text:
Elegoo Mars 2 is printing randomly in the wrong places
After damaging my LCD plate while removing hardened resin (after my FEP failed and resin hardened onto the LCD) my printer started to harden resin in areas around the printed part. It started out being a bit of resin partially hardened to the FEP. I then replaced the damaged LCD with a new one, but the problem is getting worse. It now builds whole areas that are not part of the print. It seems like the LCD is creating these printed areas.
Is there a solution to this? I can't find anybody else having this problem.
Correction, Elegoo has a firmware update which is to correct a problem where resin is hardened all over the plate. This update seems to have failed to completely correct my problems.
First image is before update, second and third images are after the update.

Did you ever resolve this issue?

Yes, I resolved it, with a suggestion from Elegoo. The problem was with a faulty LCD panel. When I started a test of the new panel, without a tray of resin, the panel was obviously flickering badly. Replacing the panel with a new one solved it.

It is great that you found a solution, however... Please post your solution as an answer and not as a comment. Then please mark it as the accepted answer... Otherwise the whole Q&A mechanism of the site tends to fall apart. Thank you.


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What is the difference between allowance and tolerance?
I have to have a pin fit in a hole, and there needs to be a gap so the pin can turn freely.  Can I make the pin smaller by changing the tolerance?

There are four terms that many people find confusing:

Tolerance is the amount of random deviation or variation permitted for a given dimension.
Allowance is a planned difference between a nominal or reference value and an exact value.
Clearance is the intentional space between two parts.
Interference is the intentional overlap between two parts.

Use tolerance when specifying the amount of error permitted in making a part. Use allowance when specifying a gap between two mating parts.

Two other related terms that are important when specifying dimensions for manufacturing:

Accuracy is the maximum dimensional variation between parts.
Precision is the size of the steps your machine is capable of.

A machine cannot reliably produce parts with a smaller tolerance than its accuracy. If elephant foot expands your parts by 0.1 mm, then your accuracy is only 0.1 mm. You will not be able to repeatably print parts with 0.05 mm tolerance. (You might get lucky and one out of ten might accidentally fit the dimensions required, but that's not a good manufacturing plan.)
Precision is often confused with accuracy. People think that if their machine is advertised as having 0.05 mm step size (its precision is 0.05 mm) that they can print parts with 0.05 mm tolerance. But if your printer has a precision of 0.05mm and an accuracy of 0.1 mm, you cannot count on it to repeatedly position itself to within 0.05 mm of the desired dimension.
To measure your machine's accuracy, you'll need to print some pins and holes and carefully measure the differences between what you defined and what you printed. The difference between the largest and smallest measurements you take is the accuracy. And be sure to check the accuracy in your X, Y, and Z dimensions; your printer might have a difference between them that would impact the roundness of the parts.

In the case of the sizes needed to fit a pin in a hole so that it can pivot freely, you need to define an allowance in order to create the clearance you desire.
What is the minimum gap between parts you are looking for, and what is the maximum you can accept? That's the clearance.
Let's say you want a clearance of at least 0.2 mm between the pin and hole, but no more than 1.0 mm. And let's say you measured your printer's accuracy to be ± 0.2 mm. If you print a 5 mm pin, your pin would be anywhere between 5.0 mm ± 0.2 mm, so the hole must therefore be 5.6 mm ± 0.2 mm. The minimum clearance of 0.2 mm would be an minimum sized hole (5.4 mm) and a maximum sized pin (5.2 mm); the maximum clearance of 1.0 mm would be a maximum sized hole (5.8 mm) and a minimum sized pin (4.8 mm).
Note that a clearance of 1.0 mm is really loose, and is just too sloppy for your application. You might think to tighten the tolerances to 0.05 mm in order to reduce the clearance. But since your printer's accuracy can't produce a part that meets your specified tolerances, you would need to find a different way to manufacture or "finish" the parts.
The traditional way to solve the problem of inaccuracy in production is to create the part larger than the maximum material condition, then use a subtractive method to finish it to the desired dimensions.
Say we need the pin and hole to have 0.2 mm clearance, but we've already established that our machine only has 0.2 mm of accuracy. How do we print the parts to fit? We print the hole undersized and the pin oversized by the amount of accuracy in our machine, plus we include an allowance to ensure we always have some material to remove in the finishing step.
Let's establish the hole's final dimension to be 5.0 mm ± 0.05, so we print the hole to 4.7 mm ± 0.2 mm (resulting in a hole that's between 4.9 mm and 4.5 mm). After printing we run a 5 mm drill bit through it to finish it to 5.0 mm ± 0.05 mm.
Then we do a similar operation with the pin. Print it to 5.1 mm ± 0.2 mm (giving us a pin between 5.3 mm and 4.9 mm), then chuck it in a lathe or drill and carefully sand or file it until it becomes 4.8 mm ± 0.05. Now we finally have achieved our clearance of 0.2 mm ± 0.1 mm, which is a good enough fit for our purpose.
These types of secondary finishing steps have been used by craftspeople for hundreds of years.

Thanks for clearing that up. (I'll go renaming some constants in my OpenSCAD projects now...)

source: Stack Exchange

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

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Ok to shutdown printer after unloading filament, with no cool down?
With a fan cooled, all metal hotend, is there any reason to wait for the hotend to cool, before shutting down power, if the filament has been unloaded?
When leaving the filament on the machine after a print, I’m normally in the habit of waiting until the hotend has cooled down below the filament’s glass temperature before turning the printer off, because without the hotend fan running and the heat block hot, the filament can get softened up in cold end and potentially jam next time. But if there is no filament, would it stand to reason there isn’t enough remaining plastic in the hotend to get heat creep? And it doesn’t matter if the cold end gets hot?

While heat creep as you describe it is a concern, The more pressing reason to let a hotend cool off first is safety.
A hotend at printing temperature can be >200°C, with little to no airflow it may STAY at a dangerous temperature for a significant amount of time.
Not only can it burn you if it touches, It may be dangerous if the hotend starts moving after the printer turns off (In systems that cannot passively maintain Z especially)
Aswell, the remaining thermal energy may be enough to "cook" the residual polymers inside the nozzle or hot-zone, which can cause future clogging and extrusion issues.

not necessarily cook, but at least make a present clog worse..

If there is nothing out of plastic place nearby or inside, it should be fine. It won't take more than a couple of minutes to go down to 100 °C or so, so plastic leftover inside won't cook. Plastic outside from the mount may soften and weaken the assembly, so I would wait until the hotend is at 100 °C or so. With a fan on, it should happen in a minute or so.

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


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Thick stringing next to a perfectly printed model
Both items were printed at the same time. The item on the right was perfect while the one on the left has crazy thick strings. Sorry I didn't keep the build plate's orientation, you can see how they were positioned in the Cura screen cap.

I thought the stringing was from nozzle travel but if that were true the strings would be coming from the center pillar which they are not. Some of the strings shoot out from the left which doesn't make any sense.
I checked the bottom and it seems like the first layer is perfect or pretty damned close to it.
Sovol Sv01 pro

This is similar to an Ender 3 S1
direct drive
Creality silent board
CR touch
Marlin 2.0
hot end I'm not sure what's in there but it has a V6 nozzle rather than an MK8
PEI sheet
K value 2.0 - this was the factory setting
All the parts are pretty new since I bought the printer on an Amazon Prime day about a month ago.

Settings

Inland PETG - Yellow
a few days ago it had a 6hr session in a filament dryer
225 °C nozzle
70 °C bed
retraction 3.0 mm
print speed 60 mm/s
print acceleration 500 mm/s
jerk 12 mm/s

The max print speed of the premium quality 2.85 mm PETG I use, is 50 mm/s at higher temperatures you use (240 - 245 °C). I do have a no-name 1.75 mm PETG brand that prints at 230 °C, but that is with an expensive hotend capable of melting the PETG quick enough. You should increase temperature and lower print speed.

Are you using combing with max comb distance with no retract? Is it possible to share the G-code to check?

That's not stringing, that is a perimeter line that is missing from the item that was not deposited properly and "dragged" behind the nozzle. Misleveled most likely.

225°C is way too cool to print PETG, especially at 60 mm/s if your printer's extruder is similar to the Ender 3's stock extruder (going off what you said; I'm not familiar with your specific printer). It will be having serious trouble extruding, slipping in the filament gear, at which point you'll have too little material, so what does get extruded gets stretched out too thin and is under a lot of tension, and since it's not hot enough to bond well with the previous layer and also not thick enough to press well against the previous layer, it gets pulled across a diagonal rather than following the toolhead path.
Drop your speed for PETG to 30 mm/s or lower and increase the temperature to 235°C at a bare minimum. I would really call 245°C the minimum for PETG, but that's borderline too hot for the stock PTFE-lined heatbreak and will degrate the PTFE (and arguably offgas harmful fumes, although probably at levels way too low to actually be harmful) over time.

I was just using the default settings in Cura. I'll try 235 and 30mm

I did a temp tower and 235 was the best range. It was shiny and it didn't snap off easily. Did a benchy at 235 and 30mm and it was perfect. Thank you.

If you're not too busy I have another PETG question I'd like your input on. https://3dprinting.stackexchange.com/questions/19828/petg-benchy-boogers-and-stringing. Thanks.


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Why is my Ender 3 v2 knocking & misaligning for high Y?
On my Ender 3 v2 printer I recently and consistently get some knocking.
This happens in only two scenarios.
First, it now occurs all the time when printing the initial test strip gets near the top (high Y value), and knocks several times.
Secondly, it occurs if the model (sliced with Cura) has a high Y value (eg: if the model occupies most of the bed).
(If there is room and I move the model - in Cura - closer to the front there is no knocking.)
On the first 10 (or so) layers the printer sometimes knocks when a high Y value is reached and the entire model is thereafter shifted to the front by a few millimeters.
There is a third scenario. At the end of a print the print head is in the middle of the bed and moves up 20 mm then travels directly to the top left corner. At this corner there are 4 or 5 "knocks" (and the nozzle is 20 mm above the bed).
Any suggestions to diagnose/fix this problem will be much appreciated.

Embarassingly, I discovered that the cable to the heatbed was sometimes caught between the on/off switch and the adjacent power plug. So, for high Y values the cable was very tight and the bed could not be moved. Presumably the "knocking" came from the Y-axis motor. The problem was fixed by attaching this cable to the adjacent hotend/X axis motor cable.
Hopefully this will be helpful to others who have a similar problem. Please add a comment if you experienced this.

Your bed has become unleveled or skewed in Y direction.
When the nozzle is closer to the bed the extruder has to push harder to get the same filament flow through a smaller space, the stresses the extruder to a point that the stepper skips or grinds the filament. This is generally described as a knocking sound.
You need to find out why the bed is higher at the upper end of the Y range and fix this. Otherwise your bed has become warped and may need to be replaced. There are alternatives in using a sensor (e.g. a BLTouch) to sense the shape of the print surface, it will then automatically adjust for the shape during the first 10 mm (default value) of your print product. Installing a sensor requires new or alternative firmware.

Thanks Oscar. That is very helpful if there were only 2 scenarios. But, I found a third that suggests that closeness of nozzle to bed is not relevant.


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Consequences of setting the bed temperature too high with PLA?
On a printer with a heated bed, what are the consequences of setting the bed temperature too high went printing with PLA?

a small amount above the recommended setting, 5 Celsius for example
Considerably above it, 20 Celsius

I'm thinking of consequences for the print, not for the printer. Such as warping, adhesion, difficulty removing, and so on.

The biggest consequences of printing PLA with the bed too hot stem from difficulty cooling, especially for the layers close to the bed. PLA softens (or hardens, if you're looking at it from the other direction of cooling) around 50-65°C. When you have material in contact with a bed above that temperature, no amount of cooling fan will harden it. It will stay soft. If there's a big mass of material, just the viscosity may help it retain its shape well enough to meet your needs. If not, air pressure from the fan, friction with the nozzle, the pressure of the next layer beying extruded against it, etc. may displace the material from where it was supposed to be, giving you a print that's not just inaccurate but structurally unsound, or where support structures bond irremovably, or gaps that were designed into the model to be gaps fuse together, etc.
Even once you get a few mm away from such a hot bed, or even if the bed somewhat below the temperatures where PLA softens, you will still have greatly diminished cooling capacity. This is because the rate of heat transfer is proportional to the difference of temperatures. When PLA is at 70°C nearing hardening, hitting it with air that's 45°C will only cool it at half the rate as hitting it with air that's 20°C. Once the PLA is down to 60°C, the rates would differ by a factor of 3! This means you either need to give the PLA a lot more time to cool (print slower/longer minimum-layer-time) or use higher-flow fans that will pull in more cooler air from outside the print zone rather than just stirring around the hot air above the bed.
You can see some examples of how bed temperature's effects on cooling affect the print outcome in one of my older questions here: How do you solve PLA corner-curling short of printing really, REALLY slow?


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Why Does My 3D Printer Stop Extruding PLA?
I have an Ender 3 V2 which is around 6 months old. Recently, extruding slowed to an almost complete halt seconds into a print for no apparent reason. The extruder works perfectly when extruding manually (using the extrude setting) and I see no reason for it to not extrude properly. I am using Ultimaker Cura  and a new filament (my old one has the same issue). The print speed is 10mm/s and the temperature is correct for the filament which is PLA+.
After some testing it seems random when it stops extruding but it always happens within the first 10 seconds of the print starting.

Since you're not printing fast or anything, I think the most likely explanation is a loose or broken tension arm on the extruder. Check that it's gripping the filament and watch what happens when it stops working.

@R..GitHubSTOPHELPINGICE It can extrude manually when I turn the extrusion wheel by hand or when I use the extrude function under "move". It only stops whilst it is printing a model so I don't think it is the tension arm but I'll have a look and get back to you in a bit.

@R..GitHubSTOPHELPINGICE After having a look it seems that the extruder just starts turning incredibly slowly just after starting the print (never during the line that it does at the beginning of every print).

Wait, so it only extrudes the priming line, then nothing comes out for the model? Sounds like you have your slicer configured for extremely low or no flow, or wrong filament diameter.

@R..GitHubSTOPHELPINGICE It works for the 3 seconds (ish) on the actual print and then stops working. I will have a fiddle with the Slicer settings.

After changing the setting on Cura I have gotten it to extrude filaments consistently but now the filament won't stick to the build plate and sticks to the nozzle. Thanks for your help if you put your comment as an answer I'll be happy to accept it.

I have the same issue just for PLA+ with a Dremel 3D45. I can extrude Nylon, PETG, ABS with no problem. PLA+ filament comes out when I "purge" manually the material, but when printing it stops (and clogs the extruder) after few layers. I checked the Cura settings and they seems correct: 100% flow @ 210-230 °C.

@JacobBoughton The print not sticking to the bed is probably one of the most common problems; we all run into that from time to time. I’m sure there are good questions about that here, so search around. A few easy things to check are: nozzle distance at z=0; make sure the build plate is clean, not oily at all; nozzle temperature; bed temperature.

If it only extrudes the priming line, then nothing comes out for the model, this sounds like you have your slicer configured for extremely low or no flow, or wrong filament diameter. Check that any flow settings are at or near 100% and that the filament diameter in the machine, extruder, and material settings is correct (1.75 mm for most printers).


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How do I deliberately maximise stringing with PLA?
I'm using an Ender 5 with standard PLA and Creality slicer 4.8.2.
How can I deliberately maximise stringing, and if possible get it to be as consistent as possible.
My aim is to have "thousands of hair like threads strung between two rocky pillars".
If possible I'd like to do this in the slicer with PLA, rather than using cotton or some other material after the model has printed.

temperature tower

Eliminate retraction in slicer.
Print at a higher hot end temperature; something like +10°C higher than recommenced temperature.
Slow down speed hot end moves when not printing.
Maximize hot end movement without printing where you want strings.

I would add "disable pressure/linear advance"

Slicers will perform a retraction when moving from one solid to another, the value of which is part of the settings. I've not researched if a specific slicer will allow a negative retraction, but if it's possible, it's likely to create adjustable stringing.
If negative retraction is not possible, one can identify the retraction segments in g-code of the print and find/replace those values with extrude rather than retract. My slicer, Simplify3D does not support reversed retraction, but the code is clear when examined with a text editor:
G1 E-4.0000 F2400
G1 Z0.300 F1200
G1 X118.760 Y117.415 F12000
G1 Z0.250 F1200
G1 E0.0000 F2400
G92 E0.0000
G1 X122.415 Y113.760 E0.0972 F900
build g-code removed for clarity
G1 X118.760 Y117.415 E1.5303
G92 E0.0000
G1 E-4.0000 F2400
G1 Z0.300 F1200
G1 X158.280 Y117.216 F12000
G1 Z0.250 F1200
G1 E0.0000 F2400
G92 E0.0000
G1 X162.216 Y113.280 E0.1047 F900
build g-code removed for clarity
G1 X158.280 Y117.216 E1.5902
G92 E0.0000
G1 E-4.0000 F2400
build g-code removed for clarity
G1 E0.0000 F2400
G92 E0.0000
G1 X162.415 Y113.760 E0.0972 F900
build g-code removed for clarity
G1 X158.760 Y117.415 E1.5303
G92 E0.0000
G1 E-4.0000 F2400

All entries beginning with G1 E-4.0000 represent the 4 mm retraction called by the slicer. One could search for just that code and replace it with a positive value. Some experimentation is indicated to accomplish the desired result. The F value is feed rate and presents another value to adjust.
Pursuant to Oscar's comment, I overlooked the lack of movement as a factor. He is correct, such a modification is likely to create a blob. As a possible compensation, a better modification would be to create a custom extrusion code with a reduced flow rate, using the existing code as a reference.
This starts to complicate the process substantially, requiring far more calculations and edits. I suggest that it could yet be accomplished, but would be more easily done so with post processing of the code via Python or similar, with which I am not qualified to address.

Inverted retraction (normal extrusion ) is now done stationary, this may cause for a blob, maybe it is better to extrude while moving? Or, not retract at all.


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Can I print multiple parts in a single G-code file?
I have 12 parts for a model I want to print but I would like to know if I can put all of them in a single G-code file and print that on its own. Would this affect the model in any way?
I’m using PLA on my Ender 3 Pro

I have 12 parts for a model I want to print but I would like to know if I can put all of them in a single G-code file and print that on its own.

You certainly can. The printer doesn't care how many parts there are. Many single parts, like those with holes, will have layers that have areas that aren't contiguous. To the printer, multiple parts look just like a single part that happens not to be connected.
That said, printing multiple parts at once means that the job will be larger and take longer, and a problem printing any of those parts can force you to stop the whole job. Because small parts have less area in contact with the bed, small parts are more likely to come loose from the bed during  the print, so running a job with many small parts can be risky -- if any one part comes loose, you might lose all the time and material you put into the whole job.
One tool that can help mitigate that risk is the Cancel Objects plugin for OctoPrint. If you use OctoPrint to manage your printer, you can use the plugin to stop further work on any objects that have problems during the print and continue with the rest. Here's a video about using Cancel Objects.
Also, when printing multiple parts, be sure to check that you have enough material (filament, resin, etc) available to complete the whole job.

This answer assumes FDM printing -- for resin printers, as I understand it, as long as there's flow space between parts, if they fit on the build plate, they'll print.
For FDM, generally, you'll get better print quality printing a single part, because layers don't cool while you print the same layer for each of the other parts (meaning layer adhesion will be better).  That said, if the parts are very small, this additional cooling may be an improvement vs. having to set your slicer to provide a pause between layers to avoid slumps and layer spreading.
A compromise, if the parts are low enough, is that most slicers can be instructed to print the parts sequentially -- that is, print all of part A, then all of part B, and so forth.  This has some limitation in that all parts already printed must clear parts of the machine, and may also require larger clearance between parts for items like fan shrouds.
But printing a bunch of parts at one time does work, if the compromises in layer adhesion and other quality issues related to traveling between parts are acceptable.  The only way to be sure is to print the whole lot (perhaps with a large nozzle and thick layers, low infill, etc. to minimize filament consumption and print time) and see if they're good enough.

How much layers cool from one to the next has nothing to do with how many parts you're printing; it's really a function of how much there is to print in each layer. If you're printing a single large part with infill, you're going to get much more cooling between layers than you will if you're printing half a dozen small parts. IOW, the printer doesn't know or care whether the area it's printing is contiguous or not.

Would this affect the model in any way?

Resin would be fine.
Filament is more problematic. Printing multiple items increases the chance of a problem with one eg. a failed support, impacting on the others.
You also increase the chance of stringing between items and can have problems with layer adhesion higher up the print.
Having said that.... I do it all the time, because it's just easier. The only real concession I make is that I check periodically that the first couple of layers are fine, after that I just let it do it's thing.
The only filament I do it differently is TPU because I turn off retraction, without retraction it's guaranteed stringing between parts, so when I do multiple ones I always join them into one with a couple of lines then cut the joins off afterwards.

With a printer that has all the physical/mechanical problems worked out, and with slicing configuration tuned to make sure the slicer isn't doing anything stupid to introduce problems, printing a whole plate of parts at a time should be no problem. This is how folks use high-end CoreXY and Cross-XY printers printing more printer parts (to sell, etc.) all the time.
But if your printer sometimes has problems, doing multiple parts at a time drastically increases your risk that something will fail and mess up all the parts on the plate. And unless your printer is really fast, there's not a whole lot of benefit to plating a large number of parts together. Having to manually start a new job after a 6-hour job finishes is usually not a big deal unless you're trying to take advantage of overnights, which are an even worse idea if your printer isn't reliable. But on a fast printing setup, having to start a new job every 20 minutes rather than a plate after 3 hours is a big productivity killer, making large plates more attractive.


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Prevent postion from reset to 0.0.0 when serial goes offline
My hardware Arduino Mega with RAMPS 1.6 with Marlin 1.0.2 and powered by external power to prevent my board from losing memory, when I reconnect the USB and serial goes offline, the board set last position e.g 10,0,0 to 0,0,0 as x,y,z
How to prevent last position  from reset ?

Easy answer is to not reconnect the USB, maybe you need to explain why you reconnect.

The problem not with marlin,
The board is reset by the Serial port DTR line going low and pulsing the Arduino reset pin,
You can prevent this if you can disable DTR on your PC or by removing the capacitor that connects the DTR Serial pin to the reset pin.


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Dremel 3D45 does not honor temperature settings
I set:

G-code override: false
filament: PETG
nozzle temperature: 245 °C

Here the pictures that state the above points:

When loading the model, it also confirms the nozzle temperature of 245 °C:

But when running, it uses another temperature (230 °C) that is even different of what the G-code contains:

Why? What is my mistake?

If the "prioritize G-code" flag is on, the machine would follow the M104 and M109 commands contained in the G-code. If true, the machine uses the default filament settings as per the above image.

Try using your own gcode, printing a single line or simply moving on x and y btw different nozzle temp, and see what happens.I would try this. Check if Cura doesn't add some post-processing code too, sometimes we forgot to remove/disable them.


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Creality CR Touch not precise enough
I have the problem that the bed auto level functionality is working but not precise enough so that the first layer doesn't stick everywhere and the "paper sheet check" for each corner gives different results.
I have a Creality Ender 3 V2 with CR Touch auto level sensor and Marlin firmware (Marlin bugfix-JyersUI v2.0.1 (Nov  5 2021 21:19:16)).
I do the bed auto level either via G-code G29 in each print-file it self or via OctoPrint Bed Visualizer:
M140 S60 ; starting by heating the bed for nominal mesh accuracy
M117 Homing all axes ; send message to printer display
G28      ; home all axes
M420 S0  ; Turning off bed leveling while probing, if firmware is set
         ; to restore after G28
M117 Heating the bed ; send message to printer display
M190 S60 ; waiting until the bed is fully warmed up
M300 S1000 P500 ; chirp to indicate bed mesh levels is initializing
M117 Creating the bed mesh levels ; send message to printer display
M155 S30 ; reduce temperature reporting rate to reduce output pollution
@BEDLEVELVISUALIZER ; tell the plugin to watch for reported mesh
G29 T      ; run bilinear probing
M155 S3  ; reset temperature reporting
M140 S0 ; cooling down the bed
M500 ; store mesh in EEPROM
M300 S440 P200 ; make calibration completed tones
M300 S660 P250
M300 S880 P300
M117 Bed mesh levels completed ; send message to printer display

I added M420 S1 into all my G-code print files.
I checked that the auto leveling is active by sending single commands via terminal to the printer:
After Homing Z the Z value is as expected: 0 (zero).
After activating auto level compensation with M420 S1 it stays zero. Then I move the printer into a corner with G0 x120 y120 z1 F5000 followed by G0 Z0.
Then M114 shows Recv: X:120.00 Y:120.00 Z:0.00 E:32.24 Count X:9600 Y:9600 Z:-7". The Z: -7  shows me that auto leveling is doing something.
But when I check in the corner the "paper sheet check" shows different results in the corner than in the center (where I calibrated the Z-offset with the "paper sheet check").
Also the bed visualizer doesn't show the same results when I run it twice in sequence (the standard deviation of the sensor is supposed to be 0.001 mm):
First run:

Second run:

M48 P10 on my machine results in
Send: M48 P10
Recv: M48 Z-Probe Repeatability Test
[...]
Recv: Finished!
Recv: Mean: -0.005500 Min: -0.007 Max: -0.003 Range: 0.005
Recv: Standard Deviation: 0.001204

Which looks similar, I guess? (Open question: Does my firmware even have the AUTO_BED_LEVELING_UBL option? How can I find out?)
I could not feed any wiggle room on any axis of my printer, or the nozzle or the CR touch sensor.
So my question is: What could be wrong with my printer? I assume the BL/CR touch sensor works for other people as expected.

Wouldn't it be better to have a separate question on AUTO_BED_LEVELING_UBL so that it can be answered separately? E.g. to answer that we require more info how you got the firmware or whether you compiled it yourself. The answer is in the configuration file, as long as it is unknown what configuration file is used, it cannot be answered.

Since I couldn't find out which options are active for my image I downloaded one with UBL Leveling explicitly active (https://github.com/Jyers/Marlin/releases/tag/v2.0.1) and after first tests it is better now.  The other binary I used before was also downloaded from there : https://github.com/Jyers/Marlin/releases/download/v2.0.1/E3V2-BLTouch-5x5-v4.2.2-v2.0.1.bin

I found now out which leveling method is used: AUTO_BED_LEVELING_BILINEAR


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Can I cancel a G26 that’s already underway?
I’m spending hours trying to get a bed mesh that gives me a reliable first layer.  I’ve got CHEP’s concentric square pattern printing reliably, but real objects still fail, and the G26 test pattern in Marlin FW is failing immediately.
Can I kill a G26 R999 that’s already begun, once I get filament balling up on my nozzle?

You can pull the power cord from the socket, or reset the board.

Not with a command
You can not cancel any commands once they have started to execute unless you abort the print or powercycle: any normal interrupt command you send (like "pause") is queued after the current command is executed in the line.
Aborting is losing your print
So you need to trigger a function without a G or M code. The most common solution is Powercycling - which forces the board to hard re-boot.
Another way to force a reboot is to connect the "reset" pin with 5V.
Or you connect the printer to a machine via a USB connection, which, to initialize that connection forces a reboot.
Another solution is using the machine's "Abort print" function. This bypasses the command queue and triggers pretty much a soft reboot.
In all cases, the print is lost.


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Extra extrusion at seam of print with PETG
I recently purchased a spool of PETG to try working with it. I have managed to dial in most of the settings in Prusaslicer but one, in particular, is giving me a problem. As seen in the photo, the clip I printed has extra extrusion on the inside and outside. I have noticed that the nozzle will pause at the seam for about 5 secs before continuing. (The bottom is not Elephant's foot, I just didn't clean off all the brim)

I positioned the seam on the inside of the model. I know that the extra extrusion is caused by the seam but why would it also appear on the outside of the model?

I have printed the same clip in PLA without any printing errors. What setting within Prusaslicer needs to change so I can get rid of the extra plastic on the inside and outside of the print?
[I don't know what relevant print settings are needed to solve this problem, but will edit the question when I get some guidance.]

It's very likely just wet. PETG does awful things on resuming extrusion after retract/travel when it's wet. Unless it's been activelly dried in the past week and stored in a sealed container with fresh/dried dessicant, PETG is wet.

Funny enough, it has been in a filament dryer for the past week.

It depends how good the filament dryer is. If it's completely closed and no air can get in/out, the humidity stays inside.

What @FarO said. There are plenty of bad filament dryers that don't actually work.

While the idea of "wet" filament is possible, it would manifest itself over the whole model not just in one area. As seen in the photo, the front and sides of the print are fine; the area where the seam occurs is noticeably bad. But another solution was found.

After checking several places online, I finally got an answer in a Discord chat.
The solution was to turn off the Power-loss recovery setting on the printer itself.
After that was done, the print came out beautifully.

I just thought of that when I saw this question bumped and came here just to suggest you check that. Yep, power-loss recovery is the most horrible anti-feature on these printers. It's designed to stall the printer for a long time after unretracting but before printing by performing the (long, blocking) SD card write at the first print (extrusion+motion) move of a new layer. It's just horribly misdesigned and useless and needs to be turned off.

@R..GitHubSTOPHELPINGICE Very true. Just another example of a great idea that was poorly executed.

Yep. Executing the idea well is rather hard though. To actually work well it'd need something like a small UPS to power the printer minus bed heater until next layer change, then pause, park the head (so the hotend doesn't sit on the print and ruin it), and record state for recovery. It also needs a printer that homes at max Z, not min Z, so that Z can be re-homed without destroying the print, and that has very good homing reproducibility in X and Y. And it needs a bed surface that doesn't release the print on cooling. And.....

Looks like Retract at layer change is causing this. Disable that and see. This will help you to improve the quality a lot.
It will be under retraction settings:

After disabling "Retract on layer change", the problem still exists.


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No way to stick PETG on buildplate
I did my homework reading similar questions, like this, this and this.
Here a video that shows the issue:

The filament is PETG from JAYO and the printer is a Dremel 3D45.
As you can see, the filament does not stick on the buildplate. The manufacturer suggests to use 220-250 °C for the nozzle and 70-80 °C for the bed.
Here what I tried so far:

add purple glue from Dremel
bed temperature from 70 to 80 °C
nozzle temperature from 235 to 250 °C (below 230 °C it does not come out from the nozzle at all)
print speed from 50 to 70 mm/s
nozzle gap from 0.0 to 0.4 mm (in step of 0.1 mm). The video was taken with the maximum gap. When the gap is lower, almost all the filament sticks to the nozzle
fan speed from 0 % to 50 %
the filament is inside a filament dryer
clean up the nozzle
before each print I level and calibrate the buildplate

Honestly I don't know what to do further.
From your experience what should I do to avoid what you see in the video?

Your nozzle is very much too high to properly print just about any filament. If the filament sticks to the nozzle after it is positioned closer to the bed, you have two problems. The first is the initial layer position, sometimes called z-offset. The second is bed adhesion.
While the bed is cool, clean it carefully using the appropriate substance for your bed. I'm not familiar with that specific printer, but a glass bed can be cleaned by just about anything, while PEI beds should not have acetone as the cleaning substance. IPA or Denatured Alcohol is pretty safe.
Once you can get a clean bed and good adhesion, bring the nozzle back to an appropriate height. 0.4 mm is the most common nozzle diameter (perhaps until lately) and will provide near zero adhesion. 0.15 is the value I use for my printer, but each printer will be different.
You don't want ropy stringy build lines, nor do you want a nozzle that flattens the filament into something you can't remove when cool. I've had too-low nozzle height in which the filament was nearly transparent and was nearly impossible to remove.

With one brand of PETG I used 110 degrees on the build plate and 240 for the nozzle. Couldn't get a decent first layer before that.

I agree with fred_dot_u, you are too far away from the bed. If you can't get it after that, I would suggest using Bed Weld by Layerneer.


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References wanted for designing customized support
I am interested in references to designs which use a customized support instead of the slicer's default normal/tree support.
The background is this: I am making a hubcap with a 3D logo. I do not want to place the logo on the print bed because the logo will become very messy. So, I place the rim of the hubcap on the bed. This means that a lot of support is needed. With support = normal the print time taken is 36.5 hours using 290 g of filament. With support = tree the time taken is 29.5 hours using 200 g of filament. In comparison, with support = none the time taken is 14.5 hours using 115 g of filament, but of course is not practical. So, I decided to make my own support and I manually inserted it at a specified layer - just below the top disk and the logo above it. The design included some small brackets to hold the support. The time taken and amount of filament is the same as no support - about half the time & amount for tree support! Here is what the support looks like:

I intended to snip away the mesh, but it blends in quite well with the layer above it. (Perhaps a finer mesh is easier to remove.)
I am interested to know of others who have designed customized supports.

I’m voting to close this question because it does not pose a question. This is not reddit: we don't discuss prompts. We are a strict Q&A site.

Your question may be closed for being somewhat vague and outside the scope of the SE, but consider to view Maker's Muse video about creating alternatives to slicer-generated supports.
The video suggests creating primitives in locations appropriate to the overall design. For example, an unsupported "shelf" or "ledge" could result in a massive number of supports if left to the slicer. The MM method suggests that a small rectangular prism on the edge of the ledge turns the object from an unsupported item to a bridging solution. If the gap is excessive, multiple primitives in strategic locations would reduce the slicer-generated support.

Image is screen shot from linked video.
I've had to print a counterbore that I did not want to load with supports. The primitive was a simple cylinder with a diameter of 0.4 mm larger than the diameter of the hole. This created a peg attached to the edge of the counterbore, which the slicer saw as a bridging solution. Easily snapped clean after the print completed.

The curious thing about this Q is that the OP has created his own solution using something similar to Maker's Muse. His "question" is "I am interested to know of others who have designed customized supports."

In this situation I probably wouldn't use supports at all.
I'd put something round on the bed that fits the space instead.


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Are plastic resin vats inherently inferior to metal ones?
I'm looking at getting several resin vats. So that I can use different colors of resin without having to worry about cleaning them out between prints.
Are plastic vats inherently inferior to metal ones, and if so what issues might I run into. I'm a hobbyist, I'm not running a farm. So 3 or fewer prints a week.

At that rate one vat is enough
With 3 or less prints, you have enough time to drain the resin back into the bottle and prevent it from aging. Multiple Vats only become relevant if you need speed to swap between materials - which for a hobbyist generally is not an issue.
For swapping often, you need maybe two identical vats fitting your machine
Even if you increase your work rate, you only need at worst two vats that belong to your machine type: remove one, put it out to drain, insert the other one, fill it. That reduces the gap between material swaps to minutes instead of hours.
Only rarely you benefit from more...
You don't generally get too much more benefit from having more vats. The only upside you get from more vats is, if you have a small range of colors and swap often. But then you also need vats that have a lid, because you need to seal your vats for storage.
Material of the vat doesn't matter usually
The vat can be from whatever material it wants, it needs to belong to the machine. You can't use an Elego Mars vat in a Prusa machine, and neither in a Stratasys SLA. You are locked into the ecosystem of replacement parts from your printer supplier, so you have to use the parts for your printer anyway.


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Metal coating 3D printed parts (electroless plating)
I know that 3D printed parts can be coated in metal by painting them with conductive paint (graphite or copper seems to be usual) and then electroplating them in a commercial copper or nickel bath. The disadvantage of this process is that it does not coat insides very well, because those are not reached by the electric field.
I know that in the industry for plating ABS-parts with chrome and other metals, there is a process used where first the ABS is etched, then seeded with electroless catalytic palladium and then there are various options, for example electroless nickel or chrome.
I tried to etch both FDM printed ABS and ABS-like resin prints in NaOH, then after rinsing, dropped them in a commercial palladium activator and, after rinsing again, then in an electroless nickel bath, without any effect.
Does anyone have an idea on how to metal plate 3D printed parts (by electroless plating, meaning no electricity involved) and can shed some light on the chemicals used? I would prefer to mix them myself.

You did not use FDM but a Resin printer, yes?

I tried both. Edited the question to make that clear

I can only say that Resin from Resin printers is not etchable with common materials... maybe your ABS is modified or your base too weak?

I would try again using the suggestion from Marvin but with PC-ABS by Polymaker, designed specifically to ease electroplating. https://eu.polymaker.com/product/polymaker-pc-abs/

Good day, I have experience in applying electroless nickel on difficult 3D parts, in your case, it's exceedingly difficult to do it directly to the printed piece. You will need to seal the piece with a more benign coating that will accept the palladium activator. Also, a sensitizer before the activator is needed.
Try this.
Try your original procedure, but this time use just before the palladium activator, a stannous chloride solution (20 g per 1 L of deionized Water and 10 ml of muriatic acid), submerge the piece in the solution for 1 minute, rinse in deionized water and then place the piece on the palladium activator for 1 minute (don't rinse the activator) and then place the piece directly on the electroless nickel plating bath.
If that still does not produce good results, then you will need to seal the piece with a two-part epoxy sealer and do the process again.

Thank you very much for that answer! What type of 3D parts do you coat that way? PLA? ABS? Or some Resin?

I have coated all of those, the Easiest is Resin, the hardest is ABS and PLA, it's much easier to just coat them with 2 part epoxy, the best so far is XTC-3D

Ok. I ordered tin(ii) chloride, the rest I already have. I will try that.

@iblue Often time the issue is related to the water surface tension of the piece, most of the 3D print materials have very high water tension and even when submerged for minutes the sensitizer and activator just don't coat the surface. In this case you will need to reduce water surface tension with a wetting agent. You can order some from angelgilding.com the 15 or the 28 buck ones are good for this type of projects. Or if you need to make it yourself let me know I have the formula.

Here is the website for the wetting agent https://angelgilding.com/wetting-agent.html

Thanks for the info. Shipping to Germany is "request a quote", which usually hints that I cannot afford it. I already have some sodium laureth sulfate from previous experiments. Will that do?

It's not going to work since the wetting properties needs to persist even after the piece are washed/rinsed. You have two options. 1. a blow torch to reduce the surface water tension(it can be tricky) or making your own formula. This is what it has worked for me. 500ml of Apple Cider Vinegar, 10 grams of instant coffee powder, 100ml of 90% isopropyl alcohol. mix them at room temperature(30C where I live) to test it's properties you can grab a simple Polypropylene spoon rub some of the wetting agent on. Water will sheet of and the spoon remains wet

Check and see these two videos, this one is Before wetting agent. https://www.youtube.com/watch?v=9pBcekRzi_k and After Wetting agent https://www.youtube.com/watch?v=5NJ5-m1Z1KQ that is what you are looking for

So i made some experiments. It works about the same on resin, ABS and PLA, but on PLA it does rub off, on ABS and resin the Nickel coating sticks very well. On all three I do not get uniform plating, but dull spots, about 50-70% of the surface. I tried with and without the wetting agent with approximately the same results. ABS and PLA I etched in some KOH (400 g/l) before the whole process. The plated metal is very thin and has bad conductance. Any tips?

I believe I mentioned that even with good treatment the issue may persist due to their surface. I recomend sealing it with an 2K epoxy coating like XTC-3D Coating.

Also, I have never used an Etch on my parts, so you might want to try to skip that part and see how it does..

There is another option where the plating is done like brushing paint. The electroplating is just done a different way but has the same effect.
It's called brush plating. There's a bunch of different products (none of which I have tried) and the youtube results are pretty impressive. They do need a current as it's electroplating, but you don't immerse the object, the current is through the brush etc,.

You can use semiconductor processes like evaporation, sputtering, and chemical vapor deposition.  These are expensive.  Sputtering is probably the most feasable but it will have trouble with shadows.


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Prints not sticking to bed or just not extruding?
I'm very new to 3D printing. When my printer was new, I got loads of really good prints, however, now they're all failing.
I suspected that the nozzle was in bad shape, so I replaced it, but even now, the prints are still quite bad.
I suspect that the filament is not coming out properly. (extruding?)
I have a Creality Ender CR6 SE. and I'm using Overture Matte White PLA. I've tried using the default 200 °C nozzle and 60 °C print bed temperatures and I've also tried on the upper end of the recommended temperatures at 230 °C and 70 °C.
I've also tried reducing the print speed to 70 %.
Here is a picture of the first layer of  a raft:

And here's a picture of a few layers in (still of the raft):

Just before this print I did an auto-level and cleaned the printbed with warm soapy water.
This is the print if I leave it going:

Additional Info: I used the auto-level feature on the CR 6 SE before any of the pictures and used Cura Slicer for slicing.
When using the hairspray method, I managed to get a print out - that print is a 3D Benchy:

Not looking too good. Also - as you can see, I used a different filament.
Using the hairspray again, I tried printing this:

But ended up with this:

UPDATE 3
Ok, So I've found something that's probably not a good thing and I need some advice on it. I think the problem is with the print bed. I  found that it can wobble. If I put slight pressure on the front of the bed, the front goes down and the back goes up. Not by much, but there's definite give.
When I print a big circle, the left of the circle is "thinner" than it should be, unless I push down slightly on the print bed. If I do that, then the print thickness on that part of the bed seems to be correct.
However, if I keep that pressure while the nozzle goes around then the print loses adhesion. As soon as I release the pressure and the print bed goes back to what it was, then the print regains adhesion (on that side).
However, if I leave it like that, then the nozzle will be too close to the bed on the other side again.
Now I know. This is a tramming (leveling - are these words completely synonymous?) issue, but when I paid extra for the auto-leveling with the Ender CR6 SE, I paid that extra so that I wouldn't need to mess around with stuff like this. Is this money wasted?
Print nozzle too close on the left, too far on the right:

Should I contact Creality and try to return the printer and get a cheaper one that I'm going to have to manually level/tram anyway?

Have you tried using any kind of adhesion, i.e. glue stick, hairspray, or blue painter's tape? When I had problems with print adhesion, I first tried blue painter's tape (that worked too well) but then settled on using a glue stick.

Hi @agarza, thanks for the feedback. No, I have not, however, that's not really the problem here. I mean, yes it's part of the problem, but the fact is that prints are failling as well as not adhering.

The first few layers are probably the most crucial to getting a good print. I would suggest double-checking to make sure your bed is leveled (trammed) [How do you level (or tram) your build surface correctly?] then if prints are still not sticking try additional adhesion helpers (glue stick, hairspray, painter's tape). I will say that it did take me a while to get the "sweet spot" for getting good prints.

There are multiple issues here, the first layer is just one of them. Other issues may include underextrusion or retraction problems or a problem with the extruder.

What slicer did you use ? It seems the travel speed is too high, and the print speed too. For PLA @ 200°C: try 44mm/sec. and 22mm/s for wall. Initial layer at 30mm/s and reduce your travel speed, so when retracting Z, the filament detach from current layer.

As for the print bed wobbling, it may be that the eccentric nuts for the Y-axis are not tightened enough (see this answer for additional info Bed wobbling on Ender 3 and this YouTube video on adjustments)

The CR-6 SE uses strain gauge based sensing for the auto leveling. This implies that the nozzle itself is the probe for the leveling procedure. It is important that there is no filament left on the nozzle and no debris is on the bed (of so, this causes incorrect measurement of the bed surface and results in a too large of a gap between the nozzle and the bed).
Normally, when you replace a nozzle, you need to re-assess the distance between the nozzle and bed with the so-called "paper thickness" method.
This video of the CR-6 shows that paper is still required:

As seen from the first layer of the raft (which by the way is totally unnecessary for PLA) the nozzle is too far from the bed, you see this in balling up of filament and cutting corners where filament is dragged and not deposited. The video does show that it is required to set the Z-offset to the correct value during the printing of the first layer. It is advisable to decrease the Z-offset, alternatively you can set a Z-offset in the slicer, e.g. Ultimaker Cura has a plugin called Z-offset made by Fieldofview to set a different offset directly as slicer option.
You may also have an adhesion problem, probably caused by the incorrect distance, but an adhesive might be beneficial too.
Reprint and post a question on the quality of the print.

The auto-leveling process puts the nozle at 0.20. I can manually reduce that to 0.15, but when I do that the print fails completely, the first layer doesn't even print.

@Jim Have you checked your extruder (it also under extrudes), there are more issues with the printer I think. Also, have you degreased the print bed surface?

yes, I cleaaned the  print bed with soapy water. As regards to over/under extruding - I'm super new  to 3D printing and do not know what I'm  doing. This is why i'm asking for help here. And yes - I think there are more issues with the printer - I've updated the  question.

It almost looks like that nozzle is too far away from the bed. Try releveling your bed.

This is really a comment, not an answer. With a bit more rep, you will be able to post comments.

Hi and welcome to SE.3DP. Whilst I have upvoted your answer (just to give you some reputation), it should be said that, as argarza implies, your answer is a little brief. Could you [edit] your answer and explain why you think that the nozzle is too far away from the bed - what are the clues/indicators that make you think that? It could help to make your answer a litle more instructive/constructive. Also please take the [tour]. Thanks.

Great Idea, And I tried auto-leveling my printbed before any of those pictures - sorry, I forgot to mention it in the question - but i'll add it now.

I'd be inclined to blame the filament. So my first troubleshooting measure would be to use another filament. If the problem persisted then I'd check all the belts are tight and give the printer a clean with some canned air.
This is assuming your levelling and settings are the same as when it was working ok. Not sure about this assumption because it does look as if your levelling is off for the first layer.


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Which filament is best for printing parts that will endue a constant load for a long period of time?
I thought the answer was ABS, but I read about how some people used it to print parts that were used in plumbing, and they failed when put under constant load, and some said that PETG is better for this application. I want to print bases for my table legs, would PETG be a better material to use?

source for ABS failing? it's quite important to know the source to get further details. Maybe (likely) it was ABS+

Table base means high compressive strength. Even if they are for a piano, any material will do. PLA will work just fine.

PETG creeps more than ABS/ASA, so I think you should still pick those. Be sure to print them hot and in a closed chamber, but you are loading in compression, so you won't have big issues.
See these tests for creep:

The conclusion is that ASA deforms in the beginning and then it stops. PETG in tensile keeps stretching, but in compression seems fine.
I think ABS is still the best, especially if you use a pure ABS, not an ABS+. Rather than an ABS+ use ASA.
Since it's not critical and if it breaks it's no big deal (likely it will get thinner with time), PETG is an alternative you can try.

PETG creeps but PET doesn't.

It creeps but not much

For table leg stoppers and things like sandwich signs I use TPU, never had a problem with them yet. They're flexible and strong. Which means you can design them to insert easily and lock themselves in place. They're forgiving if your table leg is not quite evenly prepared at the bottom.
The only problem I can think of which would also apply to any other material is if they have to deal with a sharp edge.


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Does Silk PLA really contains elastomers as additives?
I have heard many times that silk PLA is PLA with some unspecified elastomers in it, but without any reliable reference to confirm this statement.
If it contains elastomers it should be more flexible and elastic than standard PLA I guess, but I have tried many silk brands and this doesn't seems true and actually in my experience on contrary it looks like harder and "less" elastic than standard PLA on average.
Since all silk seem behaving very similar, could be assumed that even if the specific blend changes from a brand to another with different secondary additives the "main recipe" ingredients are basically the same.
Does Silk PLA really contain elastomers as additives? If yes, since elastomers are an huge family what categories of elastomers?

Not an answer since I don't have a source for this, but I would speculate that you would need a significant portion of elastomer content to make the overall printed material stretchy/flexible. Anyway, in my experience silks are more "gummy", prone to fusing with nearby material (e.g. in print-in-place mechanisms) where they "tear" away and possibly damage the print rather than snapping cleanly like pure PLA would.

Probably it would be a significant amount to make it really elastic, but the point here is that is less elastic than standard PLA. Silk PLA is stickier to other surfaces when fused and is trickier to achieve good layer adhesion with no delamination issues but is not gummier and has a “glassier” consistence and slightly higher transition temperature (some degree more to start to became soft), or at least this is my experience trying many different brands of silk PLA

I'm not sure about differences in Tg, but my silk (YOUSU brand) prefers to print much cooler than normal PLA (200-210 vs 210-245) and is watery at higher temperatures, flowing out of the nozzle rather uncontrollably.


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Bigtree GTR V1.0 + M5 (Klipper) Can Klipper access my M5 expansion board?
Just a quick question, Does Klipper support Expansion Boards?


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Ender 3 v2 - Filament clog before nozzle
The filament "swells" up to the inner diameter of the feeding pipe, from the nozzle to about the end of the heat-sink. This happens after a few hours of printing. It happened using a new nozzle (0.2 mm) and a new tube - the same clog is the reason why I changed both.  When this happens, the filament can't be pulled from the tube - I had to cut it open on the end to remove the filament, thus shortening the tube with each clog. The nozzle had no filament in it when I removed it and isn't clogged up.
When installing the nozzle and tube, I first screw in the nozzle, heat it up and torque it a bit, then I slide the tube in all the way.

What kind of pipe and filament are you using? I am not sure about the core issue but regarding the tube cutting: caution about a too short tube length after some cutting repetitions. Also something like this cutting guide can help to get a nice orthogonal cut.

I found the issue. The fan, blowing on the heat sink is busy packing up. It must have stopped during a print (or not start at all). I now check that it is turning when the print starts (and check on it from time to time). I'll have to wait for stock to come in before I can replace it.

If not enough cooling on the cold end, the issue called "heat creep" kicks in. This is an excellent example of heat creep, thanks for answering your own question. Sorry to have missed your question, you would have gotten an answer sooner! :-) All-metal heat breaks are notorious for causing this issue.

Yes your description is related to heat creep (https://3dprinting.stackexchange.com/questions/15629/what-are-ways-to-avoid-heat-creep).  Looking at your question, I was going to suggest increasing the cooling of the heat sink to give a higher temperature gradient.  Your solution is consistent with that.


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What filament to use for outdoor high humidity, temperature, and payload?
I wanted to build a 4-wheel ground robot vehicle with a payload of 25 kg for outdoor use, but I wanted to make the frame/chassis using a 3D printer. The outside temperature ranges between 30 °C-35 °C and the humidity is 70-90%. I think the vehicle would be outside for 4 hours at a time. The dimensions of the vehicle would be about 1.0 m x 0.8 m x 0.8 m (LxWxH). From other stack exchange questions and some reading online, my choices have come down to ASA, PC, and Nylon. It's important that the printed part doesn't deform outside. I think I'm leaning towards Nylon for tensile strength, toughness, and heat deflection, but I don't know how the Nylon printed part will hold in high humidity.
Has anyone had experience with Nylon in the outdoor conditions I mentioned? Was it difficult to print a large surface area Nylon part (I'm thinking of printing with the filament directly coming out of an active dryer)? Which bed surface were you using? Would you recommend any other filaments?

The application doesn't look to be demanding at all from a material point of view. Operation below 40 °C and 70-90% RH is not that special.
Once taken out PLA for creep, most rigid filaments would work. Nylon deform under constant stress, so screws may get loose over time.
PETG, ABS, ABS+ (TitanX/niceABS are about as easy to print as PLA), ASA, ...
For ease of print, PETG or ABS+ should be fine, but ABS will deform more before breaking, while PETG tends to shatter when it breaks.

My first choice for this would be PET. Not PETG, which is a mess of blobbing, stringing, warping, creep under load, etc., but real PET, also known as BPET (bottle PET) or HTPET (high temperature PET, because it needs high temperatures to print and has high HDT)
Unlike ASA, PC, and nylon, PET is easy to print. It does not need a heated chamber or even a heated bed (although it does a little better with the bed a little above room temperature, at 30-45°C) and you don't have to fight with warping or compensate for significant part shrinkage.
The HTPET I use is rated for high HDT, 87°C as-is, and 100°C annealed. You can probably arrange for it to self-anneal during the printing process with the right settings; I'm planning to experiment with this at some point. To give you an idea how readily it anneals, the smokestack of a Benchy tends to anneal while printing it just from the accumulation of heat in a small area.
It needs high print temperatures. 275°C is about the minimum. The manufacturer of the HTPET I used recommends 285°C for high speed, but I've found flow increases all the way up to around 320°C if you want to go faster.
It is somewhat hard to find PET filament, despite it being fairly easy to make your own from recycling bottles. I would not really recommend that for your project because it's hard to get perfect flow to simultaneously ensure precision and part strength. There are at least a few manufacturers selling it in the US and probably elsewhere though.

Good idea, but PETG would work just fine as well...

@FarO: PETG reportedly experiences creep like PLA does - deformation over time under sustained load. That's why the Voron folks insist people not print the printer parts out of PETG. So that might be a reason not to use PETG. But so does nylon, possibly much worse. As I understand it, ASA, ABS, and real PET do not undergo creep.

It creeps but not much http://thrinter.com/creep-abs-pla-petg-alloy-910/ https://www.reddit.com/r/3Dprinting/comments/oic2un/pla_purple_vs_petg_pink_creep_same_load_two/  and https://www.youtube.com/watch?v=tmoWIxlXHGM What are your sources?

I see your point https://www.researchgate.net/publication/356676867_Accelerated_Aging_Effect_on_Mechanical_Properties_of_Common_3D-Printing_Polymers but it's not so standard, as you see from the previous comment


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PETG Benchy boogers and stringing
The Benchy looks good for the most part except for some boogers on the chimney

And some stringing on the bow, near the front deck.

Here are my settings. On another roll of Inland PETG, I printed a Benchy at 30 mm/s and it came out perfect. Is there any way to improve my results at higher speeds? Maybe 4 or 5 for retraction and/or faster retraction speeds? I figure I ask before taking shots in the dark. I was told to not go below 235 °C for PETG so that seems like lowering the temperature is out of the question.
Any ideas? Below are my settings.
The printer is a Sovol Sv01 Pro (this is similar to an Ender 3 S1)

direct drive extruder
Creality silent board
CR Touch
Marlin 2.0
hot end like and Ender 3 Pro with an MK8
PEI sheet
K value 2.0 - this was the factory setting

All the parts are pretty new since I bought the printer on an Amazon Prime day about a month ago.
Settings (using Inland PETG - Yellow):

a few days ago it had a 6hr session in a filament dryer
235 °C nozzle
70 °C bed
retraction 3.0 mm
print speed 40 mm/s
print acceleration 500 mm/s
jerk 12 mm/s

Is power loss recovery enabled? It will make blobs on each layer of your print (whether they're noticable varies by the geometry and slicing) by pausing to write status to the SD card on the first extrusion move of each layer. The extent of the blobbing will vary by how much the material oozes while dwelling and whether the material remelts when the nozzle sits in place on top of it.

What printer is this, is it a Sovol Sv01 Pro, or an Ender 3? Sovol is in the question, Ender in the tags.

@Oscar sorry that was a mistake.

It is based on an ATMEGA chip, which may struggle with high CPU load.
The blobs can be likely avoided by reducing complexity of the model when slicing, see video

If this is the Sovol Sv01 Pro printer, it uses a 32-bit Creality 4.2.2 board, that is not an ATMega board.

It's a sovol but it's using the Creality Silent board.

While you did use a dryer, the bumps on the surface look like moisture bubbles.  I've found it difficult to completely dry out PETG once it gains moisture, although drying is a great improvement.  Going straight from the filament dry pack to a dryer that feeds filament straight to the printer has done the best.


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Layer above support is very rough
I'm attaching a picture to show my issue. I'm hoping might be an easy settings fix, or at least maybe someone has a couple suggestions I can try. I'm using an Ender 3, and the program Cura. The print on the left was printed with the opening facing up. The print on the right with the hole facing down. The support leaves a rough surface. Any suggestions for support settings would be appreciated.

Have you found & fixed the problem? If any of the answers helped you to get an answer to your question or come to your own conclusions then please do vote & accept an answer (using the tick button next to it). This helps us reduce the unanswered questions list & stops the question from being bumped once in a while. If you found another answer (than those already posted), please add that answer (& accept after 48 hours) to share your experience with the community. If you have not been able to address the problem please update your question.

There's only so much you can do about this without a multi-material printer that can utilize dissolvable material or material that doesn't bond to the print material, and print the supports at zero distance from the model. So expect it to be ugly. But not quite that ugly.
Slicers, including Cura, have options to control the Z distance between the support material and your model, among other things. Reducing this will make it harder to remove the supports, but will give a better bottom surface. It only really works on whole-layer granularity in Cura (while some other slicers let you do arbitrary distances), and really should always be equal to one layer. A distance of two or more layers will give really bad results, which might be what you're seeing.
Also, Cura has an option called "support interface", which you want on. This prints a flat top surface on top of the support, below your print, so that all the lines of the print have something they're resting on. Without this, the bottom surface over the support will sag down between the lines of the support and look very bad - or, if it's a small detail, it might sink entirely between lines of the support and effectively not be supported at all!
Finally, one hack you can try if you don't have a multi-material printer but want to try printing supports at zero distance from your model: set support Z distance to zero and use a slicer plugin to pause-at-height just past the top surface of the support. Then, when the printer pauses, paint a release agent that won't bond to the print material on top of the support. Reportedly Sharpie permanent markers work as such a release agent, but I haven't tried this, and there are probably better choices.

Thank you for the response. Not new to 3d, but new to printing on my own. The ender 3 was from my cousin,  and it definitely has given me a lot to think about when I purchase another. I'll try adjusting those settings.

Interesting about the sharpie as release agent.  Idea:  paint PVA glue, like Elmer's as the release agent, then dissolve it in water later.  Similar to printing dissolveable support with PVA filament.

You cannot print into the air (hot filament will sag when not supported). Do remember that even with support enabled, you are printing into air. This is because there is always a gap between the print object and the support structure, the option is called Z distance. If there wasn't a gap, the print object will fuse to the support structure. You may want to increase fan cooling or decrease the Z distance between support and print object to get better print results, but, print orientation is also important, sometimes placing an object under an angle works. In the example you provided, it is clear that  it is better printed upright (unless there is a recess at the other side).
From experience, to increase the surface above the support structure, having the option Enable support interface enabled will add a dense surface on top of the support structure. This surface, in conjunction with the correct gap and cooling when dialed in correctly will provide better surfaces above support structures.

Z distance (in Ultimaker Cura)
This refers to the distance from the top and bottom of the support structure relative to the model. This setting is divided into the top distance and bottom distance. The top distance defines the distance between the top of the support and bottom of the model and the bottom distance refers to the distance between the bottom of the support and top part of the model.

A small distance between the support structure and parts of the model is necessary in order to remove the supports easily after the model has been printed. A low value creates a smoother surface, but can also make it more difficult to remove the support properly.

Thank you. I'm new to the whole 3d printing and it's a lot of settings to mess around with. Gonna mess with settings and also see if it gets better printed at an angle.

@RussellValois No problem, we were all new once!  Please use the voting buttons instead, as it is votes which drive the community. If I'm not mistaken, you are also new at Stack Exchange, please read the [help], accessible through the button with the question mark at the top right menu. Also take the [about]. Welcome at 3DPrinting.SE!

It is extra work, but if the overhang/recess is flat and parallel to the build plate, you can get a very nice surface finish, with a single material fdm printer. The trick is to put down a layer of blue masking tape  on a solid support structure the layer before the overhang prints.
You could model in a throwaway “plug” with your model, with a 1mm horizontal gap between it and the real walls, and a single layer gap (like .2mm) vertically between the plug and the overhang surface. Or one could potentially futz with the support settings to generate a solid interface layer on top of the support and a one layer gap between the interface and the overhang.
Once sliced, you program a pause at the end of the layer before the overhang.  It is good to program in few extras in the G-code: a movement to retract the filament to make it ooze less, and an X and Y G1 movement so the hotend doesn’t ooze on the model and make a lump. Last, a command to disable the X and Y motors so you can move the bed or carriage around to get it out of the way.
Once paused put down some blue masking tape over the pulg completely.  press it down and make an indent where the gap is.  Then cut out the plug shape in the masking tape with an exacto knife, following the indent.  Now is a good time to put the glue stick on the tape.
When ready to start the print again, home the X and Y axis, and extrude some filament, since undoubtedly the nozzle has oozed out the filament in the nozzle, you don’t want it shooting blanks when you start the next layer.
It is important to go SLOW when printing over the masking tape, or it won’t stick. It is also helpful to increase the extrusion temporarily to get it to stick better.  This can be done by hand, or programmed into the G-Code if you are running the job multiple times and don’t want to babysit.
When the print is done, the plug should be easily removed.  A little rinse of water can get rid of any residue from the glue stick.

Here is some example G-Code of the pause, taping, and aftermath:
G1 Z0.980 F9000.000 ; Z step to the layer with overhang to print
G1 E0.11935 F3900.00000 ; some extruder move
G92 E0 ; extruder length reset
G1 X25 ; move nozzle away from print
M18; disable steppers

@pause painters tape ; printer pauses and displays message. Add tape, cut out. When finished, prime nozzle, remove blob with tweezers, immediately click continue
G28 X0 ;home  X axis
G28 Y0 ;home Y axis
G92 E0 ; reset extrusion distance
G1 E-1 ;retract
G92 E0

M220 S25 ; slow speed to 25%, for better adhesion to painters tape.
;remember to add command later, after tape is covered, to speed it back to 100%
M221 S150 ; increase flow rate to 150%, to adhere to painters tape. return to 100% later!

G92 E0
G1 X130.071 Y164.894 F9000.000 ; print job continues...
G1 E1.50000 F3900.00000

Then later on, after the layer has gone down over the tape, add
M220 S100 ; return print speed to 100%
M221 S100 ; return extrusion rate to 100%


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Make a 3D print airtight 10 bar (140 psi)
I want to make some prints of pressure resistants. I am currently trying to print a simple cylinder to find the best parameters to make my prints airtight (by airtight I mean, it needs to resist to 10 bar).
Here is the test model that I have made for this:

Here are the parameters that I have changed in Cura:

layer height: 0.1 mm
infill : 100 %
print temp: 250 °C (high temp to make the layers stick between them)
wall line count: 5
infill overlap: 40 %
flow: 115 %

But all these changes in Cura don't give good results for ABS. It's not even airtight at 2.5 bar:

And here is a mid-cut of the print :

Do you have any ideas/suggestions to have better results? Can it be from the ABS itself? There is a sort of white powder between the layers, is this normal for ABS? Should I try using PETG? What could I change in my parameters?

If it is ABS, have you tried acetone smoothing? I also cannot get plain ASA to be watertight at 2 bar...

140psi is... it's a lot. Not that it will be impossible, but it might take a LOT of plastic.

100% fill means no tolerance to overextruding. There is no hollow space to dispose of the overextruded filament.

It's very difficult to get accurate internal sizing with 3D printing for this sort of application. It's also difficult to get it airtight without some sort of post-processing. My group wrote a paper on the flow dynamics of pressure restrictors made with 3D printing. In short, I'd suggest you use a drill or mill to produce such parts. We were using pressures < 0.1bar and still struggled to get them to seal without post-processing.

This is going to be hard. Even holding a vacuum is hard (I've tried it and not succeeded). I'm not sure what the mechanism of air molecules getting thru the print is - whether it's defects in inter-layer bonding, defects at seams, imperfect mating with the fitting, or even permeability of the plastic itself. It might not actually be existing flaws in the print, but rather the high pressure being a stronger force than the bonded layers can withstand, essentially ripping the layers apart from the weakest point until the pressure can discharge through the opening produced.
If using ABS, you might try an acetone bath followed by a long period of trying or use of vacuum chamber to quickly remove the solvent, if you can stand some possible part deformation. This would tend to fill any gaps. Coating with low-viscosity CA glue (Loctite 420 or equivalent) might be a better version of this approach, as the solvent will both attack the ABS and deliver fill material.
In principle PET (maybe also PETG, but PET is preferable anyway if you can get it) should be a suitable material for pressure vessels, as it's what's used for soda bottles at comparable pressure, but those are blown from a single piece, not fused together with seams.
At some point I will attempt this again, and will update my answer if I have any findings that contribute to your question.

I also thought about PETG for my similar part, I discarded it because of possible deformation due to creep and resulting leakage. It could be interesting to try PET. Maybe PP too? it is said to have perfect layer adhesion

I find PETG a lot more less prone to deformation than ABS,   ABS is absolutely a nightmare to print, if you do not have an enclosure, forget about ABS.   The key with PETG is to print with a bed of around 90 degrees will mitigate warping, and printer around 250 degrees for this particular application. Switch fan off.  It can also help when printing it fast.  XTC-3D epoxy treatment and heat treatment will help too.

"a lot more less prone"? That's... confusing at best. Is it "a lot more prone" or "a lot less prone", or is there some specific meaning to "a lot more less prone" that I'm not familiar with?

Not without postprocessing
FDM is pretty much welding plastic to plastic. Many many layers. Each of them is a potential breaking point, a corner for stress to arise and break the print.
Easy with a hollow body
Printing a hollow item that can be filled with resin is comparatively easy. Once filled with a monolithic curing resin (epoxy), that will take the pressure much better and seal it fully.


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Why is there some transparency between the layers of my print?
When I'm printing sometimes there is some "transparency" between the layers as you can see in the picture, I'm not sure how to name the problem.

I've looked on google, somes people said It could be the nozzle that is clogged, I cleaned it and it doesn't seem clogged.
I've also seen that it could be the pressure of the spring in the extruder arm, I adjusted it.
I also checked the bed level and it looks fine.
With all thoses changes et verifications I still have the problem, not even a small improve.
Some time ago I didn't have any problem, I didn't change the cura parameters, and the problem is for every 3D files, not only this one.
In your experience what could cause this ? Did I do something wrong ?
I have a artillery sidewinder x1 which I use together with Cura. I print in PLA at 200 °C. The print bed is set to 50 °C . I use a print cooling fan at 100 %. The layer height I set to 0.16 mm, the line width 0.44 from the 0.4 mm nozzle. The Printing Speed is set to 30 mm/s for walls and 60 mm/s for infill. My retraction is 5 mm at 45 mm/s.
EDIT 30/08/2022:
I have tried to print the gcode given by artillery (which is the manufacturer of the 3d printer), there is two files a cube and a chick, I have the same problem except that it's only the infill.

This file is supposed to be perfect for the printer so to my understanding the problem is not from the software setting in cura, but from the printer itself.

Hello Gregory, welcome to 3DPrinting.SE! Your question is lacking detail and as such is hard to answer without knowing a couple of things about your printer setup. Please [edit] and fill in the [placeholders] in the template I added and then remove the leading <!-- and trailing --> afterwards. This will turn it visible and help us help you find the actual problem.

I've just added all the details you asked for, it's almost all the settings from the profiles I downloaded from the manufacturer, I think I only changed the bed temperature.

Your problem is underextrusion, no doubt. The question is what is causing this. As a few hints, please inspect he extruder (the spring or filament tensioning mechanism) and the slicer (1.75 mm diameter and flow modifier), Also be sure it isn't in volumetric extrusion.

I've disassembled the extruder parts and clean everything, there was some dust, but not a big amount. I've reassembled every thing. I've adjusted the tension of the spring, the feeling was different than before when doing it, I think last time I disassembled things, I must have badly re-assembled it. The manufacturer print looks fine now. I'm trying my files now. I'll post a new comment when I have printed more files.

I found out what was the problem here, like @0scar said I think it was the tension spring that was wrongly set, even if I had checked it before.
Also the real name of the problem was "underextrusion" and not "transparency between the layers"
Here is the steps I followed to fix it:
I disassembled the extruder by removing the screw on the side like on the picture, there is also two behind the FAN.

After that I had access to every gear that was pulling the fillament.
I cleaned everything, there was some dust but not a big quantity so I don't think I was the problem.
I also removed the spring and the spring handle. I change the tension of the spring to be as low as possible. Then I reassembled every parts.
After that I have redone the bed level and the spring tension.
Compared to the first time that I change the spring tension, this time the gear to change it felt easier, there was less resistance than last time. Even so I changed the tension to the lowest possible each time.
After doing all that I printed the manufacturer print file, It was ok, there was no longer under extrusion. Then I tried multiple file of mine, which didn't print well before all that, this time it was perfect.
I think the real problem here was that some time ago I have disassembled the extruder and when I reassembled it I must have badly re-assembled it. Especially the spring part, since the feeling was different.


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Why does the ZAxis not move when I autohome when using the BTT as a probe and the SKR e3V3 image?
I have a printer with a v3.1 BLTouch and a BTT SKR mini E3 V3 and I can't get the BLTouch to work as a probe while homing. I have tried both of the images provided here and both cause the BLTouch to deploy properly but when I autohome and it gets to Z the BLtouch deploys (turns white) but the z axis doesn't move.
I found this thread which provides an image that does work but not much about how he got it to work and there are some tweaks I would like to make. So no matter what I try when I try to build the image myself the ZProbe seems to not work. This experience seems to mirror others in the thread.
My Current configuration I am building is available here
Does anyone know what other settings may be required to get a BLTouch as a ZMin Probe working with the newest version?
Also quick side question the docs say that the 3.0.1 build does not support BLTouch, does anyone know why?

According to your last GitHub commit you seem to got it working, please consider to post an answer and accept the answer after 48 hours for other to learn from this exercise. Maybe add in the question by [edit] how your Z-probe is connected, I suspect you are not using the Z-min endstop. It could be that the precompiled bin files expect the Z-probe not to be connected to the dedicated probe header?

Will do let me get things kinda of tidied up and I will put something together.

Basically I think that was the answer mixed with when I changed them and reflashed the eprom wasn't getting reset (which I just assumed it would). So things should have changed but didn't see it because it was still set to the old one.

That would be excellent! When cleaning up, look at the v3.0.1 version in the first line, it appears to be linked to the BLTouch but shouldn't it be v3.1?

Sorry finally getting back to answering the question. If this happens and your BLTouch is plugged into the Z-Probe you should make your Configuration file look like this...
//#define Z_MIN_PROBE_USES_Z_MIN_ENDSTOP_PIN
...
#define USE_PROBE_FOR_Z_HOMING
...
#define Z_SAFE_HOMING

This will tell Marlin to use the Probe instead of the endstop pins. Also in my case it was important to remember the EEProm does not seem to get reset when flashing the BTT SKR e3 mini v3. I think this is why when I tried flashing the other image it still didn't work. It would be my advice, if you are still having issues, to try resetting the EEProm as well.


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Material to use inside ultrasonic cleaner
I am trying to create a couple of holders for my ultrasonic cleaners. They are supposed to be used for parts that don't fit in the holder that came with the cleaners. I was wondering what material is best to use for this.
My initial thoughts are:

Material should hold up to the cleaning solution, I have a wide range of them from degreaser, deruster, and so on. I would say PETG or PLA should be a safe bet as it reacts with almost nothing
Material should not have issues with warm (not hot) water, I'd say something along the lines of 60-80 °C. This already eliminates PLA, but I think PETG should still be OK-ish (I am aiming more towards 60 °C than 80 °C).

Is there something I am missing? Does anyone have any input? I am anyway just going to do a few tests, but I assume starting with PETG is a good start.

ABS and PLA arn't very chemical resistant. PETG is better, but PET is probably your best option, however it is also a little harder to print in. PET also has a higher melting point than PLA, and shouldn't soften up too easily. PET is more durable as it tends to flex rather than crack, unlike ABS.

chemical ressistancy is dependant on what you test against. If you test with Hydroflouric ascid, nothing but PTFE is resistant, if you test with diluted hydrochloric acid, then ABS and PLA are highly resistant.

The materials you list suggests you could also print PETG.  PETG is probably you best option without having specialized options on your printer.

PLA is the easiest to use, but loses its shape at lower temperatures than your other options.  Moisture also makes it more brittle and more likely to crack sooner under ultrasound.

ABS is flexible (when thin) and survives temperatures as high as the boiling point of water.  But, it dissolves in acetone and isn't resistant to solvents.

PETG is reasonably flexible (also when thin) to survive the ultrasound and more chemical resistant, but somewhat harder to print as mentioned.

Printing PETG
PETG can have issues with the filament jamming.  If you print too fast, it jams because it doesn't have time to adequately melt in the nozzle.  If you print to slow, you get heat creep.  The solution I found was to use the maximum hot end temperature recommended, usually 250 °C,, and increasing the airflow through the heat sink and across the printer bed as much as possible.
One is tempted to leave the bed at room temperature to help prevent heat creep.  PETG will stick at room temperature. However PETG sticks too well.  Heating the bed to 80 °C will help the print release from the bed when it cools down.  PETG will also tend to damage the surface it's printing on.  Thus, a sacrificial layer such as a glue stick layer is useful to protect other layers on the bed.
Also import to the quality of the print for PETG, the filament must remain dry.  Moisture in the filament will cause bubbles in the print.  For your application the bubbles would make the print more porous, exactly what you want to avoid.  The best results is to print from a dry container and minimize the time the filament is exposed to open air over 20% relative humidity.
Keeping water out of the print
You may need to check if you can get enough exterior layers to keep the cleaning liquid from filling up the spaces in the fill.  People often use paint to seal the surface, but most paint is not resistant to solvents.  Thus, it would take socialized paint such as epoxy paint.  Paint will also tend to peal in an ultrasonic cleaner.

I added the paragraph about moisture in the filament because of the importance to your application.  "Printing PETG" is only a short summary.  There are many more details involved.

SLA printers don't print PETG. FDM printers do.

PLA and ABS also don't seem to be SLA printer materials.  I removed SLA.  Don't know where that came from.


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Diagnosing non-functional steppers (Ender 3)
I was upgrading my (already very modified) Ender 3 with a geared extruder, and figured instead of re-flashing the firmware, why not switch the extruder phase on the cable?  I accidentally shorted the two coils together instead of swapping within one phase, and now none of the stepper motors work properly (this is with TMC2208s on an SKR 1.4).
The current behavior is that when I try to move any axis (including the extruder), the motor will align with the nearest step (I assume) and then not move any further.
I'm trying to figure out if I trashed the mainboard, if I somehow managed to destroy all my stepper drivers with a single extrude command (which seems less likely), or if there is an easy fix I'm overlooking.

Turns out that resetting the board after reflashing the firmware fixed the issue.
(Then I dropped a spring on the board and totally killed it an hour later).

Sorry to hear you fried the board after fixing it. But, thanks for answering your own question, please accept the answer after 48 hours! Thanks!


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How to Print Food Safe With Replicator + and Z18? Three specific questions
I am working with a bunch of Makerbot Replicator+ printers and one Z18 in a classroom. I would like my students to be able to print cups and stuff to drink from if they want. I know I need a food-safe material AND a food safe nozzle if it can be managed.
So, I wanted to check the following:

Is there a material data sheet for the PLA filament that Makerbots use? I am told you need to check for each color, so the general one doesn't seem to be what I need. If anyone knows where to find it, please let me know.

I am told stainless steel nozzles are best. I saw several sold on amazon and the like that will supposedly fit the Smart Extruders. Recs on which I should use (if any) are welcome. Especially as the nozzle width will differ, the stock nozzle I think is 0.4mm? I assume I will need to adjust the settings on the printer as well anyway if I swap out the stock nozzle.

Another procedure my research yielded was that I would probably want to coat the 3D prints in resin. It seems there are several food-safe brands. Would such resins stand up to acidic liquids like orange juice and the like? What about alcohol? I know they won't work with coffee or something because PLA melts as such a low temperature. Recommendations are welcome here, and whether I should paint on or dip the 3D print?

3a. Even if the PLA isn't itself officially food safe would just coating it in resin solve that problem?
Any assistance here is much appreciated.

Why use PLA at all? Seems a terrible choice

It's what I have available. And with a Replicator+ it requires less fiddling about, but if there's another filament that I can use without too much of a problem in that particular model of 3D printer by all means tell me!

Printing food safe items is not safe or easy, and the results will likely not be durable or cleanable.  You'd be better off printing some of the thousands of toys and fidget widgets, and they'd probably print faster than a cup too.

FDM itself is not particularly food-safe, coating the print may prevent bacteria to settle in crevices. Furthermore, the filament should be able to withstand high temperatures for extended periods of time in case you want to clean the printed cups to kill bacteria.
An overview of food-safe filaments is given by All3DP. Without going into details, this overview recommends the use of certain TPU, nylon, high-temperature resistant co-polyester, PETG and ABS filaments. All these filaments are located at the higher-end temperature region of the filament pool.

Unfortunately the higher temp plastics (nylon, ABS in particular) emit toxic fumes when heated, so unless your 3d printer has a closed chamber with either filtered airflow or vented outside, it's differently dangerous.  PETG and TPU might be good alternatives though, but the heat resistance isn't that much higher.

A better alternative would be PETG, it's food safe on it's own and has more heat tolerance than PLA. It prints with much the same ease as PLA.
I'm not familiar with your particular printer, but nozzles are standard sizes. Swapping a brass nozzle for a stainless steel one doesn't need anything extra done. They both work the same, just the steel nozzle is harder wearing.

Brass contains lead, therefore it is recommended to use a steel nozzle. But, I'm not aware of studies of lead contaminating the print from the nozzle.

@ZeissIkon Indeed, but brass nozzles do wear, even with PLA, albeit not much, but they do. I don't expect that there are concentrations found like the Romans had in their wine...

Thanks I thought of PETG - I just wasn’t sure how well it would work in a Makerbot Z18 or replicator plus.

The amount of lead contamination from a brass nozzle is minuscule, even if your students ate kilograms of extruded filament. Stainless is better, but printed utensils from a brass nozzle are by no means unsafe.


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Random Line on some 3D prints
I have been having an issue for a while now with my 3D Print that one of the layers will appear thicker than the rest.
The line artifact will be on different height level. Also not all models that I would print would have this defect some will look pretty clean.
If I print the same model again the line will appear on the same spot. I tried with different filaments on the same model same thing again.
Is this maybe a slicer issue, anything that can help with finding the cause?
Printer CR-6 SE

I have tried different retraction settings same result.
I have calibrated the extruder and have changed the extruder to dual drive.
I am using a Micro swiss hotend.
Using 2.0 Cura 5.0 Profile from CHEP & CHEP 0.28 Fast Profile.
Linear Advance has been calibrated.

Here is some images of models that came out with no line present.

Hi Dave, welcome to 3DP.SE! If you suspect the slicer to be the culprit consider to use an alternative slicer. But, since you added an image of another print object with a similar defect at a different print height (my assumption) it would rule out an issue with the hardware (e.g. lead screw or linear guides). Please describe if the other defect is at the same or different height by [edit]. Thanks!

I suspect you have a defect in one of the Z-axis V roller wheels, or possibly in the lead screw, making it so that, at the point where the defect makes contact, the position is slightly deflected from where it's intended to be.

Thank you, I added some more info, the line height is different heights on different models. It will definitely be worth checking the wheels any way to diagnose a wheel? I know I can take off the screws and roll them a bit to maybe see if they are bent.

I am going to give Prusaslicer a go tonight will report back

Seems the issue went away using Prusaslicer. Spent the last two days trying to figure out new artifacts (pin holes on layer lines) after using a different slicer seems it was mostly retraction related. Producing beautiful prints once again. Thank you for the help.


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Ender 5 (not Pro or Plus) extruder motor port not working
I have a Creality Ender 5 (with CR Touch installed) and I just decided a few days ago to switch out my default V1.1.4 board with the new Silent Creality V4.2.7 motherboard (to make it silent and let me be able to install the CR Touch). When the package arrived, I immediately put it on my machine and flashed the firmware. Everything was going well until I realised that the extruder motor was going backward. I knew that it was the firmware’s problem based on other people's experiences which matched mine. I tried to do what they did which was switch the wires around. After that, the extruder stopped working.
I tried switching the wire of the extruder with the Z-axis on the mainboard. The extruder spins but the Z-axis stops working.
I concluded that it was the port's problem so I reached out to the manufacturer for a replacement. Even though they sent me the wrong version, the V4.2.2, The extruder port still didn't work.
I noticed when I switched the Z-axis wire to the extruder port and make take the Z-axis wire and plug it into the extruder, the extruder makes a "Thud" sound.
Does anyone know the solution to this? I have been struggling with this for 1 month now. Please help me solve this problem.

Did you heat up the hotend? Marlin is normally built with cold extrusion protection so that extruder motion commands are not executed unless the hotend is above a minimal temperature for extrusion.

I have. I always heat up my extruder to 215 degrees every time I want to test extruder.

If you unplug and plug stepper cables while the board is powered, you can kill the stepper drivers on the board. Always un-power the board when you replace stepper cables.

oh, so that's why... I guess i have to wait for the new board to arrive to get it to work. Thanks for your help!

I have got a new board and I got a new wire as well. I plugged everything in and the extruder stiffened at startup like it was supposed to but when I tried to make it spin, it refused to spin. it felt as if it went forward one step and back again. please help. I think it might be a software issue.