45.0 mm/s
Retract at Layer Change Off
Retract Before Outer Wall On
Avoid Supports When Traveling On
Fan Speed 35.0 %

I am a beginner in 3D printing and haven't spent any time further tuning it than the set-up. Thank you for helping.


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What is an appropriate filament to 3D print a replacement microwave turntable ring?
I recently had the unfortunate experience of someone in my household accidentally breaking the microwave turntable ring. Considering the replacement cost of a new tray ring is upwards of $70, I'm exploring the option of 3D printing a replacement. However, I'm not sure which 3D printing material would be best suited for this task. Here are some key points to consider:

I'm aware that certain 3D printers are limited in terms of filament compatibility, but fortunately, I own a Bambu Lab X1 Carbon that supports a wide range of filament types.
Given the cost of the replacement part, affordability is a factor. I'd prefer a material that comes in at a lower price point than $70.
Durability and heat resistance are crucial factors since the replacement part will be used in a microwave.

With these considerations in mind, could anyone recommend the most suitable 3D printing material for crafting a sturdy and heat-resistant replacement microwave turntable ring using the capabilities of a Bambu Lab X1 Carbon printer? Your insights would be greatly appreciated!

Polypropylene .

What was the original made from? Did it have a recycling symbol, or does the replacement's website say?

@TheTridentGuysupportsUkraine it doesn't have a recycling symbol on it. None of the replacement parts specify what material it's made of.

I just came across another site which said:
PPS+GF40%,V0,XP. I believe PPS is polyphenylene sulfide but I'm not quite sure what the other information means or if it's even relevant.

@PeteK68 GF ususally means glass fibre.

According to multiple sources on the internet, PP is considered microwave safe and that's what most "microwave safe" plastic containers are made of.
But that's not the entire story. The best way to figure out if a material will deteriorate in microwave is, well .... microwave it :) If it survives prolonged exposure it's unlikely to have a problem as a mechanical part as it's not in contact with food.

Here are few Thingiverse models with claims (either by author or in makes) of being made from "good old" PLA.
https://www.thingiverse.com/thing:1418362
https://www.thingiverse.com/thing:2460702
Here's one using ABS
https://www.thingiverse.com/thing:385288
How safe it is? Who knows.

@Griffin That seems like a short answer, please post a more elaborate version as an actual answer!


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3DF Zephyr -> Fusion 360 set mesh dimensions
I have managed to successfully scan an object with 3DF Zephyr Free, and have exported the mesh to a .obj file (only filetype supported).
Once I have inserted the mesh in Fusion 360, how do I set the dimensions of the mesh?
When I import the mesh into Bambu Studio, it shows me the bounding box dimensions. So I can scale it accordingly. I can't even get a bounding box to display in Fusion 360.


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Creating a plastic scallion whistle
Recently my uncle-in-law taught me to make a whistle using a scallion stem. You can watch this video to see the process. Of course, the video shows making a whistle with an onion stem. But a scallion is also a plant and produces the same sound.
Since it rots after just hours, I'm wondering to make a plastic whistle with the same thickness and flexibility to produce the same sound (of course, one end is thinner, and the inner layers of scallion should be removed).
Which kind of plastic is better for this to be used in 3D printing? Can I also make holes in it to produce a flute?


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Anycubic Kobra Go bed leveling
I can’t figure out what the issue is. The far side of the bed (Y-axis) print won’t adhere because the extruder is too far off while on the near side is too thin. I have tried all the troubleshooting tips I can find online and nothing worked. Even as a last resort, I tried shimming the far-side bed screws and still have the same results after auto bed leveling.

If you did not resolve this, you can try a couple of things:
You'd need OctoPrint and the "bedvisualizer" plugin installed.
I've had a similar problem with my Kobra standard and found out that it was totally off-level.
If the issues persist, please download/install both and send a screen capture of the bed level so we can go from there!

Setting up OctoPrint on Windows

Bed Level Visualizer plugin


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SuperSlicer model malfunction?
I just want to print this shower curtain ring:

For some reason SuperSlicer doens't like the circles and after slicing the model looks like this in preview.
What is the issue with the slicer? Is there any setting that I might have and ruin the model?
Thanks

Using the link, I downloaded the single ring and Meshmixer says there are no flaws in the model. PrusaSlicer also slices the file without complications. Have you tried another slicer in order to have additional data?

@fred_dot_u I removed the preset that I originally had and reimport it and everything is fine now. Possible that the config got corrupted

Good deal. Consider to create an answer to your own question, give it a day and mark it correct with the check mark.

At the moment I didn't find the exactly what option from config did this but after reimporting the preset everything is back to normal(possible something got corrupted in the preset or the app, I don't know for sure).
I will still research to see what caused the issue for feature.
Thanks all


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Why is the Z probe offset easily adjustable in the printer UI, but not the X/Y probe offset?
I should mention that this is my experience with Marlin. I can adjust the Z offset all I want in the UI, but not the X/Y offset. If you reinstall the probe, I've heard you may need to adjust the Z offset (makes sense, you might not mount in the exact same way). I assume X/Y offsets get affected as well, so it doesn't make much sense to me that you'd have to rebuild the firmware to adjust those values. Maybe they're less sensitive to change? Anyways, not sure what makes them special enough to exclude from the UI.
My printer seems to work okay using a prebuilt firmware, though it could just as easily be pointlessly leveling 50 mm off of the nozzle for all I know.

Usually you install the sensor once and keep it unchanged for years. Nozzle, though, is an element people, depending on printer usage, replace semi-frequently and the Z offset will change with different nozzles, different tightness, etc.

XY probe offset has very little importance - your bed level changes very little over distances of order of 1 cm, so 1 cm of error in XY probe offset is negligible. Meanwhile, even 0.05 mm Z offset difference impacts first-layer adhesion significantly.

On a separate note, you don't need to rebuild the firmware to change the probe offset. You just need an interface (USB cable) and terminal (Pronterface) that allows you to communicate with the printer using G-code. First issue M501 to load the configuration from EEPROM, then M851 with the right X, Y values to set the XY offset, then M500 to save the changes to the config to EEPROM. No firmware update is needed.


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Ender 3 - Prints above bed, but the purge/start line is perfect
I'm trying to print after letting the printer taking a break for a few months. Haven't touched anything, but it starts with the purge/start line and it looks good. When it tries to print my model the nozzle is 1 mm above the bed. Tried with both pla/petg, different Cura slicer configs (both default and CHEPs) but nothing makes any difference. Have anyone experience this?
Picture of the purge/start layer, looks ok:

This is when it starts printing the rest, you can see that the nozzle is a few milimeters above the bed:

I've tried level the bed (with the bed and nozzle heated) but does not help.
First 50 lines of G-code:
;FLAVOR:Marlin
;TIME:3655
;Filament used: 3.24955m
;Layer height: 0.28
;MINX:93.425
;MINY:80.447
;MINZ:0.28
;MAXX:141.575
;MAXY:154.549
;MAXZ:7
;Generated with Cura_SteamEngine 5.2.1
M140 S50
M105
M190 S50
M104 S200
M105
M109 S200
M82 ;absolute extrusion mode
; Ender 3 Custom Start G-code
G92 E0 ; Reset Extruder
G28 ; Home all axes
G1 Z2.0 F3000 ; Move Z Axis up little to prevent scratching of Heat Bed
G1 X0.1 Y20 Z0.3 F5000.0 ; Move to start position
G1 X0.1 Y200.0 Z0.3 F1500.0 E15 ; Draw the first line
G1 X0.4 Y200.0 Z0.3 F5000.0 ; Move to side a little
G1 X0.4 Y20 Z0.3 F1500.0 E30 ; Draw the second line
G92 E0 ; Reset Extruder
G1 Z2.0 F3000 ; Move Z Axis up little to prevent scratching of Heat Bed
G1 X5 Y20 Z0.3 F5000.0 ; Move over to prevent blob squish
G92 E0
G92 E0
G1 F2700 E-5
;LAYER_COUNT:25
;LAYER:0
M107
;MESH:Bodacious Lappi (2).stl
G0 F6000 X98.561 Y101.407 Z0.28
;TYPE:WALL-INNER
G1 F2700 E0
G1 F1073.8 X98.219 Y101.649 E0.0218
G1 F926.6 X96.942 Y101.649 E0.0988
G1 F848.1 X95.665 Y101.65 E0.18294
G1 F969.7 X95.231 Y101.371 E0.21267
G1 F1200 X95.065 Y101.043 E0.22979
G1 X95.065 Y95.95 E0.46694
G1 X95.231 Y95.534 E0.4878
G1 F1073.8 X95.596 Y95.255 E0.51171
G1 F924.9 X96.873 Y95.255 E0.58886
G1 F846.6 X98.15 Y95.256 E0.67315
G1 F969.7 X98.557 Y95.495 E0.70034

Weird. The initial line is extruded at Z=0.3 while the first layer starts on Z=0.28 and the only non-motion things that happen is switching the blower off, and messing with extrusion parameters. I really can't tell what is wrong, but it's definitely none of the trivial stuff. ...Put M90 before M82 in the startup G-code. Not sure if it will help, but worth a try.

The default purge line is supposed to be thick. So thick that it's actually problematic for some materials. Thus, it's possible for it to come out "thin but adhering to the bed just fine" if your distance from the nozzle to the bed is significantly too high. You probably just need to adjust your bed height.

Don't know if you fixed it yet but this happened to me today. There's an eccentric nut on the right. Tighten it so it doesn't wobble but not so tight that it doesn't move.


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Nozzle temp always reads 236 °C, even when it's room temp (Ender3 V2 Neo)
My first 3D printer, an Ender 3 V2 Neo.  The original issue I was working to address was a clogged nozzle.  The heat-block was caked in melted filament.  At this point, I just chalked it up to a gap forming between the Bowden tube and the nozzle.  I decided it was enough to replace the nozzle and the stock tubing.  However, in my vain attempts to replace the nozzle while it was at room temperature, I had gone to town holding the heat-block in my left hand with pliers, and the nozzle with the included cone wrench with my right.
After learning why it's necessary to risk burning your fingers on a 240 °C nozzle while performing maintenance I was able to replace the nozzle.  However, the problem carried over to nozzle #2.  After inspecting conditions I thought the issue at this point was a gap between the heat-break and the heat-block/nozzle that formed due to my earlier "repairs".
I disassembled everything, removing the heat break from the heat sink, the heat block from the heat break, and cleaned them as best as I could.  (My tom-foolery included removing the heating element from the heat block as I didn't know what a grub-screw was, and then experiencing how exciting it is when the heating element slips out of the heat block)
After putting everything back together again, the display began showing the current nozzle temperature at 236 °C.  As in 236 °C is displayed regardless of whether I just turned the printer on, or if I manually set the temperature to 200 °C.  The nozzle doesn't heat up and it's safe to touch.  If I manually set the nozzle temp to 250 °C and wait, the display will show the nozzle heating up to 250 °C, however, the nozzle's no warmer than a sunny day.
While the printer sits idle I do periodically see temperature fluctuations of plus/minus 1 °C.
Being unable to fix the problem by working on the hotend I assumed something happened to the thermistor so I purchased an entirely new (stock) hotend.
After installing it I flipped the power switch and the nozzle was still at 236 °C.
I tried to replace the firmware, first by installing 1.1.5.2, I verified it installed through the info screen but there was no change in the temperature reading.  I then installed the factory version, 1.1.4 again to no effect. (Creality's Downloads page)
All that's left is to replace the entire board which feels excessive for such a seemingly tiny issue.  Am I missing something?  I'm not able to find anything on Google that resembles my problem.

Could be a buggy temperature sensor?

If the temperature reading shows increases above 236 when heating, but can't show anything below, you have a short of approximately 300 ohms across the thermistor wires. This could be something wrong on the board or in your wiring to the hotend. You could try diagnosing this by measuring the resistance across the thermistor connector on the board. If you see somewhere around 300 ohms, the problem is on the board and unless you can find and fix the cause, you probably need to replace the board.
As an aside, if the board did not kick into thermal runaway protection during the entire time it took to heat from room temperature to over 235, during which no change in the read-back temperature occurred, the firmware has missing or broken thermal runaway protection and is unsafe to operate (severe fire hazard). You should check on this even if you get it working again.

I really suspect a defective or disconnected thermistor. Can you measure the voltage across the thermistor at the connector on the board when turned on? The value should change when you heat the hotend (use a hair dryer).
If the value does change, the error is in the firmware / board. If not, recheck your connections for continuity with a multimeter.


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G-code dialog sequence over serial interface
I'm writing a Python module that allows new tricks with printing - it already can produce G-code I can put into a file, send to the printer and print out. No problem with generating the correct codes to print.
What I want to add to it is interactive mode: connect to the printer over serial interface, then control the printer "as you go", you enter a command, the printer responds. You run a procedure, the printer executes the sequence of G-codes, then the software returns to awaiting further commands. The Marlin website provides a comprehensive reference of all G-codes for me to use. What it lacks though is an intro about the protocol as a whole, especially the busy/wait and error responses, the timing of me sending the next command in sequence.
Can someone either explain that part in sufficient detail to allow me to write the code that knows when (and if) to send the next G-code command, and/or refer me to a resource that does just that?

I think this has been answered before. Does this or more specifically, this answer your question? If not, how does the question differ?

@Oscar: The latter one is useless, it's how to do send a single fire-and-forget command, not a dialogue question. The earlier one has bare minimum about the buffer and 'ok' but the answer is so perfunctory it's nowhere near sufficient. I could post a bounty there for 'improve details' if I had the points, otherwise I'm stuck with way too little. In particular not a peep about all the possible answers that are not 'ok'. Also, came by M400 all by myself; I don't think any answer that doesn't mention it is comprehensive enough.

What do you mean by interactive mode: connect to the printer over serial interface, then control the printer "as you go", that is not clear in your question. You mean to control the printer from the printer itself when connected over serial and from code, or just interface with the printer through code only? A programming interface only is exactly as described in the latter answer I linked, only your program will be bigger with more user interaction, upon quitting you should close the serial connection. I have done this multiple times that way.

@Oscar: A shell, but you give commands in the language I provide, not directly in g-code. One your command can be one g-code command, or can be a sequence of 500. So your input is frozen until the printer completes the 500 commands. The sequence can easily be longer than Marlin's buffer, or contain unbufferable commands. You control the printer from a PC connected over USB.

Yes, I should close upon quitting the interactive shell, but not after executing one command - after a command I await further user input, with connection kept live.


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Why are the exposure times for clear and translucent resins so different?
According to the official Elegoo resin sheet, the standard layer exposure to for clear resin is 8 seconds per layer, while the translucent resin is only 3.5 seconds.
For comparison, standard Gray is 2.5.
Official Elegoo data sheet
Both resins produce a similar effect, except one has less tendency towards yellowing.
Why are their exposure times so dramatically different?

In a clear resin, which cures by light not every light particle will hit an optical active region in the resin's molecules. Especially if the layer of the resin to cure is rather thin. For a given layer thickness there's a percentage of light which will be absorbed and a percentage of this percentage will initiate the curing reactions. The more curing reactions started within a period in a given volume the faster the curing process will be finished.
Translucent materials contain particles which scatter incoming light. Of course the designers of a resin will choose particles which scatter that light while absorbing only a minimal share of it.
This will prevent the majority of photons from crossing the layer on the shortest path. This again will increase the number of initiated reactions in a given volume of resin for a constant flow of light. Of course this is some sort of tradeoff, as with too much scattering the curing speed will reduce on the distant end of the resin layer.

this is a very nice answer. In short you are saying that the UV light can easily pass through transparent resin and it can't pass as easily through opaque resin. That's probably why you wouldn't want to use pure black UV curing resins.

@Hacky, Both clear and translucent resins are supposedly transparent.


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Designing compressible camera mount
I am looking for some ideas, I am mounting an OV9281 camera sensor with an M12 lens in a waterproof box. I have designed a mount with snap-fit joints for the camera to fit too. This works successfully at one particular focus range but when I refocus the lens the height of the camera changes and it doesn’t fit in the box. I was hoping someone might have some ideas for a solution that will allow the camera to move up and down in relation to the lid when the camera is refocused and the box closed. I’ve thought of:

flexible tabs on the camera mount (I am using nylon currently and it seems there might be issues with creep?)
steel springs (hard to build into the model but should work)
Rubber washers (easy to build into the model but wouldn’t allow a lot of compression)

Does anyone have any other ideas?

It would help if we could see what the "waterproof box" looks like.

It’s a standard electronics enclosure if that helps?

Printed planar 3D springs aren't that difficult to design for print and should work sufficiently well in your case - essentially make two frames, one within the other, "suspended on a labyrinth" - a snaking thread of material that provides a lot of flex. Add more loops for more flexibility, or stack a couple such frames to provide more yield.

This is a great idea, do you know if these frames suffer from creep if compressed for long times or does the amount of material in the planar spring negate this? Thanks again, this looks like a solid solution

@tenniscelebrationparty I'm quite sure this is material-dependent and I have no idea how it depends on which material. I expect it can last at least a couple years and then you can print replacements.

spring actuated slider mounted
Your problem is basically, that the camera will stick out of the allowable space in some configurations. Such is usually due to the mounting point of the camera holder forcing a position of the components in relation to the backend of the camera.
This can be solved by mounting the components on some kind of sliding gantry and actuating it upwards with a spring. This will automatically align the camera position to the most lipside place the camera standout allows by pressing the lens protector against the lid. For adjustability of the spring pressure, absolute top position and easy swapping of springs (if needed), a grub screw could be used to adjust the position of the holder to the spring's maximum length - green in the image. By choosing a proper spring and having it at or even in the gantry, you can use somewhat standard parts, like the springs from pens, and don't need to work in as much space  under the camera but instead can use the more likely more ample space outside of the camera's moving box. Also, the gantry base plate could mount all other components.
For maximum constrained movement and least strain on the parts, it would be advisable to use a pair of guide rails on two opposing sides of the camera plate, and place the springs either on the center of the gantry or use a pair on either side of it.

This can be simplified with the sensor chosen by mounting the whole board on small spring standoffs that allow them to be compressed by the maximum difference, but such a setup might tilt the camera if no guiding is included. That could be facilitated by adding an extension plate bottom or top of the sensor which constrains the tilt of the sensor board. It might be required to shorten springs quite a lot for this.

mounting point on the camera
Currently, you explain to us, that you hold the camera on the mounting plate of the optical sensor. However, you also could mount the camera by the lens holder. As an Upside, the camera will always be at the same position relative to the lid. As a downside, you will need to account for the whole board of the optical sensor to lift with the lid and if you fix the barrel even to turn the whole board of the optical sensor to adjust focus length. Both in turn will move the whole cabling too - you might need to unplug and re-plug it for some adjustments. Also, adding or removing filters will be more complicated.


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What factors go into pushing the first layer speeds of an FDM print?
When searching for "how to increase first layer speed" and "how can I get faster first layers", the only results I get from both Google and DuckDuckGo are articles talking about printer basics.
You know the type: "make sure your bed is levelled, make sure your bed is cleaned, print the first layer slower", the articles aimed at beginners that are trying to get a print to finish.
I'm instead looking to increase the first layer speed, as I have seen several CoreXY machines being able to print the first layer at speeds clearly higher than 30mm/s.
I have a Sovol SV06 with the SV06+ hotend. So not a CoreXY... Are the faster first layers intrinsic to CoreXY? Or are there steps I can take on my SV06 to have better bed adhesion for faster first layers?
EDIT
Here's an example of what I'm talking about. A functional print being created on top of a first layer that was placed down so quickly.


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What problems to expect when operating a 3D printer on a ship?
I want to operate a 3D printer on a ship. This brings up some issues. I want to estimate how likely it is to get usable results under conditions on a moving vessel.
First, it is impossible to level the platform and keep it balanced on which I want to install the printer. Any ballasting operation will tilt the plane even when berthed. This, of course, rules out several printing technologies, such as stereolithography, laser sinter printing, etc., which rely on gravity to keep the materials in a fixed position.
In my opinion, the only technology that is more or less tolerant of slight inclinations of the printer bed is FDM.
However, a ship is also moving. Even when berthed, it will respond to waves and wind. I do not intend to use a printer in rough sea listing to 10° or more. However, under rather calm conditions (2 m wave height), we reach +/- 2° list and +/- 1° pitch easily at turn rates of 50 mrad/s. Linear accelerations are +/- 0.1 m/s2 (X and Y) and +/- 0.4 m/s2 (Z).
I'm aware that an FDM printer will be affected by acceleration and position. Position changes will alter the vector of gravity pulling on the printer's mechanics, and acceleration will superimpose another force.
Of course, an error will be introduced. How big that error is will depend primarily on the stiffness of the mechanics and slackness of bearings and support.
Has anybody had experience with a moving coordinate system (most likely on board any vehicle) while printing with an FDM printer?
What problems do I expect when using a printer with actors in the most common cartesian coordinate system (X, Y, Z) on a ship?

TLDR: Probably none. Having viewed many YouTube videos to learn about 3D printing, I have seen numerous people 3D printing in outer space, trucks, cars, a backpack, upside down, a 6-point bungee harness, etc.

@agarza good comment to encompass the overall robustness of nowadays FDM printers to acceleration.

There's a fully working 3d printer on ISS and it didn't need much modification. There's a model that prints upside down, due to space constraints. The most significant problem will be a spool holder that doesn't let the filament tangle as the spool wobbles. I recommend printing one of the auto-rewinder models intended for AMS/MMU. The second problem is all the paraphernalia you can order on-line with next day delivery if you need them. A bearing here, a non-standard screw there, short on heat-set inserts, the bowden tube fitting got damaged...

Very interesting question. Can I ask for what purpose you're planning to print on a ship?

@BobOrtiz In most cases: Replace broken things. It's a research vessel with fairly complicated machinery. If we stocked 86 of 100 possible spare parts on board right tomorrow part no. 87 will break. The other thing is, that you can't plan ahead which additional things you will need to accomodate the scientific payload aboard. Frequently we'll have to make things fit. We can weld, turn the lathe and the milling machine but there are still things you can't build that way.

@SF. Interesting thoughts. Concerning spare parts of the printer: We are used to stock the most vital spare parts for all machinery already. So we will have a close look on spare part lists of a printer model we are considering to buy of course.

@Ariser Also look into a filament dryer. In very moist air even fairly moisture-resistant filaments like PLA can start misbehaving.

While your conceptions of "leveling" might apply to SLA or SLS, they are misconceptions with respect to FDM. "Leveling" the bed in FDM is not about leveling but about squaring it with respect to the rest of the motion system. There is no need for it to be "level" with respect to gravity. FDM printers operate leaning diagonally or hanging sideways off of walls (typical in some print farm configurations with auto ejection), upside down (e.g. the Positron), or in any other configuration you like. There are even printers setup to be carried as backpacks, printing while the wearer is in motion. Being on a ship, with extremely slow changes in orientation from the movement of water and the vessel, is completely irrelevant to FDM.
If you want some numbers, the accelerations you cited, 100 mm/s² in X/Y and 400 mm/s² in Z, are at least an order of magnitude below what a decent FDM printer experiences constantly as part of printing. Nowadays, good printers print at 5000-15000 mm/s² nominal acceleration, and experience additional forces from pseudo-instantaneous changes of velocity at the boundaries between linearizes segments comparable to another 2000+ mm/s².


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Issue with PETG adhesion
I am printing on a Prusa i3 MK3 with white PETG and I face several issues when it comes to the extruder shaping the bridge and solid infill. For the record, the temperature is set at 230 °C for the first layer and at 240 °C for the others. The speed for the solid infill is at 80 mm/s. I print with an infill of 0 % and for reasons related to my work I don't want to change that and increase it. Is it a temperature issue? It's like the bridge infill doesn't stick to the perimeters.
After reading similar issues, I have increased the temperature to 250 °C and I still have the problem.

What is the temperature of your heated bed? That together with the hotend temperature, print speed, first layer height and first layer width all affect the adhesion of the first layer.

In hindsight, printing the first layer at that speed is not a good idea. Try to lower the first layer speed to something like 15mm/s

@Hacky bed is at 85-90 degrees. But it's not a first layer issue because the first layer gets printed fine. It's just the fact that it builds the perimeters and when it's about to print the bridge infill it doesn't stick to the perimeters causing it to "collapse". I used the same formula (mostly talking about the 0% infill) w PLA and didn't have that issue (i'm aware they're different of course)

your picture looks like the first layer, but I can be wrong. A first layer though, can't have a bridge infill as a bridge is something that spans over a gap. Coming back to the issue: try printing that layer a lot slower. PETG is not as "runny" as PLA in my experience and it likes to move with my nozzle.

@Hacky Maybe it looks a bit tricky to the eye in the pictures. My apologies. But if you look at the gauge you can see the first layer underneath the problem (the detached bridge infill). The model is already 4mm thick in the picture so the perimeters are already done and it has started printing the bridge.

It's an issue of 3D printer technology. Unsupported bridge like this will inevitably cause trouble. "Solid infill" is irrelevant in this model, Hacky's hack may help, but in general if you do 0% infill, you'd better know what you're doing.

Unfortunately I know of no setting like a "bridge infill - inner wall overlap" .
You can however break the top and bottom of the model up into 2 pieces. Use the "per model settings" to increase the thickness (number of walls) of the bottom part. That way the infill has some ledge to hold on to.

You could try reducing the number of perimeters from 2 to 1 only for the layer in which the bridge occurs. This leaves the second perimeter in the layer below as a bridge anchor, like shown in these two images: How to configure your slicer to properly support bridges. Or you could change the number of perimeters from 2 to 3-4 in the 3 layers below the bridge to achieve the same effect with less visible artifacts on the surface.
Other than that, you can try to reduce bridging speed and acceleration or switch to another slicer. I'm not sure if the Prusa Slicer derivatives like SuperSlicer or OrcaSlicer are better in this regard, but there's always Cura if you want to invest the effort to learn a new software.
There are quite a lot of issues with the bridging algorithms in recent Prusa Slicer versions. See the Github issue Add an option for setting bridge/perimeters overlap for a list of links.


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Cura 5.4.0 Added "Print as support" Cylinder adds support to regions where there is no model. How to limit support to those areas that need it?
I added a cylinder object to my model and changed the object type from normal to "Print as support."  After slicing, the cylinder appears as support but this support exists in areas where there is no normal model (it's just supporting air).
This article How to Add Manual Support in Cura states:

Cura offers a selection to "print as support". That will print the
whole cube as support. We just want the area under the leg within the
cube. So choose that setting from the drop down menu.

The article doesn't clearly state what that setting is and Cura 5.4.0 has no drop down menu.  How do I get the support associated with this print-as-support cylinder to be generated for only those areas that are below the normal model?

Working with manual supports like the one you added, you are fully manual, no automatic options to adjust them - they are intended to be used in situations where the automation has already failed after all.
So - select (click in the work area) the support, and use scale, translate, rotate options to make it the size that does what you want and little-to-no more. Unchecking even scaling will allow you to smoosh it into a thin ellipse which you can place under suspended edges. You can even tilt it to act as a makeshift tree support, just make it taller than needed and sink a part under the plate so the adhesion layer is wide enough. You can also overlap it in significant part with the printed object - Cura will correctly trim around the skin of the object, making sure it's supported and not permanently glued into the support.


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Equipment for starting with SLA printing
I am completely new to 3D printing and want to start with SLA printing.
I found the Anycubic Photon Mono 2 printer, but on the ordering page, there are options for "Airpure" and "Wash & Cure" machines.
I do not know what these are, nor if they are needed for SLA printing.
Can someone explain the function of these items, and if they are needed for SLA?

The Airpure is an air filtration device for use inside the SLA printer to scrub the air for fumes.
The Wash & Cure machines are to rinse the resin off of the printed model. Since the resin is UV reactant, the "Cure" part of the device is to solidify the model into a solid form. (Note: This is a two-step process)
While these devices are absolutely necessary (you could come up with other solutions) they are readily-made solutions by the same manufacturer.
I would recommend watching some YouTube videos on SLA or resin printing to understand the use of the Wash & Cure machines.

Seems like the Wash&Cure could be easily DIYed. I will watch videos on SLA, however, how is the resin cured? UV light?

Yes, there are several videos about using DIY curing setups. And yes, the resin is cured with UV light.

Thank you! One last thing. The curing has to happen at a specific time interval? Or you can literally do it the next day or week and the finished part will be fine?

Because of the chemicals in the resin, it is best to cure it as soon as possible. Not to mention that an uncured model could deform since it has not solidified.

Airpure can be replaced with a good fan and duct that sucks fumes out from the printer and vents them outdoors away from any living creatures. Not practical in many situations, but can be much cheaper if your situation allows.
I've seen a hobbyist making excellent prints where his "Wash & Cure" were a big jar with a lid, filled with isopropanol (to be shaken vigorously with the print inside) and a UV flashlight (to shine at the print from all directions).
What you really shouldn't skimp on is a good quality rebreather and eye protection.

While the information you present is not wrong, it doesn't directly answer the question of what the items are and their function. (Not trying to offend or anger, just giving helpful advice)


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Communicating with a Marlin board via Javascript and Node SerialPort
I am trying to send G-codes to my Anycubic Kobra 3D printer running on a Marlin board.
I have tried several serial communication software (terminal-based) and managed to send G28, for example, and it works. Using the exact same baud rate and port name, I am using Node SerialPort library and I am successfully connecting to the board. But the problem is that it won't accept my commands, nothing happens.
I have been trying to send G28 in ASCII and hex forms. I have also been trying with G28\n and G28\n\r.  I monitored the SerialPort with a tool while sending commands via both Cura and serial terminal. I then sent the exact same string with Node SerialPort, but it didn't work.
What is the correct format, any clues? I want to be able to send commands via Node SerialPort since I am doing my own web interface for the 3D Printer.


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How to harden / strengthen the teeth of a 3D print
I have a 3D object that I print with 0.6 mm nozzle and white PETG.  At the moment I can't print the layers in another direction since I use 3D printed threads.  The object is a de-seeder bit for the sorrel fruit.  Some of the teeth break off when using it (see red arrow showing the missing tooth that breaks off when used below).
If you want to see how it's used, I have provided an animation/video of it.

I was wondering if there was a way to increase the strength of the teeth on the bits from breaking.  I was thinking of using some type of nail hardener but was wondering if that would work or if I should try and use something else.
I'm also willing to try a different 3D material but it needs to be able to withstand summer heat in Florida in a garage which gets to be 97 °F or 36.11 °C and be printed with an E3D Revo 6 nozzle (which is like a hardened steel nozzle).  PLA will just melt/turn rubbery.

forces applied parallel to layer lines will provide the results you are experiencing. Even a surface treatment as you suggest will not add much strength. I don't have a materials suggestion, but you are on the right train of thought in that regard.

Alter geometry
You experienced one of several factors of print strength:

the layer-layer boundary is always weakest

So, we need to make sure to strengthen that as much as possible. Let's start with the shape as it is:

Now, how can we increase the strength? Layer-layer strength is linear to area, so can reduce the number of teeth. Next, thicken the walls - two is already more than twice as strong while 4 to 5 is hefty strong.

I think you already know that in this print orientation, the tooth breaks off easily. Maybe you can try to print this thing in two parts? Use a horizontal orientation to print the saw-tooth ( with its complicated structure, using organic support might be good) and later combine with the thread?
The other things that I can suggest are:

Is it possible to make the saw-tooth base wider and thicker, although it will result in a reduced number of teeth in the circle and also make the centre hollow bore smaller? This will increase the surface area bonding the layers in the tooth, thus giving it more strength.

Try altering the printing temperature and layer height. Generally higher temp and lower layer height result in greater strength. You can check out a great 3D Printing YouTuber CNCkitchen's articles:

The Influence of Extrusion Temperature on Layer Adhesion
The Influence of Layer Height on the Strength of FDM 3D Prints

Yeah, using another material such as ABS would give better strength and heat resistivity. But it's also harder to print.

Thank you for the interesting links... good stuff.


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Ender 3 v2 with CR Touch/BLTouch moving down but not up
My Ender 3 v2 with a CR Touch/BLTouch installed is only moving down, but not up!
The display shows P Endstop when I try to move below around halfway up the gantry. What's going on, and how do I fix this?

Your CR Touch/BLTouch is not connected properly. Check the cable that runs from the mainboard to the probe on both ends. It may be slightly loose, so make sure to push both ends of the cable all the way in.


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New print job not working out well
I'm just learning and have calibrated my new Bambu Lab P1P 3D Printer. I printed the built-in scraper—amazing quality.
But I downloaded this Stiga Ping Pong Table Feet
And printed this twice to get this result:

My next print job did the same:

It seemed like the part wasn't staying on the bottom and that was messing everything up.
Ideas? lessons learned?

one thing I did was slow down the speed by 50% on the second job

Welcome to 3D printing - this kind of problem solving and the resulting success is a big part of why we do it.

Slowing down is actually very well for getting it better to stick, but bed temperature and correct setup (enough squish on the first layer) are at least as important as well.

Most probably this is caused by an adhesion problem. When the first layer doesn't stick well enough, this could be related to wrong bed temperature, incorrect distance between nozzle and bed, incorrect initial layer height and incorrect print temperature.
When the print detaches from the bed it will wander over the place creating blobs and spaghetti-like objects as shown in your images.

I think I had the "cold plate" setting that was causing the problem.

That falls under "related to wrong bed temperature" ;)


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Is there such a things as an "Optimum height above the bed" for a Resin printer, and if so, how do you calculate it?
Presuming that you are raising your print above the bed using a raft and supports, rather than printing directly on the plate.
Is there such a thing as an optimum distance above the bed to have the first layer of the model being printed, and if so, is this an arbitrary distance determined by the software\support settings that you are using (For example does using Chitubox at its default settings have an optimum height), or by the dimensions of the model, or is this something that you would calculate based on things such as the printer resolution that you are using, and thus would vary between printers even with the same model>
For example - on this random image pulled off of the internet - is there a specific reason why you would want the lowest part of the model to be at that exact height, and would making it slightly higher\lower have any real impact?

My main motivation for asking this question is that people will often angle their prints specifically so that they will require fewer vertical layers to print, and thus print faster, so it would be logical to think that they would also print their models as close to the bed as possible for the same reason, yet this doesn't seem to be the case.
Logically printing too height would increase the failure rate by having long thin supports, and would increase print times, but printing too low?


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How to move body to origin using center of body?
I have a few bodies and I want to move them together so that the center of it is moved to the origin. I don't think the bodies when selected together have the correct center I'd want as I don't think they are all symmetrical. So I would need to move them based on one of the bodies that are symmetrical.
I don't really know how to center the models the way I want with the Move tool. I'm used to Blender where doing this can be done in two mouse clicks. I've tried searching and can't find any way to do this in Fusion 360. The Move tool also doesn't let me use absolute positions, so I can't move a body to a specific position if I want to.

As can be seen here, I can't get everything to center at the origin, the green line. Near the bottom you can also see the holes aren't lined up and the hole in the middle doesn't line up either, it is too far to the left. I don't know how to line up the center of that model with the center of the other model. I've tried using the "Point to Point" but I can't select the points I would need to do it like the centers of the circles. Even then it still wouldn't be aligned vertically or in the Z-axis.

This looks more like a software question than a 3D printing question, please correct me if I am wrong.

No clue about Fusion 360, but if anyone looking for a Blender solution stumbles upon this question, in Layout, Object mode, Object->Origin->Origin to Geometry. Centers object's origin on 'center of mass' of the object.


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Cylinders have an inconsistent diameter
I'm using the new Elegoo Neptune 4 Pro printer. I have the issue with both Cura and PrusaSlicer alike (I'm a Cura user).
The issue is simple, instead of printing a perfect circle, the final print will have a diameter range of around 0.3 mm. For example, if I print a 15 mm diameter cylinder, the longest diameter will be 15 mm but the shortest will be 14.7 mm.
I measured these with my caliper and I simply turned the cylinder around in the calipers; the cylinder will push up against the calipers as it reaches the thickest part of the cylinder and then come down as it goes to the thinner part.
It's not visible to the eye; it looks like a very nice and perfectly round cylinder. But I can feel it with the calipers. The height is dead on 25 mm as designed.
However, I don't get this result from the holes inside that same print. The holes are perfect circles and measure the same diameter roughly no matter what angle I measure them (at least I believe so, measuring the holes can be a bit tougher).
Calipers are accurate and go to two decimal places for mm.
I've tried:

Tightening up the belts (a lot - caused the deviation to go from 14.7-15 mm to 14.53-14.8 mm, still roughly a 0.2-0.3 mm difference)
Bed leveling
Vase Mode
Arc Welder (even though it technically shouldn't do anything)
Axes calibration

I remeasured and found that the thickest part of every cylinder is not directly on the Y-axis, instead, it's diagonal. The bottom right and top left of the cylinder is the thickest portion while every other angle is roughly the same.
I found the same was true for the cube I made. Measuring from the bottom right to the top left resulted in 26 mm, but the bottom left to top right resulted in 25.67 mm.
Calibrated the the Y-axis (the only one that was off), issue persists. Again, this 0.3 mm deviation exists in the cubes printed as well, and always diagonally. Bottom Right to Top Left is always about 0.3 mm larger than Bottom Left to Top Right. Looked at an old calibration cube I made with my Ender 3V2 previously and the same measurements were only off by about 0.03 mm.
This is very strange, I think I may simply return this printer for a replacement.. I have no idea where to begin investigating this issue.

I took some measurements. I found that the right and left sides of the printer (which are separate pieces of aluminum) were roughly 0.2-0.3mm in difference from their distance to the aluminum center piece.
Now, without taking the entire printer apart, I can't say for certain that this measurement even matters, its possible that things aren't attached the way they seem from the outside.
However, the measurement perfectly aligns with the error margin on the prints. It also correlates to the X/Y axis misalignment, as the measurement indicates the bed X-Axis is slightly tiled up on the right side by 0.2-0.3 mm. Had it indicated it was tilted up on the left side, the print errors wouldn't have made sense as the diameter would have increased/decreased on the wrong diagonals.

They agreed to a replacement after I sent pictures of the inconsistent diameter and measurements on the printer itself. I will update on if the issue is gone on the new printer once I have it.

Have you calibrated both X and Y axes?

@agarza I heard the axes did not need to be calibrated. But after a few more tests, I believe I should. I'll try it and get back.

If you are just looking to print things that don't require precision alignment then no, calibrating the axes is not required. But you would be better off calibrating for better-quality prints.

@agarza Well, I finished calibrating and the issue remains. There's about a 0.2-0.3mm variance in the smallest and largest diameter measured on a single cylinder.

Is your hotend properly tight on its carrier plate and the plate on its axis? I.e., if you try jiggling the nozzle, does it move at all?

@towe Everything is nice and tight from the factory. Bed doesn't wiggle, hot end is firm. Also made sure the motors didn't have wiggle to them, everything was nice and solid.

If you print a larger circle - as large as your bed -, does the error stay the same (i.e. 0.3mm) or does it scale alongside the print?
The only other thing causing symptoms like that should be a slightly misaligned X vs. Y axis (them not being at exactly 90° to each other). You can try printing a "+" or "□" shape and measuring the corners to check that.

@towe Good idea, I'll try that and also check that the stand is properly aligned to the printer.

@towe I removed then reinstalled the top portion (holding the X-Axis gantry) while making sure to keep them level and the variance decreased to 0.21mm from the previous 0.3mm, showing that may very well be the problem. I also looked over the facts, and a slightly tilted X-Axis is the best explanation for these diagonal issues. I'll reinstall again later, but it's possible the holes were drilled just every so slightly wrong and is a factory defect, as it shouldnt be possible to misalign it during assembly.

Remember this isn't accurate CNC! Small variations in the 0.2/0.3 mm range are very common, there are many uncertain parameters in the positioning and extrusion (even change in filament diameter may be of influence). As already stated, whether this error is consitently scaling with the diameter of the print (hinting to changing the steps per mm) or a printing variance should be easily found by printing a larger object. you can look into skew compensation which is a default feature in Marlin firmware. Print https://www.thingiverse.com/thing:2563185 and measure diagonals.

@0scar I don't expect CNC accuracy, but this thing can't print a circle. My Ender 3V2 never had this problem. 0.2-0.3mm variations are due to plastic expansion/contraction, which is common in printing holes. But this is very different, my last Ender 3V2 printed circles and squares without randomly oscillating diameters.

3D print circles from STL data are not actual circles, they are n-gons, and as such have, with low resolution, at times massive differences between the flat-flat and peak-peak measurements.

@Trish The issue appears in all prints. I also make sure to have lots of vertices to get the smoothest cylinder possible from my print.

It's all but confirmed that the printer was defective. I got a new printer and loaded up the sample G-code it comes with, but the bed's belt snapped 10 minutes into the print (it was only finger-tight). This makes two Neptune 4 Pro printers in a row I've received with defects.
I can only imagine that their quality control is terrible or I have terrible luck. They're also not replying to my emails for the next week due to a week-long holiday. This is an entire month wasted on defective printers.
After some shenanigans, I got a new belt on it. The belt didn't snap as I thought, instead, the metal that was crimped on it failed to hold the belt and it slipped out. This was when I noticed that the Z-axis movement was very noisy. To my surprise, I find that the lead screws were entirely unlubricated.
I printed new cylinders/cubes. The measurements are inconclusive, which probably means the machine is fine. On a 15 mm cylinder I found nearly a 0.2 mm variance, diagonally. This time, the bottom left to the top right (opposite of the last printer). A 30 mm cylinder showed a definite 0.4 mm variance on the same diagonal.
I tried readjusting the X-axis, but nothing changed. I pulled out a cylinder that my old Ender 3v2 printed (25 mm diameter), the variance was <0.1 mm, a perfect circle (ignoring the Z-seam).
This printer has not been worth the time spent on it, let alone the hassle. What a shame. The printer is fast and has beautiful quality prints otherwise. But it's worthless if they can't properly align the axes at the factory.

Take a builder/carpenter/machinist square to your machine frame and double check the bed rail (y axis) is perpendicular to the gantry (x axis). The only way I can think of for this sort of distortion is if they aren't actually perpendicular and your prints are skewed diagonally.

Thank you. I believe that the x and y axes are indeed not perfectly perpendicular. I've been speaking with support for over a week now.. But once I have a new machine, I will update on if I have the same issues with the new one.


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Not leveling and not printing correctly
I have had the Ender 3 S1 for a couple of months but in the last couple of days, prints kept messing up so I decided to try to level it again. Everything moves like it is supposed to but then the light starts blinking red and it stops the leveling process. How do I fix this?

You have provided very little information for the community to be able to provide an adequate solution. Please [edit] your question to add details/information so that it isn't closed for lack of clarity.

I've read something similar on reddit and according to users it's a known issue fixed about 7 months ago. Try update the FW.

Your answer could be improved with additional supporting information. Please [edit] to add further details, such as citations or documentation, so that others can confirm that your answer is correct. You can find more information on how to write good answers in the help center.


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Is there a way to set the installed nozzle size (and installed filament color) in the Marlin firmware (or OctoPrint software)?
In addition to this question: Is there a (common) way to embed used Slicer settings inside the G-code file?.
I'm considering writing a Cura script and OctoPrint plugin because what I want seems to be not available. I suggest adding, for example, a Base64 encoded JSON array with metadata (see previously mentioned question) into each generated G-code that then can be read by the OctoPrint plugin (or, even better, understood in the Marlin firmware).
Related to that, I would want OctoPrint, or the Marlin firmware, to know the installed nozzle size. That way, my OctoPrint plugin (or the firmware) can check and match the installed nozzle size versus the nozzle size used for slicing that G-code. If mismatched, prevent the printer from printing, advise to reslice, or warn about the mismatch.
As we speak, I'm printing a physical nozzle size indicator, a physical "label" hanging on my printer. That's ridiculous and should be in the software.
I couldn't find such features in OctoPrint and Marlin documentation. This would be a great addition as it prevents errors and facilitates what some more expensive printers with "easy nozzle change" can do automatically.
First side-note: This could be easily implemented in a cross-compatible way with Prusa/Cura/Octo/Marlin, et cetera because a fundamental data structure containing the mentioned metadata (other question) is easy to implement for all without having compatibility issues.
Second side note: The same concept can also be applied to the filament color installed. If you can set the desired color in the metadata inside the G-code and the printer knows which color is installed, it can warn about mismatches.

I regularly print 0.8 mm with a 0.4 mm nozzle without a problem, so what are the errors you encounter. This question is not very clear. How many printers do you have to worry about the nozzle sizes? Maybe the following is a good read for you: Where can I change the nozzle diameter in Cura? Why is mine missing?!

I have only one printer, I don't print too regularly, so I kept forgetting which nozzle I installed, hence the physical nozzle indicator. The issue is my g-code files are saved in OctoPrint, and they don't contain easily visible information about which settings it was sliced with (for a .2, .4, .8 nozzle) and for what layer height. I sometimes want to reprint something I already sliced with another nozzle size for higher quality or for faster printing speeds. If Octo or Marlin knows what size is installed, and the g-code contains this info, too, it can be matched and warn about a mismatch.

I know how to change the nozzle diameter and layer height in Cura, and I usually end up reslicing it (meaning I lose scaling and other custom settings I've used for a particular object). My issue is with properly documenting what settings are used in a machine-readable format that can be used smartly by Octo or Marlin, the same for filament color, sliced in blue but red installed, warning (that can be ignored).

I usually make a folder structure in my OctoPrint storage  where I distinguish the prints based on the material (PLA, generic PETG, NGEN, Nylon, etc.) you could do the same for nozzle diameter, once stored in that specific location you instantly see what the code was meant for. I wonder why you change nozzles frequently I've printed more than 10 years with the (now CHT) 0.4 mm nozzle, which is capable of printing wider. I used to put the most important setting in the G-code file name, that is also a solution.

That's my solution for now https://3dprinting.stackexchange.com/questions/21563/is-there-a-common-way-to-embed-used-slicer-settings-inside-the-g-code-file but it doesn't feel like a techy solution as of 2023, there should be better options to achieve it. I change nozzles often between .4 and .6 because of the huge speed difference. A 0.6mm nozzle at 0.32 or even at 0.20 layer height is fine for most prints and gives a huge speed benefit over using 0.4mm nozzle at 0.20 layer height. But sometimes I do need more detail and switch back to the slower 0.4mm nozzle with .20/.16/.12 layer height.


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Do OctoPrint or Marlin support "ironing" and additional printing states?
Currently, OctoPrint shows a printer state such as "Printing" as shown below:

But is there is a way such as via a Cura script or OctoPrint Plugin to insert a special g-code and let OctoPrint show "State: Ironing" instead? This is especially helpful since I usually only iron my top layer, so it's only busy ironing from a specific layer.
Or does Marlin firmware already know and support states other than "stopped, paused, printing" such as ironing, tramming, leveling, heating?

Wouldn't it be better to ask this at the OctoPrint github as a feature request?

Thanks for the suggestion. I will post it there too.

Looking at the API specification, https://docs.octoprint.org/en/master/api/printer.html#retrieve-the-current-printer-state, the states are predefined. It would require rewriting the OctoPrint software to add more states, more specifically, how to detect them. Is this something you aim to answer the question?

I see. I guess I'm looking ultimately for something that is not available in OctoPrint currently. Alternatively I'm thinking to simply use M118 before and after things like leveling, heating, cooling etc. Seems status is not possible for now.


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Is there a way to reflect 'filament color change' in Cura-generated thumbnails?
I'm using the OctoPrint plugin Cura Thumbnails along with the Filament Change post-processing plugin in Cura 5.5:

I want to create multi-color thumbnails that keep into account the 'Filament Change' script that was used, for example, when printing something as shown below:

Can the use of the Filament Change script in the Create Thumbnail script be reflected so that the Create Thumbnail script can account for the color change with the desired colors, and the thumbnail will contain multiple colors, as shown in the above image?
For reference: OctoPrint-UltimakerFormatPackage: Feature Request and Ultimaker/Cura: Feature Request.


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Ability to O-ring seal SLM 3D printed part
I am thinking of 3D printing a metal part from JLC PCB's metal 3D printing service. The part will be used in a compressed air application. I need to be able to statically seal the part using an O-ring.
Will the part be smooth enough to seal with an O-ring or is there any post-processing I need to do? If I do need to post-process the part, what steps should I take?

As to how smooth the part will be, that would probably be a question for JLC PCB.

It depends
You will get a metal printed part. Typically, the process to create these is either laser sintering or laser smelting. In both applications, the powder is heated by a laser in a very small area, and by the application of heat forms a little half-sphere of connected material. By moving the work zone of the laser, the object is created in layers.
As a direct result of slight inhomogeneities in heating behavior due to particle size, the surface will have certain irregularities and a certain roughness. For example, the Manifold shown by 3dspro on their website shows this section, followed by a paragraph I will quote:

Additionally, SLM may produce parts with residual stresses and distortion in the final part, which can affect its mechanical properties and dimensional accuracy. This can be mitigated by carefully selecting process parameters and performing post-processing operations such as stress relieving or machining. SLM may also produce parts with a rough surface finish that requires additional post-processing to achieve the desired surface quality.

Depending on the tolerances you planned for and the required air tightness, you may or may not require post-processing. If you are in doubt, contact your print shop, and if you determine that you need post-processing, make sure to have extra material in the affected areas. SLM prints can be machined if you remember that your print contains possible stresses. As such, turning or milling the surfaces for the O-rings should be possible, if you are careful.


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What is the lifespan of nozzles, and does the nozzle diameter affect the lifespan?
What is the average or recommended lifespan for standard Creality printer nozzles used with non-abrasive standard PLA only? What is a proper metric for that, time used, time heated, filament meters that passed through?
Does the nozzle diameter affect the lifespan?
I know nozzles are cheap, but I'm asking because I'm thinking of writing a maintenance tracking plugin for printer parts in OctoPrint.

I will be surprised if you get an answer for this considering that regular brass nozzles that come with most printers are rather inexpensive and are easily replaced.

Nozzles don't wear out fast. You could consider a ruby nozzle or a steel one for an even longer life span. Furthermore, this has been asked before: How long is an extruder's/nozzle's life?. Also, the question contains 2 questions, the first is a duplicate the second not.

Nozzle tip wears out with meters traveled, nozzle diameter enlarges with meters printed, and speed of both depends on factors like filament color (as different pigments have different abrasiveness, white being notoriously worst), temperature of the nozzle (hotter wears out faster), temperature of the chamber (colder previous layer wears out nozzle tip faster) and many, many more. I don't think anything short of proper scientific study can give you a really useful answer.

@Mołot CNCkitchen did a study on abrasive filament - tip grinding is much more impactful than bore increase.

Print material matters more
Non-abrasive materials can leave a soft brass nozzle live for dozens of filament spools without noticeable degradation, especially if the nozzle tip is hot enough to keep it above melting point and does not scrape over cooler areas. However, abrasive filaments can eat a nozzle within just a couple gross meters. One of the worst offenders is Carbon-Fiber or Glass-Fiber infused material, requiring, for example, ruby-tipped nozzles, or glass-nozzles to withstand more than about 300 meters (~2 Gross).
Note that any filled filament is abrasive to some degree, and nobody advertises with the fact that the filament is abrasive.
Nozzle formfactor impact
A larger nozzle allows the extrusion of more plastic per time. The plastic itself, as it cools, can act as an abrasive itself. So to a degree, nozzle geometry will have an impact on the print. A flat around the nozzle orifice such as with the venerable e3D v6 nozzle design can help in keeping the orifice intact a little longer (as the nozzle has more thermal mass and can press down the filament further away from the orifice), but a thinner tip has other benefits (such as reacting faster to temperature change) at the cost of longevity in this one regard.
Nozzle diameter impact?
Typically, nozzles wear much faster and lose their tip from grinding on the printed material than that the material getting pushed through them starts to bore out the nozzle. This can be seen very well in the experiments Stefan/CNC Kitchen conducted. Also here.


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Anycubic printer gives a "hotend not heating up" error
I just bought an Anycubic 3D printer and after a few uses the screen on the printer would say "hotend not heating up".
The heat bed and hotend would not heat up all the way and would cool faster than heating up when I enabled a print.
What do I do?

Hi Dartless08, welcome to 3DPrinting.SE! Which anycubic printer did you buy?

As it is brand new, contact the seller.
If it wasn't brand new, but years into service, you could troubleshoot why it is not heating up, e.g. loose contact, bad heater element, thermistor faulty, etc..


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Can the Creality Digital Spool Holder be changed to trigger measurement externally and use the spool weight in OctoPrint?
Did anyone try to disassemble the official Creality Digital Spool Holder and to make adjustments to access to the data and to trigger measurement, for the purpose of using and showing the remaining spool weight in OctoPrint?
I like the design but you have to manually push, wait a few seconds for the spool to set to 0, then weight the spool and it will only show for a few seconds on the screen, while not being able to communicate that data anywhere.

The community is not that praising about this sensor. The weight is including the spool itself and it shuts down after 20 seconds. An interface with the main controller board would be cool though. It would require some calculations by the controller to determine the weight loss and posssibly an interface to determine the spool empty weight. I wonder if there are similar projects done by the community; does the question leave room for custom engineered solutions?

Absolutely room for custom, that was the point of my question. Preferably to hack this spool, but self build is an option too, like: I basically want to achieve this with that spool: https://github.com/dieki-n/Octoprint-Filament-Scale and https://plugins.octoprint.org/plugins/filament_scale/. What are the cons, why isn't the community praising this spool holder?


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How does Adaptive Mesh Leveling (AML) actually work?
I recently started using the new mriscoc firmware for my Creality Ender 3 V2 and it is truly performing above expectations. Even considering that Jyers UI was already a step up from the original Creality firmware.
I'm trying to understand how the new feature, that seems specific to this firmware, called Adaptive Mesh Leveling (AML) actually works in the firmware.
Below is a screenshot of how the Cura Plugin shows AML options:

I have successfully tested AML and I think it's a truly transformative and great way to do fast and more precise bed leveling, only to the relevant print areas on the bed. Also, while probing, the screen shows each probing point in real time being filled in a grid.
However, I noticed that when using the OctoPrint Bed Visualizer instructions to obtain just the mesh data using the following g-code in the OctoPrint Plugin Settings:
M155 S30  ; set temperature reporting delay, use a value longer than the time it takes for your leveling command to complete.
@BEDLEVELVISUALIZER  ; instruct plugin to start recording responses from printer.
M420 V    ; Get bed leveling mesh data.
M155 S3   ; set the temperature reporting delay back to a shorter time span.

My previously generated 5x5 of 9x9 full bed grid is no longer showing, instead the mini grid that was made on the print area is showing, as a full bed. Which makes me wonder, how does the firmware deal with AML? Is it basically tricked into using a subarea of the printer as a virtual 'new bed', the new maximum bed size being only a portion of the full bed?
Additionally would there be a way for OctoPrints Bed Visualizer plugin to even know if it deals with the full bed grid or the AML 'mini grid' and if so would it be exactly on which part of the full-bed the mini-grid was generated?

Bed Visualizer shows the mesh leveling area regardless of the bed size, that is good because it provides a good level of detail if the mesh area is very small compared to the bed size.
But it could be a useful addition if displaying the mesh area over set to the bed size were possible through a configurable option.

Nice to see you here Miguel and thanks for your answer! Welcome. You're a great addition to this site. Could you maybe explain a little bit more how you made AML work in your firmware? Does it use some kind of virtual bed size determined from the widest area from the GCODE?

Hi, Marlin implements mesh inset (margins). The Professional firmware just moves it to a next level, allowing you to change the mesh inset at runtime to leave only the interest area.


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Does additional thermal runaway in OctoPrint add anything and shouldn't it use a smart plug to kill power instead?
With the following thought in mind: 'Two eyes are better than one' does additional Thermal Runaway detection in OctoPrint add any benefit?
This OctoPrint-ThermalRunaway Plugin seems to add a basic ThermalRunaway detection in OctoPrint. I understand all the smart disclaimers he makes. Security-wise, of course, we should prefer mechanical over firmware, and firmware over external software (OctoPrint). And I think printers that don't have at least any kind of firmware runaway protection should be trashed instantly.
However, assuming you already have a printer running firmware runaway protection would this OctoPlugin add any value, 'in case firmware runaway protection' somehow fails?
Related: Firmware runaway detection as well as the mentioned 'solution' in OctoPrint are based on sending an emergency gcode to the board and performing an emergency shutdown.

Wouldn't it be better, more secure if the power was cut from the printer entirely? Eg. instead of an OctoPrint plugin sending an emergency g-code, it sending an power disable command to a smart plug (API)?Source: Octoprint-ThermalRunaway issue

It can save prints in specific situations. If you set maximum temperature lower than the one configured in the firmware, and configure the command set to cause printer to stop heating instead of stopping altogether, it is possible that plugin will stop printer from overheating before printer will panic and stop mid-print.
This, of course, does not replace other protections, but I recently lost a couple of hours of printing due to stupid error on my part, and this plugin might have prevented it.
It shouldn't be used instead of firmware protection. But I can see how it can be use to supplement it.


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Is it possible to resume a print after an M112 full shutdown?
I had a misconfiguration in OctoPrint and it kept sending M112 errors to my printer, while my printer was actually fine. As a result, I failed at least two prints, mainly on a manual layer change event. The printer paused, then timed out or something else happened and OctoPrint sent an M112 killing the printer.
I understand that usually M112 means something is seriously wrong with the printer, however, I'm certain that was not the case here and OctoPrint was incompatible with the firmware configuration I used.
In such rare cases, is it possible to disable power, enable power, have a rebooted printed that is not homed anymore or at least the firmware doesn't know it is, and resume the print from a specific layer? Because in case of filament change, the layer where it paused is exactly known. In fact, the nozzle was in park position when it failed, twice.

Yes, you can, see e.g. How to resume an unfinished project. With some editing and common sense this should be doable! You can also lower the object in Cura, print this rest piece and glue the rest pe onto the unfinished part! This could be seen as a duplicat for the referenced question.

But how would the printer know the exact XYZ positions after a full reboot / power cut and without the possibility of rehoming? I only know the exact layer number for when it stopped but not the exact XYZ positions?

It is described in the answer, a G28 XY homes the machine in X and Y for the current height of the nozzlle. If you have decent switches the exact position is known, it will print at the same location as previously. You need to define Z though in G-code. Caveat is that if halfway a layer the print stopped, you could have some iregularities at the seem, but it will always show anyways. Note that this is how many CNC machines work, homing Z is not requied. Best is to print the rest, sand the failed part and glue new piece on top.

Does  How to resume an unfinished project answer your question? If yes, then this could be closed as a duplicate. If not, could you explain why not?

How do you 'Manually position the printhead at the correct Z height' if the Z-axis is unknown and and you cannot home Z because there is still a print on the center of the bed. What I tried, is to remove the previous layers from gcode, start that gcode, but since the head was in a parking position (filament change) the height was obviously much too high. I could only guess by using Z-offset, I set it to maximum -20 and it was still just too high, so I ditched another failed print. I also need to really figure out the cause, why M112 keeps happening only with a filament change command.

Homing Z is not necessary and you know the Z height (the height is not an unknown! just count the layers of the failed print or measure the height of the print). Place the cold nozzle on top of your failed print when the steppers are not powered (or leave a paper thickness of a gap in between), alter your G-code file to home X and Y and set the Z height yourself. Now print the adapted file. It is all described in the answer of the linked question.


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Can a print test be performed to determine nozzle and filament quality?
Given that, a printer is well-maintained and calibrated.
I'm searching for a particular nozzle accuracy and filament quality test:

First, is there a specific print test that can be performed to test the quality of the nozzle alone, based on the visual results? Can that be reflected in a score of some kind, a metric reflecting the nozzle quality?
Secondly, is there a specific print test to test the filament quality, not strength properties, solely based on the visual results? Can that be reflected in a filament quality score or metric?
Lastly, are there "known good" standards that results could be compared with?

What exactly do you mean by "quality"?

Perhaps nozzle (diameter) accuracy is a better term.

Mostly a Relative measure
Assuming you have a well-known, well-printing nozzle and filament combination, then you can print a benchmark print, change one factor and then test with altered settings.
One of the most ubiquitous prints for a benchmark is Benchy. Benchy isn't so much a calibration test, but has all aspects you need in a benchmark. Overhangs, rounded corners, sharp corners, small diameter parts and sharp corners followed by longer stretches: it's all in there! and with those one gets a decent idea of print quality for other parts.
Another typical benchmark test is a cube, which has the sharp corners and stretches.
Depending on which factors you switched, you get a resulting relative quality comparison between the two prints. But you won't get a measurable metric, unless you invent a score based on artifacts.
Filament factors
Among the factors that would show up based on bad filament. The three most noticeable I can think of are:

hissing, bubbling & gaps can indicate wet filament
stretches of random underextrusion and motor skipping can indicate uneven filament diameter
sudden stalling of the extruder and no extrusion indicates a bulge on the filament

Nozzle factors
Nozzle problems generally are systemic and would show up on the whole print.

clogs from bad machining result in systematic underextrusion or no extrusion at all
too large a nozzle shows in a larger print
too small a nozzle shows in bad wall-to-wall and inter-layer adhesion and extruder skipping


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Which detection mechanisms can a filament sensor use?
Using the official Creality runout sensor, I encountered a few times that the filament entangled around something and got stuck, the printer continuing for several hours (as it didn't run out), printing mid-air aithout filament. Then I got interested in the types of filament sensors that exist such as a runout and jam sensor as those mentioned below:
The BTT filament sensor
It is supposedly able to detect both runout and jamming, which I assume uses the concept of a rotary encoder:

DIY 'super simple filament jam sensor'
From printables.com, which I assume uses simple physics, although it's unclear how this works exactly.

DIY Optical Filament Sensor
This amazing-looking optical filament sensor from thingiverse.com uses a rotary encoder.

Question
I guess that a rotary encoder would be best for this purpose because it can detect actual moving filament and potentially even exactly at which speed it is moving. However, how would it account for filament retraction or paused prints (waiting for filament color change)? Is this usually done in firmware or external control software such as OctoPrint?
I would like to understand: What different types of detection mechanisms for filament jam detection exist, and how do they work exactly? Also, which is considered most reliable and why?

This question must be impossible to answer if even with a bounty after a week nobody is even trying.

It's a great question, but I don't think jam detection is particularly common on hobbyist printers.
I know the Prusa MK3.9/MK4 and XL printers intend to add jam detection using the load cell that's built into the Nextruder, where it can detect the force between the extruder gear and the nozzle. It was promised in their promotional material, but is not implemented yet. (Today it uses the load cell to perform mesh bed levelling.) Jam detection using the load cell would have to be implemented in firmware.
Vector3D build a hotend tester using the same principles, and I feel his video nicely explains how the load cell would detect skipping and jamming: The Next Generation of Hot End Testing - YouTube.
I don't have any experience of using rotary encoders on a printer, so I cannot comment on how the data from the encoder is used to alert the user of a potential problem. I would hazard a guess that it's an OctoPrint plugin which require you to use serial printing (so OctoPrint knows how much filament is being extruded/retracted moment to moment). A quick search shows there is at least one such plugin: gmatocha/Filament-Watch-Octoprint-Plugin: Octoprint Plugin that monitors filament extrusion with a rotary encoder, the README lists the required parts and may be a good starting point if you want to build one yourself.

Very interesting plugin but the section https://github.com/gmatocha/Filament-Watch-Octoprint-Plugin#using-filament-watch---reliably does raise some valid concerns. Thank you.


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What is an appropriate layer size for the first layer?
What is considered a 'good' layer height for the first layer? Should it be relatively smaller than the other layers, or should it be considered relative to the nozzle diameter? Can the community suggest an appropriate layer height for the first layer with justification?

As most answers here: "That depends on your preference and needs"

If you prioritize bed adhesion you might want to compensate for an uneven bed surface/ level and maximize the layer height, which is around 60/75% of your nozzle width. (typical .3mm layer height for .4 nozzles). Couple this with a 200% initial layer width for optimum stickyness.
If you prioritize for quality you might just use the same layer height as the other layers, although the layer height difference is hardly ever noticeable.

I can't think of a reason to make the first layer height lower than the other layers. It would just make the bed leveling more difficult and add no detail.

It all depends on the bed flatness you can ensure. Do you have a super flat bed? Then you can use the first layer identical to other layers. You don't trust or you can't guarantee flatness? then increase the first layer thickness up to 25%.
Keep in mind that "bed flatness" depends on three elements:

intrinsic flatness (milled aluminum tooling plate or glass bed, vs rolled and wavy aluminum plate?)
rigidity of the X and (for coreXY) Y rails/rods plus the weight of the print head (do you have thin rods or a heavy print head, which gets closer to the bed when in the center? or stiff rails and lightweight head which bends only by few microns?)
availability and accuracy of the bed levelling (are you doing bed levelling? It can compensate for the previous effects if properly done).

Depending on the three factors you may need to print a thicker first layer to ensure that the printed layer is never too thin or too thick, or you may ignore the issue.
Ellis' Print Tuning Guide: First Layer Squish may help as well, after you decide which first layer thickness to use.

If the first layer is so thin the bed clearly shows through, your extruder is skipping steps unable to push enough filament, or the nozzle drags over the bed surface, you're too low.
If the cross-section profile of the extruded thread of filament is round, first layer of a print results in separate threads of filament with gaps in between or parts bulging, detached from the bed, filament doesn't form clear sharp corners where it turns 90 degrees, or becomes detached, you're too high.
The right height is when the filament is smeared somewhat flat, but still with noticeable thickness. And considering inaccuracy of printer rails, bed, drive trains, achieving such profile throughout the entire bed surface, never getting into 'too thin' or 'too thick' is what you strive for. Whether it's 0.07 or 0.13mm, doesn't really matter, what matters is it doesn't go below or above the range at any point of the bed.
A typical 0.4mm nozzle with 0.1mm first layer height is most likely to achieve this, but when in doubt, too thin will only result in dimensional inaccuracy and thinner bottom; too high will result in poor adhesion and may end up with the whole print detaching from the bed.


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Ender3 v2 on Marlin moves head while rotating button
I updated firmware on my Ender3 v2. Previously I used to have precompiled 2.0.7. Now I compiled 2.0.9 from source. Everything seems to work fine except of Move menu. Previously, I pushed the button to select axis in menu, rotated the button to set move value, and pushed again to confirm and only after confirm my head started to move. Using new firmware, I push the button to select axis, rotate the button - and head starts moving during rotation, not waiting until I push button to confirm move.
Could anyone help me out, which config parameter is responsible for this behavior? Or was it changed inside firmware?

Did you alsoupdate the firmware of the display?

Depending on the firmware you may have the option to disable live motion. Marlin has different UI for the Ender3V2 (DWIN type display), which you can choose in the configuration.h file just after the line:
// Ender-3 v2 OEM display. A DWIN display with Rotary Encoder.

You can enable the DWIN_LCD_PROUI to get the option to desactive live motion
//#define DWIN_CREALITY_LCD           // Creality UI
#define DWIN_LCD_PROUI              // Pro UI by MRiscoC

You can also look for other Marlin forks with more implemented features, for example:

Thank you. Had no idea it depends on UI. Although DWIN_LCD_PROUI still have live motion enabled (i use 2.0.x Marlin branch), I tried another options and found what i need. So it's not a promotion ;) Thanks a lot.