text:
G-code to make printer move around without actually printing
I have a Prusa i3 MK3S with the MMU on it. At my work, I'm creating a display case to advertise/show off the 3D printing we can do.  I was thinking about putting the Prusa in the display case and having it "run" for the two weeks we're in there. I was thinking it'd be cool if I could have the printer pretend to print, i.e. move the axes around, move the bed every so often, etc., but without the need to worry about if a print was messing up (it'll be in a locked cabinet I may not notice more than once a day).
I'd just slice a long print but then the Prusa will wonder where the material is. Any thoughts on how to create that custom G-code?

The simple way to do this is to slice a very long print (near maximum volume should run to 24 hours or longer, anyway), but set your slicer to nozzle temp of 0 °C and extrusion flow rate of zero.  Back the filament out of the hot end (in case you want to change before resuming actual printing), but you can leave it in the extruder and Bowden tube so everything looks "normal".  You can also optionally set the slicer to a lower print speed to draw out the movement, though this may give a distorted impression of how fast or slow the machine is.
Do test before you set up the exhibit, as it's easy to miss something when doing special settings like this...

Exactly. You can also slow your print speed to draw out the performance.

@Zeiss Ikon   so funny story, if you put a cube in prusa slicer, make it the size of the print volume, set it to 0.05 ultradetail and 90% infill, Prusa Slicer will crash.  Lol the error I got was "bla bla bla most likely ran out of RAM" which is funny given I have 32 gigs

@JosephCrozier Likely the slicer was compiled with a memory model that limits it to something like 4GB.  Try Cura, or try it on a different OS (Linux or Mac or Windows, whatever you aren't running).  Or cut down the infill (and remember to set your infill speed slower, too).

@ZeissIkon  Oh when I cut it down to 0.15 quality and 50% infill it was still like 3 days and some change, when I slowed it down after that it was fine.  Just funny.  Would have never pictured the 3d thing I'd make that would overwhelm my computer would be a cube

It's the infill -- especially if it's something other than lines or grid.  Glad it works for you, though.


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TMC2208 v1.2 stepper motor drivers not detected on SKR 1.4 turbo with RepRap firmware
I've upgraded my board to SKR1.4 Turbo with RepRap firmware. Everything works, but motors move double the request. M112 reports them as 'no-driver-detected'.
    M112
    === Diagnostics ===
    RepRapFirmware for LPC176x based Boards (biquskr_1.4) version 3.2.2_2 running on LPC176x at 120Mhz
    Used output buffers: 3 of 16 (16 max)
    === RTOS ===
    Static ram: 4956
    Dynamic Memory (RTOS Heap 5): 8232 free, 8192 never used
    Allocations: 188 Frees: 34
    Never used RAM 256, free system stack 18 words
    Tasks: NETWORK(ready,195) HEAT(blocked,243) MAIN(running,358) IDLE(ready,21)
    Owned mutexes: WiFi(NETWORK)
    === Platform ===
    Last reset 00:05:40 ago, cause: [software]
    Last software reset at 2021-07-06 23:53, reason: User, GCodes spinning, available RAM 80, slot 2
    Software reset code 0x0003 HFSR 0x00000000 CFSR 0x00000000 ICSR 0x00425000 BFAR 0xe000ed38 SP 0x00000000 Task MAIN Freestk 0 n/a
    Error status: 0x04
    Aux0 errors 0,0,0
    Supply voltage: under voltage events: 0
    Driver 0: position 37762, no-driver-detected
    Driver 1: position 37762, no-driver-detected
    Driver 2: position 37762, no-driver-detected
    Driver 3: position 0, no-driver-detected
    Driver 4: position 0
    Driver 5: position 0
    Driver 6: position 0
    Date/time: 2021-07-06 23:59:06
    Slowest loop: 9.08ms; fastest: 0.10ms
    Step timer: target 197699275 count 340845874 delta -143146599 late 0
    USBSerial connected 0
    ADC not ready 2 ADC error threshold 10 ADC Init 1
    Ints: 0; Calls 0; fast: 4294967295uS; slow 0uS adj 0 bad 0 big delta 0
    PWM Channels
    Delta -1660064855 Start -1 End -1
    === Storage ===
    Free file entries: 6
    SD card 0 detected
    SD card longest read time 1.5ms, write time 0.0ms, max retries 0
    === Move ===
    DMs created 40, maxWait 159279ms, bed compensation in use: none, comp offset 0.000
    === DDARing ===
    Scheduled moves 21, completed moves 21, hiccups 0, stepErrors 0, LaErrors 0, Underruns [0, 0, 12], CDDA state -1
    === Heat ===
    Bed heaters = 0, chamberHeaters = -1
    === GCodes ===
    Segments left: 0
    Movement lock held by null
    HTTP is idle in state(s) 0
    File is idle in state(s) 0
    USB is idle in state(s) 0
    Aux is idle in state(s) 0
    Trigger is idle in state(s) 0
    Queue is idle in state(s) 0
    Daemon is idle in state(s) 0
    Autopause is idle in state(s) 0
    Code queue is empty.
    === Network ===
    Slowest loop: 191.40ms; fastest: 0.00ms
    Responder states: HTTP(2) HTTP(0)
    HTTP sessions: 1 of 2
    - WiFi -
    Network state is active
    WiFi module is connected to access point
    Failed messages: pending 0, notready 0, noresp 0
    WiFi firmware version 1.25-01LE-D
    WiFi MAC address 74:59:09:3b:82:bd
    WiFi Vcc 2.93, reset reason Turned on by main processor
    WiFi flash size 4194304, free heap 36360
    WiFi IP address 192.168.0.200
    WiFi signal strength -80dBm, mode 802.11n, reconnections 0, sleep mode modem
    Clock register 00181001
    Socket states: 0 0

But M569 seems to be able to communicate with the drivers:
    M569 P0
    Drive 0 runs in reverse, active low enable, timing fast, mode stealthChop, ccr 0x00053, toff 3, tblank 0, tpwmthrs 2000 (4.7 mm/sec), pwmScaleSum 0, pwmScaleAuto 0, pwmOfsAuto 0, pwmGradAuto 0, pos 0

    M569 P0 D2

    M569 P0
    Drive 0 runs in reverse, active low enable, timing fast, mode spreadCycle, ccr 0x00053, toff 3, tblank 0, hstart/hend/hdec 5/0/0, pos 0

As you can see, I managed to change the setting from 'stealthChop' to 'spreadCycle'.
I also tried editing the config.g to check if the stepping is set correctly and, unfortunately, it is.
Both M350 X16 Y16 Z16 E16 I1 and M350 X256 Y256 Z256 E256 make the stepper motors run twice the distance in mm required.
I can fix this problem by setting the steps per mm from 80 to 40, but I always ran 80 and online calculators say that my steps/mm are 80.
Is there something that I missed checking? How is it possible that the motors spin twice the required?

Hi Chris and welcome to SE.3DP. +1 for an intriguing and well presented question. Hopefully someone may be able to answer your question in a few days. Good luck!

source: Stack Exchange

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

sort: votes


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Ender 3 extrusion not working properly
I got a new hotend for my Ender 3. When I start to 3D print a model, everything seems to be going well. After about 20 minutes or so the extrusion stops and the extruder motor can't push the filament through the hotend. I can usually fix the problem by pushing the filament in with my hand, but I don't know why it has such trouble pushing the filament out on its own after 20 minutes of printing.

I am printing with PETG filament, at about 200 °C. (I also got a new thermistor, and the readings on the new thermistor, could be about 20 degrees higher than they really are.)

The filament feeder knurled knob (shown below) hasn't been replaced since the day I got my 3D printer, and that may also be the culprit.

200°C is way too cold for printing PETG, especially with the Ender 3's weak extruder (ungeared, single flat hob with minimal contact with the filament) that already struggles with PETG. Probably it barely manages to keep up while the flow is low enough, but starts slipping in the extruder at some point in your print that needs higher flow, and then the torn-up surface of the filament makes it skip more and more.
Increase your temperature to 235˚C at the very least; 245˚C is what I use and I have geometry-dependent trouble with layer adhesion below that.

Yes. I tried to heat the hotend up past 200 degrees and it couldn't do it without me first keeping all fans on the hotend from running. And after it got past 225, it started smoking. white coating thermal buildup, and Also, I have had filament get so hot that it turns to a glass-like structure.

sounds like a serious temperature calibration problem.

My Ender 3 happily prints at 235 or even 245 (don't want to go hotter than that until I have my all-metal hot end).  You may need to check that your thermistor is correctly contacting your heat block.

High resistance connection to thermistor in heater block.

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


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Chitubox estimated time very away from the real time
Some time ago, I bought an Elegoo Mars 2 Pro, and I really liked the product. This is my first resin printer and I am very satisfied.
What has been bothering me a little is in relation to the slicer. When I slice an item, Chitubox shows 3 hour/20 g (consumption), but this does not converge, when I print the final result is about 40 % higher than expected, this in both cases (time and resin consumption). I understand that resin consumption can be a little more relative, but time should converge.
My settings are the defaults provided by Chitubox, changing only the resin settings I use: 8 initial layers in 50 s and 2.5 s for other layers.
Is there something I'm doing wrong? Should these values converge with reality?

It seems easy to calculate but it is not.

Due to acceleration and deceleration, the movement time hard to predict. If you take a look at Atmel source code for movement you would get clear idea.
Usually these boards contains RAMPS compatible firmware running on a separate micro controller. Any value change on this side such as movement parameters are not synchronized.
Framebuffer being used to display layer which is slow and add slight delays specially for high resolution printers.

At the end I did expect better prediction with simple math, specially considering only very few parameters adjustable on chitu. The most probably your printer timing details on chitu are not accurate.

It's quite easy to estimate "close enough".
Compared to FDM printers, movement is way more simple, and there are only 4 different types of movements during a normal print:

Lowering the print platform at the beginning of print (we can't know the starting position, so time needed cannot be really estimated)
Printing bottom layers with longer exposure times. Speeds can be set differently from normal layers.
Printing normal layers. Just like bottom, move build platform up and back down (slightly higher than last time), and do exposure with constant time.
After the print is complete, lift the print up.

My last print job was 2249 layers, of which 4 were bottom layers. As you can see, everything else pales in comparison of the time needed for "normal" layers. So we can pretty much ignore them.
But the estimate is wrong. Luckily it's very easy to fix closer to the reality. This page shows how to do it, search for "Layer Print Time Compensation"
Since print time is so predictable, it's only a single multiplier value. The easiest way to set this up is to slice a project, write down estimated time AND amount of layers. Then when the print is done record the time it actually took, open the compensation window (gear icon on the right side of Layer Print Time Compensation), and enter all the values there. It will calculate the multiplier for you. Also note that this setting is per-profile, it will be different for different exposure times, movement speeds and layer thickness.


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Use raft pattern instead of wall
This might be an odd question, as rather than being disappointed by the raft material that Cura produces, I actually love it.
It prints quickly, is sturdy yet flexible...
I was wondering whether anyone knew of a way to make the walls / base of a print use the raft patterning? Is there a strategy for using this kind of material in CAD apps, or has anyone tried implementing a plugin for Cura to turn all walls into rafts?

Hi and welcome to 3DPrinting.SE. Could you add an image of the pattern? Rafts aren't often used, but remembering the pattern I think this is already available in Cura as infill, not sure what you mean by walls. An image of what you mean might help out to make the question more clear. Thanks.

Cura, like many slicers, allows one to set the number of passes for top, bottom and sides. By setting these values to zero, your model becomes completely and only infill. The pattern selection for infill allows you to choose the design which would appeal to you and possibly match that of the raft.
I've just now imported a mostly monolithic STL file and tested the above. By varying the percentage of infill, various patterns result. Low infill percentage values make for a mostly empty print, while the higher numbers provide attractive geometric results.
Of course, one would want the original model to have sufficient wall thickness to create the objective.

excellent idea! Unfortunately my printer's motherboard recently gave up the ghost, but once I've resurrected it I'll definitely give it a go! Thanks


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Why does Cura default to printing walls so slowly?
I just noticed the other day that my Ender 3 is printing stuff a lot slower than it can, and realized when I was slicing a part that it's because the default "Wall Print Speed" is half the "Print Speed" even though "Infill Speed" is full speed.  I can enter higher speeds, of course, but then Cura puts up a little notification that "this value is normally calculated, but it has been entered instead" and offers to put it back to the calculated default -- which is half the "Print Speed."
I presume there are good reasons (print quality, underextrusion, etc.) for this -- what are they?
I guess it's relevant to note that I have a 4.2.2 mainboard and currently run Creality's version of 2.0.4-1.0.1 Marlin, the newest they offer for this board version without BLTouch.

Cura has a lot of bad defaults, but also a lot of defaults that are chosen to let you get acceptable prints out of a really bad printer, a miscalibrated printer, or a printer with bad firmware.
Printing at anything above very low speeds requires compensation for the differing pressure needed to move material through the nozzle at different flows. The printer firmware feature to do this compensation is known as "pressure advance" or "linear advance", and is absent in stock firmware on most commercially produced printers, especially older ones. Without it, you'll get bulging corners and underextruded middles of your walls. This matters most on the outer wall, which determines the dimensional accuracy and visual quality of your print; errors on the inner walls or infill will mostly be hidden and tend to even out, especially if the inner walls are printed after the outer ones so that the extrusion is constrained against the already-existing outer wall (but here's where Cura's wrong defaults come in: it defaults to printing outer wall last, which replicates the inner wall errors onto the outer wall!).
On a printer without pressure advance compensation, you can use either very low speeds (30 mm/s or preferably even lower) to get a decent outer wall, or you can use high acceleration and cornering velocity (but: most stock firmware doesn't handler cornering velocity correctly either) so that the corners aren't printed significantly slower than the rest of the wall, but at high acceleration/fast cornering you'll get ringing (ghosting) artifacts. These can also be eliminated with better tuning of your printer/firmware, but the point of Cura's defaults is giving decent output on a printer where that work hasn't been done.
If your printer has a version of Marlin (at least 2.0) with linear advance and junction deviation, or if you upgrade to that, or if you switch to Klipper, and then you tune these to match your printer, there's no reason to keep the outer wall speed low. With Klipper you can take the acceleration way up too (using input shaper to eliminate the ringing). This can give you prints many times faster than Cura's defaults. Even if you don't, you can still turn the speed and acceleration way up, but you'll get ugly and possibly structurally weak prints as a result.

My printer was new in early May 2021; it has a 4.2.2 mainboard and the most current Creality version of Marlin (2.0.1-1.0.1 is what the download says, though it comes up on screen as 1.0.1).  I'm headed toward upgrading to actual Marlin, still working on learning how to get it from downloaded source to in-printer firmware.

I haven't followed what build Creality is shipping these days. If it has linear advance and junction deviation, you can tune it to get good results at fairly high speeds already, without rebuilding.

I don't know how to do any of that stuff.  Looks like more questions to ask...  ;)

Perimeters, especially External Perimeters, are particularly sensitive to small deflections of the printhead, as well as extrusion issues from too fast of a print speed. You may be able to increase this speed for regular perimeters, however,  higher speeds may introduce more ghosting issues.

Perimeters are especially sensitive to sharp turns leaving a wavy artifact ater the turn.

Yes, that's called ghosting.

Ghosting is a function of acceleration not speed.

Speed is dictated by accelleration.


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What are the options for an insulated but still transparent door for a 3D printer enclosure?
When considering enclosures able to reach higher chamber temperatures, insulation is essential to keep the heater power low.
Typical insulation materials are not transparent: cork (fire retardant, good for the inner hot side), rock wool, styrofoam panels, aluminium insulating panels (aluminium walls with foam in between).
Still, most of the time it's preferable to have one side of the enclosure transparent, to see what is happening inside without having to use a webcam (which may not work well or which may have a reduced lifespan when operated at 60-80 °C, due to capacitors and thermal noise in the sensor).
Rock wool, styrofoam panels and cork all offer about 0.032-0.038 W/(m K) thermal conductivity. In other words, a panel which is 50 * 50 * 1 cm will require about 0.85 W per each °C of temperature increase, or 8.5 W per 10 °C. A cubic 50 * 50 * 50 cm enclosure 2 cm thick  would require 26 W to increase the inner temperature by 10 °C.
Replacing just one side with a transparent acrylic panel 3 mm thick would push the power requirement to about 190 W for every 10 °C of temperature increase, therefore finding a transparent insulation would be quite interesting.
What are the options to have a transparent, but still reasonably insulating, panel?

How about a dual pane thing? It helps in houses to get a better R value from the windows. And keep the window small as it can while allowing you to see the print progress.

Unfortunately there are very little solutions for fully transparent and thermally insulating materials. You may be able to use panels commonly used for greenhouses and hydroponics if you can accept losing full transparency and only being translucent. Another option may be to have two layers of your transparent material, with an air-gap in between, as dry and still air is a very good thermal insulator.

Two panels is of course acceptable. Are you able somehow to estimate the insulating properties based on the air gap? By the way, air is a good insulator but only when it's not moving, that's why foams have small pores. If air can move, you get vortices and a much better heat transport.

Typical glass has a thermal conductivity of 1-0.8 W/mK, Acrylic has around 0.2 W/mK, and  dry, still air comes in at about 0.025 W/mK

Obviously air inside won't be still, but it should be surely lower than acrylic alone. I could also build a double layer of acrylic, seal it and pump out air when maximum insulation is needed

Pumping air out is probably not an option due to the pressure on the outside of the glass sandwich..

It's W/m K, as in watts per meter-Kelvin. Not watts per Millikelvin. The space is crucial here: the meters is for the thickness of the panes. And note that modern windows are in the 5-10 milliwatt/meter-Kelvin area, so a magnitude or two better than acrylic.

@cmm why not? you 3D print a T support to be used as spacer at the edge, then you glue various small "+" supports in various spots between the panes, then you use silicone sealant to glue/seal the T around. You leave a hole (with O ring and cover for automatic sealing) for the vacuum pump and you are done.

@cmm you are right, half bar under pressure would already result in 10 tonnes force per square meter. Vacuuming home made double pane is not an option.

Glass. Or more specifically, insulating two or three layer window panes between which is a vacuum or low heat conductive gas.
These panels are quite effective, compared to single panes: on a  two layer sandwich, 9.5 mW/(m K) can be achieved with a Krypton filling, 5.5 mW/(m K) with Xenon. The sweet spot for avoiding too many loss from convection is usually below 10-15 mm per gas layer, depending on the gas. Three or even four glas panels can get away with much thicker total panes and avoid convection by having the gas insulator broken up into multiple layers as thin as 5 mm.
Such Mehrscheiben Isolierscheiben (insulating glazing) is often obtainable in any size from window makers and can come with a frame that contains the needed mechanisms to open or lock the box.

Acrylic is actually less thermally conductive than glass, and OP already has it on hand

I wonder whether it would be possible to have custom made double layer glass. Which would be heavy of course, but effective.

A window maker could deliver any shape and form as needed.

@craftxbox not by a magnitude if it's double pane glass with halogen.

This seems the easiest solution, I was not aware of cheap two pane glass. However 1) it will be much heavier than DIY double-pane acrylic (see my comment to the other answer); 2) thermal break, meaning that with 60 °C temperature difference (20-80 °C) it may crack, or at least the metallic coating may detach from the glass (I was also told not to put curtains too close to my new house windows, to avoid overtemperature and damage to the coating); 3) HR++ I found has about 1.3 W/(m^2 K), which is about 25 mW/(m K). I'm not sure how to reduce it by another factor of 2.5-5x, but it doesn't matter.

Higher temperature differential might warrent 3 pane, but you should discuss the setup with a window maker, who might have an idea and the knowledge to make it. Laboratory inspection windows are usually rather thick, round and in steel frames, because of the pressure in high temperature machinery.

For info: 500x700 mm triple glass weighs 10 kg, not an option. Double glass with hardened glass (to withstand more than 40 °C deltaT) costs at least about 150 €/m^2, also likely too much. I'll contact some seller to check better.

Sadly price and the best solution are enemies.

+1 - FWIW, Mehrscheiben Isolierscheiben in (British) English is called "Double glazing" (or "Triple glazing"), and "double/triple glazed windows", or just "Insulated windows". Not sure if it is the same in American English.

How about using thermally insulating transparent silicone rubber sheets?

I can't find any datasheet

Never saw double pane windows of houses? Triple panes are not impossible.

Welcome to 3D Printing SE and thank you for your contribution. Could you elaborate a bit more on your answer. As it is, it could be deleted for being a bit thin on facts and/or sources.

AKA Double glazing - double glazed windows (or triple glazed). This is the same as Trish's answer


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3D printing ESD safe/high temp parts
I am trying to develop a process to print fixtures/jigs that can withstand a convection oven temperature of 165 °C. The tricky thing is that these parts have to be considered ESD safe (surface resistivity of $10^4 - 10^11, with 10^5 - 10^7$ being optimal).
I have found tons of options where I can get one property or the other, but have had little to no luck finding any companies that are able to fulfill both requirements.
Also: the parts that I need to print need a high level of detail, (X/Y/Z accuracy of at least .005", ideally tighter) so from my experience, I have focused my efforts on resin printers, but am also open to filament printers if they can provide the accuracy I need.
If anyone has any suggestions on printers to look into or companies that I may be able to reach out to for an inquiry it would help me a ton.

Please prepare a list of materials that meet your needs. With that list, we might suggest various manufacturing methods. It may be that your can print something like PEEK or PPSU in near-net-shape, and then machine it to your tolerances (if needed).

Material selection is where I am struggling right now, from my research PEEK has a surface resistivity of about 10^16, which is considered insulative so it will not provide ESD protection against the electronics I am working with

There was a recent article on the subject here: https://3dprinting.com/3d-printing-use-cases/esd-safe-materials-for-3d-printing/

There are ESD safe nylon filaments available, but even they will be well above their glass transition (= softening and sagging under their own weight) before they get up to 165 °C.
What I'd recommend is looking for a method to resin print the parts and add your ESD protection as a post-process.  Most UV cure resins are thermoset, in that they won't soften at temperatures below where they start to break down (i.e. char) -- but few if any are conductive enough to be ESD safe.
If you don't mind a coating that needs to be reapplied regularly (possibly before each bake cycle) I've seen liquid fabric softeners used to provide a conductive coating on home built ribbon tweeters (electrostatic speakers).  Something in the formula of these liquids produces a coating that's quite a good conductor of high voltage static charges.

Thanks for the response! I hadn't thought about using a coating post-print so I will look into that to see if I can find something that will work (ideally for more than one bake cycle but if it is a simple dunk to get ESD protection then that is do-able)

Hydrophilic surfactants depend on humidity to dissipate ESD.  A hot oven usually has near 0% relative humidity.  If you use a coating, it needs to conduct independent of humidity.

Learn something every day -- I wasn't aware this stuff depended on humidity (though I was well aware humidity in a hot oven tends to be very low).


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3D printer putting scars on my prints
I just ran a 3D benchy on my Lotmaxx SC-10 3D printer and it came out fantastic. No stringing, melting, the dimensions look good, the bed adhesion is perfect, and it is identical to the 3D model. But upon closer inspection, there is this funny-looking scar on the print that I have noticed on many prints before. It was even on the very first print I did on the printer.
A picture of it:

What is causing this problem and what can I do to fix it. It only happens to one side usually only once or twice. Whenever the scar happens twice, they are on the same side but far apart from each other.

Those marks are the Z Layer seams, or the point where your printer stops moving in X/Y to move up one layer width and begin on the next layer. Unfortunately, These marks are unavoidable, but you can tune them to be less severe with your retraction settings. Most slicer software available today should have a configurable option for 'Seam Alignment' that you can set to Random in order to space these marks randomly throughout the part, though this will mildly slow down the print. More advanced slicers such as PrusaSlicer are also capable of 'Seam Painting' where you can draw on your part where seam marks are acceptable. You may also be able to reduce them by setting your slicer to print External perimeters before internal perimeters.

Random is the worst possible choice; it just distributes them all over the print rather than isolated along a single seam. What you want to do is fix them. This is usually a matter of tuning pressure advance/linear advance, speeding up your retract/unretract (so as not to dwell there a long time retracting/unretracting, oozing the whole time), and possibly adjusting slicer options about the order of wall printing.

It depends, A random distribution may be easier to mask or sand off post-processing wise. I'm not overly familiar with linear advance, so if you would like to post another answer or edit mine with the additional information feel free!

This is great advice, I am a novice at the Cura slicer but I will try to check what you all suggested and I will comment on my findings. Thanks.


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Separate Z-stepper E-steps
I have three stepper motors each with its own stepper driver. Two of those motors have the same lead screw, while the third has a ball screw.
I need to be able to set the E-steps for the ball screw differently than the two lead screws.
Can this even be done in Marlin 2.0?

Unfortunately, It does not appear that any firmware currently available supports this feature, however you can request the feature on the marlin GitHub repository

I thought as much, I am going to need to get two more lead screws.


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Z-axis rising from bed after BLTouch and homing
I have an old Ender 3 printer. I have let it sit for a year without anything to print. Nothing major has happened to it like falling or setting things on the printer.
It has an old BLTouch. I set up the BLTouch in this way:

Auto home after setting Z-offset to zero

Move Z-axis to what it thinks is zero.

Move the Z-axis down to a piece of paper until it barely grips (or up sometimes) to compensate for offset.

Copy the offset number positive or negative to the offset. It's also worth noting that my offset has been positive usually negative. Also it's nearly double what it was last time I did this.

Then I start a print which includes an auto-home.

The magic happens now as the Z-axis rides nearly 3-5 mm above the surface of the printer bed. I have no idea why.
It might also be worth noting this printer is out of shape.


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Determine screw size needed from 3MF file(s)
I have a set of 3MF files to enclose a MacroPad. They have openings for screws that go through top then PCB then into bottom, but I've been unable to figure out the dimensions of the screws needed and Google keeps trying to encourage me to design new screws, but is not returning results for determining the size and length of the screws needed.
I've tried opening the file in a number of applications (OpenSCAD, LibreCAD, etc.) and am unable to figure this out (though this could just be due to inexperience with more than changing the size of existing 3D designs).
Does anyone know if what I'm trying to do is possible, and if so, where can I read about how to do it, or if it's stunningly obvious, what size am I looking for?  If it matters I'm using Linux if it matters.
The MacroPad 3MF files are found here.

Meshmixer (free, multi-platform) supports and imports .3MF file format. There's something amiss with the file named Macro Keyboard RC Ver2.1 Top MiniCutout. It appears that the object is created from two improperly overlapped objects that have been merged. The result is a hole that isn't quite a hole:

The other files have holes that appear to be normal. Meshmixer can measure distances but that remains as an exercise to the reader, as it's a royal pain (opinion) to get results with that feature of the program.

The above image is of a different part (note image browser in screen cap) with a normal appearing hole.
The curious thing here is that Fusion 360 (free hobbyist license) also supports the file format and when imported, there is no anomaly with the pictured holes. This would imply that Meshmixer doesn't handle the format as correctly as it should. Also the measure feature of F360 is easier to use, resulting in a hole measurement of about 3.2 mm diameter.
The larger hole measures to 5.0 mm diameter.

All images created by me via respective programs with files provided by OP.

Wow, thanks. That''s very thorough and answers my question and then some.

I'm glad I could help.  If you find my response to be acceptable, please consider to click the check mark.


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Stepper motor driver dead?
I own a cheap 3D printer FLSUN Delta, which was bought 6 years ago. Several structural and other upgrades were done, such as additional frame links, a new heated bed with external MOSFET.
In the past week in the middle of a print, the printhead came crashing into a printed object and bed. I made an emergency stop and started to look for the problem. I noticed that one of the stepper motors acted weird. Below is a more detailed description and the malfunction is presented on homing example.

First I have disassembled the belt system so that stepper motors can spin freely to prevent more collisions of the printhead with frame and bed.
I have also tested all of the end stops with the M119 command and they all work perfectly.
Then I have set jog speeds to 5 mm/s in the Simplify3D's Machine Control Panel and sent G28 to home all axes. Two stepper motors did the job right as I was manually pressing the end stops, however, the third one rotated with much faster speed. This is more understandably explained with the help of the two following videos:

First one (video for the X-axis stepper motor) is showing the movement of the working stepper motor - X-axis motor. When G28 is sent, the motor starts rotating until the X end stop is pressed and is then accordingly to the Marlin re-bumped again. The clicks can be heard. The noise is coming from the second stepper motor.
Second one (video for the Y-axis stepper motor) is showing the movement of the faulty motor (or faulty driver) - Y-axis motor. When G28 is sent, it starts to spin very fast. The first two clicks are from the X-axis end stop. The first click on the X-axis end stop stops the Y-axis motor, the second one continues its rotation until it is reversed at the first press on Y-axis end stop - the re-bump takes place and it is stopped at the second click on the Y-axis end stop.

Then I have switched the X and Y axis motors and the problem moved to X-axis, so I suspect that one of the stepper motor drivers is faulty. Correct me if I am wrong.

The printer uses the MKS Mini B V1.0 control board (see picture) and Marlin V1 (output from M115) firmware (parameter MOTHERBOARD is defined as 33, RAMPS 1.3/1.4 for extruder, fan and bed).

What do you suggest to resolve the problem:

Is it possible to replace the faulty driver? I am more familiar with programming and Marlin than with actual PCBs and replacing their components.
Is it better to replace the whole board and if yes, do you suggest getting an identical one or a different one, like MKS SBASE V1.3?
Any other suggestions?

Replace the driver and move on with your life. Purchase an Heir and a spare.

You can fix this.
The current switching portion of the driver appears fine, as does the motor.
First check the improbable, but easy to fix
Although I think it is unlikely, something could have been changed in your configuration file.  It would be work a quick glance to see if there has been any obvious damage.
It is probably a board-level (not chip level) problem
Assuming the configuration is good, it is likely that there has been a (repairable) failure on the controller printed wiring board.  This could be the driver chip, pull-up resistors, traces, or (perhaps most likely) solder joints.  Given failure rates of working boards, the solder joints may be the most likely culprit.
This is my reasoning:
The driver chip is a DRV8825.  This is a "step and direction" driver chip, where the controller pulses inputs to the driver to change the position by a fixed rotation.  The DRV8825 has three input pins that define the degree of micro-stepping.  These pins are named MODE0, MODE1, and MODE2 on the schematic, and change the operation from full step, one-quarter step, one-eighth step, one-sixteenth step, and one-thirty-second step.
If there is a problem with these pins, or with the solder connections on the parts which connect with them, the motor speed will be wrong, probably by a factor of some power of two.  For reference, here is a link to the datasheet for the driver chip:  DRV8825 datasheet.
Defects in the power driver transistors cause other effects, such as no motion, jiggling, buzzing, or even reversing the direction.  Since this is not the problem you are having I think the power driver transistors are OK.
A problem with the MODE pins would cause the size of the rotational step to be wrong, which would affect the rotation speed, which is the problem you have.
You could probe those pins with the power on, looking for the voltage.  Since this is a Delta machine, the three X, Y, and Z drivers should be symmetrical.  Each of the inputs should be close to 0 V or close to 3.3 V.
If the corresponding pins are the X, Y, and Z axes are the same, then the problem is probably in the driver chip, which would require replacing the surface mount component.  Here is a link to the electronics distributor DigiKey where individual driver chips are available:  DigiKey link for DRV8825.  If the voltages are different, try re-melting the solder on all of the pins on the circuit.
[Note, I can't tell without the schematic of the board, but the 3.3 V output pin from the DRC8825 could also be poorly soldered, so check pin 15 (V3P3OUT) also.]
Good luck!
Delta machines are wonderful, and the symmetry serves you well to help diagnose this problem.


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How to restore languages to Creality CR-6 SE after firmware update?
I have been battling print issues since my purchase of a new Creality CR-6 SE. I chose to do a firmware upgrade to see if it's perhaps a patched issue. I used the Creality Download page and downloaded the zip containing the 4.5.2 mainboard firmware for CR-6 SE.
I cleared an SD card and then put the .bin found/named (CR-6SE 32bit mainboard firmware\4.5.2mainboard (C & E version/CR-6SE - V1.0.2.bin)
It loaded and then I had no text.
I tried the next bin in the same folder, the same result... continued through all of them with the same result.
It appears that the other printer functions exist, I was able to run the bed leveling processes successfully, just no text is present to label anything or to indicate when it's working.
How do I get the text to return to my display?
Bonus: I navigated to the settings menu and clicked the language menu item (using icons to navigate) and then the printer UI freezes. I have to power cycle to interact with it again.

Whenever the UI of a CR-6 doesn't function correctly after a firmware upgrade, either the firmware upgrade didn't go well or the firmware of the screen is no longer compatible with the firmware of the printer.
If you know the screen and firmware are supposed to be compatible, try updating the firmware again. There is some sort of 'is this update the same as the current version' check on it, so you may have to alternate between different firmware files (.bin) or at least different filenames. Last time it took me 3 attempts.


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What makes a new nozzle clog before I can finish the print?
I found my Ender 3 was skipping extruder steps a lot, mainly while printing infill (tri-hex at 30%), to the point I saw several layers of infill with spotty extrusion or nothing adhered at all.
When I pulled the filament, I had to use pliers to get enough grip to back it out of the hot end.
I disassembled the hot end and found melted filament in the end of the Bowden tube, though I'm not sure that indicates heat creep, because I had to dismount the fan in order to reach the heat block and nozzle with the wrenches, and then preheat to get the nozzle out (meaning the heat sink got a lot hotter than it normally would with the constant blast of its fan).
Since the nozzle was full of melted plastic as well, I simply replaced it, made sure the heat break was clear by pushing the Bowden tube through it (and removed all melted plastic from the end of the Bowden tube), then reassembled the hot end with a brand new 0.4 mm nozzle.  I then started a new print, gratified initially by the clean, even extrusion.
Until it stopped printing infill about 10 layers into the print.
At that point, I simply aborted the print and turned everything off, as I didn't have time to deal with another disassembly cycle (Sunday evening and had to be up early for work today).
What should I look for in trying to troubleshoot this issue with the nozzle or hot end clogging repeatedly?
I'm printing Amazon Basics PLA, a spool that was purchased the first week in May but only unsealed two days ago; my nozzle is set to 200 °C and the coated glass bed (now using a glue stick wash for adhesion assistance) at 55 °C.  My nozzle clearance is set by homing, jogging the Z axis up by 0.075 mm, and leveling snug on a 0.08 mm feeler gauge (set so I can barely push the feeler under the nozzle and have palpable drag when in place, done with bed and nozzle preheated); this should give clearance between 0 and .005 mm.  My first layer (standard 0.2 mm thickness) was perfect, no extruder step skipping and nice, even line width; this problem started only when the machine began to print infill -- infill prints faster than walls and top/bottom, but I'm not sure this is related to that, as I could see skipping on the walls on the second or third infill layer.  This part was printing with 3 line walls and 30% tri-hex infill.
The Bowden tube was replaced when I installed a new hot end two weeks and ten or so prints ago (which included a new nozzle, the same one that I was using until yesterday); I made the cut in the PTFE with a tubing cutter (the kind with a wheel that revolves around the tube), so I'm confident it's square, and I ensured the tubing was butted firmly on the nozzle and the lock ring installed on the push-in coupler.

Usually extrusion completely stops with heat creep.  Does you Ender 3 still not have an enclosure?  Thus, better heat sink cooling.  Your description indicates that the Bowden tube fits against the nozzle.  Have you verified that your heater-block termperature is correct with an external measurement?

No enclosure.  In normal operation, the tube coupler end of the heat sink is only warm (comparable to the heated bed temperature of 50+ C).  I have no reliable way to externally measure heat block or nozzle temp, but I can't manually extrude PLA (by pushing the filament through a disengaged extruder) until nozzle temp reads about 185 C, so I don't think it's off by a lot.  And extrusion stopping completely isn't far from where I'm at...

@PerryWebb Hmmm.  And now, after sitting for almost 24 hours, I'm getting another perfect first layer.  I wonder if it'll run five-plus hours this time, or if it'll start clogging again in a half hour or an hour?

...and it finished the print nicely.  The infill I saw before going to bed printed without a single lost extruder step (had a few in the second layer, but that cleared up on its own).  I swear, this machine is haunted (and the part I'm printing is the last of the support brackets to immobilize the relocated power supply).

That sounds like heat creep.  It sometimes happens when the extruder doesn't cool down before starting the next print.

I sounds like you are on the edge of almost heat creep if you start printing before the extruder cools off.  See if letting the extruder cool down to near room temperature solves the problem.

It occurred to me this morning that I had kept the machine preheated, bed and nozzle, for a longish time before printing that day -- I'll try switching to preheating only the bed (to ensure the glass is as warm as the thermistor reads the aluminum bed).  It seems okay when actually printing -- filament flow soaks up excess heat -- but when idle and hot, there's nothing carrying that heat out the nozzle.

Starting from a cold nozzle before *Print from TF", I've now gotten two successful prints (one 5+ hours, the other just over an hour) from the same nozzle that clogged right after being installed.

I've seen the same need to let the nozzle cool before starting a new print when printing PETG.

Got an all metal hot end on the way, should be here in the next week or two (from China) -- that should improve things some (I think).


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Building a program to convert LiDAR data directly to an STL or directly to G-code
Some people have figured out how to take raw LiDAR data and after going through multiple steps (using LAS tools, converting to digital elevation model (DEM), converting to an STL) getting an STL file that they can then slice and print.
Could you write a program that cuts out all of those intermediate steps and converts raw LiDAR data directly to an STL that can be printed? Could you even cut out the need for slicers and just go straight to a G-code file?
Is this even possible?
From 3D Printing Models derived from Lidar Data:

Retrieve Lidar Data
Process Lidar Data
Create a DSM
Export the DSM into a .STL
Process for 3D Printing
3D Print!

@Greenonline your answer was great. Your answer had to be supposition because my question was too. You've got me thinking and doing extra research, so of course it was a great answer.

TL;DR - The problem would appear to be that some of the steps require a bit of manual tinkering in order to complete them successfully - it isn't just a simple question of conversion. So, no (not currently).
Also, whilst writing this answer, it dawned on me that unless someone has actually managed to automate the whole process already, then your question may merely invite opinions (rather than factual solutions).

From the link that you provided the conversion stages seem to be:

Obtain the LAZ file from LiDAR
LAZ to LAS
LAS to DSM
DSM to STL
STL to G-code

These stages would need to be put into an automated pipeline.
Step 1
This step could be automated.
Step 2
The LAZ to LAS seems to be a straightforward conversion using  command line tools las2las, lasview and las2dem. This step probably could be automated (assuming that no manual intervention of the settings is required), as command line interfaces are easy to script (when compared with a GUI).
Step 3
This step uses one of three GUI applications and looks like some manual labour (like adjusting settings) may be required, it is not clear. If the applications suggested by the article have APIs then a CLI option of automating the process could be possible - again it is not clear just by reading the article.
Step 4
This step again uses a GUI (possibly to employ the export plugin and certainly to visualise the results) and so would appear to need some settings modifications and reiteration, to quote:

the conversion settings are something that will have to be explored via trial and error in order to figure out what is right for your dataset. In order to visualize the differences between the different settings you will have to open the .STL file into a software designed for 3D Printing.

Step 5
While the use of a slicer can be automated (assuming that you have predefined (known parameters) thresholds), it usually requires some manual intervention (at least to begin with). If you google "automate slicing" then some interesting links appear, but usually they are for batch processing of similar objects/models.
Summary
The language used in the steps above contains a lot of conditionals (may, can, could) because there are a lot of variables involved. A substantial amount of research would be required to get these elements of the pipeline to work together seamlessly. So, it is unlikely that a "point and click" solution exists where an STL file would just pop out at the end, with no manual intervention.
That said, if your LiDAR datasets were consistent (i.e. similar environments, similar objects being scanned) then you may be able to find a range of settings, for each stage, that work consistently well for a particular scenario. Then with these settings - in combination with some command line or Python scripting and/or an appropriate GUI scripting tool - you might be able to automate some, if not all, of the process.
Looking even further ahead, by using Machine Learning you may be able to train a model to learn to examine the visual feedback stages and then auto-tinker with the settings in order to get better results - however, whilst not in the realms of impossibility, it certainly is rather cutting edge (at this point in time). In a few years time though, it almost certainly will be possible.

The answer is highly depending on the programming skills of the programmer, but in theory, if all pieces of software exist, they can either be tied together in a workflow process (automated) or directly programmed into a new tool.


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Is enclosure without ventilation enough to keep VOC's and printer fumes from leaking into my room?
I am currently in the look for a 3D printer and one major issue I find it the fumes/VOCs that printing can emit. I am not planning to do ABS or similar but I've read from studies that PLA also may emit VOCs. I live in an apartment and I plan to put the printer in my office, in which I work remotely, so I spend 8+ hours per day in that room. Additionally, I'm not looking to print huge volumes, I'd rather say probably 1-2 prints per month or so.
Now, through my research I found that it's better to go with an FDM printer rather resin, as the latter not only stinks (and fumes are dangerous) but also is quite overwhelming for a beginner.
Cool, then I was looking for FDM printers with enclosure (e.g. Qidi maker or da Vinci) and others without (e.g. Creality Ender 3 V2 or Prusa).
Let's start with the enclosed printers. So, most of them advertise that they have filters on their vents but from some quick research I see lots of people complain that these are useless. In some cases some have printed an adaptor, placed it on the fan's place and use an air hose to direct the fumes outside, to a window for example. That is fine, requires some bit of work but I guess it will keep most dangerous particles away.
For enclosureless 3d printers like Ender V2, I noticed that I can buy an enclosure, like the ones that Creality advertises as fireproof. Or still I could DIY one via IKEA parts. I thought that I could enclose my printer there when I needed to print something, seal it and when done, just put it in the balcony to rest, by opening the enclosure there for the VOCs to come out and disperse in the environment. Would that work? Would that enclosure keep the VOCs from contaminating my room? Does anybody tried something similar? Would that be practical?
Would that affect the printing quality?
So in the end the question is: should I rely on an enclosure without ventilation and then put it on the balcony to rest and release the fumes?
Or should I build a DIY air filtering system to redirect the fumes outside through my window?
Which one would keep away those VOCs?

you can get rid of VOCs with a simple ionizer; my fan has one built in, but you can get stand alone units for under $20. That said, this is a cure in search of a problem with PLA.

The VOC issue is overblown. Unless you print constantly, you don't need any air treatment. Often that kind of treatment is installed by people who like DIY for the fun of it, not because it's really needed.
Characterization of volatile organic compound emissions from consumer level material extrusion 3D printers shows that dangerous chemicals may, in some cases without ventilation, exceed some of the limit concentration, but not much. So, in general, nothing goes significantly above the allowed concentrations.
With less than 2-3 prints a day the natural ventilation of the room (which you need anyway if you work there) is enough to keep VOC to a safe level (unless you watch the whole print with the nose at few cm from it).
If you want to be extra safe, use one of those flexible enclosures around the printer. It won't be super good for PLA (it gets warm inside and PLA should not be printed in a hot environment) but it will contain the VOC. When the print is done, or simply when you finish work, remove the enclosure, open slightly the window and come back in an hour or so.
That's more than enough.
If you want to filter for the fun of it, buy a HEPA filter and put an activated carbon filter after it, plus the fans to push the air through these two filters. But then you won't be in the room to work due to the noise, so I'm not sure you gained anything.

Thanks! On flexible enclosure you mean something like this? https://cdn.shopify.com/s/files/1/0046/3781/8929/products/5_bc985deb-9203-4561-9392-95d9e5a439a5_480x480.jpg?v=1611021815
I find it more of a chore rather than fun for me at least, what I want is to be on the safe side and not my hobby to affect my health. It's chemicals after all, melted and cooled in a closed environment like a room.
Would an enclosed printer be safer choice compared to a open one?

Yes that enclosure should work, unless you print PLA which should be kept cooler, but then see the other answer. An enclosed printer is like a flexible enclosure, just better sealed. The same applies.

For some filament materials an enclosure without ventilation is too warm.  You could run a hose to the outside like a cloths dryer uses and use a fan to blow the air out through it.  Then, a filtering system is unnecessary.
My understanding is a resin printing system is more complex to maintain.  You probably would only want to go that direction if you needed the special characteristics of those systems.
If you expose your printer to the variations in seasonal temperatures, you may need to adjust your printer parameters based on the different temperatures during printing.

Thanks, yeah resin printing is bit too much for me right now. Guess I have to get used to standard FDM printing and when I move to a house would probably fiddle around with that.
For FDM printing, would an enclosed printer be better choice compared to an open one? In terms of 1) printing quality 2) VOCs & fumes
FYI - since I'm a newbie I would be looking something on a budget. Plus I'm not looking to print huge items or in volumes, rather 1-2 prints per month just for fun & hobby.

Questions about print quality in an enclosure should be asked in a different question, but probably has already been answered in this site

An enclosure without ventilation would definitely not be enough to contain VOCs from my experience with ABS and HIPS (both have relatively strong smells). The fumes will simply seep out of the openings in the enclosure.
I put my 3d printer in a bathroom with an exhaust fan. The fan's outlet is IP-controllable, so I have OctoPrint run the fan every few minutes to exhaust the fumes (or constantly). It works great. When the fan is on no fumes escape. You can verify by burning some incense and seeing that the smoke flows into the bathroom from outside. Putting a facial tissue close to the door will demonstrate the suction effect also.

Neat! Did you need a plug-in for octoprint to talk to the fan?

No, I wrote a small plugin to run periodic commands and then I use a Lutron CLI tool I hacked up to send commands. See https://plugins.octoprint.org/plugins/repeatingcommand/ and https://github.com/aerickson/lutron-api#command-line-utility.


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Distinguish i3 MK3 from i3 MK3S
I have a Prusa i3 MK3 or maybe it was upgraded to a i3 MK3S.
How can I figure out?
The description of the upgrade kit talks about

the SuperPINDA (how is it different from the old one?)
a number of small changes (which?)
improved plastic parts (which parts, how are they different?)
metal clips (where to look for them?)
a number of minor changes to the extruder plastic parts (which ones, before and after?)

I'd like to figure that out without taking the printer apart.

The MK3 has 4 pins on the filament sensor, the MK3S has only 3 pins. While you need to take the extruder apart to see that, you can also have a look at the cable instead:

Matching the sensor, the MK3 has a 4 strand wire including blue and the MK3S has a 3 strand cable without blue.

Looking under the heatbed, you'll find the MK3 bearings are fixed with U-bolts while the MK3S has broader bearing clips.

You list three differences. Did you ever find out the differences mentioned in your other sub-questions, such as the minor changes to the plastic parts of the extruder?

@Greenonline: since I don't own a MK3S, I wasn't able to check for differences

On the LCD, the MK3 will show Original Prusa MK3 OK, while the MK3S/+ will show Original Prusa MK3S OK. This will only work if you have the stock firmware installed.


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Hotend temperature goes to infinity after few layers
I have a "classic" home built 3D printer, Arduino Mega, RAMPS 1.4 with Marlin 2.0.
It worked, was put in storage, and now I am trying to get it running again.
During all of the testing phases, the PID autotune, etc., the temperature of the hotend is stable.
When printing, for a few layers (4-5), the temperature is OK, despite the part fan coming on and off. However, after 3-4 mm of printing the temperature just rises and rises and rises, and after 275 °C thermal protection kicks in...
MOSFETs have additional cooling and a fan over them.
I'm out of ideas... Help!!!
My config files and G-code are here
Using PrusaSlicer.
Why do I see a temperature rise on the display? Last time I unplugged the printer and left it on USB power then gave it power again. During USB power temperature was steadily going down, as soon I plugged the main cable it resumed printing and the temperature rising again.
I did another test. 20mm above bed started printing, and got same result. I captured on video entire process Hot end to orbit. Around 2 min 30 sec the show begins.

Can you post a link to the gcode you were printing as well?

G code added to git.

How are you printing PLA at 175 C?  Or did I not look far enough in the gcode?

At 180 C. Tried first at 200, all ok. This is a new spool. Before that one I printed with PETG at 230 C. No problems. Afcore, every print ends up the same, after 2.5 mm into print head goes inferno :)

Can you try putting a shim over the Z-stop limit switch so the print starts higher, then "dry print" (no filament) to see if this still happens at the same physical height (relative to the machine frame) or after the same number of layers?

Or alternately, retract or unload filament, preheat the nozzle, and jog the Z axis up 0.1 mm at a time, then wait a minute after each jog to see if the temperature starts to take off.

Probably a thermistor cable fault (short-circuit). Does part of the cable flex about a particular point, or is it strapped tightly to other cables or structures? That can lead to cable failure, and thermistor cables do not seem to be particularly robust.

@Mick That's what my suggested tests are aimed at.  Same height relative to machine frame suggests a cable fault.

Ok. I see your point. Cabels are neatly packed, with that black mesh sleave. I will definitly try the test in hour or two. But... If it was cable problem, or termistor problem of any king, why do I see temperature rise at display? Last time I unplugged printer and left it on USB power, then gave it power again. During USB power temperature was going down, as soon I plugged main cable it resumed printing and temperature rising again.

Thermistors read a resistance related to temperature.  If the cable shorts, that resistance goes to zero (= cold, IIRC), and if the cable disconnects, it goes to infinity (= hot).  This not just jumping suggests it isn't that simple, but my tests will still narrow down whether it's related to print time/layer steps or physical height relative to the frame.

I did a test, and posted video. I edited original question.

I don't know what a "classic home-built 3D printer is", but you can troubleshoot a problem like this by tracing it backwards. Why is the hot-end heating up? Because the heater is still on. Why is the heater still on? Two possibilities: either the software is telling it to be on, or there's a hardware fault causing it to be on even though the software is telling it to be off. Let's say it's the software. Then why is the software doing that? Some possibilities: faulty sensor says it's cold, target temperature set too high, software bug. etc etc etc.

So, the problem is in fact of a hardware nature. By replacing RAMPS 1.4, the problem went away.
Arduino, firmware, G-code... everything is the same, only RAMPS was replaced.
I'm going to find a suitable MOSFET replacement.

Sounds like you have a short in your sensor or sensor circuitry.  However, if this is the case the sensed temperature is higher than the actual hotend temperature.  Does your hot end go cold when the sensed temperature takes off?  A short could also show the hotend temperature going up at an unrealistically fast rate.  This doesn't seem to be your case.

No. When temperature goes up, so is nozzle shoveling, and after error is detected, I have to wait for the head to cool of to be able to lit Z axes it leaves a big hole around nozzle...


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Ender 3 V2 bed slanted
I'm at a loss I have no idea what to do, I've tried everything I can think of. I've fixed my x-axis gantry, added silicon bed mounts, used washers, straightened out my BLTouch but still this is the result when I create a mesh:

I did recently order the solid bed mounts from TH3D, could the silicon ones I got on Amazon be the issue? Also I’m using Octoprint bed level visualizer.

Hi, welcome to 3DPrinting.SE! With straightened out my BLTouch you mean that you re-leveled the bed prior to printing, i.e. you did not mount the silicone bushings and went printing directly? Plus side is that the bed is straight! it is just tilted mainly in Y-axis direction.

Oscar is one who can help.  See https://3dprinting.stackexchange.com/questions/16604/automatic-bed-leveling-abl-with-a-sensor-bltouch-inductive-capacitive-how

@0scar what i mean is the BLTouch bracket was at a slight angle so I fixed it. And I haven’t printed yet I mounted the bushings and tried leveling. And how would I fix the y axis tilt?


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Any method that I can refer to simulate 3D scanning and flow through extruder in MATLAB?
I would like to simulate the 3D scanning process with a specific wavelength and swath width of the beam, etc. and then reproduce the image, the whole of which in MATLAB. I also want to simulate the flow of filler material through the extruder.
Can I refer to any articles or formulae?


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Anycubic Mega X slanted Z-axis
Just got a new printer (first time setting it up myself).
While trying to level it, it appeared that the left side was higher than the right on the Z-axis. When the nozzle moves left, it digs into the platform. I checked the Z-stop sensor on the right side and it appears that when the screw hits it, the motor doesn't stop like it's supposed to.
After a few tries, the screw has managed to push the lever out to the side. I'm not great with tech, anyone have suggestions?

I don't have automatice bed leveling, but Oscar has a page here: https://3dprinting.stackexchange.com/questions/16604/automatic-bed-leveling-abl-with-a-sensor-bltouch-inductive-capacitive-how

The Z-axis is usually the up/down movement, X-axis is left/right, and Y-axis is front/back. Your question sounds more like it is the X-axis, can you confirm this please?

Could you [edit] and add a photo or two in order to illustrate the issue better? Maybe of the errant screw, and the pushed out lever...


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Layer Shifting When Printing Tall Prints (Consistent Per-Model)
I have tried to print Baby Groot , but every time I print the head, there are always layer shifts like the photos below. I have printed three heads and the layer shifts happened all in the same place.

I tried to print something else that is the (more or less) same height and the layer shifting also happened.

I was thinking maybe because z-rod bent. But apparently the layer shift happened in different height.

What is my problem and how to solve this  ? I am using Ender 3 with BLTouch.

What I have done:

Using lowest hotend temperature 170 °C
Using highest hotend temperature 220 °C
No wobble in extruder (x-axis)
No wobble in gantry (x-axis)
No wobble in bed (y-axis)
No wobble in z-rod (z-axis)
Bed levelling to my perfect
Shorten and slower the retraction, from 8 mm and 70 mm/s to 6 mm and 50 mm/s
Enabling and disabling retraction
Enabling and disabling z-hop (z-lift in PrusaSlicer)
Formatted the micro SD card
I have tried using Cura as well. I thought maybe different slicer will result differently.
Position the z-offset from -2.20 mm to -2.15 mm
Position the z-offset from -2.15 mm to -2.10 mm
Printing a bigger round, vase

All of those don't solve this issue. Then I realized that while my z motor rotates there were some occasions where the rod wasn't rotates. I changed the hex bolts and tighten them up properly to solve this issue.

Layer shifting has two basic causes: the partially printed part moves or flexes, or the bed or Y carriage (almost always -- they seem rather uncommon on the X axis) skips one or more steps in one direction or the other.
Permanent layer shifts -- that is, where the entire print above the shift is and remains shifted -- are more likely to be the latter; temporary shifts (where the shift creates a bulge or groove, and then layers above that section are back in line with those below) are more likely due to part movement.
In your case, you appear to have temporary shifts.  Those on the Groot head seem (in the photos) to line up with heights at which some of the peaks on the head end; they might be a result of changes in the nozzle interaction with a print that's becoming tall enough to flex as the path changes due to those sections finishing.  The ones on the pink block look more like temporary overextrusion, but since we can't see the opposite side of whatever that is, I can't say for certain that they aren't the same thing.
One thing you might try is reslicing both of those objects with Z-hop enabled.  That will reduce nozzle dragging over earlier parts of the current layer, which can flex the part (or temporarily block the nozzle, causing pressure buildup that will lead to momentary overextrusion).
To save time, you might look for whether you have any objects that exhibit this without as many hours of printing time (and tens of grams of filament) already spent -- perhaps you can sink Groot into the virtual bed in your slicer, so as to print him only from the eyes up (or even higher) -- though that might reduce flex enough that finishing the peaks on his head won't result in a significant change.

I always use 0.4 mm z-lift (z-hop in PrusaSlicer). And the pink block has the opposite side more or less the same. Is this more into a bent z-rod or a wobble bed? I feel you are more inclined toward wobble y-axis than z-axis.

For a screw-fed Z axis, that has correctly adjusted gantry rollers, the Z screw won't do much of anything to the Y axis position.  This has to be the bed being out of position.

Hey there, I have tried to tighten the bed to no wobble. Using this video https://www.youtube.com/watch?v=liJ0DbuMeZ4 as a guide. But the problem is still persist.

That puts us back to nozzle/print interaction.

Hey there... I just found out in case of the pink vase, it is happened due to the nozzle dragging the the shell/perimeter! My question become, why is it happening on specific height consistently?

I'm going to guess that print doesn't have the Z-lift, and the nozzle drag happens when the nozzle runs back over already printed material from the same layer; it happens at the same height because that's the height at which the combination of Y-axis acceleration and print flex put the part in the way.  There'll be a change in bed acceleration on Groot when each peak finishes, too -- which might be why you have the artifacts at those heights.

Zeiss Ikon's answer is good - but just in case that doesn't solve it, have you printed larger / longer prints before? There's a well known problem with the Ender 3's 4.2.2 motherboard that causes layer shifts as it overheats on longer prints. You can try elevating the printer and putting a fan underneath to see if that changes anything. (I had that problem and it drove me nuts until I got a 4.2.7 motherboard)

https://www.reddit.com/r/ender3v2/comments/lmf1v2/an_faq_on_layer_shifts_and_mainboards/
https://www.reddit.com/r/ender3v2/comments/kn8u72/layer_shift_investigation_data_and_video/
https://www.reddit.com/r/ender3v2/comments/kxeikz/as_promised_thermal_camera_captures_of_a_layer/

However, I do see some other layer issues on the head further down the print. I would probably loosen and readjust all the gantries again, check all the belt tensions, do another bed level (you changed out the stock springs with the yellow ones right?). After hours of use, not uncommon for there to be a hiccup, maybe a piece of plastic / dust stuck in a track.
If you've double checked and adjusted all the gantry's and none are loose or too tight, look at your table the printer sits on. If possible, put the printer on something really heavy (slab of concrete, thick wood) with a little padding underneath that heavy surface. Put a half glass of water on the top most surface (not on the printer) to see if the table is vibrating while printing (water should be still the entire time). It could be the table is moving a little as the printer is printing - with fractions of mm's it doesn't take too much.

Hmm.  This makes me glad I've got a 4.2.7 mainboard on hand, I can swap it in an hour or so if I decide the 4.2.2 that came with the printer is causing trouble...

"Zeiss Ikon's answer is good - but just in case that doesn't solve it, have you printed larger / longer prints before?" ---> I printed Baby Groot's head couple months ago just fine. But that was before I have done many upgrades to my Ender 3. This is the first tall print since those upgrades.
I have replaced the board with the 32 bit one. It is "BigTreeTech SKR Mini E3 Version 32 Bit Mainboard with TMC2209". And for the firmware, I am using Marlin 2.0.7.2 with BLTouch Z-Homing. Do you think this cause the problem?
I am very very sure I have properly tighten all belts for x and y.

The prints in my case were printing for about 12-15 hours before the layer shifts started. It's easy to test though - try to raise the printer, take off the motherboard cover, put a small fan underneath to keep it cool See if it does it.

The fact that they're happening around the same height makes me wonder. Did you try my glass of water trick to see if the table is moving? Maybe when the Z gantry gets high it shakes more.
Also, check the squareness of your Z extrusions. It could have shifted, which might also cause layer shifts.

These are (at least almost certainly) not layer shifts. A layer shift is when the physical toolhead position becomes inconsistent with the logical one because a stepper motor missed a step or the bed surface shifted or something else went wrong. It's possible for them to reverse if the same happens in the opposite direction at a later layer, but very unlikely.
What you have seems to be geometry-dependent inconsistent extrusion. If you look at the slicer output in an analyzer, you probably have some geometry difference in terms of number of components, travel moves needed, etc. at the affected layers, causing more or less material to be oozed/lost in the model's interior, thereby producing more of less extrusion thickness in the walls that follow, relative to other layers.
While there are probably other ways to reduce the impact, the right way to fix this is find the cause of the oozing and stop it. It's almost surely unretracted travel moves inside the model interior, which Cura calls "combing"; I don't know the Prusaslicer terminology for it. You can either turn it off (which will make your print a lot slower and might harm quality in some ways) or set "Max Comb Distance With No Retract" to something very small, like 1 mm. This will create a lot of additional retractions, and you need to make sure your retraction settings are right (in terms of distance and speed) not to make the problem worse - you can also ooze material while waiting around for a slow retraction to happen. Doing a retraction tuning tower can help you get them right if you don't have them right already. On an Ender 3 you should be able to set the retraction (and unretraction) speed to at least 100 mm/s, with distance somewhere around 4.0-6.5.
For readers using Cura, also be sure to set the "Minimum Extrusion Distance Window" option to 0. Otherwise Cura will start skipping retractions again once there are too many of them, which will bring the problem right back, possibly far worse since it might skip them even in the places they matter most. I don't think Prusaslicer has such a problem but I'm not sure.

Does combing (crossing parameter) be taken care of if I am printing in vase mode?


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What temperature should I bake PLA prints at to increase strength?
I recall seeing that it's possible to "bake" or "anneal" or even "remelt" PLA prints to strengthen them.  As I understand it, the main effect is improving layer adhesion, which is the main source of weakness in tension in the original Z-axis direction.
Yes, I can print with a hotter nozzle (up to a point) to increase layer adhesion, print with a larger nozzle orifice, print with increased layer height, print slower -- but at a minimum those require reslicing, and affect print appearance (hotter nozzle causes stringing, thicker layers are more visible, etc.).
Baking a print does none of that, as long as it's supported (often done by bedding it in salt).
Question is, how hot?  I presume I don't want to go all the way to printing temperature of 180-220 °C, but the plastic transition level of roundly 50 °C isn't hot enough for this.

source for improved layer adhesion? I remember annealing as a way to improve temperature resistance, mostly.

@FarO At least one of the articles linked in the answer below talks about layer adhesion, and that was the subject of the video (of which I've only seen the thumbnail) that I was recalling when I wrote the question.  Makes sense that if the material softens enough to recrystallize, the layers will sinter together if they weren't already well joined.

I've only annealed PEEK personally, but a quick search returns varying recommendations:

All3DP
recommends 1 hour at 70 °C.

X3D
recommends 1 hour at 110 °C.

Matterhackers
recommends 10 minutes at 105 °C for Tough PLA or HTPLA.

A post on
Reddit
recommends "a few hours" at 110 °C.

I'd do a test suite with pieces at 70 °, 90 °, and 110 °C for an hour each and test/compare.
Be mindful of any chemicals that might be released.

CNC Kitchen has a series of videos covering research on this topic, ending up with

 using salt. The oven temperature used for PLA was 200˚C reaching 190˚C at the core of the salt. Lower temperatures (especially without support) are of much more questionable value.
From my experience, I believe that similar results might be achievable just by improving the printing process, without any annealing. This is because a lot of the weakness along layer lines seems to be caused by inconsistent extrusion (largely due to oozing in the model interior) and marring of the layer by combing travel over it before the next layer can be laid. With these issues solved, my prints got a lot stronger. So if your goal is just to fix a practical part strength problem, it may be worthwhile to see if you can improve things here before trying an elaborate annealing process (which necessarily requires 100% infill as well as a lot of messy postprocessing work).


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PC-ABS poor layer adhesion
I recently started printing Polymaker's PC-ABS blend on my modified Ender 3 v2. The print quality is good but the layer adhesion is pretty bad.
The layers aren't delaminating while printing but I can snap the chimney off of Benchys just with my fingers. Print quality and layer adhesion are the same on Benchys with and without an enclosure.
My enclosure gets to around 65 °C air temperature, but Polymaker recommends 90 °C. I doubt my Ender would function at those temperatures.
Cura settings are as follows:

270 °C 0.4 mm brass nozzle
105 °C bed
0.2 mm layer height
0.4 mm line width
combing off
cooling off
15s minimum layer time
Lift Head on
4 mm retraction at 33 mm/s
30-22.5 mm/s print speed
3 walls
5 top and bottom layers
20 % lines infill

I have already tried a wider line width, and I don't think going any hotter or slower would help. What could I try in order to improve the layer adhesion?

Try using some halogen bulbs (for example car healights) with a heat resistant shiny reflector to increase the temperature of the printed part without having to increase the air temperature. You can easily reach 90 °C with 4 bulbs (one per corner, pointed to the center).
And until you find a good print settings, I would still stick with 110-120% line width.
Also, there are reports of underestimated printing temperature. If you can, go try 280-290 °C.

The temperature may already be a bit high. I kept the filament in a drybox but if it's extruded too slowly it will bubble and pop. This tells me the polymer is being destroyed when exposed to 270 °C for too long. If I go any slower or hotter this may become an issue. I'm not sure my printer would survive 90 °C. I may try using a draft shield in addition to the enclosure which might help keep the temperature around the part hot enough.

If it bubbles and pops it's not excessive temperature, it's humidity! ABS has typically no problems, but PC has A LOT. Put that spool in the oven at 70 °C for about three hours, then keep it in a dry box. Be sure that the silica is not depleted already! dry the silica by putting it in the oven for 3 hours at 120 °C. And keep a reliable humidity sensor in the dry box to know when it's time to dry the silica again. I use a Xiaomi temperature/humidity sensor which works extremely well. After drying I reach 1%, after three months it's back to 10% and I dry it again.

But true, the Ender 3 cannot get higher than 270 °C.

It doesn't bubble and pop when extruded at a normal rate, only when extruded very slowly or when oozing. It comes out very rough and brittle and almost looks carbonized. The smell is also terrible.


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Thingiverse dealer button text block
I’ve been using Thingiverse pretty heavily since I started printing, and I frequently come across the same text block in unrelated models. Am I missing the joke or a hidden meaning in the frequent reuse of the following content?

Designed up this dealer button to use in home games or have just as something laying around for any poker fan. It was inspired by a dealer button in Pokerstars VR.
Printing:
Ring - Infil to add weight, supports needed for spade inset. Letter embossing doesn't need it.
Spade - Infil to add weight, no supports
Letters - Print flat, already scaled to fit nicely in the embossing
Star - Infil to add weight.
Full print with 4x4x4 walls/top/bottom and 38% infil came to about 48g in weight.
Glue in lettering and spade. Star may need minor sanding but should push fit into the space tightly and not need anything else to secure it.

Here is an example of what I mean: Voronoi bear. Just curious if anyone knows why that’s used as a pseudo default description, or if I should avoid those files for any reason I’m unaware of.
Here’s another example: cats

At first glance, I'd suggest someone pasted a block of text and submit it without due care. If this is appearing in other models, it's more difficult to make a conclusion. Is it the same user making these model-unrelated posts?

I see it across users, concepts, everywhere it’s weird. You can leave that section blank so it seems to be an intentional choice.

Maybe it's the result of some database corruption on their site? The site is basically unmaintained and has a lot of issues so it wouldn't surprise me if something like that happened.

I’m voting to close this question because it's about default text (or a bug) on a website.

I’m voting to close this question because it's likely better suited for chat and otherwise unrelated to 3d printing.

The "dealer button" text is the default text that Thingiverse inserts when you create a new Thing entry.  If you get in a hurry and hit "Publish Thing" before you edit that, it'll go up for everyone to see with the "dealer button" default text still in place.  Many times, when you see that, you'll also see the defaults still in place for machine specs, filament type, etc.
In other words, it's just a user error, especially prevalent on "quickie" uploads that aren't intended for a wide audience or long term preservation.  Based on comments, this may also be a relatively recent change at Thingiverse; I've only uploaded designs there over the past few months, and I've seen it every time over that time frame (since about April 2021).

That was not the case when I last uploaded something to Thingiverse though, but I can reproduce it now. What an odd "feature".

@towe I agree, I guess someone decided obviously wrong text is better than a blank field (perhaps a blank field messes with their database some way).

Probably, but I'd have used the Lorem Ipsum or some "DESCRIBE YOUR CREATION HERE". Weird.

@towe Again, I agree -- but as noted elsewhere, Thingiverse is basically unmaintained...

Consider this example:
https://www.thingiverse.com/thing:4888256
The text entered by the author is visible above the seemingly random text you mentioned in your question.
Seeing how Thingiverse is a Makerbot product, it's likely that they've messed up their database somehow.


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Converting .par files to STL
I am using SolidEdge to create 3D models in .par files and right now I have over 30 files and I need to create STL files to print them in 3D printer using GrabCad
Is there a way to convert all those files in one go instead of converting them one by one by exporting them to STL inside SolidEdge

Welcome to Stack Exchange 3D Printing! Is this what you are looking for? or is this a different problem?

No, in my case I have 30 part files and 1 assembly file and I need to convert all the part files into their respective STLs in one go

Perhaps this helps? https://blogs.sw.siemens.com/solidedge/translating-solid-edge-files-from-the-command-line/

Yes, there are several software options that can help you convert your .par files to STL files in bulk. Some popular options include MeshLab, Netfabb, and 3D-Tool. These software programs allow you to batch convert your files, saving you time and effort. Additionally, GrabCAD also has a feature called the "Batch Print" tool that allows you to select multiple files and convert them to STL at once. You can access this feature by going to File > Batch Print. I hope this helps!


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Layer splitting in same place
I am getting layer splits that always happen in the same place like these:

Interestingly enough, when I do multiple prints on one plate, sometimes some prints get split and others don’t. I don’t think this is a slicer settings problem or moist filament because it only ever happens at one specific place. The rest of the printed item(s) is fine.
I also don’t have warping at the edges of the upper split layer that signifies slicer setting problems. Another interesting note is that there seems to be little evenly spaced pulsating dots along each side of the split (might be hard to see in the photos).
I have checked the Z-axis for anything that has gone loose, greased the lead screws, adjusted temp, but nothing seems to help.
Edit:
I recall having similar problems once with Colorfabb Economy PETG on a different printer (Artillery SWX1) but I can only recall it from memory, no physical prints to prove it so it might have been something else.
However that does lead me to think that it may in fact be something with the slicer if it happened on separate printers printing different parts, but maybe not the direct slicer settings, rather the geometry of the model causing it like r.. github said.
Filament: Inkstation black PLA
Printer: Creality Ender 3 with added BLTouch.

Can you add the material you're using to your question? I suspect it might be PETG.

From your description and particularly the photos, the source of your layer splitting is an extrusion problem at the particular location, likely an indirect result of the geometry (making it mostly repeatable when the same geometry is printed again). Some possible causes for this include:

Too much material lost to oozing in model interior just prior to this extrusion, as a result of unretracted travel (combing).
Previous layer marred by unretracted nozzle motion over already-printed material. This tends to make the "pulsating dots" pattern you noted.
Extrusion jam due to heat creep or trying to unretract after the retracted material had too much time to cool due to long/slow travel.
Higher speed being achievable on these layers due to less constraint by acceleration/deceleration, reaching a speed faster than what you can actually extrude with your extruder, hotend, and temperature settings.

I would look at the slicing output in your slicer and see if you noticed anything different about the layers where it's happening.


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Why is Cura printing vases much slower than the printer can go?
I have been trying to tune a new filament, on my CR-10 V2, by printing vases, but Cura won't let me print the vases any faster than 10-15 mm/s even when I input all the print speeds to about 65 mm/s. This problem only occurs when I try to print with a single parameter/wall and no matter what I do Cura doesn't print it any faster.
Does anyone know if there is a feature that forces it to print slower than it's being told to, or if this problem is a result of some kind of protective feature and if it can be overridden?

Minimum Layer Time. By default it's 5 seconds, and some printer profiles have it much higher, e.g. 10 seconds. This is to allow sufficient time for the previous layer to cool before laying down the next layer, but it's way too high. Make sure you have good cooling (possibly blowing a large room fan on the print volume if needed) and you can turn it down significantly. This is unlikely to work for very tiny details, where 3-4 is about the lowest you can safely go, but in a vase spread out over a large area it should be practical to cool it even with fast printing.


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Ender 3 Microswiss Print Quality Decrease
My Ender 3 was working AMAZING. I decided to buy it a Microswiss All-Metal Hotend. I called the company I bought the printer from, and they sent a technician to install it for me. Once he installed it and left, I started a print on it. The print quality was TERRIBLE. There was stringing everywhere, and the print quality was overall worse. I releveled the bed and tried tuning my slicer settings. I am using PrusaSlicer's default Ender 3 profile with just a few adjustments.
Start G-code
G90 ; use absolute coordinates
M83 ; extruder relative mode
M104 S[first_layer_temperature] ; set extruder temp
M140 S[first_layer_bed_temperature] ; set bed temp
M190 S[first_layer_bed_temperature] ; wait for bed temp
M109 S[first_layer_temperature] ; wait for extruder temp
G28 ; home all
G1 Z2 F240
G1 X2 Y10 F3000
G1 Z0.28 F240
G92 E0
G1 Y190 E15 F1500 ; intro line
G1 X2.3 F5000
G92 E0
G1 Y10 E15 F1200 ; intro line
G92 E0

My retraction settings:

Stringing can be caused by a variety of reasons.But as you stated, you changed the hotend assembly,I would recommend you to print a temperature tower to see if the printing temperature is too high especially when the thermistor is also replaced.It could have -10~+10 degrees variance between the actual nozzle temp and what is on the screen.

Extrusion temperature deals with a trade off.  Lowering the temperature reduces stringing, but also reduces layer adhesion.

What material are you printing? If PLA, then you did not upgrade but sadly downgraded the printer. You need to lower the printing temperature and see if that works. All metal hot ends are for high temperature filaments.

@0scar thanks.  I only print in PLA.  What do I Do?

Have you done a PID tune?


text:
Ender 3 Upgraded to All Metal Hot End -- Heat Creep?
I was having heat creep related hot end clogs leading to skipped layers or plain old air printing (with extruder stepper skipping).  Since I'd just received the all metal hot end I ordered a while back (Chinese knock-off, verified 2 mm heat break bore), I installed that and tried a print without changing settings.
Amazon Basics PLA, 200 °C at 0.4 mm nozzle, 50 mm/s (which gives walls and first layer at 25 mm/s), and 30% tri-hex infill -- and instead of clogging an hour an a half into the print, the new setup clogged after only about half an hour.
There is little retraction in this part -- every layer is continuous (that is, there are no travels between sections, only between infill lines and after layer end, it's a simple extruded shape from the first layer to the last), so I wouldn't expect excessive retraction to be a major issue.
Is this likely to be due to printing with the same settings I had for the original hot end?  If so, what should I change (retraction, obviously, but temperature, print speed, etc.?).
EDIT: Reinstalling the previous (stock type) hot end after clearing filament material from the heat break has restored normal-seeming operation, at least when starting a print from cold.  Parts are on the way to apply the PTFE fix.

Extruder cooling fan isn't powerful enough? Have you changed your hotend fan?

@FrontENG Still running the stock fan for both heat sink and part cooling.

This kind of all metal hotend is not recommended for just PLA.It's not an "upgrade".The metal throat tube actually make it easier for heat to creep up unless you install a more powerful fan. 0scar explains this in his answer https://3dprinting.stackexchange.com/a/11979/19888

And did you try the PTFE fix for creality MK8 hotend?There could be a gap between nozzle and ptfe tube which increases drag and causes "clog" looks like heatcreep

@FrontENG Why does everyone assume that someone who's had a printer for two months has read every word on every source about it?  " the PTFE fix" is what?  I'm pretty confident that I didn't have a gap on the old hot end; I installed the Bowden tube cold, and got a pretty solid bottom out when I did.  The tube was cut with a tubing cutter, so I'm confident the end is square.

@FrontENG Okay, that's the captive, high temperature PTFE mod, with spacer under the coupler fitting.  Nope, haven't tried it.  Sounds like you're saying I should.

All metal hot ends conduct more heat to the filament in the heatbreak.  Thus, it's easier to get heat creep.

@PerryWebb Hence why the heat break is made of titanium or stainless (both relatively poor heat conductors), and often has a reduced diameter neck between the heat block and heat sink, to control this heat transfer.  Apparently, it's not enough.  Or the tube should be chromed inside or coated with boron nitride or similar to prevent adhesion...

Yes, but if the heatbreak is lined with PTFE or has the PTFE bowden tube go all the way to the nozzle, the filament is even better isolated.

Maybe replace the PTFE in the heatbreak with high-fire glazed ceramic.

But then we're limited by the breakdown temperature of PTFE.  I've ordered a Capricorn tube kit, and I'll find or make a spacer to recreate the "PTFE fix" in one of my lined hot ends, then clean up the all metal one and save it for high temperature.  At least I didn't pay name brand price...

@PerryWebb "Maybe replace the PTFE in the heatbreak with high-fire glazed ceramic."  Hmm.  Porcelain tube, 2mm ID, 4 mm OD, high glaze...  Sounds expensive...

Change the heaterblock and heatsink to copper, then you would have an extruder capable of very high temperature.  But, too expensive unless you really need it for the material being printed.   Back from chasing the rabbit, even a poor thermal conducting metal conducts much more than PTFE.

Maybe a Pyrex or quartz tube would work and be less expensive.

Print faster, increase cooling. What is your speed?

No settings were changed (in fact, I used a .gcode file already on my microSD for the parts I was printing); full speed at Cura default 50 mm/s, walls and first layer at 25 mm/s.  Layer height 0.28 mm, 30% tri-hex infill.

Anyway the Ender 3 should not have heat creep in its standard configuration. Yes all-metal may worsen it, but if you have it with the stock hotend, something else may be wrong. I had heat creep with PLA in the past, I solved it by adding a fan to cool the filament before it enters the extruder+hotend, however it was direct drive and easy to do. Try to cool the bowden tube near the hotend and see... maybe the air is too warm

@FarO As others have suggested, this might be due to the Bowden tube backing up under pressure.  I haven't had a clog since reinstalling the stock type hot end, and I'll be installing the "PTFE fix" (captive high temp PTFE inside the heat break) this weekend.

As suggested in comments, I've installed Luke Hatfield's captive PTFE tube fix using high temperature Capricorn PTFE tube inside the heat break, and this seems to have solved the problem, while accomplishing the main thing I wanted an all metal hot end for: allowing higher print temperatures for filaments that require it.
In my case, I had to modify the classic procedure a bit; careful measurement of my heat sink required printing a custom "washer" with top end diameter of 8 mm, bottom (against the heat break) diameter of 5 mm, 4 mm taper length, 1 mm thick non-tapered top extension (so the coupler could compress the washer into place); I drafted a 2.25 mm bore (after an initial prototype at 2.1 mm wouldn't pass filament with marks from the extruder teeth; there's probably some shrinkage in the printing process) and an entry cone of 3.125 mm diameter, tapering to bore diameter after the first 3 mm.
I cut a piece of Capricorn PTFE tube 1 mm longer than the heat break; assembled heat break to heat sink (to ensure it was bottomed against the shoulder in the bore), then screwed heat break into the heat block to set depth, ensuring that the nozzle would tighten against the heat break before bottoming the hex against the heat block.  Hot tightening the nozzle, followed by tightening the coupler, gave about 3% compression of the captive Capricorn tube, ensuring a good seal against the nozzle.
I kept the stock, translucent PTFE for the Bowden tube, so I can see the filament (at least as a shadow) when I load it, but where it matters, I now have captive, compression sealed PTFE that's rated up to 300 °C -- and this has so far worked perfectly for a number of prints.


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PLA filament becomes brittle inside PTFE tube
I know that it's said the PLA becomes brittle when kept in a humid environment, but my case is slightly weirder:
I have rolls of 1.75 mm PLA that I bought years ago and they are fine. But if I leave my spool fed inside the PTFE (Teflon) tube of my 3D printer, that part that is inside the PTFE tube, and only that part, gets brittle. The filament spool is always (even when stored) in open air.
Is it still the humidity that somehow is better kept inside the tube, or is there a weird reaction of PLA with PTFE?

I have this exact problem, and mine is in a dry box.

I don't have a dry box. Filament spool is always (even when stored) in open air.

I have the exact same problem with a PLA roll that is 3 years old. Breaks in the PTFE tube, but only if it has beend inside the tube for 1-2 days, the rest of the rest of the roll prints just fine. Any update on this?

I have this exact problem as well. I am feeding filament from the dry box through the tube into the top of the hot end. After approximately 2 days I would notice that the filament is broken somewhere close to the hot end. I don't believe that it's just humidity.
I suspect that the filament being brittle and being made to conform to the PTFE tube's shape, having been recently on a spool, is causing the breaks.
As a result, I'm going to write a small script that will heat the hot end and eject 200 mm of filament every so often.
EDIT: Whilst the script works, the filament would just break somewhere else lower down in the tube. Therefore the amount of filament that would need to be extruded periodically would be just wasteful. A better solution would be to unload the filament, either manually or automatically (somehow).

I don't have a dry box. The filament in the open air doen;t get brittle, wile the one in the PTFE tube does ...

Did your script work? If so, can you post it in the answer..?

@Greenonline, no because the filament would just break somewhere else further down in the tube. It's not a practical solution. I suspect that I would have to have some sort of "unload" mechanism, to retract the filament into the dry box.

That's a shame. Thanks for the update though :-) However, does that mean that your answer isn't really a solution (apart from your suspicion of the brittle filament)..? BTW, could you [edit] your answer and add that last bit of info in your comment to it? Thanks.

I'm having the exact same problem - it is enough to leave the filament inside the PTFE tube for an overnight and the next day the filament inside the tube is so brittle that I'm not even able to eject the filament without disconnecting the tube and getting out all small pieces of filament manually... but from my experience, it affects only cheap PLA filaments (like Creality ST-PLA) - I never had such issue with other types of filaments (ASA, PETG) or higher-quality brands of PLA (e.g Fillamentum, Filament PM...).
BTW - there is a video on YouTube demonstrating the same issue:

Hi Dominik and welcome to SE.3D Printing. SE websites are driven by questions and answers, your answer is more a forum style "Me too" comment to another question where you ask for help to start a discussion. This is not what the answer section should be used for. Please read the [help], accessible through the button with the question mark at the top right menu. Please take the [about] and also have a look at the questions and answers to understand how SE works.

Apologies for the standard comment above. However, your post doesn't really answer the question, and will probably end up being deleted. You could post answer question, and refer back to this question using the URL - however, as you say, you have the exact same issue, so it would end up being closed as a duplicate - unless you add why the proposed solution (in the other - partially incomplete - answer) didn't work. Or a place a bounty on the question.