text:
Low hanging fruit improvements to FDM printers that are patented
What are some relatively simple improvements to FDM 3D printers that cannot be sold however because they are under patent?
I know a heated build chamber is one such thing: According to the RepRap Wiki Heated_Build_Chamber:

The disclosure on how to fabricate a heated build chamber might also be illegal as it is protected by patent.

So I wonder if there are similar "simple" FDM printer upgrades for which it currently would be forbidden to sell (or even promote?) parts due to patent infringement.
This is exactly the question I am interested in. This is not about a specific printer. A heated build chamber is a simple upgrade that would benefit pretty much any FDM printer. I am interested in other relatively simple upgrades which you won't find on most commercial 3D printers despite their simplicity for the reason that the feature is patented.
What other simple improvements are there, that are protected by patents?

The edit still does not make it answerable. From [help] center: Your questions should be reasonably scoped. If you can imagine an entire book that answers your question, you’re asking too much. There could be a lot of patents out there limiting selling. What would be gained when you know the list if you don't know what to upgrade? It would be better to state your problem so that people can recommend viable upgrades for your problem, rather then speculate on what you could have used instead.

"The disclosure on how to fabricate a heated build chamber might also be illegal as it is protected by patent" is nonsense. The patent is the disclosure of how to do it.

@R but I guess if you explain the process on your website and by that drive traffic to your site you’re also making use of the patented invention, at least that’s how I understood that phrase..

As far as I know, "heated build chamber" in general is not patented. What is patented it a specific implementation of it, where the motors are outside the build chamber and not exposed to the heat.

The disclosure on how to fabricate a heated build chamber might also be illegal as it is protected by patent.
That's the exact opposite of how patents work.

Porosity control
Seam hiding
Dissolvable supports

Porosity Control - The ability of a 3d printer to produce a variable infill rate (e.g. 20%) is covered by a Stratasys utility patent.
Seam Hiding - The ability of a 3d printer to start printing from a different point on the perimeter such that no seam appears on the printed part, is covered by a Stratasys utility patent.
Dissolvable supports - The ability of a 3d printer to print with 2 (or more) filaments such that one of the filaments, acting as support material (or scaffolding), can be removed by sustained immersion in water, is covered by a Stratasys utility patent.
Defendant Microboards Technology, LLC d/b/a Afinia's answer to Plaintiff's complaint for patent infringement; Affirmative Defenses; Counterclaims; and Demand for Jury Trial
I could not find a URL with the original Stratasys case, but I saved a copy back when it first came out. The document seems to be behind paywalls now. You can reference it as :
CASE 0:13-cv-03228-DWF-JJG
UNITED STATES DISTRICT COURT DISTRICT OF MINNESOTA

could you link the stratasys complaint too? the answer is impossible to read without the complaint itself

Interesting... I've seen the dissolvable supports thing for a while now, with support in several slicers. I've never had problems with visible seams, either. But the porosity control sounds intersting, where a model could be more hollow towards the center, and use more infill as you approach the top layer so that top doesn't need to bridge as much.

Now we know why PVA material is so expensive... :)

Let's hope Chinese engineers show their usual lack of empathy towards patent holders.


text:
Convert a 3D NumPy array of voxels to an STL file
Given a 3D boolean array representing voxels, how can it be converted to a 3D-printer-ready file?
The end-goal I would like to achieve is to print the 3D shape that the numpy array represents (True coding for fill this voxel, False for leave it empty).
For example, the array
[
    [
        [T, T, T],
        [T, F, T],
        [T, T, T]
    ],
    [
        [T, F, T],
        [F, F, F],
        [T, F, T]
    ],
    [
        [T, T, T],
        [T, F, T],
        [T, T, T]
    ]
]

would encode a level-1 Menger sponge.

Seems like OpenSCAD would be suitable for this.

I agree with the use of OpenSCAD, but since it is difficult to program in OpenSCAD, I would use SolidPython, which is a front end for OpenSCAD with the full programming capability of Python.
In the alternative, you could use any programming language to decode your arrays and generate the OpenSCAD code for the little network of cubes (or voxels).
The final possibility is to generate an STL file directly.  I've helped someone do this, but we found the rules to be a little non-intuitive.  We used mesh tools to check out results, both by looking for error messages, and by displaying the result to see if it looked as we intended it to look.

It's also possible to generate STL files in Python using numpy-stl.

An OpenSCAD approach will be fine if you're going for a low-res minecraft style model with a smallish number of cubes. If the voxels are supposed to approximate a smooth surface at the printer's best resolution, then OpenSCAD will take days to render it out. There has got to be a better way to do this!

Try voxelfuse.
    from voxelfuse.voxel_model import VoxelModel
    from voxelfuse.mesh import Mesh
    from voxelfuse.primitives import generateMaterials

    if __name__=='__main__':
    sponge = [
        [
            [1, 1, 1],
            [1, 0, 1],
            [1, 1, 1]
        ],
        [
            [1, 0, 1],
            [0, 0, 0],
            [1, 0, 1]
        ],
        [
            [1, 1, 1],
            [1, 0, 1],
            [1, 1, 1]
        ]
    ]

    model = VoxelModel(sponge, generateMaterials(4))  #4 is aluminium.
    mesh = Mesh.fromVoxelModel(model)
    mesh.export('mesh.stl')

It's great that you posted an answer, with a code example, thereby expanding upon your comment. However, I can't help wondering whether a little explanation of the code would help significantly, i.e. a brief detail about each line (especially the last three lines). Just to save people having to go off and google VoxelModel in order to understand what is happening in the code.

@greenonline, sometimes I have little time and my answers are rushed- you are correct that this was minimal. But Python is (generally) so easy to install packages, ang Google is our friend for more details, in this case I thought maybe it would help the questioner.
I would also have offered more had I had more experience with voxelfuse - but I generally use other modules for my 3D work..

You can try mayavi.mlab:
Usage
from mayavi import mlab
import numpy as np

def draw3d_mayavi(array, path):
    mlab.contour3d(array.astype(np.int32)) # a window would pop up
    mlab.savefig(path)
    mlab.clf() # clear the scene to generate a new one

mayavi's recontruction is meant for generating 3D heatmap models of the array, so you have to put in a numeric one with 1s and 0s.
Note
There are some drawbacks:

A window will pop out, you have to clear it in your code if you want to make multiple models.

The model reconstructed is .obj and can be very large. If you look closer at the model, you'll see that on the boder the mesh gets 3 layers. I guess the program assumes there to be some gradient.

The contour3d function can set line_width, but I don't see any sense of using it for binary data.

Yet, mayavi is very quick, at least compared with voxelfuse. Maybe some post-processing is needed to solve the size problem.
Doc
This function also enables setting color and opacity, etc.
See Plotting functions - contour3d:

contour3d
mayavi.mlab.contour3d(*args, **kwargs)
Plots iso-surfaces for a 3D volume of data supplied as arguments.
Function signatures:
contour3d(scalars, ...) contour3d(x, y, z, scalars, ...)
scalars is a 3D numpy arrays giving the data on a grid.
If 4 arrays, (x, y, z, scalars) are passed, the 3 first arrays give
the position, and the last the scalar value. The x, y and z arrays are
then supposed to have been generated by numpy.mgrid, in other words,
they are 3D arrays, with positions lying on a 3D orthogonal and
regularly spaced grid with nearest neighbor in space matching nearest
neighbor in the array. The function builds a scalar field assuming the
points are regularly spaced.
Keyword arguments:

color the color of the vtk object. Overides the colormap, if any, when specified. This is specified as a triplet of float ranging from 0
to 1, eg (1, 1, 1) for white.

colormap type of colormap to use.

contours Integer/list specifying number/list of contours. Specifying a list of values will only give the requested contours
asked for.

extent [xmin, xmax, ymin, ymax, zmin, zmax] Default is the x, y, z arrays extent. Use this to change the extent of the object created.

figure Figure to populate.

line_width The width of the lines, if any used. Must be a float. Default: 2.0

name the name of the vtk object created.

opacity The overall opacity of the vtk object. Must be a float. Default: 1.0

reset_zoom Reset the zoom to accomodate the data newly added to the scene. Defaults to True.

transparent make the opacity of the actor depend on the scalar.

vmax vmax is used to scale the colormap. If None, the max of the data will be used

vmin vmin is used to scale the colormap. If None, the min of the data will be used

Example (run in ipython --gui=qt, or in the mayavi2 interactive shell, see Running mlab scripts for more info):

def test_contour3d():
    x, y, z = np.ogrid[-5:5:64j, -5:5:64j, -5:5:64j]

    scalars = x * x * 0.5 + y * y + z * z * 2.0

    obj = contour3d(scalars, contours=4, transparent=True)
    return obj ```

Welcome to 3D Printing SE and thank you for your contribution. Could you summarize the "Doc" you linked to since links can "die" over time? Also, when you get a chance, please take the [tour] to understand how the site works and how it is different than others.

source: Stack Exchange

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

authors: Гоша Манданюк

sort: votes


text:
Display locks when executing G-code for laser cutting using Marlin on RAMPS board
I'm working on a Laser cutter. I’m using the RAMPS 1.4 and Marlin software. To make the Marlin software work with a laser I’m inspired by this blog from dreammakercnc: Marlin Firmware modification for Laser Control
My plan is to use Inkscape to design and create the G-code. With Pronterface I will sent it to the laser cutter. My plan is to get the Marlin software to work like in this video:

.
After that I will order the laser cutting machine.
For now I have the following issue:
I'm using stepper motors. They are working when I connect to Pronterface. I can control the motors when I'm using Pronterface. But when I load a G-code file, that I designed with Inkscape, the program seems to freeze. Nothing happens. It's saying:

locking interface.

When I unlock it and sent a manual G-code it's not working. The program thinks its working at that moment. The picture that I designed is visualized in the G-code viewer of Pronterface.
I haven't connected any extruders, fan or bed to the RAMPS 1.4. I have connected one thermistor and one endstop. Both are working well. When I upload the Marlin software there are no problems.
My thoughts:

Is my problem that the program is waiting for the extruder to get warm?
Is there something wrong with the G-code I’am sending to the RAMPS board?

Below I will put the info from Pronterface when I connect, the G-code that I'm using and the configuration.h file from the Marlin software.
Pronterface connecting

Connecting...
start
Printer is now online.
echo: External Reset
Marlin 1.0.2+
echo: Last Updated: Jun  6 2019 22:04:53 | Author: (Bart,24-1-2019)
Compiled: Jun  6 2019
echo: Free Memory: 5248  PlannerBufferBytes: 1360
echo:Hardcoded Default Settings Loaded
echo:Steps per unit:
echo:  M92 X78.74 Y78.74 Z533.33 E836.00
echo:Maximum feedrates (mm/s):
echo:  M203 X500.00 Y500.00 Z5.00 E25.00
echo:Maximum Acceleration (mm/s2):
echo:  M201 X9000 Y9000 Z100 E10000
echo:Acceleration: S=acceleration, T=retract acceleration
echo:  M204 S3000.00 T3000.00
echo:Advanced variables: S=Min feedrate (mm/s), T=Min travel feedrate (mm/s), B=minimum segment time (ms), X=maximum XY jerk (mm/s),  Z=maximum Z jerk (mm/s),  E=maximum E jerk (mm/s)
echo:  M205 S0.00 T0.00 B20000 X20.00 Z0.40 E5.00
echo:Home offset (mm):
echo:  M206 X0.00 Y0.00 Z0.00
echo:PID settings:
echo:   M301 P22.20 I1.08 D114.00

G-code

Loading file: D:\output_0001.gcode
Loaded D:\output_0001.gcode, 27 lines
0.00mm of filament used in this print
The print goes:
- from 0.00 mm to 36.62 mm in X and is 36.62 mm wide
- from 0.00 mm to 49.24 mm in Y and is 49.24 mm deep
- from 0.00 mm to 0.00 mm in Z and is 0.00 mm high
Estimated duration: 0 layers, 0:03:09

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


text:
How to prevent stringing with 0.25 mm nozzle?
When I print with a 0.4  mm nozzle I have no problem with stringing at all but because I need a more detailed print I must use a 0.25 mm nozzle.
I use Ultimaker Cura and an Anycubic i3 Mega.
What i tried so far:

Enable/Disable Z hop
Tried different retraction distance and speed.
Tried with lower temperature
Different wall thickness

If you have any suggestion please let me know.

Welcome to 3dPrinting.SE! Have you changed the nozzle size within cura?

Yes i have changed the line width to 0.25

Nozzle width and line width are separate.

First, you should change the nozzle diameter setting, not just the line width setting, in Cura. Both are involved in determining extrusion. Line width can be less than or greater than nozzle size, but setting it much larger or smaller is not going to work well.
I suspect your main problem, though, is print speed. The area of the 0.25 mm nozzle orifice is only 39% of the area of an 0.4 mm nozzle orifice, bounding the material extrusion rate at best at 39% of what you could get with the larger nozzle (in practice it will be even lower due to complex fluid dynamics, probably much lower), but at the same linear print speed with narrower lines, you'll be extruding (or trying to extrude) 62.5% as much material per unit time. Now, if that much material can't actually make it out of the nozzle, pressure builds up between the extruder gear and the nozzle, and stringing is the result.
So, try lowering the print speed. A lot at first. If that solves the problem, gradually increase it until you find the limit. Increasing retraction and temperature may help you push it a little further. See my question and self-answer on stringing with flexible filaments, which might give you some ideas on other things to try:
Avoiding stringing with flexible filament

What worked well for me in avoiding stringing is to increase the travel move speeds significantly, disable Z-hop and to decrease printing temperature

These are definitely both good ideas. At first I was confused that z-hop might help avoid stringing, since I mistakenly believed it was caused by re-melting and dragging correctly-deposited material. But after spending a lot of time on it, I found that pretty much all of it was a matter of new material coming out of the nozzle during travel or dragging incorrectly deposited material due to previous oozing from the nozzle.


text:
Change hotend thermistor input in Marlin
I have a Marlin driven Prusa i3 clone, by accident I cut through both thermistor wires for the hotend while it was powered on. The Arduino reset and the hotend thermistor no longer work.
Since there is a spare thermistor input on the RAMPS board I was wondering if I can change the input pin assigned to the hotend thermistor in the software? I've looked around (the code and the internet) and so far have only found out how to assign the thermistor type for the spare input, not how to tell Marlin to make temp_sensor_2 be the input used for the hotend?
If anyone could help me figure out how to change the hotend thermistor input number I would be greatly appreciative!

In pins_RAMPS.h you find which pins are used for which thermistor:

//
// Temperature Sensors
//
#define TEMP_0_PIN         13   // Analog Input
#define TEMP_1_PIN         15   // Analog Input

To use the other thermistor, you would need to swap the numbers:

//
// Temperature Sensors
//
#define TEMP_0_PIN         15   // Analog Input
#define TEMP_1_PIN         13   // Analog Input

Well I am having same problem, I changed the pin no and pin 15 is working but all other pin (12, 13, 14) are not working. I am using Anycubic Trigorilla... Can I use any other pin for this?


text:
Wanhao i3 stops printing after about 40 minutes
I have a Monoprice Maker Select V2.1 (rebadged Wanhao Di3) with a microswiss all metal hot-end and machined lever and extruder plate. It had been printing very consistently for months with this set up - through 5 or 6 kg of filament - until a couple of weeks ago when it has started to under-extrude and then stop partway into a print, after about 30-40 minutes. It seems to clog and grind the filament, skipping steps. I first assumed this was heat-creep, and so disassembled the extruder, cleaned the heatsink and applied new thermal paste before reassembling, but to no luck. I also tried new fans on the cold-end but this didn't help either.
Other things I have tried:

various models - point at which the extruding stops seems based on length of time printing, not z position, suggesting to me that it is not an wires/electronics issue or an issue with the file.
various layer heights
various temperatures
dust filter
various filaments (changing reels of similar filament, different colours and brands, although all PLA)
cleaned, and subsequently replaced extruder gear to rule out wear to that
inserted washer under lever spring to add tension
clearing the nozzle (cleaning filament, atomic pulls and drill-bit)

I've now run out of ideas of what could be causing the issue and what to try. What other issues could cause the above symptoms or, if it is heat-creep, how else could I solve the issue?

I'm trying to understand you description.  Are you saying the extrusion stops, but the extruder keeps moving as if printing?

@Perry Webb - yes that's exactly it. Everything (xyz) continues to move. The plastic just stops coming out.

It sounds like it is as simple as a new nozzle to be honest. Have you tried changing it?

Have you tried new filament - new as in fresh, not just different.

The nozzle was not seated properly
Having failed to identify the problem with my current mods installed on the printer, I decided to remove everything and return the printer to factory condition to identify the problems. In particular this included replacing the all-metal hotend, and I took the opportunity to replace the insulation on the heater block too.
On removing the insulation from around my heater block, I discovered a mass of burned-on plastic that had oozed out from around the thread of the nozzle and collected under the insulation, showing that it clearly was not screwed in tight enough. After thoroughly cleaning out the heater block, replacing the insulation and reinstalling the nozzle - and ensuring it was tightly seated against the tube - I have been able to print without issue.

Time to check things that usually don't need checking.  At this point I would check the power split.
Check the power supply voltage (+12V or maybe +24V, I don't know the printer) at the controller before and after the extrusion stops or sputters.   Assure that the voltage stays the same.   If it drops you have a culprit.  While there, also check the +5V.  If the power is inconsistent,  check the connections for loose screws.  If the power is also bad at the supply,  replace it.
If the extruder starts clicking,  it could be under voltage or under temperature.  You have already checked for heat creep, and not found it.  Either supply voltage can mess with actual temperature.
You have ruled out Z-height, so many possibilities are unlikely.

Thanks for the suggestion - I'll get the multimeter and possibly scope out to investigate. Also regarding not finding heat creep - I'm not actually sure it's not heat creep, just that my solutions haven't fixed it. Your suggestions to measure things have made me think to point the IR thermometer at the cooling block while I'm at it.

An IR thermometer is a great tool.  Don't believe the absolute numbers unless you account for emmissivity, but relative numbers, now vs then, are great.

Have you checked your computers power saving settings, the USB port setting in particular, to see if your computer is turning off the USB port, the hard drive, or some other hardware vital to printing?

I'm printing standalone from an sd card, but good idea to check for anyone else who has this problem - thank you

Printing stand alone from a SD card is the best way to avoid power and network issues.


text:
Material for printing orthotics
I noticed foot arches are already digitized, but custom arch supports are usually expensive.  PLA and ABS aren't the best material for printing arch supports, especially if they replace the shoe's innersole.
Is there a more flexible material for 3D printing that could be used for making custom orthotics?

The standard choice for this would be TPU, thermoplastic polyurethane.

TPU is a common filament material for use in fused filament fabrication 3D printing due to the fact that it is an elastic thermoplastic which makes it ideal for printing objects that need to be flexible and elastic.
...
Properties of commercially available TPU include:

high abrasion resistance
low-temperature performance
high shear strength
high elasticity
transparency
oil and grease resistance

In addition to TPU, there are plasticizer-modified PLA filaments with similar flexibility, but not necessarily with the other nice properties like abrasion resistance. I've printed with one from 3D Solutech and had good results, after figuring out what to do about stringing.
Also, it's possible to achieve a decent degree of flexibility merely with printed geometry, rather than special materials. It's possible that PETG with an appropriate geometry could work for your application.

https://www.simplify3d.com/support/materials-guide/

An alternative is to use PLA, ABS or PETG to print a positive product to make a mold, or print a negative mold and create a more flexible foot arch support from something more flexible than TPU, e.g. silicone rubber.

This is another good option. You can get somewhat softer TPU (which is of course increasingly hard to print well), or use infill geometry to achieve a softer print though if you want to print directly.

Armadillo by Ninjatek is perfect with 100 % infill and 6 layers 6 walls and 6 the other thing? As a foot pharmacist I can say the cost is associated with the education as pedorthic modalities are different to each person.  Ideally it would be easy to 3D print arch supports,  but it would also be easy to "hurt" the person wearing them.  buy a book on pedorthics before u wear them!


text:
How to add extruder to RAMBo Mini
I have given up on getting the RUMBA board to work. I tried to add a P.I.N.D.A. (or PINDA) probe, but that didn’t work. I tried to add a BLTouch sensor, but that didn’t work either. Now the RUMBA board is not communicating with my PC.
So I have moved on to using a Mini-Rambo but the one drawback is that it only has one extruder capability. I would like to know if there is any way to add an extruder to the Mini-Rambo. Whether it be a separate board or soldering or something. I am open to anything.

This question needs more information to answer. E.g. some pictures of the board and the brand. Please add information by [edit].

It sounds like you should post another question (or two), relating to why you can't get your RUMBA board to work :-) One for the PINDA and one for the BLTouch. When/if you do, please include in your questions, what exact steps you have tried and what did not work.

I would say that the clue is in the name, MiniRAMBo. The Mini part is related to its diminutive size and reduced functionality.
Extending the board would require patching in a secondary board to the MiniRAMBo board via pins1 that may or may not exist, and would probably be more trouble than it is worth.
Looking at the board layout certainly shows that there are not any readily available connections for such an expansion.

If you want two extruders then the RAMBo would be a better bet, as it has 5 stepper motor driver outputs. It would certainly be easier, and quicker (as well as cheaper) than a MiniRAMBo plus a secondary daughter board).
That said, as the MiniRAMBo has two Z-axis controllers, it may be possible to repurpose one of them, if they are wired independently of each other and separately controllable. Although these lines suggest otherwise:

It has 4 stepper drivers and 4 mosfet switched outputs.

and

Differences from Rambo
MiniRambo has:

4 stepper drivers vs. 5

and

Motor Drivers
4 A4982 1/16th microstep motor drivers(2 connectors on Z for Prusa
Mendel and other dual Z printer designs)

So, it would appear that the two Z axis drivers are wired together.

1 By pins, I mean external board pins/connectors - rather than the pins of the µController itself

The two Z connectors are, in fact, controlled by a single driver. I also thought it is the mini-Rambo, therefore the request to the OP to expand the answer. That board is very limited, exposing more pins would mean soldering to the microprocessor, which is pretty impossible for most people.

I've added a clarification. Thanks for pointing out the confusing line :-)


text:
Does cheap "plasticy" blue painter tape actually melt when printed upon?
Leading on from Darth Pixel's photographically informative answer to Why does the painters tape have to be blue?, which showed close up the plastic fibers of cheaper versions of painters tape... as Darth Pixel himself questions:

is such tape melted in any way in contact with extruded filament?

In other words, does such cheap, low quality, tape use fibres made from a plastic which has a melting point lower than that of PLA or ABS? If so, does this cause the tape to stick to the 3D print?
Obviously the higher quality (manila/paper) based tapes would not suffer from this potential melting issue.
Does anyone have real-world experience of this? Any photos showing melting would be great.

IMO, even if there would be some melting, it has not very much to do with anything. The importance is that the friction between the tape and the melted plastic is high enough to stick, but low enough so you can get it off when cold. Blue masking tape is (relatively) cheap, abundant, and does the job, that's why it's so popular!

It really depends on the tape. In my case, I've used various types of blue painters tape in bed adhesion situations and have only had one occasion where it sticks to the part. (All experience is with PLA) Best advice I can give is give it a shot, and be sure to wait for the part to cool before removing it from the bed for the best chance at not having tape stuck to the part.


text:
3D Printers imported from China - avoiding asbestos exposure
Many 3D printers are made in China, and as asbestos is still legal in China (with large ongoing production it seems).
It is thus quite possible to end up with a 3D Printer that has asbestos parts in it.
Even though asbestos is illegal in some parts of the world (like Australia, though not the USA as far as I know), given the above, and the possible lack of care by suppliers and/or oversights during imports, one may want to do due diligence.
This becomes even more important if you plan to make modifications to your printer.
When speaking with even large producers, you may also get very conflicting answers ("yes part xyz has asbestos in it" vs "no it does not") - which further complicates the matter.
Asbestos testing is usually about 50-70 USD per sample, and often destruction of the tested item is necessary, so that is not a viable way either.
There are also heating elements used in printers which may be shielded with asbestos containing materials (as asbestos has good heat resistance properties).
How to avoid asbestos exposure with a high degree of certitude?

Welcome to 3dPrinting.SE! There's a couple of things here which are striking. First, in order for asbestos to be "bad", it has to be in the dust form. As long as it stays in a solid, no issue. Secondly, the only thing asbestos is used for is insulation. There's almost nothing on a 3d printer which requires insulating (except for maybe the print head, but there are other things which are used for this purpose). Thirdly, it would most likely depend on the printer being looked at. If you're wondering, look up Libby, Montana ... I lived there 9 years as a kid so asbestos is a known to me.

Thank you. The print head may be wrapped in asbestos containing heat shielding, the heated base board may have asbestos in it, etc. Those elements are in constant motion, and many abrupt motions at that. They are also often touched, disturbed and dismantled for upgrades. You are entitled to your opinion, and there is no need to quote your experience (others may have experience too!), but please do not state your view of reality as the truth, i.e. "there are other things which are used for this purpose" is a statement of fact, and it may be quite inaccurate. Let's wait for others. Thank you.

The print head may be wrapped in asbestos containing heat shielding, the heated base board may have asbestos in it, etc - that's quite a few mays. Do you have any actual concrete examples of products with asbestos in them, to back up your claims? That's not to say that it is never used, but I've never seen asbestos used in a 3D printer... however, maybe I'm just not  purchasing the same printers as you. Also, duplicating your question as an answer elsewhere is a bit unusual...

I know of not a single chinese printer that does so and I spend some hours a month checking gearbest and such for new printers. In fact, it's obviously cheaper to skip thermal insulation and that is what most printers do or at best use some kapton tape!

Here is one; stock CR10 Creality heating bed; https://www.amazon.com/ask/questions/Tx2ORK5BUBPR8MZ/ref=ask_dp_dpmw_al_hza

Even then (the only case retrievable online), a mat under the printer which is not going to be scraped and taken apart by you is perfectly safe. Asbestos is risky if inhaled, not if looked at.  https://www.asbestos.com/exposure/short-term/

How to avoid asbestos exposure with a high degree of certitude?

If you're not willing to do asbestos testing yourself and can't trust your suppliers either, then this is impossible.
That said, for most of the components on a 3D printer it is easy to verify they're asbestos-free (I've never seen a steel linear shaft containing asbestos). For the remaining components, you may be able to pick an alternative which you know to be safe, for instance an all-metal hotend without insulating tape, or a heated bed that's plain FR4 without insulation. If there are any components that you distrust specifically (such as a heater cartridge) you should source that from a trusted supplier.


text:
How to connect BLTouch sensor to Alunar M508 using LSEE 3D v1.0 board?
In the process of updating my printer (Alunar M508), I decided to add "Auto Bed Leveling" using a BLTouch sensor. After doing a lot of Googling:

I found firmware that will upload and work with printer in default configuration (without BLTouch)
Adding BLTouch configuration, the software compiles and updates the printer, I see all new options in menu and BLTouch on "power on" does a self test.

I know I have configured the power to the device correctly 2 power sources and ground but where I'm having issues is in identifying Servo0 and ZMax/Min on my board. So far the black and white wire are connected to Z axis "end stop" but I cannot identify where to connect the orange signal wire to. I cannot find pinout anywhere of this board.

The LSEE 3D is basically a RAMPS board (your linked source also shows that the used MOTHERBOARD is a RAMPS board: #define MOTHERBOARD BOARD_RAMPS_14_EFB), this implies that all pins of your board are the same as a RAMPS board. To connect the 3 pin header of the BLTouch sensor you need to connect the red wire to +5 V and the black wire to ground; the orange wire needs to be connected to an available PWM pin. As the LSEE board does not have many exposed (free) pins for you to use, you need to re-use one of the existing PWM pins that you do not use. An example is the pin nr. 2. From the pins_RAMPS.h file you see in the limit switches section:

//
// Limit Switches
//
#define X_MIN_PIN           3
#ifndef X_MAX_PIN
  #define X_MAX_PIN         2
#endif
It appears, from the image, that your board does have max limit end stop switches header pins available. What you could do is use the X_MAX_PIN for the BLTouch sensor.
This implies that you need to assign the servo pin to pin nr. 2.
From the servos section of the same pins_RAMPS.h file you see that the servos are either connected to pin 7 or pin 11 (depending on the board, your linked sources use the 1.4 version).

//
// Servos
//
#ifdef IS_RAMPS_13
  #define SERVO0_PIN        7   // RAMPS_13 // Will conflict with BTN_EN2 on LCD_I2C_VIKI
#else
  #define SERVO0_PIN       11
#endif
Using the linked sources, the 11 should be replaced with a 2. This implies that you can connect the orange wire to the "signal" pin of the X_MAX end stop connector.


text:
What grease to use for linear rails?
What grease to use on linear rails to make them stick as little as possible? I've tried so far:

WD40 (let’s not start a discussion about that please),
silicon spray and
some bearing grease called ‘motorex’,

but with all of them the rails stick quite much and don’t slide as easily as I’d hope.
Can someone recommend some good grease for linear rails (specifically the hiwin type, 12-15mm)?

Don't use grease, it is better to use a light oil to lubricate the rods.  A light oil will help flush out any dust and filament debris, grease will trap it.
I've used both light machine oil (like used for sewing machines) and PTFE based spray (Teflon). Grease is thick and will collect and trap dust and particles more easily than light machine oil.

Even high-end consumer printers use light machine oil, e.g. the Ultimaker 3 Extended I got came with a bottle of light machine oil for the linear guide rails. Their advice is to regularly add a drop of oil on each shaft once in a while (how frequent depends on how much your printer prints).

And even with light oil or PTFE or silicone sprays, always wipe off excess.

@CarlWitthoft Indeed, good to mention not to overdo the lubrication!

So the valve oil for my trumpet ought to work great.

A lot of machines are heavily lubed on the bearings, I'll admit I haven't actually ever lubed my machines and rarely have issues. Take a bearing apart and it will be heavy grease. But I also agree on the Valve oil.

@JoelCoehoorn That oil may be designed for brass and so not contain the anti-corrosion additives for steel that some light machine oils might.

Thin grease should be fine, also because linear rails have the bearings on the underside of the bar, so that collecting dirt is less likely. It has to be thin grease, however, not thick.

I have (what I thought was Silicon) spray that was given to me by the garage door installer to lube the rollers for my garage doors. I spray some on a paper towel and wipe the X, Y and Z bars with that. It is called Zep 70.
https://www.zep.com/product/zepcorporate/zep-70

Zep 70 is a soy-based penetrating lubricant that utilizes a renewable soy solvent. It provides excellent long-lasting lubrication, and superior water displacement properties. Zep 70 will penetrate quickly and clean dirt and grease. It will also protect against rust and corrosion. Zep 70 is packaged in a 24 oz. can with a net weight of 18 ounces.
  Utilizing a soy-based solvent, a renewable source, helps to conserve nonrenewable resources such as petroleum.
  Non-evaporative solvent extends life of the lubricant.
  Quickly penetrates parts frozen from rust or corrosion.
  Displaces moisture and condensation which can cause corrosion.
  Treated surfaces are protected from rust.
  Helps clean dirt and grease from metal surfaces.

Reading the can contents, the Lubricant part seems to be TSRN-80100428-5003
The guides seem to slide on the bars with this stuff. Can't find a google hit on it.
I also made a polycarbonate enclosure around my printer to keep dust from settling on everything.

This sounds like it is pretty much WD40

Part of it does, yes. Really slippery stuff on the track bars.

authors: سوپر مارکت تمشک


text:
3 vs 4 bearings for y axis travel
I have a Monoprice Maker Select Plus, where I'm doing the Gulf Coast Robotics carriage plate upgrade. I was watching through an installation video just to find any "gotchas" I might want to watch for, and the guy in video recommends removing one of the carriage bearings, going from 4 to 3. The idea is to get quieter, smoother travels, with less weight on the belt.
Has anyone else here done this for this model printer? Or for the very-similar Maker Select v2/2.1? Are there any downsides I should watch for? Everything I know seems to indicate 3 bearings are just better (the whole "3 points define a plane" thing), but if it's that simple, why go to the cost of shipping with 4?
Update
I did end up making the switch, and it has worked well. One thing I've noticed is markedly increased ringing/ghosting. However, it should also be noted I switched to a stronger (heavier) build plate at the same time, and that likely is also contributing.

As Oscar suggests, removing the 4th bearing eliminates a major source of stress or binding, because it's difficult to place four points into a single plane.

@joel-coehoorn My printers has 4 bearings to avoid vibration on the corners not suported like 3 points, on a flat surface is easy to get a single plane.

Ideally you would use three bearings opposed to four. In principle you will only need 3 fixtures to get a stable reference frame. Look at how most Prusa i3 "X" carriages are constructed, they also have just three bearings.
Three bearings are way more easy to line out (especially with tight tolerance bearings), with four bearings you will get binding much more easy than with three.
I've been using three linear (self printed tight tolerance acetal/POM) bearings on the moving bed (Y direction) for quite some time on a Prusa i3 type of printer made from 2040 Aluminium profiles.

A similar reasoning applies to fixating the heated bed/glass slate, only three screws are necessary to define the reference plane. This is how my CoreXY heated bed is connected to the "Z" platform (a slate of glass is perfectly flat as a result of the production process).

I went with three bearings. This is now one of 4 total changes as part of a significant re-fit for my printer (carriage plate, fewer bearings, advi3pp firmware, and belt tensioners all at the same time).

as a side note: with 3 bearings, one can use one excentric nut to dial in the force on the beam.


text:
What do I need to do to recalibrate my printer after updating the firmware?
I just updated my Maker Select Plus from the stock (I believe RepRap-based) firmware to Advi3pp, which is Marlin based. The printer starts up and everything seems okay, but I haven't actually tried a print yet and there was a message during the upgrade about deleting incompatible settings.
What do I need to do to recalibrate the printer following the firmware upgrade?

If it is Marlin based or RepRap based, many parameters are stored in EEPROM memory. A G-code command M502: Read parameters from "configuration.h" would reset all parameters that can be changed to their default value as defined in your configuration file. Don't forget to follow the M502 command with a M500 command to store the loaded parameters to EEPROM. This would overwrite all previous settings.
From the linked source, M502:

This command resets all tunable parameters to their default values, as set in the firmware. This doesn't reset any parameters stored in the EEPROM, so it must be followed with M500 if you want to do that.

You can send these commands over a terminal interface to the printer using applications such as Pronterface, OctoPrint, Repetier-Host, and probably many more, or store the commands in a G-code file (e.g. a text file with a .g extension) and print the file using an SD card.

Marlin also offers to "Initialize EEPROM" in one of the display submenus - this can be used to reset the settings to default as well.

@towe Indeed, thanks for the addition! But not every printer uses a display, G-code always works.

Looks like I don't need to do anything. I printed a 20 mm calibration cube, and aside from some elephant footing it came out as clean and as close to the model dimensions as anything else I've ever put through the machine, with no changes.
So I'll recommend this as a first step to anyone else: start a 20 mm cube going, watch it closely early on to be sure you're getting adequate extrusion and bed adhesion. If it fails here you may need to adjust settings. When it's done, measure it and see where you are. You might not need to do anything else.


text:
How do I concave an image to create a 3D file for use in a 3D printer?
How can I print an embossed image in a concaved shape?
Like a big saucer. I will use this an a mold for a project.
So far I've found lots of software with huge spread of features. It's sort of overwhelming. There is lots of ways to create images into 3D printable objects but to add the extra step and concaving that image is harder to find out.
How would you do it? I'm open to suggestions.
I'm new to 3D printing and would really appreciate the help.

What are you using for your modeling software?

I have not selected a modeling software. I'm a programmer and I work with software everyday therefore I'm open to tryout anything.

http://3dp.rocks/lithophane/  can do the interior of a cylinder;  I haven't found a free site that will project into a sphere, but I strongly suspect you can take a planar model and use one of the standard CAD/mesh programs to make it spherical.  Maybe search YouTube for tutorials on "convert plane to hemisphere" ?

If you know Python, maybe this link   https://www.thingiverse.com/thing:2770219  or (I have not tried it)  the spherical projector at  http://maker.dongguk.edu/

What you describe, sounds like you want to create a lithophane; a pattern etched or engraved on a thin translucent base material (in your case a bowl) that can only be seen clearly when backlit with a light source behind it. Apparently you want to use it for another purpose.
Special software and or scripts that transform the image to the base material exist. An example is e.g. this sphere which becomes a globe when lit from the inside. Recommending a tool for creating such bowl is a little out of scope as these types of questions become outdated very quickly as technology changes or tools cease to exist. With the provided information you should be able to find software that is able to provide what you want to do.

You may want to look up https://3dp.rocks/lithophane/ it lets you do things like that

That link was given in a comment previously. It would be helpful if you could summarize the article and maybe give your experience if you have used that technique.

Hi and welcome. This is a link only answer, and when the link dies your answer will not be much use. As such, it may be deleted. If that happens, please summarise the information from the link and flag your answer to be undeleted.


text:
Linux software for laser engraver
I am searching for a Linux software to control the 3000 mW laser engraver depicted below. It's a common model you'd find on AliExpress, Banggood, etc. under different brand names.
I have already tried nejePrint, LaserWeb, and EzGraver, but they don't work. Any ideas?

Did you have any reason to believe it would work under Linux? If you buy something unsupported then you are the support. These things don’t just automatically have Linux drivers, someone has to write them. If you get any useful messages when you try connecting it you might be able to ask on a Linux forum and see if you can get it to work. Also you’re going to need to be a lot more specific than “it doesn’t work”.

You say you've tried all the different software listed, but are you sure it's the software? How do you know the printer itself isn't defective?

The literature clearly says it does not support *nix systems.

This looks like a small Linux development project more than a laser marking or 3D printing project.  Although it could be fun to help, you might get better information for the first steps (such as connecting the device to Linux) at the UNIX StackExchange site: https://unix.stackexchange.com .  They handle Linux as well as Unix questions.

I just found https://github.com/aquamorta/kkengraver:

This software is intended to be used with a KKMoon laser engraver (3000mW). It comes with ABSOLUTELY NO WARRANTY. It may or may not work with an other kind of laser engraver.

Some good internet guy/girl reverse engineered the communications and dropped it into a nice Python script - web server included.

A program that lists as functional with Linux is Lightburn. It's new to the laser engraving world and supports GRBL type controllers as well as Ruida brand and possibly a few others. If you can determine your controller, you're a step ahead of the game.
Directly from their site:

LightBurn
LightBurn is layout, editing, and control software for your laser
  cutter. With LightBurn you can:

Import artwork in a variety of common vector graphic and image formats (including AI, PDF, SVG, DXF, PLT, PNG, JPG, GIF, BMP)
Arrange, edit, and even create new vector shapes within the editor, with powerful features like offsetting, boolean operations, welding,
  and node editing
Apply settings like power, speed, number of passes, cut order, brightness & contrast, dithering mode, and much more
Send the result directly to your laser cutter

LightBurn is a native application written for Windows, Mac OS, and
  Linux.

I'm a satisfied Lightburn user, not a company representative.

Not a native Linux application so I dunno if it matches your use case, but the driver and control software "Laser engraving machine K4 V2.2" that was bundled with the printer on a USB stick works fine with Wine!
I'm running Debian Bullseye/Sid and I'm using version 5.0 of Wine. I started with installing the driver simply by running wine driver.EXE in the correct folder on the USB stick. The control software, however, seems to need .NET to run which it says by prompting you to install "wine-mono". After a bit of googling I found out that installing .NET using the command winetricks dotnet45 worked fine. After this you can simply run the software using wine Laser\ Framework4.exe.
I'm sure this is also doable using the GUI, but this is the way I did it. Also, maybe it works just as well with actually installing "wine-mono" instead of dotnet45 from winetricks.
EDIT: I can't find a license for the software on the USB stick, and I also can't find it online so I refrain from uploading it. OTOH, the USB stick is chock-full of logos of different brands so I doubt the authors are even aware of international copyright laws. Maybe I could send the software to you personally but I wouldn't host it since it could even contain malware

I also have one, when you plug it on your linux computer, there is a CH340G usb-serial chip inside, a serial port should be available at /dev/ttyUSB0, and you can send a right BMP file via this serial port.
Maybe EzGraver would work?
https://github.com/camrein/EzGraver

Hi, and welcome to 3DPrinting.SE! The OP tried EzGraver, but that did not work for him unfortunately.

I have a similar machine and you won't find a Linux software to control it. You won't find a Windows software either, except the one shipped with the machine. I sniffed the traffic on the USB port and the control is proprietary.
The good news is the included software runs on Wine, but I did not get to serve the COM-port to the program. Under Windows, the driver fixes the port to COM4: but I did not find out what the exact name is (capitals or : or other parts) that the program expects to symbolicly link the port to /dev/ttyUSB0. You might have better luck. When sym-linking the port doesn't forget the permissions, that's another trap.

The best is Kiri Moto.
I use CNC and the stack idea is very comfortable.
Laser and FDM, SLA are available as well.

Welcome to 3D Printing SE and thank you for your contribution. When you get a chance, please take the [tour] to understand how the site works and how it is different than others.


text:
What does nozzle size affect besides line width in, e.g., Ultimaker Cura?
The Ultimaker Cura documentation says

Tip: If you use an unavailable third party nozzle size, set the line
  width to equal the nozzle size.

I sliced an object with a 0.3 mm line width. When the nozzle size is 0.4 mm, the results are almost the same as when the nozzle is 0.3 mm. The filament usage is slightly different and the gcode files have similar, but different, coordinates throughout.
What does nozzle size really do besides suggest the line width?

Well, it does affect the anticipated extrusion rate and thus the rate at which the raw filament is driven into the hotend.

@Carl, that was my first thought, but I don't think it's correct. The amount of filament needed for the line width doesn't depend on nozzle size. The extrusion distance times the filament size gives you the volume, which must equal the layer height times the line width, regardless of nozzle size.

true - I was thinking more of the ease with which the combo of extrusion and motion speed could produce a reliable line width.

Searching the CuraEngine source, the only places I can find where nozzle size is used directly involve some arcane logic for merging of infill lines, such as:
https://github.com/Ultimaker/CuraEngine/blob/05e93dabce9e863b8742fd69ed87717e1594e7a9/src/MergeInfillLines.cpp#L124
So essentially, yes, nozzle size mainly serves as a default value for the line width settings.
However, in general it's not always possible for line width different from nozzle size to be honored.

For line widths smaller than the nozzle, motion along a path where the material being deposited has proper adhesion is required to stretch the material and prevent it from retaining the width extruded from the nozzle, and small lines already printed are likely to be damaged by the nozzle when attempting to print additional small lines in their vicinity. In particular, you won't be able to print small details significantly below the nozzle size just by extruding less material.
For line widths larger than the nozzle, compression against an existing surface is required to prevent the extra material from just sagging down rather than expanding horizontally. In particular, line widths wider than the nozzle are unlikely to work right in the presence of overhangs.

Also, as noted by Tim Kuipers in comments, there are places outside the source, but rather in the json-based configuration tree, where nozzle size plays a role in the defaults and warning ranges for other parameters. Those are mostly line widths, but

The nozzle size can affect the values of the following settings besides line width in fdmprinter.def.json: Outer Wall Inset, Outer Wall Wipe Distance and Minimum Support XY Distance. Other than that it only influences the conditions under which setting-values give you a warning.

Does that imply that you can change the "line width" setting when you swap out nozzles and ignore the nozzle size? Cura makes it much easier to access "line width" than "nozzle size" at the moment.

@Kayvon: I would guess that it's safe to do so, but that's probably an accident of the current implementation rather than something you can rely on.

This answer is actually wrong. You shouldn't look at the CuraEngine source, but you should look at Cura/resources/definitions/fdmprinter.def.json There are 65 occurrences, so that's quite a lot.

@TimKuipers: those are essentially just using nozzle size as default line width.

@R.. yes but those settings will then change when the nozzle size changes, so that is something the nozzle size setting does.

See "besides suggest the line width" in the question.

The nozzle size can affect the values of the following settings besides line width in fdmprinter.def.json: Outer Wall Inset, Outer Wall Wipe Distance and Minimum Support XY Distance.
Other than that it only influences the conditions under which setting-values give you a warning.

@TimKuipers: Thanks. Added that to my answer with credit to you.


text:
R3 Insights into industrial scale claims
Does anybody know anyone from the R3 team or have any insights  into their scalability and reliability claims?
The format and potential cost savings are appealing...
We are looking for an industrial scale 3D printing solution for the connectors that make up our TWIND Power Exoblades and R3 looks like a cool startup, on their web page at least
https://r3printing.com/
https://discordapp.com/channels/532618939486699520/532622198133882880
https://discord.gg/JFxAXzd
r2

They make some interesting performance claims, with 0 hard info to back them up. One wonders who they're using as the reference for "competition".

Agreed, I am looking elsewhere but keeping an eye on them as well beyond the website spin..


text:
CR-10 randomly pauses for a few seconds
I thought I have already had and fixed every problem one could possibly have with a 3D printer. Guess I was wrong.
I haven't used my Creality CR-10 for a few weeks, everything was working the last time I tried. Today I wanted to print something minor and the printer just randomly paused a few times in the middle of the print.
To be exact, it seems that after a few G-code commands have been executed the printer just freezes for like 10 seconds and then continues like nothing happened. This occurred a few times and every time the nozzle is melting the surrounding plastic and extruding a little which ruins the print.
I have tried:

Print from SD Card
Print from Laptop via USB connection to Ultimaker Cura
Print different models at different settings

My theory is that either there is a core problem with how Ultimaker Cura exports the G-code files or something is wrong with the printer software. I thought that maybe re-installing the firmware might fix it but I heard that that is a risky process. What do I do?

Is there any real problem with the print itself or does the printer miss steps when it does this?

Is it randomly pausing, or after each layer? Maybe the minimum layer time setting has been changed by accident.

Ok I fixed it by using Cura 4.0.0 instead of Cura 4.1. I checked again and found that the delay of ~10 seconds occurred every time right before the print head would go to a new object and again when it arrived. So when finishing the skirt it stops, when arriving at the new object it stops. I haven't found any setting that would cause this so I will try to make a bug report.

Have you examined the G-code?  If there is a long sequence of "no-op" g-codes, or a pause command (G4) there would be a stop.  Are you sure it has stopped?  Perhaps it is moving slowly?  The g-code would tell the tale.  Is it possible that you have z-hopping turned on, and that the z velocity is extremely slow?  I guess in summary I would examine the g-code.   It is likely that the printer is behaving correctly, but the slicer is slightly misconfigured.

@EVARATE  before reporting a bug, make sure that all the preferences and configuration values are the same in both versions of Cura that you're trying out.

I also looked through the gcode and neither "G4" or "no-op" was anywhere in the file. The steppers don't seem to move at all, not even slowly. Also I always used factory settings of 4.1 and 4.0 and only made changed in layer height and enabled ironing but nothing else. I haven't made the bug report yet because I didn't have time to make a deeper comparison anyways. Thanks for all the answers though.

I suggest you use Pronterface or Octoprint to read out a graphical output of the hotend temperature. If it is inconsistent and drops too low at times, it might cause safety halts, as it waits for the hotend to heat up again.

I am seemingly having the same issue only on Cura 4.3. There is no "Maximum Z Speed" anywhere on 4.3 so how can I fix this? As talked about above I just checked my "minimum layer time" and it is set to 10. I have also used another slicer and this same issue keeps happening it just messes up differently. I've also tried printing from SD card and OctoPrint. Same issue... How could this be my slicer if this same thing is happening on a different slicer than Cura? Please see also CR-10S Pro pausing and starting again.

Edit: The z-hop problem has been fixed in Cura 4.2.

This is a known issue with Cura 4.1 when z-hop is enabled.
If you touch the z-axis motor frame while it is apparently stationary, you may feel it is actually moving.
The solution is to set a value (I used something like 250 in conjunction with an Ender 3) for the "Maximum Z Speed".
First you need to get the setting to be visible, so go to the "Settings" menu and choose "Configure setting visibility...":

Then in the "Print settings" panel:

The full story is available on GitHub at [4.1 - current master branch] Z feed rates #5753.

I experienced the same with 4.1. Everything went back to normal after going back to 4.0 despite that all settings were identical as far as I could see. I compared the two g-code files using a simple file comparison tool. They were very different, hardly anything was the same. I still need to figure out what they mean. The model and thus the g-code files are far to large to go through. So, I will have to use a simple and small model to start unraveling what those differences mean.


text:
Are large format prints more brittle?
Recently on one of her videos a YouTuber stated that prints from large format printers are more brittle than if you were to print them in parts and glue them together. This seems to contradict the testimonials from the customers of a large format printer, who say that they get good prints from those printers (which print have a print area of a meter square).
Would a print form a larger format printer be more brittle than a print made of smaller pieces super glued together?
(with all other aspects being equal e.g. the nozzle, the temps, the material and the shape of the object).
The YouTube didn't cite any source information to back up her claim.

If you break up a large piece into multiple smaller pieces and properly glue them together, you basically add stiffeners (as a result of printing walls). This could lead to a more stiff model; this might have been confused by calling large prints more brittle opposed to constructed models.
If printing is conducted at similar conditions on large printers, there shouldn't be a reason why the model becomes more brittle unless the conditions aren't the same. But that would be true for printing at small printers too, e.g. if one print was printed in a draft.

@ Oscar That assumes the same fill percentage on both, so that the outer shell of the pieces glued added to the internal structure.  You could compensate by having a higher fill percentage on the larger one piece models.

@PerryWebb It isn't a good idea to compare apples and oranges. But indeed that is possible, the question, or the (non existing) reference to the YouTube video is not clear on that. I merely provide a plausible explanation.

The pieces having printed as outer shell glued internally definitely adds to a stiffer structure as well as more material used printing.

So it could just be the internal structure. Makes sense. This is something I have to figure out how to test.

In that case, the solution should be to actively add the required internal stiffness (for example by using modifier meshes in Slic3r / Prusa Slicer) instead of printing it in parts and glueing it together.

I'd recommend getting the object to fit together by design, rather than glue - though I tend (if the item is never to be disassembled) use Zap-a-gap - that stuff sticks like crazy though you must not squeeze the parts together but let it naturally sit.

This is good advice, but it doesn't answer the question Are large format prints more brittle?


text:
Material for printing flowerpots
I want to print a flowerpots, for advanced watering system.
Plants are going to be eaten.
What is the most suitable material, when we consider the fact, that we do not want to just make forms and do clay flowerpots(which may seem most healthier), but having them directly printed.
What are the temperatures that makes plastics emit dangerous components in surrounding water, and what are those components?
Is there some "totally safe" material out there? I was thinking of PLA or PETG, because I've already heard that ABS is not safe for edibles.

I'd say PLA is a good choice.

Note the threads mentioning that PLA becomes brittle with moisture.  So, if you use PLA, you will need to consider the pot loosing flexibility.  Thus, it needs to be thick enough not to flex.

Every answer has it's benefits, is there way how to make two answers checked?

From https://www.3dhubs.com/knowledge-base/pla-vs-abs-whats-difference
PLA is stable in general atmospheric conditions and will biodegrade within 50 days in industrial composters and 48 months in water. ABS is not biodegradable, however it is recyclable. PLA is regularly used for the production of food related items, however confirmation by the filament manufacturer that it is safe to do so is recommended.

ASA is better if exposed to sunlight, but not easy to use. https://www.simplify3d.com/support/materials-guide/asa/

I printed some pots for sprouting seedlings this year from PLA.  A square array of pots with tiny drainage holes in the bottom.
The array filled the bed of a Prusa3d i3m3.
The seeds sprouted, except for the ground cherries, which I think failed because the seeds were bad.
I had good germination rates for tomatoes and basil.
According to the FDA, ABS is generally safe for food, although like any filament the pigment and any added chemicals may be contraindicated for continued health.

What colour is "without pigment"?

Most filaments are available in natural.  They are typically translucent, some tend to be slightly yellow.

Given the tendancy for extrusion 3D prints to be porous, aside from any potential health/ingestion issues, I'd recommend lining your pots after printing. You could use an epoxy that's food-rated, or a thin layer of concrete, or even sheet metal if you have access to a bender (or aluminum foil, for that matter).
So far as temperature-dependent outgassing, that's not an issue unless your garden will reach temperatures over 150 Celsius :-)


text:
Possible causes of print defects?
I'd like some advice regarding defects on my print :

Here some details :

Printer CR-10 S, nozzle 0.4
Material PLA
Bed 60, Hotend 215, 50 mm/s speed
SLiced with cura 4.1, 5 walls (i can provide more detail of the profile if needed)
Layer height 0.1
modeled on fusion 360
The surface where the defect sits is actually tilted 45 degres

Thanks !

There are many possible causes for printing defects, but the easiest one to eliminate is dirt. Always use a filament cleaner to prevent dirt from entering the extruder. There are plenty of designs available on Thingiverse. Always keep your nozzle clean. After pre-heating mine, I clean it (carefully) with a folded paper kitchen towel. It may also be worthwhile doing a "cold pull", if you suspect that you have dirt in your nozzle. Finally, you should check that filament is not leaking out between the nozzle and the heater block.

It's true that the filament littly scrub against soft wood, maybe some bit got dragged along, i will add a filament cleaner, it can't hurt anyway ! Thanks for your help

This could be a problem with the filament rather than the printer.
If the filament contains air bubbles, they will heat and pressurize.  The additional pressure can increase the flow rate for a moment as the molten material in front of the bubble is expelled.  The flow rate decreases after the bubble pops through the nozzle because the now-empty space needs to be filled by the extruder pressing new filament into the melt zone.
If this is happening, you might hear little pops.
Alternatively, the filament may have absorbed water, which can convert to steam and explode out the nozzle like a bubble would.
Drying filament isn't hard.  I use my household oven at it's lowest temperature, which is typically about 160 degrees Farenheit.  This is high enough to slightly soften PLA, so don't go any high than you must.  Bake the filament for an hour, let it cool before handling it and try again.
The filament may not be quite as round after baking, but the cross-sectional area shouldn't change.
If the problem is from bubbles, there isn't anything you can do to fix it.  If it is from water, you can fix the filament.  I'd suggest baking the filament and seeing if anything changes.

My roll is almost done, if the next one have the same issue i'll try baking the filament (have to be discrete, not quite sur the wife apreciate filament in the oven :) thanks !

I'm sure you can make a good explanation for the plastic in the oven.  By now she must realize that you aren't an evil genius.  Don't do it on the grill.  Controlling the low temperature may be much harder.

authors: اکرم ترخوانه


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Slow down first layer above infill in Ultimaker Cura
In Ultimaker Cura, is there a setting to slow down just the first layer (or two layers) covering over the infill?
I'm not talking about the top layers, since you may have infill covered over during a lower section of the print. And I'm not talking about bridging, since this isn't a true bridge, and quick testing shows the bridge settings don't seem to control this. I'm also not talking about the whole layer, since you may have just a section of a layer involved with covering the infill.
What I want, is, whenever a print transitions from infill back to shell, that first section of shell above the infill (and maybe also the next layer going the opposite direction) should be slower.
What I've observed is this layer prints at the same speed as other shell sections, which can be too fast at this point for complete coverage, leaving a stringy section. This won't be visible later, but it does matter for strength and potentially quality; if expected filament isn't deposited it has to end up somewhere. Slowing down should help get a cleaner layer.
Can Ultimaker Cura do this? I don't care which version. For completeness, what about other slicers? Even if I normally use Cura, I might be tempted to use a different slicer that can do this if I have a part where it really matters.

Yes that is probably possible, you'd need to look into the properties concerning overhang, e.g. speed. I don't have access to Ultimaker Cura now.

I don't think so. Overhanging the infill (logical solid interior) of the model is not considered overhang by Cura.

Cura can do this. It's a bit convoluted though. Here's what you need to do:

Load your model / scene in the build plate.
Load an additional cube and make it as big as the entire build plate so that it overlaps with everything (in the preferences you may need to disable "Ensure that models are kept apart).
Select the cube and go to the per-object settings tool.
Change the cube's mesh type to "modify settings for infill".
For the cube, set Wall Line Count to 0, Top/Bottom Thickness to 0 and Top Layers to 1. This effectively makes the cube add one additional layer on the top side of all infill volumes.
For the cube, set the Top/Bottom Speed to your desired speed for the one slower layer.
(Optional) In the normal settings panel on the right, set the number of top layers to be one less, so that you get the same number of top layers again.

Presumably this also works for setting other properties of the first top layer, so you could print it like a bridge?

As far as I know, Cura has no option to do this. Conceptually Cura treats the model as a solid, so that the material over infill is not "overhang". However, you may be able to hack it by using the "magic mesh surface mode" feature under "special modes", to treat the model as a surface rather than a solid, then enable support and use the same model as a mask for where support material should be printed, and print support as infill-only. Alternatively you might just print a second copy of the model as infill-only (0 walls and 0 layers of top/bottom skin) in the same location.


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Should I cooldown before shutdown?
I am working with Ender 3 Pro and in menu it has an option to cooldown. Is there any need to cooldown 3D printer before shutdown or can I just shutdown without cooldown?

Welcome to 3dPrinting.SE!

Depending on what material you print it it most likely a good idea to let the hotend cool down before shutting off the printer (fan).
For example if you shut down the printer right after you print a PLA part, at 190 - 220 degrees Celsius, your hot end will still be that hot and will suffer heat creep without the fan running. The next time you fire up your printer the hotend will be jammed and you will need to clear it before starting a print.
This is obviously situation dependent but in most cases you should let your hot end get below the TG (glass transition temperature) of the material before turning off the printer.

That option you are referring to, is meant to manually shut down power to the heated bed and hotend, there is no timed cool down period other than you timing it. This is a handy option if you fiddled with either the bed or the hotend; e.g. to insert new filament.
A cool down period can be very useful depending on the printer. Those cold-end cooling fans usually are very noisy, so people cut them of (that is not always possible/wise, but is being done out there), disable them after printing or shutting down power of the printer as a whole. Some type of hotends are prone to have heat creep up the hotend and  soften the filament so that it can clog up the hotend. I've seen this happen on Ultimaker printers where the cooling fan was not spinning because some fine strings where sucked up.
To minimize the noise level of such cold end cooling fans you can put them on a relay switch and have e.g. OctoPrint schedule the print to be on for e.g. 2 minutes after a print failed or finished, works perfectly, and then you have your cooling down schedule/period.


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Should I include fillets on my 3d printed parts?
A fillet is like a rounded corner but on the inside of the corner.

Does it make a difference (structurally) to use fillets on a 3d printed part?

If your part needs structural support, then the word is: absolutely. Fillets provide the added support when you need it. If your part has a meeting line which is sharp - 90° (or perpendicular), there is a natural stress riser in your design. This is a weak spot where a crack can form. If strength is needed and the fillet won't interfere with the design, it's definitely something you should include with your part.

Chamfers (flat corner cuts) are a better option for printability, unless the corner is in the XY plane.

@Trish - chamfers are not really any more printable than a fillet In my (admittedly limited) experiance, and they still leave two stress points.

Please check out Makers Muse on fillets & chamfers.

@SiHa Fillets are less printable than chamfers (depending on the printing plane), please read this answer.

Fillets in X-Y plane (i.e. between two vertical surfaces) work great for 3D prints and increase the strength a lot. They usually also improve the print quality, because the print head can keep a constant speed in the curve instead of slowing down to a sharp corner.
However fillets that extend in Z direction (i.e. between a vertical and a horizontal surface) suffer from layer artifacts. Sometimes they can look worse than a sharp corner would. While they do still increase the strength significantly, they are not as strong as similarly sized fillets in X-Y plane are.

So the nozzle can keep it's speed around corners better, and X-Y fillets are better than Z fillets. Kewlio.


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How to fix wall separation in 3D prints (gaps in between wall perimeters)?
The print is very solid except for the 4 walls.
From the top, I can slide a paper down to the bottom. This is ONLY between the walls, the rest of the print is solid. The filament is PLA 1.75 mm.
But the bottom is solid, no gaps.
I have checked the usual problems on Ultimaker troubleshooting photo gallery, but I can find anything similar.
Any advice to fix this would be very welcome.

Print settings:

Increase the infil overlap.

Where do you put the paper in between: between infill and the walls, or in between the walls? If the first is applicable, the previous comment holds, else I'll write an answer, I've fixed this for my printer. Please add some basic information on temperatures, speeds, filament type, etc.

To fix this, I had results with the following way:

Change your extrusion width from being equal to your nozzle size (0.4 mm) to slightly larger (I use 0.45 mm). That way you better combat the shrinking of the filament.
Having the Print thin walls setting activated to force the printer to print intermediary walls if there are areas where less than the prescribed wall thickness for a single wall fills in spaces that are as a result of the wider outer walls left. The result for a 1.2 mm wall, the central part is a 0.3 mm zigzag.
Lower the extrusion temperature a tad as hotter filament shrinks more on cooling! For PLA about 200 °C is my sweet spot.

Additionally, there are extra steps that could be taken:

Finally, you could play around a little with the extrusion multiplier to try to get rid of the tiny bit of under extrusion you have.
Calibration could help too.

Are you sure "Print Thin Walls" (fill_outline_gaps) does what you think it does? My understanding is that it has nothing to do with filling a "remainder" between walls. Cura uses low-extrusion zigzag for this in place of an additional low-extrusion wall, and this is controlled by fill_perimeter_gaps, "Fill Gaps Between Walls", which is on by default but omitted for really tiny gaps due to filter_out_tiny_gaps. AIUI, the behavior of fill_outline_gaps is to keep regions of the sliced outline narrower than the nozzle width, extruding w/ low flow.

@R.. I have had the issue before, flicking it on and going 0.45 mm extrusion fixed it.

Is it possible just the 0.45 mm line width fixed it? I've been trying to better understand what the gap options do and think (thought?) I did, so I'm interested in your results here. I actually had very bad results with fill_outline_gaps causing blobs and stringing (mysteriously Cura ignored my retraction settings for this layer?!) on top of a horizontally-printed threaded bolt by printing an extra top layer where just a tiny portion of the thread much smaller than 0.4 mm was present.

@R.. reordered, added explanation why it helped for me

Still, are you sure you didn't mean fill_perimeter_gaps, "Fill Gaps Between Walls"? That's the option that seems to be documented as doing what you want, and that seems to do it for me.

@R.. I did switch "print thin walls", which might contain flipping the other.

Now that print settings are shared we can see that this problem is not related to too fast printing (only 20 mm/s) or too low print temperature (210 °C should get PLA fluid enough). To explain this, a low temperature and too fast printing cause under-extruded lines.
There are 2 other causes that might be worth investigating:

Under-extrusion. From the top layers one can see that there may be insufficient material printed. Calibration of the extruder helps in this respect.
Inaccurate positioning. This may for instance be caused by loose belts or a mechanical defect.

I've experienced this too, especially with flex modified PLA filament. For that, fixing underextrusion and increasing temperature made it go away. Sadly Cura has no option to overlap walls slightly (if printed in the right order, this could be done without affecting dimensional accuracy) except possibly the outer one, so you really have to get extrusion rate calibrated right or this will happen.

Look for the horizontal expansion setting in Cura. By default it should be zero. The description includes this:

Positive values can help compensate for too big holes.

The "holes" here includes these gaps. You can set it to something very small (ie: .01 or .03, probably no more than .05) and that will likely be enough to get it to fill in those gaps.
Unfortunately, I only have a little direct personal experience with this setting, hence the probably/likely weasel words, and I can't give much real guidance on exactly how big or small you can go with this.

These gaps are not those kind of holes. The holes in question are negative space in the sliced layer, not space between extrusions.

The setting "horizontal expansion" is not meant for this purpose. Horizontal expansion should be used when print have a systematic deviation from the actual model size. E.g. a 20 mm or 100 mm box print as 20.4 mm and 100.4, you can use a horizontal expansion of -(0.4/2) = -0.2 mm.

What @0scar said. Also, I realize my above comment was somewhat terse and maybe subject to misinterpretation. "Horizontal expansion" is an operation on the cross-sectional outlines produced during the slicing process, before any extrusion paths are laid out. It may have an effect on gaps due to introducing new space for extra wall lines, skin zigzags, or infill that presses on the existing wall lines in new ways, but it's not in any way a predictable mitigation for gaps and will alter the dimensions of your print, usually in a bad way.

I had the same problem, through multiple models and different brands of PLA. I fixed it by setting the Material "Wall Flow" parameter (both inner and outer wall) to 102%.
Note: The outside dimension is still accurate.


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Monoprice printer: no files found on SD card
My monoprice printer was working; I then tried to format the SD card on a Mac, then it stopped working. I have now tried three different SD cards after formatting on a Windows PC, and still nothing works. Are there supposed to be files on the SD card itself like some kind of root files?

See the discussion at https://3dprinting.stackexchange.com/questions/7845/how-to-format-an-sd-card-for-monoprice-select-mini-v2 and see if it helps.

I've no idea why 3D printers don't like SD cards formatted by operating system utilities, but they don't. Use SD Memory Card Formatter to format your memory cards. Unfortunately, you have probably lost any data that was on the original SD card.
The SD cards that are supplied with 3D printers typically contain documentation, test files, and device drivers. However, these files do not need to be present for the correct operation of the printer. All that is needed is a correctly-formatted SD card containing the G-code files that you want to print.

This addresses the formatting of the card (like the answer in the linked question, can you comment on the root files part of the question? I've never heard of such files for printers.

I'm skeptical -- my A8 clone  is perfectly happy with SD cards I've formatted FAT32 via MacOS


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How to work with PETG? Settings, caveats, etc
We've been doing some printing with PETG filament on Ender 3 Pro printer and the result were awful:

Here are settings we used:

Extruder: 240 °C
Bed: ~70 °C (± 10 °C)
Speed: 80 mm/sec

There are a few types of problems that we had:

Initially filament did not stick to the bed - those 3 items in the middle of the picture are example of this issue. This got fixed by increasing temperature of bed to 80 °C.
At some point a piece would get dis-attached from the bed and would move around together with the extruder around - two prints in the upper right corner of the picture were cancelled for this reason.
Models are very rough, like a cheaply made snowball - that tiny model in the upper left is suppose to be a cattle-bell. Could you tell?

Additional info
Filament that we used indicated

extruder temperature 230-240 °C
printing speed 40-90 mm/sec
no info about bed temperature

Question(s):

What are some optimal, tried and tested options for printing PETG? (Temperatures, speed, etc)
What are some caveats/difficulties of working with PETG to look out for? (For example, I've read that PETG likes slower speeds. Is that true?)
Is it possible that the model of 3D printer does not work well with this type of filament? (I don't have much experience printing so I can't know)

The real problem was that I damaged the nozzle (most likely while cleaning it) in a way that increased the size of the hole. So, too little filament was coming out of too big of a hole, which caused such poor models. Replacing the nozzle fixed the problem.
I do not remember the settings of the top of my head. Generally advised settings for PETG (whatever they were) worked fine.

How did that happen?

@FarO Probably while I was using scissors-like instrument (I forgot how it is called) to clean up excess of filament that was coming out during warmup. I must have not been careful and cut off a tip of nozzle by accident. I didn't notice while I was doing it. That thing is so tiny. But looking back at what I was doing this would make the best sense. I was also trying to level the bed and used piece of paper to determine friction. Not sure if that could do any damage to the nozzle's tip (if not done carefully).

Slow down!
80 mm/s is much too fast for PETG. Try 45 or 50 mm/s instead, even for infill, supports, and other less-visible areas.

The Ender 3 can print PETG alright - in some regards, such as warping and adhesion issues, even better than PLA. But you do need the right settings. 230-240 °C is too low, especially at the extremely high speed you're trying - you're going to get serious under extrusion and likely stringing.
My PETG settings are 80 °C bed, 250 °C hotend, and normal 30/60 mm/s speeds 40 mm/s print speed for everything, and lowering fan speed to 40 % or lower (ideally off entirely unless you find you need it). Full speed fan will prevent bonding, and is not needed to avoid warping like it is with PLA.
Also make sure you have the first layer set to print slowly (30 mm/s or less), and make sure your gap between the nozzle and bed isn't too wide. You also need the nozzle to be primed well before the actual print starts. A skirt can do this but I prefer custom start gcode to print a thick priming line at the edge of the bed. Mine is based on Ultimaker Cura's default but only goes one direction rather than reversing and moves a lot slower.

I've read in a few places that the tubing for the Ender 3 can't handle 240c, let alone higher and will start to release toxins. Did you replace the tubing with a higher quality one?

@John: No, that's just kookery. Teflon doesn't even start to break down until over 250, and unless you get a lot hotter the amount will be minuscule. Your cookware gets a lot hotter anytime you burn something. These are the same folks who tell you you're going to get cancer cooking with nonstick pans.

Also there is no "higher quality one" I'm aware of, in terms of durability to heat. (Someone please chime in if I'm wrong on this part.) There are higher quality ones in terms of dimensional accuracy of inner diameter,  surface smoothness, etc.

Well I know for sure that above 235c mine starts to omit a very foul oder and is likely melting itself. I don't have the same issues at 230c which I'm now printing my PETG at.
I haven't seen a source besides yours saying that above 240c is fine on the ender 3 because they cheap out on the tubing. I've seen the Capricorn PTFE Bowden Tubing mentioned as a higher quality one that will handle higher temps fine without melting itself. Do you have any proof that all the other places are wrong and that that nasty smell is just fine for me?

None of your prints look like they are sticking well to the bed.  You didn't specify the bed material.  For many bed types, you might have success with Aqua Net hair spray.
Like any material, if it isn't solidly sticking to the bed, the print won't be good.
This probably is not related to your problem, but you may need to reduce the drive gear pressure or "pinch" of the filament.  PETG seems to be softer than PLA or ABS, and I've had problems where it was rolled out like pie crust by the filament feed gear to the point where it would not feed.  Reducing pressure, reducing retraction, and increasing the minimum extrusion between retractions helped.

Ender 3's stock bed is a buildtak clone and works great with PETG.

I just made an account to point out that you will scorch your PTFE tube if you listen to anyone here telling you to print at 250+ C. I have done this, it is a bad idea without an all metal hotend.
Not a lot of dumb things on here will actually give you cancer, but cooking your PTFE-liner will.

note that the PTFE will start to break down at 327 °C. However, it will detoriate starting at 260°C, which, wich some degrees of safety means you shall not print with a lined hotend at above 250°C. You won't create PTFE fumes till 327°C.

I use a fine round brass brush, similar to what you would use to clean a gun barrel, to keep my nozzle clean. The brass is softer than the nozzle material, so it doesn't damage it, and the bristles grab strings easily - you barely have to touch them.
I'm using SUNLU PETG filament in my Ender 3.  It sticks VERY well to the "Creality Original Ultra Removable Magnetic 3D Printer Build Surface".  I'm set at 70 °C on the bed.  Get your height set well. I had a ton of issues with nothing sticking until I got it dialed in. Now, it almost sticks too well.  I often have to remove the magnetic sheet in order to get larger prints off it.

Welcome to 3D Printing SE and thank you for your contribution. When you get a chance, please take the [tour] to understand how the site works and how it is different than others.

55 mm per second is the highest I would go with PETG.
Cleaning the nozzle more often helps.
Also check your PID for the nozzle temp, it could be inconsistent and PETG can be very finicky with temperature.

authors: รุ่งโรจน์ สายบุดดี


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How to make menus more responsive in Marlin 1.1.9
I have an AM8 with an MKS GEN 1.4 board with a Bowden extruder at the moment.
What I would like to do is to make my menus a bit more responsive, similar to what the guy at Lokster Space has done with ver 1.1.5 of Marlin with a tutorial how to do so. I've been through the file ultralcd.cpp but nothing matches what the tutorial is telling you to change.
The following link is the details for the upgrade: How to make the Marlin menus more responsive on Anet A8
Could anyone please help with my situation.

Supposedly, it's no longer necessary in a recent Marlin version, already the inline bool handle_adc_keypad() function from ultralcd.cpp has implemented a smaller (100 ms) time delay. You could lower the value of #define ADC_MIN_KEY_DELAY 100 to #define ADC_MIN_KEY_DELAY 50 to see if that has any effect.
Also, look for next_button_update_ms = now + 300; (4 instances) which employs a 300 ms time delay after buttons are pressed. Try lowering the 300 ms time delay.


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How to avoid nozzle from hitting the model?
When printing objects higher than approximately 8-10 cm, sometimes nozzle hits the printed model and knocks over it. After 7-8 hours of printing that's really annoying. I'm using Creality Ender 3 Pro with Ultimaker Cura. How can I avoid this problem?
As a note; it happens with thick, wide models without support structure too. I'm using Ender 3 Pro's stock magnetic bed.
Here are some photos of printed model.

I use Esun PLA+, the part was on baseplate without any loss of contact. It was like one layer missed its coordinates and then all corrupted.
I think it's not related with bed adhesion because for example for this model, it didn't knock over the model.
There is no roof for the model, I think it doesn't need any support structure. Here you can see the expected finished one:

Can you give examples of some models it happens with? You probably have both warping problems (bringing material above the nominal Z) and bed adhesion problems. Up to the point that printed, there should be no travel moves because the layers are simply connected. Is there a roof like the base that's getting started when it fails? If so the problem is likely failed bridging without support - the failed bridge creates string junk that curls randomly (sometimes up) for the print head (not just the nozzle) to catch on and drag.

What material are you using?  Often this "knock over" is due to warping or loss of contact with the baseplate, so that the nozzle isn't hitting the part but the filament itself is dragging the part along with the nozzle.  Every photo there sure looks like the part moved, as you can see strings which should have been over the end-edge. As one layer was skipped then that suggests a possible skip in the X or Y-drive. Not to be a buzzkill, but Ender machines do seem to produce more 'failed print' questions here than any other brand.

WIth a base like that, it should take some serious force to remove the part from the build plate, and I'd even worry about damaging the build surface if I didn't use a blade to separate it. I wonder if you have way too much distance between the nozzle at height 0 and the build surface resulting in poor adhesion. It's possible that you also have an issue like stepper skips/layer shift, as Carl suggested, but it's not clear which came first, the separation of the print from the build surface, or the misaligned attempted layers on top, and either could have caused the other.

Folks voting to close this, it's not a duplicate; rather OP's question is misstated. The underlying problem here is not the nozzle hitting the model but something else (either breaking off the build plate, or a layer shift or other problem causing junk material that the print head can hit).

If the Z axis is not level, it's likely that the screws holding the gantry to the roller structure on one or both sides are either loose or not square with the gantry. The ones on the right are easy to see and adjust, but the ones on the left are somewhat hidden between the gantry and the vertical rail, and only accessible after removing the whole assembly from the vertical rails, and only then with the short end of an allen wrench. Both sides have significant play if not tightened...

For the ones on the right you can let them naturally align with the tension of the system, and tighten them down once it's aligned. But for the ones on the left, you have to just get them as square as you can with the X axis gantry removed, either eyeballing it or using some shims and straight reference to hold the bracket in place while you tighten it down.

Unfortunately Ender 3's gantrys on Z axis are 3 wheeled gantry and it's almost impossible to level them with precision. There is always difference around 1mm

It seems the problem was because of Z-axis leveling (level of the X-axis), I found out that the right side was more than 3-4 mm below the left side when the Z-axis height exceeds around 8-10 cm. Below 8-10 cm, the two sides were even. I calibrated the X-axis by turning the eccentric nuts of the wheels and tighten them. I will try printing soon with some test objects.

There is a clear scar in the print that looks like the print head has hit it.  The scar is about 1/3 of the way up the straight return segment on the right side of the photo.
The OP has provided enough information to show that it isn't an overhang or bridging problem.
I don't see any cracks in the print where part of it may have separated and bent upwards.  I accept the OP's statement that the item is well attached to the bed.
What problems could there be?
The printer may have a Z-axis problem at that height.  Perhaps it exceeds the maximum Z-height, or perhaps there is some obstruction or debris in a lead screw that is preventing it from freely moving above that height.  The obstruction could be a cable that is too tight or an errant tie-wrap that hits something, or almost anything that interferes with motion at that height.
There is always the possibility of a bad wire (such as to the nozzle heater) that causes problems when the height reaches a critical level.
There may be a parameter change in the slicing software that is set for that height (or layer count).  There shouldn't be, but a default profile may have been changed.

There are options in Cura to avoid that the extruder hovers over printed parts when traveling. There is also an option to lift Z axis while traveling. Those options are hidden by default. You can only enable them in advanced settings mode.

This is true, but z-hop especially creates other problems - stringing, and/or blobs above the nominal printed height so far that the nozzle can hit while printing the next layer.

I wouldn't recommend this until we've verified that his parts are properly affixed to the bed and that his printer isn't failing to maintain proper z-position.

@CarlWitthoft how would you suggest to verify those?


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Must I start over if I change a dimension in Fusion 360
As a newbie, I have done some Fusion 360 tutorials and recognize I made a mistake in the initial dimensions.
Aside from starting the entire sketch over again, can I just modify the (beginning) rectangle dimension?

Welcome to 3dPrinting.SE!

If you enabled the history, you can easily go back in time and change the dimension in the sketch and then go back where you were. It would be even more elegant if you do not use fixed valued dimensions in the sketch, you can use parameters you define yourself and assign them to certain dimensions to create parametric designs. These values can be changed at any time to see your final design adapt to those changed parameters.

authors: ศราวุฒิ คุลไชสงค์


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Which 3D filament is 100% (or close to being so) food safe and non toxic?
I've recently bought myself a preassembled Prusa i3 MK3S printed and made my first projects. One of them was making a cup with my name on it. I want to use it to drink tea, water etc. I know, however, that I need to chose my filament wisely, as using the wrong one might be unsafe. I know that PLA for example is Polylactic acid which is a safe substance and occurs naturally in our body. Another thing is the dye, which can is a chemical substance I know nothing about. Do You recommend any specific type/model? Thanks.

@Greenonline Editing the question so significantly after it already has two answers isn't that great of an idea. Now the answers do not make sense any more. Moreover, there are thousands of different kind of dye so I think the current question is unreasonably broad.

Answer was moved to this question: Which are the food-safe materials and how do I recognize them?

I think this site will answer some questions about food safe 3D printing: 12 Vital Facts About Food Safe 3D Printing
PLA is not a good choice for hot substances because it will deform at hot water temperatures which is no good for a cup (very dangerous!)
I would recommend a filament like PETG, PETE, HDPE, and LDPE: What Plastics Are Approved for Food Contact Applications?
Those types of plastic require very high printing temperatures and an all metal hot end.  You don't want PTFE in your hot end when printing at those temperatures (265 °C) as it will emit toxic gasses.
I've seen food safe filaments for sale so it might be best to search Google for one of them to use.
Please keep in mind that printing anything will cause voids and gaps that will allow bacteria to grow.  Personally I don't think I would want to risk it for daily use items but a coffee/tea cup might be alright.  This is covered in the first link.


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Does PLA become brittle with age?
I tried to use an old spool of PDA and the filament would keep breaking.  New filament will discolor white but stay intact when you bend it.  This old filament would break off at a clean 90 degrees when you bend it with no discoloration.  However, our new material is Hatchbox PLA and the older is a different brand.

It becomes brittle when it takes up moisture, how much depends on humidity and time. The better you store it the longer it takes to become brittle.

Duplicate of https://3dprinting.stackexchange.com/questions/1404/can-aged-pla-be-refurbished ?

There are many theories why PLA filament becomes brittle. See the link in previous comment.