I don't know if using OctoPrint is an option. If so, there is a plugin that claims to do exactly this. And you could probably find a few more if you looked for them. Note that I have no first hand experience with this plugin, but I can vouch for OctoPrint being convenient and by default it shows a temperature graph.

It might even be relatively easy to write your own plugin to accomplish this. This will mostly depend on your comfort with coding in Python/JavaScript.

As a sidenote: if your printer is connected directly to your computer via USB, chances are pretty high it is a simple serial connection. Having multiple programs use this connection at once is not possible as far as I know.

This implies that you will not be able to have your current software send it G-code lines while having another one recording the temperature values sent back from the printer.


The OP was not able to reproduce the problem as can be taken from an edit to his question:

  Changed absolutely nothing, tried again and problem solved!

To honor the Q/A approach used on SE sites, this comment has been converted to a community answer, that once voted for will not make this question pop up once in a while.


This is a very well known issue that is caused by insufficient adhesion. The corners curl up during printing.
You should increase the adhesion by:

cleaning the bed (I use water and soap, others use isopropyl alcohol)
better leveling,
correct nozzle to build plate distance (dragging paper method),
using a brim or so-called mouse ears in your design,
increased the heated bed temperature, or
use of an adhesive like hair spray or glue stick (not any type will work) or specific sprays that are created for this purpose (e.g. 3DLAC, Dimafix, etc.)

Some people used tape on the build plate for adhesion, but I'm not a fan of tape. Not all tapes work. Tape needs to be applied correctly, prepared (sanded), etc. This is much more cumbersome than applying a little spray over the build plate. It can be successfully used on PEI, Buildtak (clones), glass and on the bare aluminium bed.


Problems with STL model in Ultimaker Cura

3D printers cannot print in the air without a prior layer or a support structure supporting the new printed layer. For the picture showing the bottom of the fruit, the red area is the calculated area that requires support for printing, so please enable that in the slicer application.
For the top picture please post a detail or a zoomed in part. It is currently difficult to see what is the matter. It looks as though the STL model is incorrect and Ultimaker Cura thinks that the seeds are upside down, hence the red coloring also. This means that you need to fix the normals of the faces in the STL model. Please look into this answer and this answer for some hints.


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

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


How to map Cura printspace to Prusa I3 printspace

Well, in my particular case, it helps to have the X and Y control (motor and endstop switch) plugged in to the correct ports :-( .  That took care of the X vs. Y orientation problem.

If you command "Home All" either via the LCD panel or over USB, the nozzle should sit in the front left corner of the bed as you face the machine ("stage right" for you thespians).
The link Chris T provided, ultimaker, provides helpful background information as well.

Next, if there are small offsets, find control can be set with a script similar to the following (leave out the auto-levelling command if you don't have that),
from printerbot talk forum .

M104 S{print_temperature}
G21 ;metric values
G90 ;absolute positioning
M82 ;set extruder to absolute mode
M107 ;start with the fan off
G28 X0 Y0 ;move X/Y to min endstops
G28 Z0 ;move Z to min endstops
M109 S{print_temperature} ;wait on temperature line
G29 ; Auto bed levelling
;G28 X0 Y0 ;move X/Y to min endstops
G92 X132.4 Y20; Reset actual position after G29 bug
G92 E0 ;zero the extruded length
G1 F{travel_speed}

And finally, there's a calibration file at thingiverse which prints large squares so you can see the exact offset.  I hope to get that file modded with a couple markers (indents, e.g.) to verify orientation as well as location.


Do stepper motors require any maintenance?

The stepper motor itself does not.  You may want to inspect the motors for debris or dust.

Depending on your configuration you may want to check on parts of your printer that connect to your stepper motor such as shaft couplings, pulleys, lead screws/threaded rods and belts.  The stepper motor wires should occasionally be inspected for wear and strain.


Getting rid of hardware parts smell (GT2 timing belt)

It's a garbage-quality belt, and it will probably continue outgassing at a steadily-decreasing rate for a very long time.

The fact that it has a strong chemical smell is pretty good evidence that it would not comply with regulations in civilized countries (such as REACH). I would recommend returning it or throwing it away and buying from a more reputable vendor. A large fraction of all cheap 3d printer parts these days are ridiculously far out of compliance with US/EU regs and basic common sense for contamination.

If you're hell-bent on using a crappy knock-off belt to save a few bucks, you could put it under vacuum to try to suck out the residual chemical gas faster. Just apply the vacuum very slowly / in stages (say over 10 minutes) so you don't get decompression blisters in the rubber. You shouldn't need a hard vacuum, dropping to 0.5-1 psia or 0.05 bar absolute for a day or two should help significantly. No guarantees though.


Effect of particulates on the viscosity of paste that is used to transport it in extrusion printing

I found a journal article "Experimental study of the viscosity of suspensions"
that looks like what you are looking for.  Just like most journals, it costs to access it. Also, it might be available as Open Access; but, I was not able to figure out how.


Steps per mm of extruder are incorrect after rebuilding

Ok, thanks everyone for at least taking time to read or thinking about this.

The Problem is an absolute mess and there are two possible reasons:

-> the octoprint eeprom editor is broken

-> the ATMega2560's eeprom is broken. as far as i know companies buy used atmegas to cheapen the price and the >100k writes on my chip has been reached

I will try to figure out the exact problem, if i find time in the next days.
My current setup is just deactivate eeprom and i'm good to go. Even wiping eeprom with a small arduino sketch will get the error to return.

Now i will be able to sleep again :D


First layer of print comes out poorly even when placed on a raft (which prints fine)

Turns out it had to do with the nature of the small holes that I was printing. I had to slow the speed of the initial layer down from 25mm/s to 15mm/s and also set Cura to 'optimize wall printing order' so that it didn't jump back and forth between holes constantly.

I also sped up the travel speed to 50mm/s on the initial layer to minimize oozing (although I'm not sure this actually did anything). Print came out beautifully.

Didn't even need the raft.


It sounds like your z-stop isn't engaging when it's supposed to. The z-axis end stop should be located at the left of the build plate on the z-axis column. When the gantry (with the printhead) comes down, it should contact that. If it doesn't contact it, or if the end stop isn't functioning (isn't sending the signal to stop), the z-axis will just continue to try and go down. Check to ensure it touches where  you want it to touch, and if it is, then check the operation of the end stop. You can do that with a multimeter set to ohms. Just detach the wiring from the main board, place your two multimeter leads on either wire end, then click the end stop. it should go from no continuity to full continuity when you hear the end stop click.

EDIT: The endstop should look something like this:


Can 3D printer work with enamel paints (or paints generally)? Are such printers available?

So, there's not really anything like a 3D painting machine/robot like I think you're looking for, but there are printers that do fine detail with actual paint, usually oils, but not on 3D materials.
I found a thread that talks about canvas printing about 8 years ago, along with a couple of videos that show current machines doing just that, but that's still not what I think you're looking for.
There are also CNC machines that print with enamel paints, but these are usually for 2D again, and not very precise, as they are used for lapel pins that have cavities to hole the paint while it dries. I'm sure something like this could be used without the cavities, but you'd have to do a lot of testing to make sure the paint stays put or mixes as you want it.
Just like the oil printers, these enamel printers are likely very large and costly.
Alternatively
What might work for you is hydrodipping. There's a variety of methods to this, but one company has done a bunch of research on this and can do extremely accurate detail printing to "paint" 3D objects. The below video shows a variety of these hydrodipping techniques, but I've skipped to the most relevant part.

Here's the original video of what I think you're most interested in. It's not 3D printing in the way most of us think, but it's definitely a fantastic outcome.

To explain, if these videos are ever deleted: detailed prints are made of a 3D model to color it exactly the way it needs to be, sometimes using multiple steps and computer positioning to get the object colored/"painted" correctly and seamlessly. One part of the video shows how the software can accurately make straight lines on a human-contoured face mask, while another part shows how a blank, fully 3D cat model can have spots or stripes added in 3 steps with the seams being completely invisible as well as it detailed enough to be mistaken for a real housecat beyond first glance.
As it turns out, you can do (some of) this yourself. After doing some research, I've found that you can actually get blank (instead of pre-printed) films and use an off the shelf printer, as long as it meets certain requirements. (I'm not recommending a site, brand, or anything else, this is just the first/only option I can find. If you do more research, I'm sure there's more options out there.)
https://www.tsautop.com/blank-hydrographic-film/
https://www.tsautop.com/blank-hydrographic-water-transfer-printing-inkjet-printer-6-color-inks/


I have not used or seen a solidoodle 4, but as found on the internet, the controller board used in the printer is a version of the Sanguinololu, and the reprap wiki says that

  The board is designed to be flexible in its power source, working with
  a 12V/5V ATX power supply or any 7V-35V power source via the on-board
  voltage regulator.

if you're using a board not older than V0.7 http://reprap.org/wiki/Sanguinololu

However, I have also found images that show the Solidoodle with this board:
http://www.reprap.org/wiki/SAV_MKI
which can be used with 11-15V. This however might be for older versions of the printer.

There are some things to keep in mind: if there is no voltage regulator on the board, make sure that all parts can take the voltage without overheating at some points.


After sitting for a week first layer won't adhere

If your having first layer adhesion issues:
Please try one (or more) of the following (Start with #1), and remember that all of them are equally important!

Make sure your bed is level (Maybe use a leaving stick (or whatever those bubble things are called))

Be sure the bed is clean (I recommend glass cleaner 1-3 squirts and then a light scrub of a paper towel)

Change the temperature of your heated bed (50 - 60 °C)

Check your nozzle height (.15 - .25 mm is what I use)

Lastly, use bed adhesion. Start with painter's tape (least damaging, easy to remove), then use a glue stick or even hair spray if necessary.


I would say it's not the best approach.

In the situation you've described I would rather install some kind of vertical ring a bit above your printer. This ring would organize your filament going from any direction.

So let's assume you got one spool on the right and one on the left of your printer, both are 1m away from the printer itself. If you get filament and put throught the ring then to your extruder.

In my opinion the ring should be around 15..20cm over the printer, it should have around 10..15cm diameter and spools should not be too low.

The only issue I see is unwinding spools which are too far from the printer because then filament would be unwinded angular but the same issue would be with and without teflon tube.

[edit]
Here is a simple change of your design

[edit2]
Please also note that you can assure proper angle of unwinding filament by installing small rings ("eyes") next to spools. These eyes will direct filament out of spool and then filament will turn to your big ring mounted on the printer. This is common solution in textile industry


Is Arduino Due a worth buy as controller electronics for deltabots?

An 8bit Atmega can provide bare-bones delta performance with Marlin (eg 40mm/s print speed) or pretty good performance with Repetier (due to more optimized algorithms). For a small and simple delta like a bare-bones Mini Kossel, 8bit may be fine. If you want to do high-speed printing or use any of the fancier features, you should go with 32bit.

The big issue with 8bit comes up when you want to do something that taxes the MCU. Delta kinematics already add a lot of extra math on top of all the normal printer functions like command parsing, motion planning, and heater control. For example, adding any of these to an 8bit Delta can cause issues:

Bed tilt compensation "auto-leveling" -- the coordinate space rotation transform adds a lot of extra floating point calculations to every movement segment. That really taxes the 8bit Atmega since it does not have native floating point support. (Note that pre-print auto-calibration such as in the RichCattell Marlin fork is not the same as bed tilt compensation and does not add any run-time processor load.)
Full graphics LCDs -- refreshing the LCD screen for animations and status reports takes a surprising amount of horsepower. 8bit Marlin is widely known to suffer from stuttering and print quality issues when running a GLCD on a delta.
Highly faceted (smooth) curves, particularly over USB -- the high rate of gcode command processing sucks up a lot of clock cycles, particularly in firmwares that run USB comms as a top-priority interrupt.

What the Due (or other 32bit board option) does for you is de-bottleneck the MCU so you can push the printer harder or utilize features that add processor load. Here's why they're so much better:

In simple clock speed terms, the SAM3X8E in the Due/Duet/Alligator/etc is about 5 times faster than the Atmega 2560, and the LPC1769 in the Smoothieboard/MKS-SBASE/etc is about 7 times faster. But they're actually MUCH higher performance than clock speed alone would suggest, because the 32bit architecture and native floating point support mean far fewer clock cycles are required for complex calculations.
They also have more RAM, meaning the the firmware can manage more features and look farther ahead when motion planning.
They also have more program space, meaning the firmware can, if desired, be compiled as a single full-featured build that covers all possible printers (as RepRapFirmware and Smoothieware do) and thus end-users don't have to edit and compile code in the Arduino IDE to configure the firmware. The Atmega line requires hundreds of conditional compile statements in the firmware to exclude unused features from the binary to get the memory footprint down.

All that said, the switch from an 8bit Atmega AVR to a 32bit ARM Cortex-M3 is still just an upgrade from a late-1990s processor to an early-2000s processor. Neither is "modern" by any stretch. (For example, the BeagleBone Black used by Redeem and MachineKit utterly blows away the Due in processing power and memory. But those options have steep learning curves at the moment.) The Due can still be bogged down by printing very fast with lots of features enabled. It's a big upgrade on an Atmega, but I predict it's going to be replaced by much faster controllers within the next few years. Announcements of upcoming next-gen controller boards are already trickling out.

To summarize, the answer is yes, a Due-type board is a good buy if you want a high-performance printer. It will meet 99%+ of user's needs today. But it will be replaced in a few years, just like the Atmegas are being replaced now.

As for specific Due shields, I strongly recommend NOT going with RAMPS-FD. It was cloned for sale by Asian companies before the design was finished, which seemingly caused the original designer to abandon it before working out all the bugs. RAMPS-FDv1 has some nasty design flaws such as heaters turning on while flashing firmware. RAMPS-FDv2 is better, but can experience unreliable and oddball behavior due to unresolved issues in the circuits intended to make it compatible with both 3v3 boards like the Due and 5v boards like the Mega. (For example, the thermistor voltage reference circuit needs modifying to work right, and there appears to be timing issues in the 3v3-5v level shifters.)

RADDS is a good Due shield. It is a simpler, more reliable, more compact version of RAMPS-FD. It is very popular in Germany and has recently (late 2015) become available for sale in the US.

I also recommend purchasing the Due R3-E instead of the regular Due R3. Anecdotally, the "E" version appears to eliminate some firmware bootup issues that can occur when the board is first powered at lower than nominal voltage.

One possible downside to the Due is that Arduino just announced they are no longer manufacturing it. So all new Due boards from here on will be made by 3rd parties. That's not necessarily bad, since it's open source and many other companies will surely continue making them, but there won't be any more made by Arduino.

For single-board options using the same SAM3X8E processor as the Due, the Duet 0.8.5 is becoming quite popular. (It runs RepRapFirmware, which has some great Delta features.) The Alligator runs Repetier. There are several other beta/experimental/development boards in the works too. The community appears to be moving towards the Due and Due-compatible boards over the other various options.


Are self intersecting meshes dirty from a 3D printing perspective?

Self intersecting meshes are considered dirty, yes. The reason you haven't had trouble before is probably that the software you were using was cleaning your mesh for you, behind the scenes.
Generally speaking, these meshes can be cleaned without too much trouble by software like netfabb (https://www.netfabb.com/) which has a nice free version that I use for basic cleaning of some of my meshes. A quick google on "netfabb free fix mesh" should turn up a tutorial or two.

If you're interested in learning more about an operation you can use to make this a single unified mesh, it's called a Boolean Union, and the blender project has a nice (open source, I think?) implementation of such: (https://www.blender.org/manual/modeling/modifiers/generate/booleans.html)


3D printer stepper motors only going one direction and skipping in the other

From an electrical standpoint, a two-phase stepper motors (what most 3D printers use) works the same backwards and forwards, the phase just reverses.  If you are stalling on only one direction, I would look to see if you have a mechanical bind in that direction.  Generally a wiring issue will cause the motor to either not run at all or to run in the wrong direction.

A few things you can check:

Decouple the motors from their mechanical load and confirm that they all run correctly when they aren't driving a load.  If you can't do that, disconnect them all then connect a spare motor to each cable one-at-a-time.
Turn each of the axis with your hand and make sure it turns smoothly throughout the entire range in both directions.  Note: Some times a binding issue is acceleration related - a loose frame or coupling can cause this.
Monitor the supply voltage to make sure that one of the motors is not pulling the supply down causing all the others to stall.


The most common choice for insulating thermistors is glass fiber sleeving. It tolerates very high temperatures, and is commonly rated for up to 600 °C.

Teflon is also used but has a rather low upper limit on its working temperature; it shouldn't be used at temperatures exceeding 260 °C - which rules it out for your purpose.


How can I stop my print bed tape from sticking to the filament?

This can highly depend on the slicer you are using. Some software such as Makerware and Slic3r allow you to adjust the settings for the first raft/part layers. I might suggest adjusting this "Z0" point to about 1/4-1/2 of your layer height. Essentially the first layer (or two) will not adhere as well.

This is just one suggestion of many solutions. Here are some other variables I could think of off-hand:

Type of build plate tape (ie masking, painters, kapton, etc.)
Type of material. I've noticed that PLA is very stubborn if you let the part completely cool after printing and that it's much easier to remove the part from the build plate/raft right after it's complete.
Type of build plate. Are you applying too much heat (if you have a heated bp) for the material such as PLA?
Try lowering your layer height. This will ensure that each strand does not have too much surface area and therefore less chance that it will create a vacuum affect with the build plate. This can, however, result in a worse surface finish.


Rectangular pattern constraint is lost when applying a fillet to the sketch object

In some CAD packages, this is exactly what I would expect.  Models are constructed by applying operations in a specific order.  The fillet is a separate operation, and is not part of the base rectangle.

The base rectangle is defined.
You pattern the base rectangle.
You define a fillet using the base rectangle as the reference.  The fillet affects only that one rectangle.

OTOH, when you modify the base rectangle all are changed because the base rectangle is defined before the patterning operation.

If you can apply the fillet before the patterning, it may work as you wish.


a good way to convert a 3D print file like STL to STEP a useable file format for plastic injection molding companies

I don't know much about plastic injection molding companies, but I do manipulate a lot STEP, STL files and I do know that it is possible to achieve "a good way to convert […] STL to STEP file format […]". For the record, the manufacturing process isn't recorded within these files format (at least not yet) so you don't have to specify the final use.

However, this is a delicate process which isn't easy for beginners in CAD engineering.

As said before, the STL files is a tessellation of a surface with triangles, while STEP defines precisely the surface with curves. It's basically the difference between raster graphics and vector graphics: most fully automatic reconversions programs (such as Inkscape in case of images), would create something quite approximate to the real shape. Manual programs would require time and knowledge of the needed tools (Inkscape can do it too, in case of images).

For the record, asking for a STEP file to be a STL file is as easy as transforming a vector graphic to a raster graphic, it's a one-click transformation. What you are asking, the reversed, is complicated.

What will be done if you import a STL file to a standard CAD program, it will consider each triangle as a defined unique surface, and in most cases, the standard CAD program will have a lot of difficulties to handle the STL. It could then export it to a STEP file, but this will make a huge, incredibly heavy file difficult to handle (I've seen STEP files over 300 MB while the STL was less than 10 MB).

The good way to do so, is to go through a reverse engineering program that handles better these troubles. I don't know any being free, and they all require extensive experience, expansive licenses and a bunch of time generally. For instance, I know that Catia, SpaceClaim or 3-Matic are programs that work very well for your issue, but they are both very far from affordable or easy to handle if you aren't a CAD designer.

Another bad way would be to pass through a 100% automatic reconstruction/conversion to STEP, but it would make something not exactly accurate to the original part, and may not be of any use depending of your application.

My best advice for this would be to find someone or some enterprise that can practice the good way from your STL to have the STEP file you want. You should also very much specify for what use your file is, because as a design engineer I wouldn't generate the same STEP file depending of the use of each surface.

I hope this answer isn't too much a disappointment for you, I know it won't solve your problem but it can help you understand why it is such a hard problem.


How fast can printer head move without damaging steppers?

Short answer no

We use stepper drivers to limit the current, the travel speed is at capped by the amount of current supplied by the stepper drivers. This prevents the stepper motors from damaging themselves. You can set 200mm/s in the slicer, but you have no guarantee that that will be reached in real life.

One thing to keep in mind though is that setting your travel speed too high can induce artifacts such: shifted layers, ghosting, uneven extrusion, etc. So the best thing is to keep the speeds within the specified limits.


The described behaviour could happen if, e.g. X_STEP_PIN, X_DIR_PIN and X_ENABLE_PIN are not correctly mapped.
I guess you will find them in pins_RAMPS_144.h. Make sure the correct file is used.


Poor adhesion only for first couple of inches

I'd recommend using the "skirt" function if you're not already.

The idea is to print a few perimeter layers around where your part will be, but not actually touching your part.

Most slicers support this and you can choose how much skirt you want to print.  This addresses the issue you mention, and it purges old filament that has spent too much time in the nozzle.  As an added bonus, it gives you a good indication that your print location, print height, and first layer adhesion are all good.


How to print a two color part with only one extruder

What you ask may be easier than you think. The slicing software is unimportant, generally speaking. Consider especially that your requirements fit the solution spot on.

Take a look at this thingiverse snowman.

Each of the colors is a separate model. Each of the colors is only one layer thick (0.200 mm). Each of the colors is placed with zero overlap to the adjacent colors, as the extrusion multiplier will allow enough "squish" to cause a bond to its neighbor.

You would create a model with the necessary shape for your lettering and insert the appropriate color for them. Print that model but leave it on the bed. If the bed is heated, all the better, but don't let it cool to the point of release. If it's not heated, the adhesive should hold it until project completion.

For the main background color, your model would be normal but with a single layer subtracted at the base. The subtraction would have to be the shape of the lettering. Consider that you're creating indented or recessed lettering. Use appropriate modeling techniques to perform this action.

Keep in mind that you'll want the lettering to be mirrored, as you're printing it "upside down" on the build plate.

Swap out the filament to the main color and print.

You are color limited only by your determination and patience, as you have to swap out filament and also have to create appropriate models with recesses to take the first layer, of which you'll also have to create models.

I've created at least one of the snowman pictured and it came out quite good. The layman will not be as astonished as someone familiar with 3D modeling and printing, however. You get a better appreciation when you know what goes into the project to get this result.

EDIT to add more info, rather than fill the comments:

The above method works only because the inlay is a single layer deep. If your slicer supports changing layer thickness during a print, you could print the first layer at the max for your nozzle, say 0.3 mm then set layer 2 and upwards to the resolution you desire for the majority of your print. I use Simplify3D which supports such actions. I'm not sure of the others.

Relevant to the questions posed in the comments, your modeling software may be a factor in this process. The modeling software will create/assign a pivot point or some other name to a location of reference in the model. The slicer will use that to position the model on the bed.

Here's a concept I would use to perform this task. Start with your single layer lettering, ensuring that the thickness of the letters will match your first layer height. Save the model as an STL file. Leave the lettering on the screen in your modeling software.

Create or import the case file. Position it as you wish relative to the letters. Of course, both models will be flat on the build plane or all bets are off. Use the lettering in a boolean subtraction to remove the shapes from the phone case model.

If the above does not remove the lettering model, delete that and you have the recess. Save this model in STL.

When you load the models in the slicer, they should drop into the same location relative to each other.

When you print the letters, they will be on layer one. When you print the remaining model, the cut-out portion will be on layer one, while the rest is placed atop the two color portion. The print head will move up one layer to adjust for the extra depth.

If you require the letters to be thicker than a single layer, one of the options you have is also in your question. Create the letters in the thickness you wish, use them to create the recess in the case and print separately. In so doing, you will be counting on the printer's ability to make clean bridges. The letters may fit cleanly, may have some play or slop, or be too large to fit easily. It would behoove you to make a test piece or two, perhaps a simple slab with one or two letters to see how that concept works in the real world. I was pleasantly surprised to see how well the public library's genuine Prusa i3 MK2S performed a challenging bridging operation.

I apologize for overlooking the reference to first project. With that in mind, I would consider that this is a slightly advanced project. Your modeling software and modeling software skills will obviously come into play here and is a separate subject/question/topic for discussion.


When you have a disaster print like this you almost always get carbon in the hot end. I have micro hand drills (0.2 mm) that I carefully use on the tip of the nozzle. There are also atomic pulls where you add plastic, heat it up till it extrudes then let it cool. Once cooled to 70°C pull hard. Repeat until pulls show no black. Or, if your nozzles are cheap just replace them.

Note next time this happens, turn the hot end on so you can remove it quickly. Sounds like you chipped away.


Stepper motors are not working when connected with RAMPS 1.4

I actually thought the problem is in the electronic circuit but the problem is the baud rate. I initially took the baud rate as 115200 but later. after someone's suggestion, I changed it to 250000 and now it's fine.


Z axis top brackets, of P3Steel, differ between v1.x/2.x and v4

I've just seen this right now, I'm Alvaro Rey, the designer of the p3steel v4 mod. The change was made, because with previous versions with the extruder homed, if you go up in the Z axis, the extruder motor could hit the Z axis top plate. So, in order to avoid that, I just changed the design.

The bearing in the z axis is not necessary but some people prefer to use it, in order to avoid wobble in the threaded rod.

Anyways, I designed a printer part to fix the bearing in the Z top plate.


Can MeshMixer export models for color 3D printing?

Color is only displayed if you set MeshMixer to render VertexColor:

MM menue/View/MeshColorMode/VertexColor

Color should be visible if VertexColor is active.

Meshmixer is a sculpting program, so it isn’t made for taking exact
measurements, creating mechanical parts, or creating architecture
models.
Basic rendering options make pretty screenshots, but advanced users
might want to add in backgrounds or set up custom lighting.

Also, you can read more about this matter on this link.


FDM printer first layer infill swell upward

Had tried below and didn't work:

Clean the bed
Use a brand new glue stick
Verify delta configuration and make sure z-plane is flat and parallel to bed
Adjust z height to minimize the distance between nozzle and bed when z=0
Increase first layer extrude width

Printed again and watched carefully, then found that it was pull up because the printed PLA slice shrank. I realized that the problem was related to my change on the fan duct. Before, the fan blowed directly to the tip of nozzle; after changed it blows around.

Tried to turn off the fan on first layer, the problem was solved.

I suspect that the fan duct change made the extruded material not cooling down immediately. It shrank when the air blew on it. I need further test to verify it.


How to center my prints on the build platform? (Re-calibrate homing offset)

When centered in the slicer correctly, without offsets defined in the slicer, the printer is most probably incorrectly configured! Luckily you can do something about that! Basically, you will have to calibrate the printer for a new center.
Printer origin?
First of all, the firmware determines where your origin of the printer is. This implies that you need to properly set bed dimensions and offset values from the end stop switches in the firmware (usually not necessary out-of-the-box, but important when a newer or different firmware version is uploaded). These offsets determine where the origin of the bed plate is located. For Marlin firmware it is very common (for most printers) to have the origin specified at the front left corner (when facing the printer). From the configuration of Marlin we find the origin is e.g. in the front-left corner. Note that this can be rotated 180 degrees in certain printers, so the aft-right. Also be aware that there are a few printers that have the origin in the center, e.g. Delta's and a few Cartesian printers. Marlin definition (edited snippet) of a common bed layout:

 *      +-- BACK ---+
 *      |           |
 *    L |    (+)    | R
 *    E |           | I
 *    F | (-) N (+) | G
 *    T |           | H
 *      |    (-)    | T
 *      |           |
 *      O-- FRONT --+
 *    (0,0)
 * .(-Xh, -Yh)

How do I find the physical origin of the printer?
This can be tested by instructing the head/nozzle to go to e.g. (0, 0, 15) using a terminal/console or a simple G-code file with a move to that coordinate that you print from SD card (e.g. G1 X0 Y0 Z15 F500); note a Z of 15 is chosen for safety!. When this is performed, the nozzle should be at the (elevated, so X, Y) origin as defined by your firmware. Usually this is at the left front corner of your build plate (there may be clips there, so therefore the elevated value), but this may be different depending on the firmware settings or firmware brand.
Next step is to configure the slicer as such that this coincides with the actual origin. Incorrect slicer settings can cause the slicer to assume the origin is at a different position than your actual position. In Ultimaker Cura, the "Origin at center" is notoriously known for this when the physical origin is not in the center, but in a corner. When the slicer is properly instructed, but the origin is still not at the corner of the build plate (beware! in some printers the origin is in the middle of the plate) you might have incorrect endstop to origin offsets.
Determine the offset first!
To quantify the offset of the center as it is known by the printer software (firmware) it is advised to print a large square that is a few percentage smaller than the maximum size of the bed. E.g. you can create a square hull at e.g. 90 % of the dimensions of the bed (parametric designs are very useful for this purpose, see e.g. this design). There are many things (.stl models) to be found on the internet. If it includes a cross, even better as some platforms have a mark in the center of the bed.
Example of a bed center calibration model

Once printed, measure the distance from every edge from the build platform to the printed square. If you fail to print the square, please check the level of the platform; this is also an excellent test for the level of your bed!
The measurements should give you a notion of the offset of the bed. E.g. for the X-axis you measure a distance of 12 mm on the left and 8 mm on the right (when facing the printer) you can easily deduce that the center is (12 - 8)/2 = 2 mm to the right (positive X direction). This implies that the printer manufacturer has done a lousy job by delivering you a printer with an offset bed; better said incorrectly configured in their firmware. Note this is not uncommon!
How to fix this!
Once you quantified the offset, you want to be sure that your next print prints in the middle of the bed. How to proceed? Basically there are a couple of solutions you can use, each with its own advantages and disadvantages.

A simple solution (i.e. if the printer support this) is to adjust the position of the endstops. Alternatively you can print alternate endstop holders to match the position change as measured from the calibration print.

Another simple and popular solution is applying an offset in the slicer. You could do that in the printer options some of the available slicers. If such options are not available, you could add G-code commands in the start code to create the offset (e.g. G1 X-2 moves to the left and G92 X0 resets the X origin). Note that this is a quick fix and should be applied wisely. The printer does not know where the actual center is! You merely changed if after the homing sequence. Exchanging .gcode with fellow enthusiasts with the same printer may have adverse effects.

A far better solution is to fix the center in the firmware so that the printer knows the actual center. This requires some extra effort by uploading firmware (files including configuration settings) to the printer or send G-code commands. The latter option will be discussed first.

A prerequisite of this method is that it requires the G-code command [M206](https://reprap.org/wiki/G-code#M206:_Offset_axes) to be supported by your firmware; note that not all 3D printer firmware solutions are able to use this G-code command for axes offset definition. E.g. the stock Anet A8 runs a modified Repetier version that does not support M206, it would be time to upload a new firmware like e.g. Marlin Firmware making this particular printer safer as the stock firmware does not include thermal runaway protection! See question: "What is Thermal Runaway Protection?". To send G-code commands to a printer you have the option to hook up your computer to the printer over USB and use a 3D printer program that support sending commands to the printer (this is called a terminal; i.e. an interface to the printer). Programs like PronterFace, Repetier-Host, OctoPrint, and probably many more have such an interface. A simple alternative that works also is creating a text file (with .gcode extension) with the commands on separate lines and executing the "print". The following codes need to be sent: M206 e.g. M206 X-2 Y2 (move center left and to the back, note to use integer values, float values are not allowed!) and store this new center with M500.

The final, best solution is to set it fixed in the firmware. This requires an upload of a more recent configured version of an applicable firmware. See e.g. question: "How to upload firmware to reprap printer?". Note that there are different methods to upload a firmware to the board, it is best to search the internet for the applicable method for your board.

To do that you will have to be comfortable with computer software and tools to build source files and upload binary code to the printer. This depends on the type of firmware you choose and therefore cannot be described for each firmware in detail. Various sources on the internet describe this process. Generally speaking, it requires you to set the bed and offset values/positions correctly. For Marlin Firmware this comes down to changing the settings in the configuration file, this is similar in other firmware software solutions:

// The size of the print bed
#define X_BED_SIZE 220
#define Y_BED_SIZE 220

// Travel limits (mm) after homing, corresponding to endstop positions.
#define X_MIN_POS -35 ; used to be -33, so 2 mm shift to left now
#define Y_MIN_POS -8 ; used to be -10, so 2 mm shift to the back
#define Z_MIN_POS 0
#define X_MAX_POS X_BED_SIZE
#define Y_MAX_POS Y_BED_SIZE
#define Z_MAX_POS 240


Anet A6 assembly problem - remaining power cables don't match instructions

The manual appears to be available here, Installation Instruction_Anet A6 3D Printer - Elektor
However, according to this comment from Hard copy of the build guide?, there is a mistake in the PDF of the manual, with respect to the heatbed, and as such, it is better to follow the videos:

I find it is better to use the 3 videos:

3D Printer Instruction--Anet 3D Printer A6 Assembly Video 1
3D Printer Instruction--Anet 3D Printer A6 Assembly Video 2
Printer Instruction- A6 - Hot Bed Level Adjustment and Print Test

Only errors in the videos and i believe the instuction the Hetbed
fixing plate i have build diffrently , rotated by 180 degrees
vertical, since it is better for the belt and somewhere in the video
during fixating of the end-switch and the blower he interchanged the
screws.

However, looking at the manual, if it is to be believed, then be aware that as well as one connection for the extruder motor, there are two connectors each for both the extruder and the hotbed heaters:

One for the separate heating elements, of the extruder and hotbed respectively, and;
One for the thermistor sensor (both the extruder and the hotbed have separate thermistors).

This makes five in total for the extruder and the hotbed combined.

However, the power connections for the Extruder motor has four pins (in white at the top), whereas the heating elements for the hotbed and the extruder have two pins and are of a different shape (in green on the left). The sensor connections for both the extruder and the sensor have three pins (in white at the bottom), but it should be easy not to confuse them, so long as you follow the wires to check to which component they go to.

Additional points to be aware of
From this comment in the same thread:

I just built an A6 three weeks ago and with the videos it is really a
breeze to assemble the unit.
Just pay attention to the heat bed mounting plate as it is installed
bottoms up in the video. The bar connecting the outer two plates where
the heat bed is finally mounted should be below the plates, not above
as in the video.
Also, if you still have time, order some decent toothed belt, Igus
Drylin RJ4JP-01, and toothwheels for the Y and X belts and replace the
original pulleys, bearings, and belts before you even assemble the
unit. I just changed mine last week and it does make a hell of a
difference - with this little upgrades (cost me less than 30$ for
everything - at Amazon) you upgrade from an okay printer to a really
decent machine.

The belt: https://www.amazon.com/Anycubic-Meters-Timing-Pulleys-Printer/dp/B0152ZNDLK
The pulleys: https://www.amazon.com/Aluminum-Bearing-Timing-3D-printers/dp/B0188HW4Z0
The bearings: https://www.amazon.com/Printer-Solid-Polymer-LM8UU-Bearing/dp/B06XPRCMJS
(actually, you need 8 pieces - not seven as in the images - 4 for the
Y-axis and 4 for the X-axis)

The above are not the actual articles I've bought because I am from
Europe where Amazon sells in different quantities.
If you want to go on the safe side, grab a second power supply and two
MOSFET boards to remove the high current from the mainboard:

PSU: https://www.amazon.com/eTopxizu-Universal-Regulated-Switching-Computer/dp/B00D7CWSCG
(just as an example)
MOSFET: https://www.amazon.com/Wangdd22-Printer-Expansion-Heatbed-Current/dp/B01MY50JL3
Power socket and switch: https://www.amazon.com/URBEST-Module-Switch-Certification-Socket/dp/B00ME5YAPK

Last recommendation: get some 3mm borosilicate glass to lay (clip)
over the heatbed. This will make the prints stick better and also
provide a perfectly flat surface for the builds (still, you'll need to
do the levelling)
Glass:
https://www.amazon.com/Signstek-Printer-Tempered-Borosilicate-2132003mm/dp/B00QQ5Q3BI
When assembling the heatbed mount, pay lots of attention to the 16
screws. Tighten them one by one diagonally and move the bed around. If
the bed feels stuck, loosen the last screws and shift the mounts
around a bit. The lighter this mount moves, the better your prints
will be.
One thing that you must be aware: This printer is a great little unit,
but it needs love, dedication and plenty upgrades. Out of the box it
works okay, but with the upgrades it becomes a really good unit.


What the adjective "downstream" is used for?

Without more anymore context "downstream" could be in reference to a print that would be sent to another machine for post-processing. The post-processing machine is "downstream" from the machine used to make the print in the first place.


What is the "Detailed format classification" of the ISO 6983 (G-Code spec)

This is simply the formalised definition of the syntax, so that a parser can be written to interpret any legal G-code. Without this, there is ambiguity - not in the general operation, but in the bounds of what is 'legal' and what should be rejected.

Taking the example X+053, this is not a position of 53 units, it is:

Address X
Sign is required (in this implementation)
Leading zeros can be ommitted
Up to 5 orders of magnitude before the decimal
Up to 3 digits of precision after the decimal

This means that X can range from +99999.999 to -99999.999 - an interpretation which matches the verbiage at the bottom of the page.

As hinted at in the text, it is possible to use various fixed precision number systems (think using integer milimetres rather than decimal metres), and also to anchor at the most significant bit, so 001 could represent 00100.000. It may help to remember that these specifications were designed in the days of dedicated hardware rather than general purpose computers, when the standard portable storage medium held ~600 kB, and relate to actual machines that had been developed long before that.


In the world of hobbyist milling machines, a DRO accessory is extremely valuable for improving work flow and accuracy of project builds. The Digital Read Out devices run the gamut from affordable to astonishingly expensive and cover one, two and three axis readouts.
For single axis purposes, some hobbyists will simply find a means to attach a digital caliper, as you've suggested, to the machine with appropriately fabricated brackets. That's one option. For a few dollars more, there are off-the-shelf digital read-outs, such as this one from Amazon:

Six, twelve and twenty-four inch travel options are available with the pictured six inch unit priced at US$39.95, a reasonable figure for 0.01 mm accuracy.
One can purchase pricier models with higher resolution if required.
Brackets included with the device may not fit well to your application and may require modification.
Some DRO devices, such as the one installed on my mini-mill, use physical contact (gears) to read the position information, which means friction and loading of your printer. Other models use micro-engraved glass scales and have minimal friction, but will likely be a bit more expensive.


Unfortunately, you may have to destroy this part, or the build surface, just to get it off the plate. It looks really on there, and if you can't get under it even with a razor that further supports my gut instinct. It's happened to me before, just part of learning how to print with a particular material on a particular printer and build surface.

One thing to try before just hacking away at the part or replacing the build surface (which you may have to do anyway) would be to heat the plate back up to maybe 60-70*C, then hit the part with some freeze spray (or the poor man's version, turning a can of air duster upside-down). The rapid expansion-contraction may pop the part free. How effective this is depends on the plastic you used. PLA doesn't stretch and shrink much, but by the same token it's also very inflexible, so the stretching and shrinking it does do can stil pop the part off. This method's really effective for plastics like ABS that stretch/shrink a lot with heat. Remember to ventilate well; the principal component of these sprays is difluoroethane, which isn't great stuff to breathe in any significant concentration, and when spraying the liquid the resulting "steam" state of boiling liquid is much more flammable (so after the bed comes up to proper heat, I'd turn off the printer just in case).

EDIT: Per the comment to this answer, an alternate method would be to heat the plate even further, to about 80-90*C, which would heat the PLA beyond its glass transition temperature, softening it and reducing its adhesion. You would destroy the part, but parts can be reprinted, that's the beauty of owning a general-purpose computer-controlled additive plastic forming machine.

Your first layer including the brim looks a little close to the plate, which is part of the problem; you really squished that first layer down onto the bed. I would relevel the bed a bit further away, or (if you're happy with how actually level the bed is) set a Z-offset to increase first layer width. There's a very fine balance to be struck here; once you find it, printing (and removing said prints) becomes a lot easier.

In future, a build adhesive like Elmer's glue stick or hairspray (or a dedicated adhesive like 3DLAC or Bed Weld) also doubles as a release agent; the adhesive grabs the extruded plastic to keep it on the plate, but also prevents direct contact between two plastics and thus avoids any chemical bonding between the part and plate. Also consider upgrading to a flexible removable surface, like a magnetic BuildTak surface. Being able to take the bed off the printer and then flex the surface to help  pull a corner free (at which point you can slip a scraper in to lift the rest of it off) is a real boon to these types of situations.


Sketchup Free STL import in FreeCAD not working with Fasteners Workbench

Stls may not properly import as solids.  This is likely what is happening in your case.  Stl format is ultimately just a bunch of triangles without a proper definition of a solid.  The boolean Difference found faces to attach to the circle so it used them.  The trouble is, there were even more faces at the same location (not uncommon).

You could manually delete and repatch the triangles in Mesh Design or if the shape is simple enough (I think your box fits the bill), redraw it.  I don't know how far sketchup has come with file formats, but a different format may convey your solid better between software.

That said, in your shoes, I'd be making cylindrical and hexagonal cutouts and gluing a nut into my part.


Under extrusion towards the end of the print

Do anyone have any ideas? What this can be? How can I fix this?

At least judging from the pictures, that does seem like under-extrusion.  Some ideas for further investigating the issue.

The problem may be due to the gcode being wrong.  In this case, your printer is merely executing correctly... the wrong commands.  To check if this is the case:

The easiest, but inconclusive way, would be to re-slice a model that fails consistently, with a different slicer.  If the second print came out good, than you would know that the problem is with the slicer.  This method is inconclusive because you wouldn't not if the gcode is bad or if it simply happens that your printer cannot print well that specific sequence of commands (which may still be emitted by the other slicer under different conditions).
The more conclusive analysis would be to look at the gcode of a failed print where the fail happens between two geometrical identical layers.  This seem to be the case for the print in the picture, btw.  You should then compare the gcode of the layer that printed good with that of the layer that printed poorly.  If the gcode differs... then you positively know the slicer doesn't work as it should.

The problem may be due to a mechanical fault with the printer.  Here the only idea I have to offer is overheating of the steppers and/or their controllers.  This may in turn make the extruder servo skip some steps and therefore extrude less filament.  If you perform the conclusive test above, you will know if this is the case.

The problem may be due to a firmware bug.  This is difficult to investigate, my only suggestion would be: upgrade to the latest and greatest, if you haven't done it already.

The problem may be filament-related.  This could be a number of things, but since the problem seems to happen at towards the end of the print, and your are printing at relatively high temp, an idea could be that too much heat reaches the cold end of the extruder, interfering with its extrusion.  The easiest test here would simply be to re-print a failed print with a different filament.  In your case I would suggest some PLA, just to decrease the temperature and change the chemical composition too.

These are more or less all shots in the dark, but - together with asking here - it would be what I would do to debug, had I the same problem.  Keep up posted! :)


I wonder if this problem is unrelated to your material or printer, and purely a matter of slicer breakage. Have you tried printing gcode files you created before the problem appeared? If you use Cura and upgraded it, you might have hit one of the bugs where it assumes by default you have 2.85 mm filament, even though your printer actually uses 1.75 mm. That will create underextrusion that has the whole printed object coming apart like an unravelling mummy. When I've seen it happen, it looks very similar to your picture.


Underextrusion after travel moves with PETG/Colorfab XT

Have you tried adjusting the Extra Restart Distance in Simplify3D or Retraction Extra Prime in Ultimaker Cura?  Most slicers should have a similar setting, perhaps named just slightly differently.  A small positive value can help prime the nozzle after a long travel when you've lost back pressure or oozed a little.


How to transport a 3D printer? Dismount needed?

Yes, fix the motors and any other loose/movable parts. Remove the bowden tube if it's there, and any other parts that are sticking out. Put the whole thing in a a bag to protect from dust, and put the bag in a box to protect it from getting beat up. Remember to calibrate it when you're ready to set it up again.


When did mass produced FDM printers become available?

By 2016, very low price kit machines were available to hobbyists [..]
Was this the start of the break-out of cheap FDM machines

No, not by any means. The RepRap project started in 2005, and by 2008-2010 there were several open-source printer designs out there that were somewhat workable for hobbyists. These designs were still quite expensive, you needed to source all the components yourself and do a very significant amount of troubleshooting.
However, as early as mid-2009 you could buy a Makerbot Cupcake CNC for \$750 as a kit (which might have involved some soldering) or \$2500 fully assembled (presumably without soldering, but it's conceivable it was plug-and-play). Makerbot went on to become quite a successful company, piggybacking off the RepRap project and could be viewed as the "break-out" you ask about.
I purchased my first printer kit (no soldering or firmware involved) for \$500 (plus around \$150 in shipping and taxes) in February 2014; cheap hobbyist machines were commonplace well before that.


Loading TPU/TPE can be particularly challenging because many printer loading scripts run too fast for the soft flexible filament to effectively purge whatever normal filament you were using before. A couple tips:

Load with a slightly higher temp than either the TPU or previous filament require, so as to minimize the melt viscosity and reduce the force required.
Make a custom gcode file that contains a slower loading routine: wait for heat, then advance the extruder at a very slow rate for a long distance. Then you just "print" this gcode file whenever you need to load TPU.

However, simply being able to load is not necessarily enough. Not all extruders can reliably print flexible filaments, period. The larger the gap between the pinch wheel and inlet to the hot end, the more likely the filament is to buckle and come out the side. You need to make sure this gap is as short as possible. If there is more than a couple mm of gap, you'll need to make gap-filler or print yourself a new extruder designed for flexibles.

Printing slow and without major velocity changes can help, too. Use relatively low layer heights and low, constant feedrates so the extruder doesn't have to run fast or change pressure often.

Harder flexible filaments will be easier to print if your setup is borderline. Ninjaflex is one of the hardest to print because it is relatively soft. Semi-flex type filaments are much easier to print if your hardware isn't set up optimally.


Is there any better way to make this transparent dome?

The filament seems to lose its translucency past a certain thickness

That's exactly the point. Think of translucency as a percentage of light being allowed through, per amount of material. 2x the material means 1/2 the light. You need either less material (which becomes brittle as you saw), or a more translucent material. I think it has little to do with the model itself.

Also - check out OnShape. One of the features it has is a "shell" function, that does what you're describing - takes a single 3D feature and creates a shell out of it of consistent thickness.


Can Cura alert me (give a warning) if it estimates times for layers are too long?

Look at Cura's cooling settings. It doesn't have a warning like you asked for, but it does have options to control the fan to avoid over-cooling. I think you need to set "Regular/Maximum Fan Speed Threshold" to the number of seconds you want to consider a "long time" for a layer to take, then set "Regular Fan Speed" (for layers that take a long time) to 0 or something low, and "Maximum Fan Speed" to 100 or whatever you normally want to be using.


Anycubic i3 MEGA not heating past 140 ºC

I recently had similar problem with my Prusa i3 MK2.5. It was not able to maintain the set tempereature. I measured the heater catridge (which was new) and its resistance was correct (about 4 ohms). So I changed the hotend MOSFET on the stock board with no result. So I changed the heater catridge for the older one and the issue was gone.
Since you have changed the heater, it is unlikely that you have multiple bad ones. Thus the only thing that remains is the MOSFET and the power supply. Make sure your power supply is stable under load and can deliver enough current.
More likely it is the MOSFET. It behaves like a resistor in the path for the current. If it is swithced off, it is like a large resistor (units or tens of megaohms) in series therefore no or very little current can flow. If it is switched on (units or tens of milliohms) the resistance is very small allowing the current to flow through the heater. If a MOSFET is bad, when it is switched on it can have higher resistance (units of ohms) and thus limiting the current and creating a voltage divider. Which you can measure.
You have to get to the bare wires that lead to the heater. Turn on the heater. Place your voltmeter lead on one wire and the other lead on the otehr wire. The voltemeter should show voltage close to your power supply voltage. If it is showing less, the MOSFET is bad and needs replacing.
For that you will need soldering tools and skills. You probably have an SMD MOSFET soldered directly to the board. I suggest removing it and replacing it with a THT MOSFET that you would place separately from the board with its own heatsink. When on the board, the board acts as a heatsink.
If you cannot do that yourself, ask someone to do it for you.
Before replacing the MOSFET, find whether it is a n-channel or p-channel MOSFET. It will most likely be an n-channel MOSFET but make sure it is.
If you replace it with THT MOSFET I would suggest these two: IRFZ44N (n-channel) or IRF4905 (p-channel). They are general purpose MOSFETs and should work well enough for drop-in replacement.
If it is not the MOSFET, power supply or the heater, then I have no idea.
You should be able to trace one of these loops:
power supply -> (fuse ->) heater -> n-channel MOSFET -> power supply
power supply -> (fuse ->) p-channel MOSFET -> heater -> power supply
Most likely will be the first loop.
NOTE: Checking the heater resistance might help but does not have to. At room temperature the resistance might be within limits (as with mine example) and when heated up the resistance increases with temperature and thus limiting the current. You would have to measure the resistance when heated up and disconnected from all circuits. (Heat up -> disconnect heater -> measure -> cooldown).
Hope that helps and good luck.


Which nozzle should I buy for Anycubic i3 Mega?

According to Anycubic this printer uses the E3D V5 type hotend as can be seen from the linked video of the AnyCubic Mega:

The brass nozzle you see is fully compatible with the E3D v6 nozzle and can be found on those typical auction and Chinese websites by looking for "E3D nozzle". They are also available from E3D directly, the designer/creator of the E3D hotend family, and other specialized manufacturers like the Olsson Ruby. These nozzles have a short nozzle (snout) and are screwed into the heater block with M6 threads.1)

The smaller the diameter, the smaller the filament traces and the higher the print detail resolution. Note that a smaller diameter causes thinner walls for the same amount of (vertical) walls and may require additional perimeters to get similar strength and rigidity. The maximum layer thickness also decreases, as prints with a layer height above 75 % of the nozzle diameter have very poor quality. As an example, a 0.25 mm nozzle should not print layers thicker than $0.75 \times 0.25\text{ mm} = 0.19\text{ mm}$.

As such printing with smaller nozzle diameters increases print time. Also note that a smaller diameter requires more force to push the filament through and could use some extra temperature to make the filament more fluid or reduction of the print speed.

Just buy some spare nozzles of different nozzle diameter and experiment what works best for you.

1) - The other popular style of M6 threaded nozzles has a long body and long taper (often referred to as MK8 nozzle; they come in two different shapes). While these might work, they extend from the heater block considerably further and might need readjustment of the heater block (as explained here):


I’ve bought two printers (CR-10S and Ender 2)from Tiny Machines in Houston Texas.  They unbox them from China and assemble them and make a test print.  You get a checklist of the tests performed.  They will also flash a bootloader and updated Marlin for $10.

Yeah, you’ll pay more but if you spend any time in printer forums you’ll hear lots of complaining about missing/broken parts or DOA units.

They also stock spare parts here in the US.

Good luck to you!


What's the best way to clean PETG residue from a magnetic steel sheet PEI?

First you will want to verify that what you are seeing is remaining PETG and not a loss of PEI on your bed. In many cases, when PETG is used without a separating agent (window cleaner or glue stick), the PETG forms a stronger bond to the PEI than the PEI has to the bed. This causes the PEI to lift off the bed. You can often recognize this by seeing a spot of higher smoothness where the print was stuck rather than the more matte look elsewhere on the print bed.

If it is truly PETG left on the sheet, first try a firm use of a fingernail. If that does not work, you can attempt to use acetone or 1000 grit sandpaper (which also work to restore PEI). A careful use of a spatula can also be used to remove the material.

In subsequent prints of PETG, you will want to add a separator when printing PETG.


This sounds like a clogged nozzle. Try driving the filament into the hot end manually to verify that the plastic is flowing correctly. If there is a clog or other impediment in the nozzle, the filament will become curly as it is exiting the nozzle. A clear nozzle will always result in the filament extruding as one straight piece.


Cleaning the nozzle every Xth layer G-code

There are extensions for Cura that can do almost what you want to do for you (with respect to the layer or height).
You need to add post-processing scripts to the Cura slicer. You do that from the top menu options Extensions -> Post Processing -> Modify G-Code and then add the option of choice.
E.g. for an event at every layer change you should use script "Insert at layer change" and fill out the G-code you want to perform.
There are options to write your own extension, but that would require some software development skills.
Optionally, you could use the "ChangeAtZ" script to add absurd temperature changes of the extruder to post process that later by a simple e.g. Python script (outside Cura) to replace those actions with the cleaning actions you want to perform. But, when you can do that, you could write a script outside Cura to detect the layers (e.g. from the comments or from the layer change command G1 Zxx) and insert that right away.
For inserting this on the basis of time would be very difficult, it is difficult to estimate the time printing actions take to then inject such a script.


Try using a pancake stepper I heard those work quite well, they do have less torque but you can overcome that with gear ratio's like on the bondtech extruders. It should be thin enough so you can use the full volume again. If you dont think that's worth it you should move you X-axis endstop since the homing is where it goes wrong, as far as firmware goes I can't help you in that aspect as well as other would be able too. I hope this helps.


Ender 3 Pro, Motherboard v4.2.7, Marlin 2.0.1 Firmware reset

You could download the firmware version directly from the vendor and choose the one that is supposed to be on the board when it was shipped to you.
Put the bin file on the SD card from your laptop/computer and reinsert the SD card in the printer and start the printer.


How to make physical buttons send G-code?

One option would be to have your printer controlled by an Octoprint server.  You would then use the Octoprint Api plugin to use your arduino to send commands to octoprint - and from there, your printer.  Octoprint has a fairly fully-featured rest api that allows you to send arbitrary GCODE to your printer (see here).  You would then hook up your buttons to some code that sends the gcode commands to the printer when pressed.  It's certainly not as simple as installing a plugin - you'll have to write some interface code, but it looks like those APIs should be able to do what you want, without interfering with the standard controls at all.


What are the advantages of gyroid infill?

From this reference you can read that:

  A gyroid is a naturally occurring structure which be found in
  butterfly wings and even within membranes inside cells. In 2017, MIT
  researchers discovered that when graphene was shaped into a gyroid
  structure, it had exceptional strength properties at low densities.
  They then discovered however, that the crucial aspect of this was
  actually the gyroid structure itself, and that other materials such as
  plastic could benefit from this.

It is assumed that this type of infill has better properties against failure than the normal types of infill we know.

A test conducted by an author named Martin is found here. He printed test specimen and subjected them to bending to test the resistance against shear stress.

From the figure can be concluded that the gyroid infill has a better resistance against bending for a lower weight.

The advantages of gyroid infill over the tested infill types are:

high shear strength, and
low weight (so less filament needed).

On top of these advantages Gyroid infill prints relatively fast with respect to some other infill types and is close to isotropic (i.e. uniform in all orientations), meaning that is very suitable for flexible prints.


How do I keep my extruder head from getting clogged?

Different types of hotends and extruders can lead to different problems associated with clogging. Based on my personal experience the leading causes of clogs and jams are the following

Foreign material in the nozzle (dirt, dust, low quality filament)
Mixing materials in the hotend (running ABS at 220 then switching to PLA without purging the nozzle)
Excessive retraction or "heat soak" in PLA (PLA expands when heated if your retraction is set to high you can actually push the expanded PLA high enough that it cools down and can no longer flow)

To solve these issues I recommend using one type of filament, preferably decent quality (typically $40 per kg), if you swap materials be sure to completely purge your nozzle of the higher temperature material. Set your retraction as low as you can trying to minimize ooze (try .4 mm for all metal hotend or 2-3 mm for makerbot style). To minimize carbonized plastic in your hotend don't leave your hotend's heater on for extended periods of time. One way to keep dust from accumulating on your filament is to cover your rolls when you aren't using them, I personally use hairnets, you can buy a 12 pack for a couple of dollars and they last for a long time.


Printer is Confused-Printing in Air Literally

Here's the pattern.

The problem is, you didn't slice the g-code using support. It won't print right without it.


Ender 5 SKR Mini E3 -- After Heating the Hot End Assembly Runs into the side of the printer

So I found an answer on Reddit when I asked the same question: It actually had to do with the homing -- basically, it was starting at 220, 220 instead of 0,0, which resulted in when the print started for it to head straight into the corner. In order to counter this, I had to change some of the firmware. Everything works now. Thank you for your help!


tl dr: For the most part, yes it should be color fast in the sun. It should be good for outdoor use.

This website claims the following:

  Filament materials ... for outdoor use include ASA and PETG that are perfect for use in extreme conditions without changing shape or appearance. Printed pieces do not change colour either with the sun's UV rays and do not take on a yellowish appearance as does ABS, for example.

Please realize, this is partially an advertisement (and no, I have no affiliation). What it boils down to is, PETG and ASA are going to be better for outdoor use, but every brand of each is going to be a little different in how well it reacts to the elements. Without advertising on the site, you'd need to do a little investigating on your own, with the possibility of testing different brands to come up with what you believe is the best. Beyond that, it's just an opinion.

I doubt any filament, no matter what it is made of, is going to be perfectly colorfast in the sun. The sun is a harsh beast. It will bleach a printed object over time. Some colors are going to be more susceptible than others, especially red. This is due to the color of the sun. Again, some filaments are going to be better than others, but I'd not expect any filament to be perfect.


Printing .stl file using ObJetPro 3D Printer

the best way is to install slicer on your pc and open the .stl file.
Most slicers will tell you the size of an object and there is an option to rescale resize.

Using Slic3r you will have object details in the corner

Using CURA you will have a detailed view in scale mode

Also you can use online services CLICK


Holes/ missing layers (after retraction) in 3d printed objects

(answering my own question)

The problem was the extrusion distance settings in Cura's advanced tab, reducing the value to 1.5mm solved the problem.

Other problems with the same symptoms:

Partially blocked hotend nozzle.
Incorrectly configured steps per mm for the extruder motor - this youtube video shows how to test and configure this.


Do you have trouble with 3D printer on UPS during short power outages?

Part of your self-answer:

  What is puzzling is why did the 3D printer run as if the computer was still operating it, when is was printing from the SD card? Was the circuitry getting power from the USB cable from the computer?

is more of an extension of the question, which I'll answer. Generally, yes, the logic of many (most?) 3D printers can be powered by the USB connection. You can try it sometime with the printer not plugged in to the AC power source at all. Under such a power configuration, the motors (not to mention the heating elements) should not operate at all, and I think the firmware has logic to detect this condition and not try to print under it, but I may be mistaken. However, in any case, in the event of an outage during printing, the logic board will remain powered if it's connected by USB, and especially if the outage is short enough, it might not even notice that the motors and heating elements are not functioning, yielding a result like what you saw.


Large flat ABS print curling during cooldown

Short Answer: Make the environment temperature is a bit warmer to offset the cooling rate.

Long Answer

All materials shrink as they cool, but some materials shrink at a much higher rate than others. This is primarily driven by temperature coefficients and thermal conductivity of the individual materials. There are calculators available online that you can get more involved with discovering how this works mathematically.

However, in layman's terms, the temperature between your build plate and the first layers of plastic are so drastically different, that at a certain point the plastic becomes under tension as it shrinks faster/more than the build plate. Over time, since the surface tension between the part and the build plate is no longer in the way, the corner can continue to shrink.

Here are some options:

Ensure your build plate temperatures are correct acceptable. I've had success with 112C in NW United States. Increasing the temperature will be an attempt to bridge the gap between BP temps and plastic temps during the final cool-down.
Search for ways to "anchor" the part to the build plate. There are lots of resources on the internet on how to do this, so I'll spare you the list.
Increase your environment temperature. I highly suggest this because it can help reduce other errors you might encounter throughout the printing process, such as de-lamination, warping, brittleness, etc. I'm not recommending placing a space heater next to your printer (really, don't do that!), but perhaps even a space heater in the room can help regulate the environment temperature a bit better.
Consider other environment variables. Consider things like "Is my printer next to a window?", "Do I live in a particularly cold environment in general?", or even "Am I baking cookies in the next room?". A lot of these seemingly meaningless variables play an important role in ensuring quality prints.

(I know there's more, so I'll add onto this answer a bit more as I remember them)


After replacing the control board, it now prints flawlessly. Apparently,I really did damage the control board...


Making Polyurethane molds with PLA (or ABS) 3D printed master

Temperature
As polyurethane cures (or hardens), it undergoes a chemical bonding reaction, linking the mono- and oligomer strings in the components into long polyurethane chains. The chemical reaction is exothermic, it creates heat.
So, we have a process that heats up the polyurethane mixture as it hardens, but how much? Well, it's hard to find numbers for it, but I suspect it can easily reach 30 to 40 °C, depending on the mixture (fast curing) it could easily go higher. To combat the effects of heat softening of the PLA/ABS model inside the mold, I strongly suggest printing with extra shells and extra infill. While most items can get away with 10 %, in this case, I suggest 20-30 %. ABS would be the superior choice above PLA as it starts to deform at a higher temperature. PLA can start to deform at around 60 °C, ABS only at about 80 °C.
The temperature of the PU curing depends on the speed of the curing process - it is safer for the masters to choose a slower curing mix as the heat is generated over a longer time and the maximum temperature is thus lower as a result (as excess heat is lost to the room)
Surface
To reduce the sticking to the surface from the material creeping into the gaps of the model, it has to be as smooth as possible and best also sealed. If you choose ABS, a quick acetone vapor bath would do the trick in this case. PLA should be lacquer sealed as it doesn't like to stick to most waxes.
Adding a mold release agent isn't necessarily needed, but could help in removing the masters from the mold.
Conclusion
ABS might be the better choice in this application. It is advisable to use extra-thick walls (3+), a lot of infill (20-30 %) and a vapor smoothed surface.


Will glue sticks form a barrier on a build surface to prevent PETG from damaging the surface?

I don't know about PVP but PVA sticks more at room temperature and gets weaker at higher temperatures, see "Influence of temperature on the strength of bonded joints"

I remember using hairspray with PVA for PETG and it was really difficult to detach large parts.


Configuring BLTouch with Marlin firmware

For security reasons, you cannot move Z until home position is applied to X, Y and Z.

With the level sensor attached, we need to home X and Y, and then Z will be homed in the middle of the bed (as configured). Execute G28 to home all axis and then you shall be able to run 'Z'.

To test that, you can unplug just steppers (with power switched off to prevent damaging the stepper drivers) and move X and Y manually to home position, then just give a touch to the BL sensor (when servo/pin) is deployed to confirm home position.


Trying to flash Davinci XYZ 1.0, nothing but black bars

I had this occur on my MakerBot Replicator Dual after I tried repairing a blown voltage regulator. If you refer to the previous link to my SE question, pay attention to the comments of Ryan's answer where it is explained that (in my case at least) the main processor was damaged and therefore couldn't properly load the firmware. The machine was able to load just enough to initialize the chip on the LCD screen, but since the main boards processor was blown, couldn't load the firmware to send commands to the screen and continue the boot sequence.

I'm not certain that you're encountering the same EXACT issue, but you have all of the same side effects that I did. Basically, if you're not pro with electronics, your board is bricked. Otherwise, you might be able to salvage the board by replacing the processor, but there's no guarantee that something else isn't wrong or that the new processor was installed correctly.


Which filaments actually do need to be stored in a drybox?

PVA
From experience I can tell that PVA filaments need to be stored with silica beads in a plastic bag or in a specific dry-box. PVA is soluble in water and is very hygroscopic. With moisture it gets soft and swells. My Ultimaker came with an open spool of PVA which popped when heated (steam bubbles popping) resulting in very poor quality supports and clogging of the nozzle. A newly bought spool which was properly packed did not have these issues.
Nylon
Some Nylon filament brands require to be stored dry or need to be dried before printing. I have a spool of Nylon that has taken up some moisture although carefully packed, the only time it was out is when it was being printed. This experience applies to Ultimaker Nylon; I've learned now that not all Nylon filaments are behaving the same, it is suggested to look-up the specifics from the manufacturer or from reviews prior to buying.


Makerbot Smart extruder+ heat block and nozzle question

Caveat emptor: This answer is probably not what you're expecting.

As far as I can make out after looking at this un-jamming video on YouTube, where at time 00:01:24, the video shows a label that needs to be cut to open up the extruder. However, as mentioned at the end of the same video, cutting that label will void Makerbot's warranty cover on the extruder.

From that, I can make out that Makerbot will actively discourage any efforts to disseminate the kind of information you're looking for, at least until the product is discontinued. That would usually include a DMCA takedown notice to Google to remove search engine results, as well as similar takedown notices to other places where such information is hosted. I expect you will not find such information easily.


After looking around for a bit in Cura. You can update it via Cura.
Start by going to your printer -> Manage printer
Then there is the option to update firmware. You must plug the printer in first.


How thin can my extrusion be from a 1.2mm extruder?

The main issue with very narrow extrusion widths (less than the nozzle size) is that you get really poor "nozzle squash." The plastic isn't pressed down very hard as it's extruded. That causes poor layer bonding and weaker prints.

The flow of molten plastic coming out of the nozzle must be drawn down by tension in order to end up smaller than the nozzle opening, and that drawing effect makes it difficult to get good contact with the previous layer. So you end up with a "stack of logs" structure kind of like this:

(This photo actually shows layer height = extrusion width = nozzle size, which is another no-no, but the end result is similar.)

What you want instead is something very "mashed together" and strong like this:

How finely the the strand can draw down -- versus smearing or breaking apart into blobs -- will depend greatly on the type of filament and the printing conditions. For example, nylon draws down extremely well because it experiences a large degree of strain crystallization, and actually gets stronger and stiffer as it's stretched. PLA tends to get more brittle when strained and may break into stringy blobs. ABS doesn't change terribly much because it's highly amorphous. Polymer type, blending agents, print speed, printing temperature, and cooling will control the drawing behavior of the filament.

Another factor to consider is what the strand spacing is within the print. If you set the extrusion width equal to half the nozzle width, depending on the slicer, adjacent strands may be placed with pitch equal or slightly less than half the nozzle width. So after the first strand is printed (say an unimportant inner perimeter) the next strand will be printed with the nozzle partially overlapping the previous strand. This effectively creates a constriction to force the plastic out of a smaller opening to one side of the nozzle, which is not too different from printing with a smaller nozzle. Subsequent perimeter strands may then tend to "heal up" even if the first is low quality. This effect doesn't completely fix the problem, but it helps account for why under-width strands seem to work better than they ought to.

Of course, even if the strands turn out ok, it's arguable whether there is any benefit. If the goal of a smaller extrusion width is more precision and sharper corners, you may not actually accomplish that goal. When the filament is being drawn down by tension in the cooling polymer, it may tend to "cut corners" and get pulled into a rounded arc when the nozzle changes direction. That may defeat the point of using a thinner extrusion width in the first place. Generally I only recommend using under-width strands to capture thin-wall detail that is only a little bit too thin for the nozzle, not as a way to improve overall print quality.

In comparison, having the extrusion width equal or wider than the nozzle ensures the plastic is firmly squished downward into intimate contact with the lower layer. You can fudge this a bit and still get decent results, but it's usually best to keep the extrusion width equal or larger than the nozzle size. There's no hard cutoff where it will / won't work.


I agree with @FernandoBaltazar. You have several things going on. If the problem is recent, you may have loose belts, but you may also need to perform acceleration and jerk tuning. Reducing your print speeds may also help.


octopus8 recommended doing a series of tests to determine the cause of the problem.
I started with moving the bed by hand (remember to have machine off or choose "Disable steppers" from "Prepare" menu) and the movement was relatively smooth with some resistance, the same as when moving the X-axis.  If you move very slowly you can feel slight, small "steps", this is normal. The movement was consistent across the range of movement.
Since this did not indicate a problem, I moved on to checking the drive belt and the bearing wheels.  The belt had a small amount of slack which I tightened.  Several of the wheels under the bed slipped against the rail they run along.  I tightened these.  This improved the movement of a couple of them but a couple still slipped a bit.
After this I did not have the problem anymore.  For 10+ prints over a week or so, there was no incorrect Y-axis movement and "Auto home" always worked. Nevertheless I continued with the next test suggestion which was to send some simple gcode to the printer via USB.  I used both Ultimaker Cura 4.8.0's Monitor mode as well as [sending the commands from the linux terminal][1].  I sent the commands
G28
G0 F<speed>
G0 X200 Y0
G0 X200 Y200
G0 X0 Y200
G0 X0 Y0

with values of 900,1800,2700,3600 and 4500 for  and everytime the print head returned to the same place.
This is evidence that the tightening of the belt and wheels likely fixed the problem.
[1]: How to directly send G-code to printer from a Linux terminal?


Calculating extruder motor steps for 1 mm

Microstepping. Your board likely has 16x microstepping, so that each step is divided up into 16 parts. Your 5.787 figure, when multiplied by 16, comes out to 92.6 steps/mm - matching the value in your firmware.


Looks like curling from to much being extruded and no cooling I had the same problem added part cooling and problem was gone


Is 3D printing a good way to save money?

I would say that the general answer to your specific question is no. If you want to justify buying a printer because of all the things you could print instead of buying that is not going to be easy.

If however you are a DIYer and you have some CAD skills, or are willing to learn some, then consider the 3D printer as another tool you can use. There are plenty of stories about people who fixed some very expensive thing instead of having to buy a whole new one for hundreds of $/£; so if you have a specific use in mind then it may be justifiable to you.

I have made and fixed stuff around the house, but it's often things you simply couldn't buy, or could have fixed some other way.

There is an ever growing library of models available out there, and many are free. I recently fixed the leg on my keyboard with a printed one which I found on thingiverse, took minutes to print and the keyboard is part of a wireless set which would cost £30 to replace, so that was great but you won't normally find exactly what you want like that at this time.

And lastly it's not plug 'n Play yet, so you need to be a tinkerer at heart to use most printers out there right now.


Looks like you didn't include a space between the -i flag and the file, though you did include the space in this question. Try running the command but include spaces between your flags and file directories:

recon-all -s mybrain -all -i /home/fsuser/Desktop/brainscan.nii


Printing with PETG, printer says it's out of filament when it clearly is not

Shoutout to @0scar for posting a photo of the filament sensor, that was super helpful. Also thanks to everyone else who pointed me to the filament sensor and resources around that.

I also tracked down this review which had great information around my printer's filament sensor as well. It turns out that the hole that goes to the sensor is way too big and there's a lot of play with the filament. As I jiggled the filament up & down I could hear the sensor clicking on & off, clearly indicating that if the angle of entry of the filament was too low, the sensor would not be depressed and this would continue to be a problem.

So for my next print, I did what that reviewer suggested and simply unscrewed the sensor & taped it so it would not stop my print. My print was unsuccessful for other reasons (under-extrusion/failed to adhere to the build plate ), but at least I think I've figured out what's going on with my filament sensor. Thanks again everyone!


How to start a print in the center position after a change in parameters using M92 and M500 G-code

Every time I.m will go to print, if turn off the machine, the process to be need repeat, in other words, the gcode M500 doesn't work.

This tells me that your firmware has the EEPROM support needed for the M500 command disabled.
Fixing the firmware
You need to update your firmware to enable storing the information in the EEPROM: the line should read as follows without any leading //
#define EEPROM_SETTINGS // Enable for M500 and M501 commands

When you are already updating your firmware, you should also fix your firmware to have the correct steps/mm, as those are off in your build. An example for the line you look for is
#define DEFAULT_AXIS_STEPS_PER_UNIT   { 106.64, 106.64, 4000, 500 }

Workaround
automatic setting of the Steps/mm fix
There's a way to fix it on the user side though: When slicing, your Start-G-code needs to include M92 X106.64 Y106.64, best before homing. That way you make sure that your printer sets the correct Steps/mm whenever you load a printjob.
Home position
via offset
If the home offset is wrong, you can fix it as the next line before G28 - if the home position is for example 10 mm of the trigger in both X and Y, you'd add M206 X100.00 Y100.00 Z0.00 - If your printer has "home" properly defined in the center of the build plate and your slicer is set up to respect that, this should do it. You need to
via move and 0-ing
Another way to get the printhead to the center is to use first G28, then insert a movement to the center of the bed (G0 X100 Y100 for a bed 200 mm across) and then order G92 X0 Y0, defining that point as the origin.
necessary next line!
In either case, the setup of Marlin also prevents you to move to the "negative" area due to the software endstops by default. So you need to add M121 after it to be allowed to go into the negative space.
Start G-code in bulk
M92 X106.64 Y106.64
G28
G0 X100 Y100 ; move to center
G92 X0 Y0
M121


How do I know if a filament is abrasive?

A filament made of pure plastic won't be abrasive. The abrasion comes from the added particles.
Filaments with added particles of any kind (there are not so many after all: glass/carbon fibres, metals, glow in the dark, wood, stone) will usually be always be advertised as such because they always carry a higher price tag compared to the plain plastic, therefore you know that it contains potentially abrasive particles.
Once you know that particles are added, most of the time they will be abrasive: as far as I know, only cork is not, any other kind of particles I listed (including wood particles) may easily scratch brass.
If it were your printer, we could discuss how much each kind of particles will abrade, but in your case the ban seems to be complete, therefore only plain plastics (including "plus/+/Pro" blends, like for PLA and ABS) are allowed.


Understanding of the auto bed leveling process (BLTouch)

What may be confusing is the use of the naming of the mechanism "Auto Bed Levelling", or short ABL, does not make your build plate to level itself with respect to the frame of the printer1). Hence you are instructed to always tram (level is rather misleading as it doesn't involve bubble levelling, instead it is meant to tram the bed with respect to the X- and Y-axis) the build surface as good as you can.
The ABL process could better be described as "Height adjusting to scanned bed geometry" or something like that, as that is exactly what is being done. The G29 command scans the bed surface and (depending on the firmware options) it generates a mesh or a plane through the measured points. When printing, the nozzle will follow the bed height geometry and fades this out over about 10 milliliters (depends on setting). So, if you do not tram the bed correctly, you will end up with a skew bottom of the print as the fade out will cause the printer to print eventually parallel to the X- and Y-axis.
Note that specifying the Z-offset in the firmware is rather useless, you cannot measure this beforehand. It is far better to do this later using M851.
This answer describes in some more detail how the offset is generated and applied to the scanned surface.

1) It is possible to actually level/tram the bed (e.g. in Marlin firmware), but that are different processes. E.g. a tramming assistant is available when using the G35 G-code. And, automatically, (for specific printers) possible on build plates that are moved up/down by several lead screws (look into NUM_Z_STEPPER_DRIVERS in Marlin's Configuration_adv.h file). But still, this maintains a certain level, it does not scan the complete surface, that can be achieved by the ABL process.


How can I export a Materialise Magics Project as a STL file?

Instead of using save project as or export click save part as, this defaults to an STL file.


Can PLA carry sound coming from a loud speaker?

In space, no one can hear you scream. That's because there's no air to be vibrated, which is part of the definition of sound.
In the case of your model, the described diaphragm will generate sound because it is surrounded by air. The vibrations in the air will transfer (and reflect) from the PLA shell you've created.
In order to hear as much sound as possible, you have to have as thin a shell as possible and only one of them. It would be more effective if you could incorporate the membrane into the shell, which eliminates the sound damping effect of the plastic sphere.
Barring that option, one layer (vase mode, but probably not) would present the created sound with a much less massive amount of plastic to vibrate.
Additionally, PLA is not known for being water tight. One can apply epoxy or other sealants to make it so, but that will add mass to the overall equation.


Issues in X-Y size on a Delta are usually the result of an incorrect diagonal rod value in the firmware.  This should be easy to fix assuming the rods were built together.

The formula for this is (20 in this case is your test print X-Y):

New DELTA_DIAGONAL_ROD = 20 / measured_length * Original DELTA_DIAGONAL_ROD

I found this information (here), this site also has more information on setting the radius and other delta specific issues.

If you encounter issues with the size of the rods you should build new ones using a jig.  There are several (here's one) I found on Thingiverse but they require printed parts and they do all the rods horizontally which I think would be tough to keep equal. I would use something similar to this picture but with a longer rod/bolt so you can fit all rods on the same time.  When I did my Kossel Mini I used a piece of the extrusion with bolts coming off of it to keep the rods consistent.

For the other issues you mention you should open another question specific to each issue.


3D Print something as flexible as a cloth with PLA?

Maybe you would be better off with TPU or some other type of flexible material...

I have been able to print PLA and have it flex quite a bit, but that was an ~0.2mm single layer print, I guess maybe up to 0.3-0.4mm should still be a little bit flexible, but not much. Also since you want it to wipe things, maybe you should look if TPU even has all the properties required for that as Carl mentioned in the comments.