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Prusa i3 MK3S keeps clogging during print. Ugly streaks sometimes, and complete clog when printing with lower layer lines
The extruder on my Prusa i3 MK3S keeps clogging while printing. Loading is fine, and each time it clogs, unloading and loading the filament seems to work.
The filament extruded just after resolving a clog looks like it has small bubbled on it.
The problem only seems to happen when printing certain models. Printing the Batman symbol at 0.15 mm works every time. But the model I'm trying to print always fails at most a few minutes in.
I've tried cleaning the nozzle. Cold pull twice, and taken it out and heated it with my airgun and trying to work on it with the acupuncture needle.
The print that fails is this "Small Pill Container" with 0.1 mm layer height and 100 % infill, but printing a simple cylinder shape (25 mm outer diameter, 2.5 mm walls) creates the same problem. Trying to print them both at the same slicer settings with 0.15 mm layer height still fails.
The model was sliced using the newest version of PrusaSlicer 2.1.0 and printed with Prusament PLA at the factory recommended 215±10 °C, and tried 220 °C.
Any ideas what could be happening? Anybody experienced a similar issue?
Printing the bundled TreeFrog 50 μm sliced by Prusa for the Prusa I3 MK3S cased the same problem. Jam happened about 30 min in. I guess this rules out slicer problems as the root cause.

After a lot of research, it seems a lot of people have problems with the MK3 clogging, especially with PLA, and especially with prints with a lot of retractions. The issue seems to be the design of the heat-break, which has a throat between 2.2 mm and 2 mm, where the PLA can get stuck. I've ordered a new heatbreak. Please read this answer of my findings.

Sounds like a retraction problem. Use less retraction.

@user77232 The cura slice with 20% infill had the same retraction setting, and it's what I've been using for all the prints that succeeded as well, so I don't think that's the issue. Maybe it a combination of factor where retraction is one of them?

215 to 220 °C for PLA is pretty high, try reducing the temperature to 195 to 200 °C.

Tried, but with the same settings it still clogged. Although, I'm now printing it with retraction completely disabled. Though not a permanent solution, as it ends up stringing quite a bit on the first few layers, it might point to the root problem?

@user77232 Retraction was set at 0.8mm, and even printing it with retractions completely turned of, it still clogged. (Although it did get a bit farther)

Is the cooling fan working?

Jupp, and the heat sink does not get warm to the touch

Prusa Mk3 has a genuine all-metal hotend by e3d - which means it has all the all-metal problems, which means don't go overboard on retractions.

@Trish The retraction has been .8 mm on all the prints. And tried with retraction turned completely off as well(Loads of stringing, obviously, but still clogged during the print) And the problem also occurs with the preloaded TreeFrog test print file, which have the slice settings set by the Prusa team

Check your nozzle for damage, perform a "cold pull" and recheck the print - might be a damaged nozzle or residual chared filament

My problem was 2 things. The heatbreak, which was switched out for the MK2 version(Explantation below). And the Teflon Tube that runs down the heatsink.
Heatbreak
Change the heat-break to a generic E3D one. You can order the heatbreak for the MK2 from prusa, or any generic heat break for the E3D hot-end assembly.
On the Prusa i3 MK3(s), this component has been given a 45° taper in the middle, between 2.2 and 2 mm. This is done to ease filament retraction for the MMU, and will be nothing but problematic if you are not using the multi-material upgrade. Especially with higher nozzle pressures(eq. with lower layer lines), the filament may be squeezed into this taper, clogging the hot-end.
You may not experience full clogs, but partial ones that will show themselves as streaks in certain layers on the print.
Heatsink Teflon Tube
There is a teflon tube that runs down the heatsink. It's crucial that this is mounted correctly and it is not entirely intuative how.
First, press the teflon tube into the heatsink all the way to the bottom. Then, try to pull it out slightly. You'll notice that the small plastic ring at the top of the heatsink will pull out slightly along with it. Now, hold this black plastic part at it's current position with your fingernail, and push the teflon tube in the extra amount. When done, there should be no play in the tube.

The problem with low layer heights is that the filament flow is low, this means that the filament is at prolonged times at temperature, filament cooking can cause clogging. Try increasing the layer height to 0.2 mm to observe if the same clogging problems still occur, furthermore, try lowering the extrusion temperature.
Also, heat creep is a known issue (insufficient cooling of the cold end) to cause clogging. Note that this is unlikely on the Prusa MK3S, but you could check whether the fan rotates freely and that there are no additional obstructions in the flow path.
It could be that a combination of too much hotend temperature and a low filament flow is causing this issue.

I've tried setting the layer height to 0.15 mm, and the same problem occurred. Just for test I tried the batman logo at 30% speed, and it seems fine, so I'm inclined to belive that filament cooking is not the issue? Although I'll try it at 0.2 mm and report back to be sure.
I checked for heat creep, but the fan is running smoothly at full speed, with no obstruction, and does not seem hot.

@SomeNorwegianGuy Indeed we can rule this out in this case, but it was a possibility. I'll leave the answer in case others may find this question.

authors: Николай Елисеев


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What does the stainless steel plug do in the E3D Kraken cooler block?
In the E3D Kraken cooler block, there is a big, 10 mm grub screw, along the side of the cooler block.
I watched the entire Kraken assembly video:

There was no mention of this very thick grub screw. The E3D Kraken assembly wiki page may refer to this part as the "stainless plug".
Does the depth of the screw inside the Kraken heatbreak affect the effectiveness of the water cooling?
Why was it included in the design at all?
I'm asking because water frequently leaks out of this pore for me, ever since I had to repair some damaged tubing. Additionally I often have to use an extra fan when printing at high temperatures. I'm wondering, before I epoxy this grub screw into place, whether the amount it is tightened into the Kraken has some advantages or disadvantages.
The video shows the part already assembled on the Kraken. This is what the part looks like - it is much larger than the screws used to secure heat throats.

This stainless steel plug is necessary because of the fabrication of the cooler block. As this is a water cooled block, cold fluid flows in the inlet brass barb, and hot fluid out of the exit brass barb. The manufactured channel between the two is done through the hole that is later plugged by the stainless steel plug.
From the manufacturers website of the stainless steel plugs you can read that a tapered hole and sealant are required to make a tight seal:

They have a wide range of applications in sealing and require a tapered hole.

and:

Replacing these plugs on the Kraken should only be completed if you are confident in your ability to achieve an adequate seal. We use Threadlock and a measured torque setting.

Be sure the hole has a taper, if you over-tightened if once it may have worn. Epoxy based glue would be able to be used at the cooler block, temperatures are not expected to be too high, but from the comments below it becomes clear that there are specific sealing products available for sealing the plug other than epoxy.
The depth of the grub screw is not likely to affect the cooling properties (it isn't expected to block one of the brass barbs).

Loctite 243 Pipe & Thread Sealant Liquid would be better, as it has a very wide temperature range (-55°C - +180°C). https://www.henkel-adhesives.com/uk/en/product/threadlockers/loctite_243.html

The connecting channel between the two brass barbed hose fittings needs to be drilled out.  To open that channel, a hole is drilled into the side to connect the two top holes (which have the brass fittings screwed into them).  The hole doesn't need to penetrate both sides, but it must get through one side.
The grub screw seals the hole.
Instead of using epoxy to seal in the screw, you could use the PTFE (Teflon) white plumbing tape.  It is specifically designed to seal threads.
If I remember, you can thread it in as tightly as you like.  It won't interfere with the water channel.
I have a Kraken, and I looked at how to make another one.

source: Stack Exchange

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

authors: 北京做假证_北京办文凭毕业证 - spam

sort: votes


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The first screen of Marlin 2.0 is showing some horizontal lines, appearing to be broken
We are using the branch bugfix 2.0 and the first screen of Marlin is showing some horizontal lines, appearing to be broken.

After 3 seconds, the boot screen appears and everything works normally.

We have tried to disable the custom bootscreen:
//#define SHOW_CUSTOM_BOOTSCREEN

We have tried to disable the Marlin bootscreen:
//#define SHOW_BOOTSCREEN

We have checked the power supply.
We have wrapped the "flat cable" in aluminum foil and ground everything correctly.
We have deleted the "firmware.bin" and it did not solve the problem.
The first time the firmware is loading the "firmware.bin", those horizontal lines do not appear, but when it is loading the "FIRMWARE.CUR" it does appear.
What exactly is happening? How do I fix those horizontal lines on boot?

So I take it your questions are probably, What exactly is happening? & How do I go about resolving the problem? The reason I say, is, you really didn't specify a question in your ... er ... question. Could you please clarify what you're trying to figure out so we don't have to assume?

Seems to be normal for now. Both my SKR 1.3s running Marlin 2.0 do this.

Any other idea on how to solve this? It seems to be a problem in the bootloader routine.

Something is causing your screen to get signals to display that before your board properly takes it over after 3 seconds.  It is an oddly repetitive pattern.
If it is software, you should not see it on a stable stock marlin release with minimal customizations to enable the LCD.  Usually nothing else shares pins with the LCD, but please do double check pin assignments.
Beyond software lies a realm of hardware issues:
Issue could be due to bad wiring or wires running in areas where they are picking up noise as the system boots up; LCD ribbons are not particularly noise resistant.  I say wiring but it could be anywhere along the circuit, including circuit boards.
There is also some (smaller) chance that your power supply is providing the noise at the initial boot up in which case you may be able to resolve it by adding capacitors to stabilize the DC voltage.  Not sure what check you already did of the power supply, but a DC (RMS) reading may not show anything strange on a regular multimeter even if there is a strange AC signal.

We have checked the LCD ribbons, and other hardware possibilities. It seems to be software. The first time the firmware is loading the "firmware.bin", those horizontal lines do not appear, but when it is loading the "FIRMWARE.CUR" it does appear.

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


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Painting Text on Model
For a model that has raised text on it, how do go about painting the very top layer of text, to make it stand out from the background? Lets say I printed the whole model the same color, what type of paint would work well, and not get on the background too?
Here's an example of a model that has raised text: https://www.thingiverse.com/thing:3025280

Use a firm (as opposed to spongey) roller..?

You don't provide any dimensions or sizes, but...
Assuming that the text is sufficiently elevated from the rest of the model, you could use a firm solid (as opposed to soft and spongey) roller, of an appropriate width.
This should enable you to paint just the text without getting paint on the rest of the model.

If the text is small and in a "valley" or groove, then a narrow roller would be required, in order to avoid the surface either side of the text.
If the text is not on a flat, or smooth surface, then a small diameter roller might be required.
If you can't find a tiny paint roller, you could jerry-rig one using a paper clip and a roller wheel from an old cassette tape

The technique you look for is drybrushing and not dependant on a specific type of color, as long as it can be applied with a brush.
An alternative technique might be carefully applying glue and leaf metal.

I recommend to print stencil for the text. Basically flat thin plate with text holes in it. Just cover your model with it and only text will be painted through the hole. In this way you could do it rough, fast or like Mr Bean did.


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Best material for compression?
I'm designing a mount for a cylindrical speaker to attach to my bicycle. It will mount on the bottle cages. I've printed a few iterations with various infill settings (using PLA) and the weak point is always the bolts holding the entire mount to the bike. They can't handle the compression needed to secure it properly. I had thought about using an imbedded metal part to distribute the load, but it's not easily replicable and I want to make the design public and fairly accessible to others with the same speaker. I currently have PETG and ABS, would one of those perform better or should I order a specialty high strength polymer?

Welcome to 3dPrinting.SE!

it might not be a material but a design failure. Can you show how you orient the part in the slicer, and how you set the wall thickness and infill?

I'm at work at the moment, I can upload some pictures when I get back home. It's a strut about 100mm long, on either end is a 74mm loop perpendicular to the strut. It's printed with the strut vertical, I'm just realizing that that's probably a major weakness. My priority was to keep the layer lines running along the loops so they wouldn't break when clamping down, but that means I'm bolting the strut against it's weakest axis. I feel like a goof, that's really obvious.

You can have "Different infill in the same part" to locally reinforce the structure to prevent compression of the structure. A picture of the part would help a lot!

Also, TPU would be perfect for something like this.

What @towe said. Try TPU with high infill and wall count so it's mostly rigid. It will be indestructible.

Related: https://3dprinting.stackexchange.com/q/11657/2338

Infill has minimal effect on the strength of printed parts, so I would expect the part to break in the same spot regardless of what infill percentage you used.
PLA is especially poor in this exact application, and it undergoes significant creep/cold flow under mechanical compression over time, so even if achieved the necessary strength by changing settings (which you can), it would require that you periodically tighten the bolts more and more, as the PLA would slowly deform under the mounting pressure.

Perimeter width and number of perimeters are what primarily influence the strength of a printed object, infill has very little impact on strength in comparison, and unless you're using an exotic pattern like gyroid, what impact it does have is not even close to isotropic (will add strength in some directions while doing nothing in others).  But even then, infill only really has an effect when we are talking about forces that are spread evenly over the entire object, not concentrated strength of a specific spot of the part.  And that effect is always much weaker than what perimeter count or width will have.
Just bump up your perimeters to 4 or even more and that should make a huge difference.
And also, don't use PLA.  I think PETG is a much better choice in this situation.  It is more ductile only slightly less rigid than PLA, making it much more durable overall than PLA, and less prone to cracking under compressive forces.  PLA theoretically has higher tensile strength, but that often doesn't mean much.
I would not recommend ABS, it tends to have similar issues with brittleness and is one of the weaker materials one can 3D print.
It terms of ordering a special high strength polymer.... unless printer and hotend is rated for in excess of 400°C, no such 'high strength polymer' exists, at least not that you can print.  PLA and PETG are close to the best you can get, with Polycarbonate inching out ahead but not by a huge amount (~20%).  Despite what filament companies would like you to believe, carbon fiber reduces the strength of PLA, ABS, PETG, PC, and probably nylon, and instead simply makes those polymers more rigid and increases dimensional stability.  The only filaments that would actually be made stronger with added fibers short enough for filament manufacturing processes are ones with glass fiber.  But you don't want to print those filaments, trust me.  They will dull the teeth on your hobbed gear(s), even if made from steel, and will just ruin all but ruby nozzles very very quickly.  And they still wear out ruby nozzles even then.
There are exotic polymers, but none of them print at less than ~350°C, and are generally exceedingly expensive.  All the polymers that can be used at normal printing temperatures are all fairly similar to each other in terms of tensile strength at least.

I realize this is an old thread but I’d still like to share some thoughts for others who may find this post.
If I understood correctly, you were printing this part in to see shape You were printing this part in a C shape. Loops horizontal, strut vertical. Yes, that will produce a very weak strut that is likely to split open when tightened.
Next option is to print it in a U shape. Now you have a rock solid strut that will sustain compressive strength from bikts much better but depending on thickness and forces, your loops at the end may be prone to fail.
You may want to consider designing this in three parts, strut plus 2 loops, that you glue together. I know glueing doesn’t sound very sexy but 1) each part is printed with optimal strength, and 2) glues like Weld-On produce incredibly strong bonds, as strong or even stronger than inter-layer printed strength.
And lastly, it may also help to use overdimensioned washers on BOTH sides the strut to spread the compressive force of bolt and bike frame and prevent splitting.

I actually ended up doing something similar to that. Originally tried printing all in one part, two parallel rings joined by a rectangular strut. Decided to separate the strut and print them all flat, so the layer lines are aren't inline with the dress when mounted. Joined both rings to the strut with M3 bolt's. Can happily report it's been working for three years no problems. :)

For your particular application, you should be able to get something acceptably strong with PLA as long as you design it right - both the model itself, and the way you slice it (orientation, number of walls, etc.). metacollin's answer covers this pretty thoroughly. Using PETG could be an improvement, if you're willing to spend time learning how to print it right (if done wrong it's super-brittle).
However, as towe suggested in a comment, I'd give TPU a try. When printed with many walls or with high infill rate, TPU can be fairly rigid, and there's no way you're going to damage it with a bolt unless you just keep going after it's already tight. It's a relatively easy material to work with, and pretty much any printer that can print PLA can print TPU (although you may have to slow it down quite a bit) so it meets your requirement of being accessible to others with the same speaker.
(Note to self and others: it'd be a neat experiment to take a torque wrench to a bolt with metal washers through a solid brick of TPU and see how much it can take before it fails, and how it fails when it does.)

Try heating op your PLA while mounting it. The PLA wil temporarily weaken and will become a bit moldable. PETG is a bit more brittle than PLA is my experience so I'd say stick to PLA. Otherwise you might try Arnitel ECO. I can try to find an amazon purchase link for you if you want. Anyway, it is more rubber like and stays flexible, it will never crack but depending on your design it might become a bit more wobbly. If you share a picture of your design or an STL i might be able to help you a bit better.


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Efficient way to create a "mold" of a solid object in Meshmixer?
Currently I have a model of a fingertip finished in my project, however, I would like to create some sort of "cap" that if printed would fit on top of that finger. Is there a good way to achieve this in meshmixer?

Surely! First of all, a mold is, simply put, the negative of the item. So we need to make such a negative and give it some thickness. I have this funnel model...

We start Meshmixer, import our funnel and then go into Meshmix and pull a cylinder into the frame. We size and align it to hide the funnel but for a tiny part at the top (or however much you need to have covered in the mold)

We click the cylinder, press SHIFT and the funnel top. In the top corner a menu pops up:

We choose "Boolean Difference", the menu changes to show this:

Next we alter the Target Edge Scale till we see the top corner (0.6 seems to work) then accept. The result is this mold:

But that's a REALLY snug fit at this moment. 0.0 mm space. We can use that to cast our funnel... but we might want to make this a box for our funnel or we know that our casting material shrinks some 4 to 5 % when curing. So we need some space in the mold or box. So we need to shift the faces some. What happens to holes if we scale the whole thing up by... say 5 %? They become 5 % larger of course! So let's just do that!

Edit
Transform
hook Uniform Scaling
pull X, Y and Z out by 1 mm (which happens to be 4 % in case of a 25 mm item.)

Use those square boxes marked with green dots to pull

Accept and... DONE! Last to do: export as STL and here you go! a Mold that is 4% larger and could be a cap for the funnel.


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Octopi connecting just once to wifi
Just starting with octoprint.

Bought a pi3A+,
Etched a 4Go micro sd card with the latest octopi distro (0.17.0)
Using a 5V bench power supply that delivers up to 10A.
Following official octopi instructions

I managed to connect once my pi to the wifi, configured it, but as soon as I reboot my pi, it won't connect to the wifi again.
Any hints?
Nothing helped me in the wifi troobleshooting FAQ.
I thought that I changed a particular config but :

without configuration change, I:

started the pi once
waited until the pi connects to the wifi
successfully pinged the pi via my PC
rebooted the pi
a new ping wouldn't work

I compared the files on the boot partition and only this changed:

freshly etched sd card:

cmdline.txt:
console=serial0,115200 console=tty1 root=PARTUUID=6c586e13-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait quiet init=/usr/lib/raspi-config/init_resize.sh

card from rebooted device:

cmdline.txt:
console=serial0,115200 console=tty1 root=PARTUUID=6c586e13-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait

there is no more differences.

Welcome to 3dPrinting.SE! It sounds to me as though you inadvertently changed the WiFi settings. I'd go back through them and ensure they are now setup correctly. Don't assume everything is set right, make sure they are set right.

I checked the octopi-wpa-supplicant.txt and it is unmodified...Which fil are you talking about? I even tried to change the wifi settings in the raspi-config

I'm not entirely sure as I'm not familiar with those settings for either you pi or the computer you're using. What I'm getting at is something you changed when you configured your pi has caused the WiFi to stop connecting. Go back to those changes and you'll most likely find the issue.

see my edit, what can i do i just the reboot change the config?

What worked for me:

changed SD card from 2 GB to 16 GB (do not need so much)
power the pi with 5.4 V instead of 5 - 5.1 V


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Smallest dot/dot indent for Prusa MK3S using PLA
I want to make a project involving many small dots indents and I would like to know how I can calculate the smallest dot hole the Prusa i3 MK3S can extrude around on a layer using PLA. In other words, if I printer a mesh with circle shaped holes, how would I know the minimum diameter of the holes. Is it simply the same as the layer resolution (0.35 mm), filament size (1.75 mm), or is it something else?

Welcome to 3dPrinting.SE!

There is no direct limit on the size of a hole in XY-plane (that means: oriented so that the hole is visible from above).
The movement accuracy of MK3S (and most other modern 3D printers) is about 0.01 mm. So theoretically you could move around a circle that has diameter of the (default) 0.4 mm extrusion width + 0.01 mm, and get a 0.01 mm hole in the middle of the circle.
In practice, the hole size will be limited by the repeatability of the extrusion width. If in the above example the extrusion width happens to be 0.41 mm instead, there would be no hole remaining.
On a well calibrated printer, 1/4th of the nozzle size should be manageable, i.e. for MK3S you should be able to get 0.1 mm holes quite reliably.

That depends on the ability how fast you get filament to stick to the build plate and whether the filament is loaded in the extruder. It also matters which size of nozzle you are using. The filament diameter has no influence other than smaller filament width (e.g. 1.75 mm) requires more length to extrude with respect to thicker filament (e.g 2.85 or 3.0 mm), and is therefore more precise to lay down (on the other side is the deviation on the filament diameter, i.e. manufacturing tolerance, larger than for thicker filament...).
If it does not stick you need more length, also, if the filament is not preloaded enough, the nozzle chamber needs to be filled first. Note that the printing of several small circles is a challenge, see e.g. "How do I get circles on small interior holes to adhere to the bed?".

Thanks for bringing this issue to my attention (I don't even have the printer yet so this is really helpful to consider). It would be a possibility to start with full layers and sand them down. Would that possibly help?

@curious I'm not a big fan of sanding, but it could work depending on your application. When you get the printer, start experimenting what works and what not, for questions, there are plenty people around to help you get the answers. Good luck!

The only way to know exactly what limits your model, printer, slicer, and filament operate under, is to test it. While we can provide some guidelines, actual performance varies on a complex set of inter-connected variables. Even the room temp/humidity, filament age, and even filament color, can matter at the tightest margins. You have to consider what the print direction for the holes is (z/x/y), as layering matters even more than the above. And under what print speed and layer height? There's billions of combinations just with your printer alone.
Bottom line: run some test prints and see what you're satisfied with.

Let's look at how small we can print, shall we? Well, we have this filament, it gets pressed into the chamber, melts and then moves out a small orifice. So the first thing that limits print minimum is nozzle diameter, which correlates with the extrusion width - usually, I use a factor of 1.1 nozzles for the extrusion width.
Next factor is the bed or surface you're printing on which correlates with the Print material: some surfaces literally love to take your filament and allow your printer to extrude just a dot, then lift up like PLA onto a well-prepared surface. Others REALLY don't want to stick, demanding you to extrude more, which means you need to draw a circle (POM).
A lesser factor is the print temperature, which changes how vicious the filament is and how well you have dialed in your retraction, which determines how much of a "dead" move you have to have on the extruder to get the filament to extrude between dots.


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Printing 2x slower after upgrading to "MarlinTarantula" firmware
I have a TEVO Tarantula printer, recently I have upgraded it's firmware from the stock firmware to marlin 2.0 using this configuration repo.
Since upgrading my prints take 2x the time they used to (and the time Cura says they should take). I have tried to increase the printer's acceleration and jerk maximum configuration, but it did not help.
In addition, another symptom that is new is that whenever a straight line is printed (for example an infill line) instead of the motors moving in one swift motion, I can see (and better yet, hear) them moving in a different speed. Specifically, it looks like the motors slow down midway and start again.
How can I address those issues?

Also if your Marlin 2.0 is using junction deviation (new default) then jerk settings may be ignored. Default JD amount is equivalent to extremely low jerk. JD still seems to be buggy so I'd switch it off and go back to classic jerk.

First, Ultimaker Cura estimated printing times are not necessarily accurate for non Ultimaker printers. For Ultimaker printers this is perfectly tuned, Cura estimates the printing times from experience for the UM3E correctly. Please look into question "How to determine real printing speed (tarantula/cura)?" which is relevant to this question and has an interesting accepted answer.
Second, changing the MAX accelerations will not work, you should increase the default acceleration:
From the TEVO Tarantula Marlin fork you read from the Configuration.h file:

/**
 * Default Acceleration (change/s) change = mm/s
 * Override with M204
 *
 *   M204 P    Acceleration
 *   M204 R    Retract Acceleration
 *   M204 T    Travel Acceleration
 */
#define DEFAULT_ACCELERATION          1000    // X, Y, Z and E acceleration for printing moves
#define DEFAULT_RETRACT_ACCELERATION  2000    // E acceleration for retracts
#define DEFAULT_TRAVEL_ACCELERATION   3000    // X, Y, Z acceleration for travel (non printing) moves

From the main Marlin source you will find:

/**
 * Default Acceleration (change/s) change = mm/s
 * Override with M204
 *
 *   M204 P    Acceleration
 *   M204 R    Retract Acceleration
 *   M204 T    Travel Acceleration
 */
#define DEFAULT_ACCELERATION          3000    // X, Y, Z and E acceleration for printing moves
#define DEFAULT_RETRACT_ACCELERATION  3000    // E acceleration for retracts
#define DEFAULT_TRAVEL_ACCELERATION   3000    // X, Y, Z acceleration for travel (non printing) moves

The TEVO Tarantula sources have lower default acceleration values, you could try to increase those.

+1 - since EEPROM settings are enabled in this firmware, you'd probably want to M502 M500 to clear the previous settings out.

@towe - You suggested a "+1" but never voted? I would hope you can fix that! :o) Voting is essential to the well being of this and every Stack.

I'm sorry it took me so long to respond. I have implemented your suggestions, and also matched the Jerk settings to the original Marlin repo. My prints are now 'only' 50% slower than what Cura predicts.
Do you have any more ideas about what can I adjust?


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Building 3D printer: LM8UU bearing can't fit into
I'm new to 3D printing and I'm learning how to build my own 3D printer.
I bought polymer LM8UU bearings and I'm trying to fit onto a rod of dimension: D8 mm * L300 mm. Sadly it doesn't fit, I was wondering if I would need to buy new rod?
If so, what size of diameter should be used?  General guidelines I need to look out for are also appreciated?

Welcome to 3D Printing.SE! Please explain if the bearing does not fit into some cavity or onto a shaft, that makes a big difference. As it is asked now it looks like the 2 are not compatible. My comment got too big to fit, so I posted an answer that also addresses fitting into something, hope this helps!

Bearing on a shaft
An 8 mm (ID, Internal Diameter) bearing should always fit on an 8 mm (OD, Outer Diameter) shaft. If it does not fit, one of the 2 is of a different size. Please use a caliper to determine the size of both.
Bearing in a housing
If it is the outer size of the bearing, i.e. fitting in a printed carriage or a bearing housing (e.g. SCxxUU), you should be aware of the different sizes of polymer bearings. E.g. there are RJMP-01-xx and RJ4JP-01-xx types of polymer bearings (xx denotes the shaft diameter, e.g. 08 for 8 mm shafts).
For RJMP-01-xx bearings (not compatible with LMxxUU bearings):

// Parameters for RJMP-01-xx (shaft size xx, all dimensions in [mm])
// Designation  d1  d2  B   B1      s   dn
//-------------------------------------------
// RJMP-01-08   8   16  25  16.2    1.1  15.2

For RJ4JP-01-xx bearings (compatible with LMxxUU bearings):

// Parameters for RJ4JP-01-xx (shaft size xx, all dimensions in [mm])
// Designation  d1  d2  B   B1      s   dn
//-------------------------------------------
// RJ4JP-01-08  8   15  24  17.5    1.1  14.3

d1 is the inner diameter, d2 the outer diameter and B the length of the bearing
The RJ4JP-01-08 bearings are drop-in replacements for the LM8UU linear bearings. Note that the RJMP-01-08 have a larger outer diameter and do not fit into the regular bearing housings. The increased thickness gives the bearings more rigidity.


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Filament Variation Detection
I'm trying to find out how "normal" filament (not super expensive filament) varies in diameter (or more accurately cross sectional area) over the length of the filament. I've looked around and the only thing I can find, that many filaments are sold with the tolerances, not how "fast" they vary along the filament. A +- 0.1 mm over 1 meter is after all qite different from the same alteration over 0.1 meter.
I am mainly interested in this, as I want to build a printer with very small Z-height steps, thus a small variation in the filament diameter will lead to a rather large variation in the extrusion width. While I thought over the project, I came to the idea of using some kind of capacitance measuring device to detect the cross-sectional area, however it is only possible (or rather feasible) to measure the average cross-section over a rather long section (10cm+). Hence main part of the question: How "fast" does the filament change diameter?
The other part is obviously: Are there other (cheap) ways to measure the cross-section? I could use light, but then I would only get the diameter at one point (pretty sure the filaments aren't perfectly round) and using multiple sensors would quickly become expensive. And then there's the issue of transparent filaments. Most mechanical solutions have the same issue, only measuring one point and might have issues with certain types of filaments such as very flexible filaments.

Marlin is capable to adjust the extrusion multiplier based on diameter measurements, sensors exist for this feature. I believe you need to input the length of filament path of the sensor to the nozzle. I have to look it up, is this something you are after?

Yes, this is basically exactly whay I am after!

@0scar looks like all the commercial sensors (at least the ones I can find) are optical sensors (either actuall cameras or ”strip cameras”) which look rather expensive :( I’m looking for very cheap sensors (hence the idea to use capacitance, which can be measured cheaply)

a loop around the filament could expand and contract as width changes in any direction. if that loop has tension, it can be measured. i think sampling 4 diameters (90 deg each) would give a pretty good estimate.

another precise measure can be make with a lever; the end closer to the fulcrum pinches/hugs the filament, which causes large moments on the other end of the lever when that distance changes. those large movements can be measured with a hall-effect sensor from a magnet on the lever; a clothespin for example.

@dandavis A loop suffers the problem of only measuring the circumference, so you still don't know the area. The "lever" solution is probably the one I am going for, but using light detectors at the ends instead of "expensive" magnets and hall-effect sensors. (Expensive relative to photodiodes and LEDs).
Also, I think you mean 45 deg increments for measuring the diameter :P

@dandavis Though you did give me one idea I might be able to use :D If the magnetic permeability of PLA (and other filaments) is larger than 1 the magnetic field strength of a coil with the filament in it will be different depending on the cross-sectional area of the filament. If I place a very sensitive hall-sensor inside the coil I might be able to measure those differences :D Now I just have to find the magnetic permeability of PLA :P

@dandavis Ok,relative permeability of plastic is way too close to 1 to be able to measure. Just saying this to save anyone else who might see this suggestion and want to try it some time, doesn't work :(

You would want a thickness gauge with the ability to communicate via serial. Once you managed to modify Marlin to talk to it, and you engineered a system of rollers for the filament to pass through, then you could automatically compensate for the thickness of the filament.

https://www.amazon.com/Neoteck-Digital-Thickness-Electronic-Micrometer/dp/B07Q33RSH6?th=1

Yes, a mechanical solution is one way of doing it. Though a thickness gauge is very expensive (looking for solutions where the hardware is under 2 dollars or so). This also doesn’t adress the main question of how ”fast” the diameter changes, but thank you for the suggestion :)

@BeaconofWierd analog Feeler gauges that are accurate for Thou(sands of an inch) are available for as little as 20 bucks for a decent one. Mounted in the right way, and dialed to thickness, you'd see the current variation from the target at the measuring spot. It would be an effort of picking up the data for a long measurement continuously.

@Trish The hardware which isn't 3D printed on the current mechanical system I have for measuring distances costs around 50 cents (basically two leds and two photodiodes) and can measure distances down to 0.015 thou, so when it comes to a mechanical system I'm fairly sure I can't go lower than that (Note, the 0.015 thou is the theoretical limit, practically I'm getting around 0.1 thou). Also, this mechanical system has the limitation of only measuring diameter, not cross-sectional area.

@BeaconofWierd 2 LED/Photodetectors will give you a good estimate, assuming an ovaloid. If you know the exact distance between, you can use A=a b pi. If you match the data pickup with stepping (like, trigger a pickup every mm of movement) and write the data into a CSV, then take the distance between the sensors into consideration (if you don't measure in the same spot), you could use a spreadsheet to measure the whole filament... knowing the lead distance, you could arguably write that data to another CSV as percentages... which could be fed into the printer via M221 accordingly.

@BeaconofWierd, $2 dollars!? No, there is nothing that you can use to measure the filament thickness at that price point. Even the $2 dollar multi touch needed an expensive web cam and computer.

@user77232 I just told you what I am currently using to measure distances, and that setup costs less than 1 dollar, so there are ways to measure the thickness for less than 2 dollars, I’m just looking for alternatives to make sure I haven’t overlooked some well known cheap way to measure filament diameter.

@BeaconofWierd, No there isn't Distance, in your case, just requires a tachometer; which is relatively simple. The task of measuring thickness to an amount that you can do something meaningful with the information, requires a sensitive instrument with a high signal to noise ratio. For 7 dollars you could get a force sensitive resistor mounted on bearings and that would still cost you more than the above mentioned technology to implement.

@user77232 No, I'm not using the diodes as tachometers, I'm using them to sense how much light is blocked and from that I can calculate the distance the thing which blocked the light travelled. Think two small slits which can move relative to each other, when they are perfectly aligned you have a maximum signal, when they have moved the length of the slit you have no signal.


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Diamond hotend with single extruder motor
Today I started to google the idea of multimaterial printing. I checked out prusa multimaterial upgrade and while it looks nice, it is expensive and will not probably work with my non-prusa printer.
I discovered there is Diamond hotend, which allows for 3 (or even more) colors at the same time. But everywhere I checked, one extruder motor was used for each color. Since my MKS Gen L motor connections are already all used, I was thinking if it would be possible to handle all of the filaments with single extruder motor.
Basically the motor would have long shaft which will cover all filaments, and I would add some servo that would push a pulley against the selected filament.
I think I would slice it as a multiple hotend setup and then postprocess the gcode in a way, that when tool is changed I would add custom command that would push the pulley against appropriate filament.
I would either need a servo for each of the filemants, or maybe with some clever mechanics one servo in different positions could do all of them.
I am just curious if you think this would be possible to do, since I did not find anyone discussing this idea. Probably because it will require adding custom commands to the firmware.

Sounds a lot like the MMU concept - which is available online for you to build yourself.
As for the diamond hotend and your board, it might be easier to have a look at the Klipper firmware and just use two boards.

I did not find any information about how to make the MMU, just $300 to buy it.

what you describe is a variant of the Prusa MMU2 but with triple the bowden tubes and a hotend about 2-4 times as heavy.

You might save yourself a lot of engineering by copying the Prusa MMU2.  Here is a github project for someone doing exactly that:  https://github.com/cskozlowski/mmu2
If you look on Prusa's web site, you can find printable parts for the MMU2.

I also noticed that new version of Marlin includes the support for the prusa MMU2, so maybe this is the way to go... except I still have to solve how to control the additional motors....


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Smaller outer layer height?
I am printing minis and other very detailes stuff and I find that 0.04 mm layer height gives the best looking (smoothest) result. However it takes a long time, so I am looking for ways to speed it up. Is there any slicer which offers different layer heights for the outer perimiter? So you can print your model at 0.12 mm or so, but the outer layer gets printer first 3 times at 0.04 mm?

you can easily smooth the surface of ABS prints, which would be much faster. to answer your question, afaik, each entire plane must be printed as a single height.

@dandavis Acetone smoothing doesn’t work well for minis (faces and small details completely dissapear). And each plane only has to be printed as the same height to avoid the printer head colliding with previous lines, if you print the perimiter first in smaller heights and then the rest at normal height you don’t have that problem (It would be the same as printing perimiters first)

@BeaconofWierd I would open a feature request ticket on all Slic3r, Sli3r Prusa Edition and Cura github pages. That feature is not available as we speak in any slicing software I know of. Post a comment with the links to the tickets after you have done it, thanks.

@FarO Oh, apparently this was already a suggested feature Cura basically turned down :( https://github.com/Ultimaker/Cura/issues/6322

"Good,  Fast,  Cheap.   Pick any two"  applies here, I fear

In Ultimaker Cura, unless you print a single perimeter outline and add extra wall infill support you are not going to have different outer perimeter layer heights.
However, Cura is able to reduce the printing time, E.g. you can have fine layers for the wall (all perimeters), and coarse layers for the infill. The option is called "Infill Layer Thickness":

Infill layer thickness
Since the layer height of the infill is not important for visual quality, you can use thicker layers on the infill to reduce the print time. When adjusting this setting, always make sure that it is a multiple of the layer height, otherwise Ultimaker Cura will round it up to a multiple of the layer height. This means that you can, for example, print with an infill thickness of 0.2 mm while the layer height is 0.1 mm. The printer will first print the walls for two layers, and then it will print one thicker infill layer.

Note that this is not a standard option, you need to put Cura in the "Custom" mode and filter/search for the option using the search bar. Below you'll find the upper right corner of the Cura Graphical User Interface where I searched for the option:

Note that there are 2 options, one for regular infill of your product and one for infill of the support structures.

An other department at work is working together with a start-up university company to 3D print PEEK molds (from pellets) using 2 nozzles/extruders (to create resin injection parts), one has a large nozzle, the other has a fine nozzle. They use their own developed slicer software to use the fine nozzle for the outer contours and the coarse nozzle for infill and support. It could be that they developed this because it was not available in commercial slicers. For the 2 most common free slicers, Cura and Slic3r, there is no option to have just the outer perimeter of different height than the inner perimeters. If you think of it, it is also pretty difficult to execute, you either get:

(which does not improve the quality of the product, it will make the outside more coarse) or you'll get gaps:

Note that both upper images do not include infill, only 1 outer and 3 inner perimeters. The image below is probably what is possible with Cura, so all perimeters the same; green is infill now:

@0scar That setting is very useful, however it’s not exactly what I am after. Infill is usually a minority of the print time, the majority is the outer walls (at least for many of my prints). I’m looking for a setting which allows you to adjust only the outer perimiter wall to a shorter height while keeping the other walls right next to the outer wall at an increased height.

@BeaconofWierd set 1 perimeter and 100% concentric infill

@Trish 100% infil will cause the print to take a lot longer than just having all walls at fine detail. It also wastes a lot of plastic.

@0scar oh, so there’s a start up working on this :D maybe we will see it in slicers next year then :)

Not what you want but may still be helpful.
PrusaSlicer allows the layer height to be varied along the Z-axis so that you can have more detail in bands where it is needed, and less where it is not.
Since infill is not your time consumer, you may not find the "combine infill every n layers" helpful.

Isn't this called adaptive layering or something? I think Cura has a similar feature.


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I need assistance replacing the PTFE tube in the nozzle on our Flashforge dreamer
We disassembled everything in order to unclog the filament from the tube, but now I can't seem to get the nozzle to screw back in to the hotbed with the PTFE tube in place. Is there some kind of trick? I feel like if the tube were slightly smaller in diameter it would work. I'm using the same tube, just without the filament that had clogged it. Am I just not using enough force?

The PTFE-tube usually passes some kind of clip or clasp that allows it to only wander in one direction.

Does this answer your question? How do I get a replacement PTFE tube to fit inside my nozzle?

Do you mean hotend and not hotbed?

Carl - I did indeed do several searches for how to do this - which is how I ended up on this page. I have not been able to find an answer, which is why I posted. The page that you linked to, doesn't actually answer the question and was not of use to me, which is why I posted my question with details and a picture.

I was able to fix my problem so thought I'd post how I solved it for anyone else that is looking for a possible answer:
I believe the actual problem was that there was filament hardened inside the nozzle which I couldn't see, so that prevented me from being able to push the PTFE tube into the nozzle deep enough. I reassembled the extruder and heated it up, then using needle nose pliers so I wouldn't burn myself, I held the nozzle to the end to block to heat it up, (I didn't actually screw it in) and the stuck filament melted so I could scrape it out. I also learned from Tang, the Amazon flashforge tech guy, that the tube should be 23mm above the block, so that was helpful to use as a guide. As I read in other places, I then inserted the tube into the block to heat it up, which I think made it slightly more pliable and easier to insert into the nozzle.

It is perfectly fine to post an answer on your own question! Thanks for sharing your solution!

I got the same issue before. When you tried to push out the material from the tube, one end of the tube was being pressed. The tube was so soft that the diameter at that end was slightly increased. Hence it was difficult to put the tube back. When you tried to tighten the screw, more force applied and the tube end was pinched more. I got some spare tubes from the supplier. I simply replaced the tube. The PTFE tube could be pulled off from the nozzle.


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Ender 3 with slic3r causes the head to go off the bed
I just downloaded slic3r and setup my settings on it, but when I sliced and started the print, the head went off the bed and then tried to print. It doesn't matter what I set the origin to, it still does the same thing. Does someone more knowledgable with slic3r know how to fix this?

did you define the offset of the home-switch position to the corner of the bed?

Do you mean the origin?

Please post screen shots of the build plate settings. Also state printer type or bed size. You can get some more information from this question.

Did you set slic3r with the correct print volume dimensions for your printer?

Yes I did, I also said it was the ender 3 (220 220 rectangle), and that it didnt matter the build plate settings, it always did the same thing no matter what settings it had


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Weird temperature graph and thermal runaway protection triggered
I woke up this morning with my 20 hour long print failed around 15 hour in. I checked the octoprint console, and saw a very weird temperature graph. Later found out thermal runaway protection kicked in, and I thanked the gods for having decided to install a custom firmware to enable that protection.
I have an anycubic i3 mega, recently upgraded with an E3D v6. To make that upgrade, I had to splice new connectors on both the thermistor and the cartridge, as the ones they came with weren't going to work.
Ever since upgrading I started experiencing some weird Z-wobble, but I am coming to the conclusion that it may actually be a slight consistent underextrusion. The final layers of the parts I had been printing, are all severely underextruded, going as far as delaminating. I have attached both a picture of the temperature reading, and one of the failed parts. You should also see the underextrusion I was talking about in the first layers, and the major underextrusion in the final layers.
Now, I don't have a lot of experience with this kind of issue but I think the temperature was jumping around too quickly to actually be a good reading. Sadly I was only able to take the final part of the graph before the printer shut down.
I have taken some steps to try to avoid this from happening again

I have reseated the thermistor and the cartridge
I have reseated the connectors for the thermistor and the cartridge
I have re-zip tied and changed the orientation of the wires and hotend to something that seemed better.

Before this all went down, I had ordered a titan extruder to try to mitigate the underextrusion, as I read online (I think it was from E3D official sources) that the internal pressure of the v6 may be higher than the standard hotend and therefore I may have needed a geared extruder.
Do you have any advice for me? And if you could also help me figure out if the first layers actually show underextrusion or Z-wobble, thanks for making it this far.

I should mention that this had happened to me already but without triggering the protection, the part did heavily underextrude but it was just a test part while trying to find out what was going on with the "Z-wobble." It doesn't seem to consistently happen every time I start a print, but I figure that long prints would certainly make it more likely to happen.

how tight did you make the thermosensor clamp?

Just as recommended, tightened until grub screw touched, and then an additional 1/8 of a turn. Also did tug tests.
https://e3d-online.dozuki.com/Guide/V6+Assembly/6?lang=en

When you installed the new firmware, did you PID tune your hotend? Also, is the part cooling fan blowing on the nozzle block?

@0scar No, I did that after installing the hotend. The firmware was installed much earlier. The part cooling fan doesn't seem to be blowing on the nozzle, as I have done some prints at 100% fan speed without issue.

If you had 100 % fan speed always on, then the hotend can keep the temperature, it is a problem if it schedules on/off constantly.

@0scar I have it in Cura at a standard speed of 60%, with a maximum speed of 100%. However the layer times were definitely too long to go that high, especially because I had multiple parts in a single job.

These drops are very fast, this is either forced cooling or sensor failing/seating.

Okay, thanks for the insight. i did assume something like that, I reseated it and for now it's been going okay. You'll hear back from me pretty soon if it's not fixed.
In regards to that weird Z-wobble that I'm seeing, can you recognize any particular signs that can point me in the right direction? I'm thinking I'm actually underextruding as I had to set my flow multiplier to 105%, while before the new hotend I had it at 95%.

Periodic temperature irregularities, such as cycling between a higher temperature and lower temperature slowly enough that it spends at least a layer or two at a different temperature than other layers has a tendency to be mistaken for z wobble.  You can actually intentionally modulate print temperature (at least of PLA) every few layers to great a sort of banding or 'wood grain' effect.  Higher temperature, for whatever reason, results in thicker perimeters and cooler temperatures thinner ones.  This is when always staying above the normal PLA print temperature though.  The temperatures in the graph would certainly cause serious under extrusion during the times it was under temperature.
Understand though, it is likely that temperature has been behind the underextrusion, rather than it being a problem in of itself.
It isn't possible for the temperature to jump around too quickly to get a good reading.  The temperature changes relatively slowly, simply due to the thermal mass of the heat block.  It takes a little bit for the extruder to come up to temperature, right?  When warming up from room temperature, watch how fast the temperature changes. That's the fastest the temperature can change, because that is when the heater cartridge is on at full blast.  And even then, it isn't particularly quick.
It also does not appear to be a problem with the thermistor.  If there was a poor or failing connection (like a wire that was almost broken), this would cause added resistance to the thermistor reading, and thermistors usually lose resistance as they heat up.  So extra resistance throwing off the reading would make the printer believe that the hotend was cooler than it actually was, and you would wind up printing at a too high of a temperature.  This would cause a number of problems, but your interlayer adhesion would be excellent.  Delimitation would not be one of the issues, nor would underextrusion.
Thermal runaway protection is kind of a misnomer, because it is really 'something about the temperature of something isn't behaving like it should' protection.  Basically all it is is a hard coded temperature and time window.  If it has turned on the heater, there is a hard coded number of degrees that the thermistor must increase by within a certain time window, usually 30 seconds to a couple of minutes.  If it doesn't, something is wrong.  Or, if it drops out of the intended temperature by another hard coded number of degrees for a certain amount of time, then again the thermal runaway protection will be triggered.
In cases where the connection to the thermistor is failing, this will prevent the hotend from being heated without any limit (poor thermistor connection means the temperature the printer reads is always much much lower than what it really is, so the printer keeps trying to heat the hotend up hotter).
But thermal runaway protection will also get triggered for much more benign problems, like a failing connection to the heater cartridge.  If the thermistor is working fine, but the cartridge is not working correctly and either only heats intermittently, or has a poor connection and can't get enough current through it, this will also result in the temperature not going up as expected, thus triggering the thermal runaway protection.
Based on your symptoms, the thermistor reading looks to be quite accurate.  What you describe is exactly what I'd expect would happen for a print where the temperature of the hotend really did vary exactly as shown in your graph.
What can often happen is one of the leads (especially close to the cartridge but really, it could happen anywhere along the length of the two leads) will have broken from repeated wire strain (if you have disassembled your hot end at all or otherwise disturbed the heater wires in anyway, this is more than enough to cause a lot of metal fatigue), but the insulation around the broken wire will hold it together such that wire will still be making contact with itself.  But it will be a more resistive connection, and will cycle between an acceptable and poor connection as the print head position moves.
Long story short, you get a temperature graph that looks just like that, because the heater cartridge is periodically either developing a poor connection, or losing its connection entirely, only to regain it again as things move just the right way again.
I would double check all your connections to the cartridge, checking the actual resistance and not just using a continuity tester.  If those seem ok, then you will probably just need to buy a replacement cartridge.  I like to keep a few of them on hand since they have a tendency for their wires to break just from a little bit of normal manhandling.


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What is the melting temperature of a 3D printed part?
Here is the context
I've got an old car for which I have a small plastic piece who is broken. As it's an old car and a very specific piece, I can't find it anymore. So I was thinking about 3D printing it.
My problem is this piece is on the carburetor, so close to the engine. This means, it can heat a lot, close to 90-100 °C.
My question
Do the pieces created with the common 3D printing techniques melt at 100 °C? If yes, what kind of other 3D printing technique can I use?
Here is the piece I want to recreate (sorry for the bad quality), the scale is in cm.

That depends on the used material for the print. You might be more interested in the glass temperature though, these range from 50 to 160 °C from PLA to PEKK, note that the higher glass temperature plastics are hard to print on home 3D printers (requires bed and enclosure heating over 150 °C).

Nylon and ABS will work fine, the temperature is not so high as you think. Also, consider using a printing service which can print for you even metals... if you want.

The number you're looking for is the glass transition temperature (the lowest temperature at which the material can flow or warp), not the melting point.  This depends on what material you're using; approximate temperatures for common printable materials are:

PLA: 60˚C
PETG, high-temperature PLA: 95 ˚C
ABS: 105˚C
Nylon: typically 70˚C or above ("Nylon" is a large family of similar polymers)
Polycarbonate: 145˚C

Any plastic under your hood is probably either nylon (for its durability, impact resistance, and chemical resistance) or ABS (for its strength and heat resistance).  These are both difficult materials to print: ABS emits toxic fumes while printing, and tends to warp if you're not using a heated enclosure, while nylon readily absorbs water from the air, causing the filament to bubble as it's printed.  Further, many printers can't handle the high temperatures needed to work with these materials.
If you're going to print this yourself, I recommend using PETG and inspecting the part after a few days of use to see if it's warping.  PETG is reasonably easy to print and comes close to your target heat resistance.
If you're going to get someone else to print it, I recommend using ABS.  It's probably what the original part was made of, and anyone willing to print ABS for you will have the heated enclosure and ventilation system to deal with printing it.
I'd avoid polycarbonate unless you know the original part was made of it.  Although PC is strong and heat resistant, it's also somewhat brittle and vulnerable to scratching.
High-temperature PLA is also brittle, and requires a heat-treating step that will change the dimensions of the part.  It will likely take several tries to get something that comes out the right size, and even then, you risk having the part break when your car hits a bump.

Thanks, it's exectly what I was looking for. The original part is brittle (that's why it's broken), so it was maybe made of polycarbonate. Is it hard to print? Otherwise I'll do it in PETG. It's the cooling water who is close to 100 °C, so it should be less for the part

PC is very hard to print with and very abrasive.

@Phantom, polycarbonate requires high temperatures to print, beyond the capabilities of most consumer-level printers.

@Phantom Those car parts are often made of ABS (because not even the surface of the engine gets to 100°C, since there is water cooling it) or nylon, maybe nylon with glass fibers just like computer fans

Depending on the exact mechanical load and material used to print, you might get away with 100 °C.
Next to the melting temperature required to print the material (which will always be substantially higher than the maximum useable temperature!), you probably also want to have a look at the glass temperature of your specific material. Around that temperature your material becomes soft (rubber like) and can deform permanently when cooling down again. Chances exist that under a considerable mechanical load, the part will deform at even lower temperatures.
Maybe it would help to post a picture or describe the exact component you're trying to replicate. It might help in finding an alternative solution. (E.g. carving out of say PEEK to say anything.)

I recommend this video by CNC Kitchen, as it shows an interesting, accurate and detailed, side-by-side comparison of heat deformation of custom 3D printed test samples, printed from various materials:

PLA
PETG
ABS
HT-PLA
3dkTOP

He even CNCs a custom, yet simple, test rig in order to carry out the test.
Well worth a watch.

The results for the various filaments can be seen in this graph, taken from the video:

In summary, the annealed 3dkTOP filaments perform very well, without failure, and annealing PLA helps considerably (although some shrinkage is incurred)

This answer is voted by the community as a link only answer, link only answers are not allowed and are useless when the referred content dies. From the help section under deletion of answers I quote a reason for answer to be deleted: "barely more than a link to an external site”

If you care to expand upon your answer and write down some salient points from the video, then that would be useful and would get your answer undeleted.

or state why you recommend it...

I only use an ingeo 850 or 870 PLA that have different melting temp and more resistant the normal PLA. It's a lot easier to print with a normal desktop consumer printer then ABS or NYLON
Doesn't have the same characteristics as a nylon filament but it can be used inside a car, I have used to print some parts for my car.
https://www.natureworksllc.com/~/media/Files/NatureWorks/Technical-Documents/Technical-Data-Sheets/TechnicalDataSheet_3D870_monofilament_pdf.pdf?la=en

(sorry but it's in spanish but a termal test)
Another option is to make a mold with the 3d printer and use a high temp resin

You might want to check out printing with nylon. It's not typical of most 3D printers but you could always have it printed with a printing service, since it's a one off part. They can withstand a good amount of heat.

Do you have the melting point of nylon? It might be an idea to [edit] and add that bit of info...

Have the part commercially printed in metal.
I haven't used a commercial 3D print service so I can't recommend one, but I know there are many out there and the prices are reasonable. For example, I found that if their terms of service did not prohibit weapons, I could have had Shapeways print magazines for my FX air rifle in gold plated, hand polished stainless steel for less than FX charges for one machined out of aluminum.
So, print the part yourself in whatever material you have available to ensure that it fits and operates correctly. Then upload the file to a company that can print it in metal.
A possible DIY alternative, depending on the shape and size of the part, would be lost PLA casting. Hobbyists usually do this with aluminum.

Do the pieces created with the common 3D printing techniques melt at 100 °C?

The problem here is the "common 3d printing techniques". If you mean END USER DESKTOP - yes. PLA, ABS etc. have all glass temperatures (where they get soft) around this number. Melting is not something you care about - because it will deform WAY earlier. Melting is when it gets liquid, you care when it looses stability.
If you talk NOT about desktop, then no - common 3d printing techniques THEN include laser syntering nylon as well as FDM printing materials like PEEK which have melting temperatures WAY higher. KEEP gets soft around 143 and melts around 343 degree, though some have sueful operating temperaratures up to 250 celsius. "Common" is a very vague definition in the higher end area because there are quite a number of main market different techniques that you basically never see in the consumer market due to price.
The problem is that those are expensive, so desktop users do not use them. They also require high temperature chambers AND special 3d printers. Nothing you can not do - Slice Engineering sells a hotend that can go up to 450 degree or so - but they are NOT common on the desktop side as they are (also) quite expensive. Heck, the are just now putting that into the Marlin firmware (you also need to measure this, and the thermistor table for their sensor was just added as #67 to marlin). I am reworking a printer with this technique (just for fun) and - the extruder / hotend combo costs around the same as the whole printer originally did.

If yes, what kind of other 3D printing technique can I use?

Basically any that works with the temperature band, which does include FDM printing. That said:

I think you really are wrong with the temperatures. Close to the engine may be higher than 100 degree, me thinks. If I am wrong (and that really depends on how close to the engine block it is), this may be ABS. ABS or PLA variants are available with glass transition temperatures above 130 degree, so this COULD work, depending on the exact material you use.
I would basically print it in anything common (pla) to see that it fits (NOT use it), then have a 3d printing service make it out of some engineering material. They will also be able to choose the best material for you. This is for higher temperature and possibly not FRM process. They will know what to use.

Another problem is - we do not kknow anything about this part. is it under pressure? I ask for a number of reasons.

3d printing may be less stable in certain directions than in others. Generally LESS stable than parts that are injection molded, unless you use some special techniques not common in consumer laser printers (i.e. plasma fusing the layers, which Essentium does, or laser syntering where there are not real layers to see). You MAY be able to work around it, by making the part larger / heavier (the walls), but this is something to consider. You can get more information on Essentium's work i.e. here: https://3dprinting.com/news/essentiums-fusebox-plasma-3d-printing/ - they bascially can reheat the plastic to fuse way better. They also print with speeds up to 1m/second, extremely impressive to see.
Standard 3d printing may be leaking, particularly under pressure. This is a problem as above (the layers not being perfectly bonded). Again, more layering may solve this, as would a larger nozzle.

Although metal casting has been briefly mentioned, another approach to your problem would be to create a silicone mold from your print and cast the part using epoxy or polyurethane, both of which have the desired strength and heat properties.
Here is an example of this technique

I would take a different approach.  I would use brass or copper, machine it on a lathe to get the two diameters (you need to start with a thick piece so you are left with reasonable wall thicknesses), or, alternatively, use spin-forming to enlarge it to the diameter needed (works with copper, and you can use normal thin-walled pipe because you are only re-forming it, not cutting anything away), drill a hole in the side, thread it, and use a die to create a thread on the insertion pipe.  then I'd screw it it, and finally solder it into place with a high-strength (lead-free) solder.  The threading helps reduce stress on the solder joint; I can imagine it would crack a straight solder-only join without much usage at all. That right-angle joint of small diameter is going to be the weak point.   It is the most likely place to have it snap, or start delaminating.  That part was probably injection-molded as a single piece, reducing the effects of stress and eliminating any consideration of delaminating.
Note also that some of these parts have been computer-designed to precise dimensions, and a slight change in the ID of the side-pipe, or even its OD, might make a drastic change in its behavior.
If your only tool is a hammer, all your problems look like nails.

Nylon is probably your best bet.
It is resistant to some chemicals as well.
Figure on printing it at around 250 °C.
It might do the job.

What does the link add to the answer?

It might be a link to a useful contrast of various 3d printer filaments.

Please introduce the link if it is relevant for the question. As it is now it is just a loose link.

The problem with your link in the answer is that you haven't summarised it. Should the link die then that part of the answer becomes redundant. I've looked at the link and whilst interesting, there is an awful lot to summarise, and would be arduous to summarise well. I guess that you could summarise by quoting the properties section for each filament... that would be very useful.

Um.  Just for your entertainment, I will pull the link.


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Ender 5 Printing Issues
I'm brand new to 3D printing. Just got me an Ender 5 Pro. After messing around for the last couple of days with bed leveling, I'm finally able to get consistent first level all thought I have to increase filament speed to 120 otherwise there are too many gaps in the base. Now I'm trying to work out issues printing this Calibration cube.
My corners are being rounded too much and therefore size of cube differs. 20.02-20.08 mm when checking middle or when including corners goes to 20.50.
When I printed a full-sized model of an owl, it looks like it has stitching on the back. And random bumps all over.

The bumps on the owl could also be your seam if it’s not overextrusion. I used to have that problem on a ton of my prints until I set the seam to sharpest corner or user defined. You can go to the Teaching Tech website to get some tips on how to fix some common problems or calibrate your printer. Good luck!


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What's so special about cleaning filament?
What is different about cleaning filament to make it effective? What is it made out of? How does it work?

You may discover that "cleaning filament" is also described as nylon filament. Nylon requires higher temperatures than most commonly used filaments. As you raise the hot end to the required temperature to melt the nylon (typically 250°C, all of the other debris has either carbonized or melted.
The hot end is allowed to cool (30-50°C) at which point the nylon filament is pulled out in the reverse direction. Some 'net references suggest a hard pull, but I disagree with violent mechanical forces being applied to delicate mechanical devices. Perhaps that's why my cleaning process takes two to four attempts. Some net references also suggest to start the nozzle heating after reaching the cooling point and to begin applying force upward during the re-heating.
My Sigma 16 uses the above method and also suggests a "strong pull" which is a translation from "sharp yank," in my opinion.
This will collect the debris from the nozzle and heat break and may completely clean the filament path.
I use "natural" clear nylon for cleaning and perform the sequence two to three times, until the heated portion of the nylon no longer has contamination visible.
Even nylon filament that is not dry enough for printing works for cleaning. The moisture bubbles turn the filament into flimsy punctured nylon thread, but it causes no problem with the cleaning process.
FilamentOne website references most of what I've posted.

The above image resembles my experience, although the severely "dirty" image is much more excessive than my cleanings. The worst is to have PVA support material that has been "cooked" at ABS temperatures or higher for long periods. An almost guaranteed nozzle clog is the result of those conditions.

Excellent answer!

So: heat, cool, start to heat again, apply pressure as the temp rises?

That's black filament residue, not carbonized filament afaict. Looks like when I accidentally loaded the wrong color and immediately pulled it out after loading.


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Shell detaches from the rest of the part
I'm printing with a Prusa MK3, with the following settings:

3 perimeters
50 % infill
infill overlap: 50 %

The filament is Polyalchemy emerald green (PLA). Nozzle temperature: 210 °C.
On a simple part (it's a keychain), the shell detaches if I apply a bit of force on a zone of the part that is "fragile". See picture. You might not be able to see it, but only the 2 external perimeters detach from the rest of the part. I used to print this part on another printer, and I never observed this problem.
Any idea on how to solve this problem? It seems the 3 external perimeters didn't fuse properly.

What is the printing speed? You are probably printing too fast. I've seen this happening a lot with PETG.

Not particularly high, 45 mm/s for the internal perimeters, 25 for the external ones. Infill 80.

Nope, it's not the speed: I reduced by 50% the speeds above and got the same results, the part is brittle at the same place.

Belts tight? Under extruding?

What slicer? Any weird setting?

The overlap between infill and perimeters may be too low. Or there is underextrusion. I would try 3% higher extrusion rate.

210 is quite hot for PLA, you might try to tone it down to 200 or such. How many top layers do you use? I use 4 to 6 on a mere 9% infill and get quite sturdy parts (with 2-3 shells).

Did you calibrate your e-steps? what are your nozzle size and line/wall width settings?

I think the problem is underextrusion. I normally use Slic3r by Prusa. I tried the same print today, sliced with Cura: same fragility of the piece. I then tried with ABS, sliced with Slic3r: no problem. I then tried again with the green PLA from polyalchemy, with 1.1 extrusion factor: still failing. At 1.3 extrusion factor, the part is as solid as I would expect (I should also have tried with another PLA for a proper control...). I think I just need to dial in the extrusion for this filament. The sweet spot is between 1.1 and 1.3 (which seems a bit high, but ok).

I ultimately concluded that the material isn't great. I printed this part with multiple other PLAs and never observed any problem. The Polyalchemy PLA looks great, but for any part that has some sort of mechanical constraint, it behaves poorly.

I am looking at your picture, and I realize that it is not only that the perimeter is detaching from the infill, but also that the perimeter is breaking.
Once the perimeter breaks, the weaker connection with the infill will surely break, too.
You could try:

Using more than two perimeter layers.  Go big. Try five.
Add a fillet where the ring attaches so that the force is not focused on a point.
Choose an infill percentage and pattern that maximizes the contact between the perimeter and the body.
Change the angle on the bed at which the keychain is printed so that the infill maximally connects with the breaking point.  That might make the ring be 45 degrees off the X and Y axes.

If the perimeter breaks, it's likely at a seam that didn't fully bond due to a retraction problem just before the wall was started, where the start of the wall was underextruded or missing entirely. Note that slicer settings usually prefer making the seam at the sharpest concave corner, which matches where the break in the picture was.

@r.. then may I assume that you would recommend turning on random seams, if the slicer supports it?  Perhaps also changing the retraction settings?

No, diagnosing and fixing the retraction settings or whatever it is causing the weak seam. Random seams just come out really ugly and aren't even reproducible, which is bad for getting parts you can test and improve.


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Fixing Z-Hop Stringing
I'm printing a model on my Ender 3 in Mika3D Silk PLA, which (just for reference, this is not atypical) has a stated temperature of 200 °C to 235 °C. I have used this filament before and found it works best for me around 200 °C, but was not the case with this print, and I'm wondering what else I can do to fix this issue.
I have retractions enabled, have lowered the printing temperature to 180 °C and decreased the feed rate significantly, to around 75 %. Both of these adjustments happened gradually, making sure there was no change in stringing between adjustments.
I do have rafts and Z hops enabled in Cura, as previous prints of this model were knocked off the base even after leveling the bed properly, and almost every time a "hop" is performed, some stringing occurs. Is there something I can do in my settings, etc, to fix this issue?
Here is an image of the problem.

Edit: did some extra research and increased my print speed and switched to a better testing model - same issue.

Welcome to 3dPrinting.SE!

This is basically a stringing question, these have been asked and answered before, e.g. this answer. Good to see you tried several things like reducing temperature, you should explore the retraction length and retraction speed, increase travel speed and check for possible clogging by cleaning the nozzle.

Enable “wipe while retracting” will help.

@0scar: While it is a stringing question, the behavior of stringing with z-hop (and a constraint to leave z-hop enabled) differs quite a bit.

Stringing may depend on sub-optimal retraction settings: when retraction is fast and high enough, the string may be cut and disappear.
You may want to at least try to optimise retraction, at least to exclude that parameter.
There is a tool designed to properly tune retraction:
http://retractioncalibration.com/
What it does is print a tower with multiple retractions with increasing retraction distance around the perimeter. Along the Z axis the retraction speed is increased.
This tool does not include Z-hopping so stringing may be less visible, but at least you can easily visualise the optimal retraction settings. At that point if the optimal settings are much different from what you had, you may want to try your model again to see if it improved.

Cool calibration tower, not seen this before! Thanks for sharing!

It's because the nozzle has nowhere to wipe itself, like when you don't use Z hop the nozzle wipes itself off in the inside of the print. When you have Z hop enabled the nozzle has nowhere to wipe the string off, which leaves a string when it goes over to the next print. This happens to me all the time.

What improved the stringing issue in my case was increase the amount of retraction on top of the temperature reduction.
After each change, I printed one of these parts (see image below), designed specifically for testing stringing.

Can you elaborate on the amount of increase?

Check http://retractioncalibration.com/


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Help needed to design 3D printer part
I am attempting to build a 3D printer using the Bear Upgrade for guidance.
However, I want to modify some of the parts. I am basing the modified parts on the original designs.
I would like to understand the reason behind some design details presented on the original designs so that, if necessary, introduce them into the new designs.

Item 1) The holes are not round. Why???
Item 2 ) There are some little squares inside the piece which i don't know if they are there for some structural reason
Please use this link to the piece depicted above.
Here is a drawing of the full assembly, showing that this piece is the y axes linear rods holder:

Welcome to 3dPrinting.SE!

Item 1) The holes are not round. Why???

Two things about this. First, the print is upside down. The holes are not round to accommodate the fact you cannot print a round hole unsupported. If you try to print the circle unsupported, when you get to the top portion, it will sag until the print catches up to it. By that time, the circle is flat at the top and you won't be able to fit whatever you were trying to fit into it (without some post processing). Printing the V-ish looking part at the top will ensure you'll be able fit things through it you meant to fit through (sorry if that's redundant). If you'd like to know more, take a look at the following Maker's Muse video:

Item 2 ) There are some little squares inside the piece which i don't know if they are there for some structural reason

To be very honest with you, I don't know why the little squares are there either, however, I believe you can answer this part for yourself.
I think the answer lies in the part, meaning, if you can manipulate the 3d design in whatever you're using to design it, you can look into the part and see what's going on with it. It appears there are dashed lines in the center parts, which would make me believe these are hidden lines. There is a feature there which is inside of the part which you cannot see otherwise. By turning it, you should be able to decipher what these features are for and therefore should be able to discern what the small squares a for as well. If, after you've looked the part over completely you cannot discern a purpose for the squares, don't design them into your part. It may just be they are an artifact of the design itself and doesn't provide anything worth repeating in your own design. Bottom line, don't get hung up on the minute details which in the end don't mean a thing.

I'm not convinced about the hole shape.  It's easy to have the slicing software put supports inside the hole so the top is properlly shaped.  THese look a lot more like they're designed for a non-rotating, "keyed" item to be inserted.

Great video, good to link it related to the design questions of the OP (has been a while that I saw it), but the flat spot in the hole is not related to printing orientation, this piece can be printed with the holes down to the build plate.

@CarlWitthoft both probably? a Teardrop shape can be used to make parts "self clamping" to some degree.

Teardrop shape
ere is a feature there which is inside of the part which you cannot see otherwise. By turning it, you should be able to decipher what these features are for and therefore should be able to

Welcome to the stack, but able to do.... what? Your answer is breaking off. You can [edit] it and add to it.


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17-4 PH Tensile Test
When I do a tensile test on 17-4 PH stainless steel, the stress-strain curve is very strange, two sections of Young’s modulus appeared. What is going on? The sample is made by SLM.

According to our materials experts, you should always be careful interpreting the start of the force-displacement diagram. It is possible that the test needs to "set" itself, important issues are:

the clamping of the test articles in the test bench vices
alignment of the test article in the test bench
size of the test articles (the load suggests small test articles/small diameter)
how is displacement measured (displacement/elongation sensors "slip" easily depending on the expertise of the operator)
artifacts in the test article?

Instead of proceeding the test till rupture (prior to the in-elastic/plastic region), it would have been beneficial if the test had been stopped at about 8 kN and relaxed to 0 kN to commence a new test.

From my own experience with creep test articles we see similar issues and apply a displacement offset so that the "second section" (using your words) is extrapolated to zero load. Usually this is just a few hundredths or tenths of a mm. In this case you could shift the whole diagram 0.3 mm to the right by applying a similar offset of about -0.3 mm.


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XYZ DaVinci 3D Printer constantly jamming
I have an XYZ DaVinci Mini w which keeps jamming. It does not give a Jam Error. I disassembled the extruder 1 time and found a short piece of PLA stuck in it however that did not fix anything. I've also tried using the Load Filament function repeatedly to try to get the filament out but it does not work. However, after disassembling the extruder, instead of just not printing it makes a loud repeated clicking sound.
Any Ideas?

The clicking sound typically means the drive gears are slipping on the filament because there is a jam in the head/nozzle.
First thing to do is clear the nozzle. You can use a small drill bit to clear the chamber, but if the extrusion hole (at the tip) is clogged, you'll need to get a set of fine wires designed for extruder clearing.  Then heat the head above melting point and slip the wire in (if possible).
In general, I find it easier and faster to replace clogged nozzles.  They're cheap, and more often than not clearing the exit hole enlarges the diameter (bad thing).


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Monoprice select mini V2 displaying '999' degrees for build plate temp
I have a monoprice select mini v2, and it has worked well up until now. It currently displays 999 degrees for the build plate temperature. This is a glitch, and I don't know how to fix it. Since it thinks the temperature is so high, it thinks that the build plate does not need to be heated. Because of this, many of my prints turn out warped. Is there a way to fix this?

You get this temperature reading when there is broken wire. Not owning this printer type, can't you switch out the bed thermistor for a new one? Or alternatively check if a connection is loose.

authors: Едуард Ярандайкин


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Extruder doing the shimmy, How can I fix?
Printer: Monoprice Maker Select V2 3D Printer
Problem: Extruder not working
History: My extruder was clogged and I didn't realize it at first and I opened the extruder and pulled out the stuck piece but later I realized it still was not working. When I put pressure on it the motor rotates and the filament comes out but does not work by it self.
Try 1: Thought something was wrong with the gears so I reseated them, Didn't work.
Try 2: Thought the extruder motor broke, so I replace the NEMA 17 motor, Didn't work.
Try 3: Plugged the motor into the x-axis plug the motor works as shown here -
https://photos.app.goo.gl/kY4okR4oqkYSyzhN8
This is how the motor behaves when pluged into the [original] extruder plug-
https://photos.app.goo.gl/QPo7RNeB6AFi6KsM6
Any help is appreciated, Thank you :)

Welcome to 3D Printing.SE! Did you try a different cable on extruder replacing the current one?

Have you looked into this question?

@0scar Thank you for your reply, I checked the cable with my multimeter all the wires are working as intended. My only thinking is the the board some how is damaged. Should I order a new board?

I also tried increasing the voltage too the nema motor as suggested in the other thread that also didnt fix the issue

My second guess was also a fried board...

It was the stepper driver, Replacing the motherboard fixed the issue.

Many thanks for answering your own question! Glad to see you got it fixed, happy printing!


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CR10S Pro Pausing the print at a certain layer height
Im printing on a CR10S Pro and I can't find a way to pause the print at a certain height, to insert magnets into my print. Is there a way I can do this?

Welcome to 3dPrinting.SE!

Don't be offended, but this question may be closed by the community for being a duplicate question.

I have tried all of that and it didn't work.

Have you tried inserting an M600 command in your slicer post-processing? This is the command for a filament change for Marlin firmware, which the 10S Pro should be using.

@cmm You're not wrong. I figured I'd ask for a clarification before writing an answer.

Actually, now that I am trying to write the answer, I've forgotten how I did this exactly. I'll have to wait until I get home to look at the gcode file that incorporates this.

You tried everything? G4 is supported by your printer, that works. The downside is that it specifies a fixed time, you need to get it done (filament change) in time, but it does work.

Does this answer your question? How to pause a print to insert something in a cavity using Ultimaker Cura?


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Ender 3 cracking magnetic bed
My first magnetic bed mat for my Ender 3 Pro is cracking underneath. On the top side there is a bubble in the middle which prevents any viable print. The layers are probably separating.
I am new to printing but have read many articles on hiccups to expect, fixes etc. I do understand these magnetic mats can break down. They're pretty cheap on Amazon (something like \$12 for a 2-pack). Not a huge deal. I've printed only about 1100g worth of filament over 30 prints. Despite their cheap price I don't feel I got a proper amount of mileage out of the mat.
I keep my bed at 60 °C and 215 °C for the filament. I'm pretty sure 60 °C is below the maximum temperature for this kind of bed. I am struggling to find articles on this issue.
What can I do to prolong the life of these mats? I have removed the mat (with its print) while the bed was still hot to remove items just as much as removing cold items. Am I supposed to wait until it's cold? The cracks I only assume are from flexing the mat. I'm not trying to fold it here. I do pull on the item as I'm curving the mat to break it free. I can't explain the bubble.
The bed deteriorated after my first large print which took 27 hours. Prior, longest print I had was about 5 hours, most prints 1-1.5 hours. Is this a factor?

My personal technique for removing prints (particularly larger prints) is not to flex the mat at all. Instead, I wait until it's cool and then work the spatula under an edge and move it under the model to basically peel it from the mat.
Smaller prints usually pop right off if I start with this technique from one end.
Surface area on the bed (for a single part) is most important to how much work is involved. For example, a raft or brim will greatly increase the surface area.  The spatula is long enough that usually I can reach everywhere under the model so eventually it will pop free. I might have to work around the model a bit before it reaches this point.

I had quite a few Ender 3's with magnetic beds and I did start to notice the cracks on the underside with use. To stop the cracks from appearing so soon you should avoid excessive bending of the mat. Any time where you are bending the mat near 90°s or so is when you will start to cause those stress forces that cause the crackling you see.
However, I would like to point out that the bed is still quite usable and should not need to be replaced until it no longer adheres to the build plate firmly. I would also point out that most Ender 3's that I've dealt with needed to be upgraded to glass beds for superior flatness and consistent bed adhesion. I recommend upgrading if you do decide to spend money on ned beds.


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Cura 4.4 missing object parts
I have this image in STL

But it seems cura skipped the lower panel entirely when slicing the STL.

The base is thick, as you can see here, but it is still missing in Preview, and Cura seems to ignore the base.

I have tried to decrease to 0.1mm for width or initial layer, but cura still ignored the base panel.
I also found this odd behaviour in a number of my models.. such as this:

or this

Notice those missing parts? It is like some parts are floating in the air.
Can someone help me out here? What kind of setting I have to modify?

often, such models have inverted faces in these areas. look at this and this answer

Using the preview feature as you have is a good method to determine that the original model is flawed. It's not unusual to discover detailed models have reversed normals or non-contiguous surfaces, which will not print.
In a simple example, consider a cube for which five of the six faces are properly described by the design software. This would result in all eight vertices being present, allowing the software to present the "missing" face, but the slicer is unable to create this aspect. The cube is no longer solid and is presented as seven zero-thickness panels, which can't be printed.
It is necessary to repair the broken models, by closing gaps and reverting/recalculating normals, but that requires skill in other software.
Some slicers will attempt to repair damaged models, but some are so severe, the results you've experienced are the result.
If you want a confirmation of a failed model, load it into free Meshmixer, run Analysis/Inspector and expect a "pincushion" of highlighted failures.

among the softwares that can do so are: Blender (by just doing a recalculate normals) and Meshmixer (which has an automation)


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Saving BL Touch settings
I have an Ender 3 Pro with a BL Touch.
In my G-code should I add an M500 after the G29, to save the results to the EEPROM? I know storage size is an issue, so does storing these results cause an issue?
I believe the saved results can be activated before the next print using: M420 S1
If I do, does that mean I just auto home (G28) but don’t need to run a G29 until I think the bed has lost its level?
I was trying to clarify this after reading:
BL Touch Probing Fails Intermittently

From this source you can read:

After a G29 the leveling data is only stored in RAM. You have to use M500 to save the bed leveling data to EEPROM, otherwise the data will be lost when you restart (or reconnect) the printer. Use M502 to reset the bed leveling data (and other settings to defaults). Use M501 to reload your last-saved bed leveling from EEPROM. This is done automatically on reboot.

The source also answers the use of M420 S1:

After a G29 bed leveling is automatically enabled, but in all other situations you must use M420 S1 to enable bed leveling. It is essential to include the command M420 S1 in the “Start G-code” in your slicer settings. If you have no bed leveling, or if there is no leveling data, then this command is simply ignored.

So, if you're not using a G29 in your start code you must use the G-code  M420 S1 to enable the stored mesh from memory.

Thank you. I had read the Marlin site but was still not clear on the relationship between G28 and G29, because I did read that G28 was needed but that it disabled ABL.
I assume that as long as I had saved the settings with M500, the use of M420 S1 turns it on with the latest established settings.

it's usually god to not store the items and relevel before each print unless you have time concerns.