"Err: MAXTEMP: E1" when THERMAL_PROTECTION_HOTENDS is disabled

#define THERMAL_PROTECTION_HOTENDS is for thermal runaway. When the temperature "should" be climbing or falling at a predicable rate, or holding steady once at running temp.
#define HEATER_0_MAXTEMP defines the maximum temperature Marlin will allow the extruder to get to before initiating a shutdown. This is ALWAYS active for an active extruder (E0) This setting is what will throw MAXTEMP if it is exceeded.
MAXTEMP error when there is no heat on is usually from a short in the thermistor cable.


101Hero 3D Printer - Printed object is tilted

You appear to have a couple of issues here,

First off your nozzle appears to be a bit hot for your filament (you can see this be the drooping and sagginess of the layers on the outer shell)

Second issue is it appears as though your belts are loose. You can tell if your belts are loose if your parts seem to be shifted in one way.

Third issue (maybe). You may want to try slowing down your nozzle speed slightly. The faster the extruder moves, the more inertia that is generated which in effect makes your belt act as a spring and will cause it to bounce along the axis while it's printing. Slowing it down will result in your belt acting more like a rigid member and help to clean up the outer layers of your print. Also, it's easier on your belts. The downside is that your parts will take a bit longer to print. In my experience, parts that look great but take a bit longer are well worth the wait.


When do I need to get a BLTouch upgrade?

A touch or an inductive or capacitive sensor are useful when you cannot get a completely level bed which can be caused by a skew bed platform/heated plate or if the plate has a bend, large concave or convex area.

Even with such a sensor, you need to provide a bed that is as level (trammed) as you can get. Automatic Bed Levelling (ABL) is not magic, it is just a tool that can help out if you have a problematic bed surface. But, recent versions of Marlin have "manual bed levelling"; i.e. you can map the surface using your printer without a sensor and store that geometry in memory.


Reprogram Marlin to assign endstop pins to arbitrary tasks [Arduino Mega]

Apparently, given one

has already enabled USE_<AXIS>_PLUG (for example
<AXIS> = XMIN) in Marlin's Configuration.h,
one can add an additional define (for example <AXIS>_ENDSTOP_CUSTOM) in
Configuration.h and
make this block the else statement in an
<AXIS>_ENDSTOP_CUSTOM existence check, with the positive case being your
arbitrary task.

The function that gets executed in the standard case in the linked block is PROCESS_ENDSTOP, so cloning it would be a good starting point to make a PROCESS_ENDSTOP_CUSTOM task, too.


You are mixing and matching a few older techniques. That's understandable, because "older" means "as of three months ago." But there is a better way now: as of version 2.0, the SKR mini has a full, working port for the BLTouch. You do not need to plug it into the z-stop, and you can and should retain your existing z-stop switch.
So:

Power down your printer and get access to your board.
Roll back your hardware changes by unplugging the BLTouch and reattaching the z-stop switch.
Plug the bltouch into the port labelled "z-probe", which is next to the display port. Starting from the pin nearest to the stop switches, the pin order should be Brown, Red, Yellow, Black White.
Optional: instead of the step above, cut the DuPont connectors off the BLTouch cables and crimp a single XH-5Y connector in their place, then plug that into the board.
Download the official BLTouch firmware from SKR mini: https://github.com/bigtreetech/BIGTREETECH-SKR-mini-E3/blob/master/firmware/V2.0/firmware-bltouch.bin
Install that firmware: Rename the file to "firmware.bin", unplug any USB cables from your printer, copy the file to a MicroSD, insert the MicroSD into your printer and power it on.

...and then it should work.


Yes, it has been done before, see here and here.

The README file of the first repository linked above contains a detailed explanation of the basic idea/calculations involved.  A short excerpt:

  As you can set the parameters of G1 in such a way as to precisely control the velocity and the distance of a movement along a certain axis, you can control the operation frequency of the stepper motors as well as the actual time to complete a movement.

On another note (pun intended), you can also play music by using the code M300.


Oven drying PLA

Heating filament below the transition temperature of the filament should not be unsafe when using that oven later for cooking food. You need the temperature to stay under the glass transition temperature of PLA so that the filament doesn't deform. Depending on the PLA filament, you should use the very lowest temperature your oven will be able to handle. Temperatures around 40 ℃ to 50 ℃ would be fine to leave the filament in for periods of 3 to 6 hours. Even at this temp your PLA will soften anyways at elevated temperatures, oven drying PLA not necessarily will give you good results. It is therefore of prime importance to store at least PLA (and nylon) in airtight containers with bags of desiccants.

Stuck PLA

Moisture will not travel that far into the hotend, so changes are minimal that expanding filament has already damaged your hotend. Just heat up the nozzle and push the filament in by hand, put off the heat and pull the filament out fast. Heat up again and insert some fresh filament. Note that moisture in filament breaks the large polymer molecules, so even after drying you are left with brittle filament. Personally this has caused few of my prints to fail as the filament string broke a couple of times during prints (just snapped before the Ultimaker 3 extruder feeder); this was experienced with 2.85 mm filament on small diameter spools (about 20 cm in diameter).


On a LENS printer, does the head move, or is it table that moves when printing?

Whilst this is not a definitive answer, if you watch the video on their website, LENS 450 Systems, it is the bed that moves in the X and Y axes - the head remains static. The bed also appears to move in the Z axis, after each layer (as there is noticeable bed wobble).

However, the head is on an armature so it could be that which moves - it is not entirely clear.

LENS 450 System for 3D Printed Metals

Note that the MR-7 system appears to be similar to the 450, with its "3 Axis CNC Control System". However, the 850-R differs, inasmuch that it has:

5 Axis CNC Control System
XYZ gantry + tilt-rotate table

which are not mentioned in the specifications of the 450 and MR-7, so the 850-R could well differ from the video.


I found the solution :
It was the option "avoid crossing perimeters" that seems to do exactly the contrary of what it means.
Thank you all for your answers.


The mystery is solved. The BlTouch probe was slightly blocked and reported (supposedly) being in touch with the plate. Just touching it released the probe from the stuck position and all works well now.
Due to direct sunlight, I overlooked the warning blinking red colour of the BlTouch.


If the fitting is remaining attached to the PTFE tubing, that would indicate that the threaded end of the fitting is pulling out of the drive assembly. This implies that the internal threads of the drive assembly have stripped out. This is not unusual for a plastic drive assembly.
The best solution is to replace the drive assembly. I believe I paid about US$12 for the last one I purchased and it was aluminum, not plastic. A quick search for "Ender 3 drive mechanism" returned a number of choices. One of them from Amazon (14.98) is anodized aluminum and purports to be improved over the original.

A less than ideal solution would involve drilling out the stripped threads and installing an insert (sometimes called a Heli-coil™) but that could be as expensive as a replacement mechanism.


New Build. Hotend Overheating. Not Printing Yet

3.9 ohms is a 12V heater.  It won't work on 24V.


What are the specifications of the dual voltage controller of the Ender 3/CR-10?

I own the Ender 3, and it runs on 24V, as this photo of the power supply shows:

From power supply  to the board, it uses a 2-wire line connected with a XT60 plug/jack that is common on RC cars:

The board itself is a proprietary design and labeled as "V1.1.2". The Voltage in is the lowest input on the left:

The Cooling fan (blue-yellow wire), the hotend cooling fan, heater cartridge (white shielded), bed heater (left black-red), board cooling fan (middle red-black) run (in this setup) on 24V. The Logic connectors (black-black & White-white) run 5V logic. I could not figure out the voltage of the stepper motors (upper row).

I have not figured out how the power management circut works, but it achieves this:

Supply voltage $ U_S = 12V \lor 24V $
Logic Voltage $ U_L = 5V $
Sensor Voltage $ U_{sens} = U_L$
Hotend Cooling Fan $ U_{cool} = U_S$
Hotend Heating Cartridge $ U_{hot} = U_S $
Heatbed $ U_{bed} = U_S $

The chip's caption can't be read on the photo, but it is labeled as "Δ ATMEL // ATMEGA1284P // AU 1726"

For the pinout, a german maker did determine, that it the configuration of a Sanguino equipped with an Atmega1284P 16Bit works for compiling firmware and flashing via a bootloader.


What kind of aluminium grade for a heated 3D printer bed?

Various grades and alloys of aluminum will have characteristics related to ease of welding, resistance to corrosion, malleability, and other aspects. For a heated bed on a 3D printer, you'd really want to have something resistant to warping and something that can be assured to be planar across the surface, that is, flat.

The terminology you'd want to use for your search is "MIC 6 Cast Aluminum Tooling Plate" and the results are many.

From a rather comprehensive web site:

Flatness tolerance is maintained within .015" on 1/4"-5/8" thickness and .005" on 3/4"- 4" thickness. Thermal Cycling can be performed up to 800° F  under controlled conditions.

You would want to confirm from the seller that the surface has been prepared, as some sites appear to sell un-finished tooling plate, but I've not been able to clarify that. Most appear to provide either no specifications regarding flatness or give a figure such as that above.


The symptoms you describe hint to heat creep. Heat creep is the gradual increase in temperature of the cold end assembly (cooling fins and heat break). This gradual temperature increase leads to too high filament temperatures and as such premature filament softening. In combination with (large) retraction settings, this can lead to clogging of the nozzle. All-metal hotend assemblies are more prone experiencing these problems; lined hotends have a PTFE lining that also insulates the filament so that it does not soften prematurely like in all-metal hotends can happen. Heat creep is best remedied by properly cooling the hotend (good quality fan, no obstructions or large ducts) and reducing the retraction length (and possibly lowering the print temperature, but you already tried that). You could also contact the manufacturer for advice.


The closest thing you will find is Woodfill plastic. As time goes on we are seeing more and more PLA that is infused with other materials. Woodfill will look and feel like waxy wood. We are pretty used to seeing fiber boards and the like so this will not come off as odd. However it is not quite cardboard, except that it is also a wood product. It will also smell of wood.

Here is a close up of a beyond exceptional wood fill printed piece. There is also other types of wood fill including bamboo.

I mean if you want Cardboard.. Why not a laser cutter? While you can get a MUCH cheaper laser cutter, the glowforge comes to mind.


When you want to change an STL file in FreeCAD then this is how I do it. I open the STL file in FreeCAD and select the option in the Part/Component sub-menu: Make a form from mesh (hope that I translated it well. I use the Dutch version). It can take quite some time but when it is finished you have an editable object. Just remove the STL object and do what you want.

When you finished then you can perform all actions like if you created it from scratch with FreeCAD.

I am a beginner in 3D design so there might be 'smarter' solutions. When I want 1 special part then I create as many cubes as needed and perform a MINUS action on the solid and a cube. After a while I end up with only the part I need.


I believe what you are experiencing is the stepper motors getting offset during  the print, usually due to the nozzle colliding into the model (but possibly also due to very high printing speeds).

Basically, the stepper motors used in most 3D printers will always make moves relative to their current position (as opposed to absolute positioning). In other words, the stepper will for example be told to move 10 steps left, regardless of where it is currently at. If you therefore forcefully move the printhead out of position during the print, the electronics will never know it happened, and continue with instructions that are no longer viable.

In order to fix this, do what you can to avoid the nozzle colliding into the model:

Make sure your printer does not leave large deposits of filament, typically due to over extrusion or too close Z-leveling of the first layer.
Make sure the model sticks to the bed, so that warped parts don't lift up, obstructing the toolpaths.
Add Z-lift in your slicer software, so that the printhead lifts slightly between travel moves.
Reduce travel speed (if it is set very high): the strength of stepper motors is lower at higher speeds, which means nozzle collisions at higher speeds most likely will offset the motors.


Filament Leaking During Automatic Bed Leveling

The oozing is due to hot-end getting hot before the bed leveling procedure: if you move the hot-end warm up command after the G29 line you avoid that oozing

; Ender 3 Custom Start G-code
M104 S{material_print_temperature_layer_0} ; Set Extruder temperature
M140 S{material_bed_temperature_layer_0} ; Set Heat Bed temperature
G28 ; Home all axes
G29 ; BLTOUCH Mesh Generation
M190 S{material_bed_temperature_layer_0} ; Wait for Heat Bed temperature
M109 S{material_print_temperature_layer_0} ; Wait for Extruder temperature
G1 F1800 E-3 ; Retract filament 3 mm to prevent oozing
G92 E0 ; Reset Extruder
G1 Z5.0 F3000 ; Move Z Axis up little to prevent scratching of Heat Bed
G1 X0.1 Y20 Z0.3 F5000.0 ; Move to start position
G1 X0.1 Y200.0 Z0.3 F1500.0 E15 ; Draw the first line
G1 X0.4 Y200.0 Z0.3 F5000.0 ; Move to side a little
G1 X0.4 Y20 Z0.3 F1500.0 E30 ; Draw the second line
G92 E0 ; Reset Extruder
G1 Z5.0 F3000 ; Move Z Axis up little to prevent scratching of Heat Bed

The above code will activate the heating elements but starts homing and leveling procedure without waiting for the elements to get up to temperature. Only after the bed leveling is finished the printer will pause and wait for the heating elements reach the desired temperature.

This will prevent oozing on a cold start, but you will still be affected if you start a print right after another print, when the hot-end is still close to  melting temperature.

If you prefer to avoid that condition you might want to also move the M104 and M140 commands after the G29 bed leveling command.


Tevo Michelangelo nozzle below build plate?

Just move the Z-endstop up a little higher, also make sure the bed leveling screws are not completely screwed in.

So:

Move the head of the printer up.
Move up the Z-endstop so that the nozzle is a little higher than the build platform.
Home the printer.
Disable the stepper motors and move the head over the bed to a certain position (e.g. a corner without disturbing the Z axis), once you get to a new position of the bed, raise the bed by unscrewing the screws until a piece of paper shows noticeable drag when pulled between the nozzle and build platform.
Goto 3 until you have done all corners several times, also the center of the bed. It is advised to once in a while re-home the printer, this way accidental Z-axis movement is compensated again.


Do spare throats or a heater blocks ever break?

Short answer
Yes
Long answer
Heater bocks
A heater block is destroyed if one of the following happens

Threads stripped
Bent or otherwise deformed
stripped grub screw

All of these can happen by handling the block with too much force when securing nozzles, thermosensors or heater cartridges.
Throats
Throats can be destroyed, especially e3D v6 throats with their neck down on the center can be simply turned and broken in two. Lined throats can be heated too much and the liner destroyed, which not always can be replaced, mandating a spare part. And you can strip the threads.
Another chance to damage the throat is by using very hard material nozzles - stainless steel comes to mind. Such a nozzle would not deform itself like brass when tightened against the throat and might lead to damage to the end of the throat if exchanged several times.
Conclusion
If you run several printers or change nozzles regularly for whatever reason, it is a very good idea to have at least a complete set of spare parts on hand to fix problems that might occur during work on the printer. I have a fully assembled spare hotend waiting for its day to shine in case my current one breaks...


The issues you are facing can be caused typically by a defective X-axis endstop, an inverted logic of the X-axis endstop or a defective printer controller board.

When the X-axis endstop is reporting being triggered, it will not move. After "homing" it will only go to the right of the "home position".

There a couple of things to troubleshoot the X-axis endstop working:

Command an M119 command over a printer console or connect your printer over USB to a printer software application like PronterFace, OctoPrint, Repetier-Host, etc. and look at the reported endstop triggers; these should be triggered when the endstops are pressed. Issue the M119 when you press the X endstop manually, if it reports "open" for X you need to invert the logic. If still triggered, the endstop is broken.
Swap the X-endstop for a any other endstop (Y or Z); then you can also check if the printer board is broken!

If it is the case to invert the polarity of the endstop, in the Marlin firmware Configuration.h, look up:

// Mechanical endstop with COM to ground and NC to Signal uses "false" here (most common setup).
#define X_MIN_ENDSTOP_INVERTING false // set to true to invert the logic of the endstop.

Change the boolean value of the endstop you'd like to invert.


How can I best clean the print bed after a print?

If you are printing with ABS (or PLA), acetone will dissolve it.  Simply pour
some on the bed and wipe it off (beware, acetone can damage beds that have a coating or a plastic sheet over them, be sure to test this first).

Heating the bed back up may make the plastic softer and easier to
remove.

If you are using tape on the bed, you could remove the tape to remove
the plastic stuck to the tape.


As Fernando suggests, the problem is likely with your source file.  One easy way to verify this is to slice twice, rotating the STL by 90 degrees.  If both prints produce fat/thin sides in the same dimension on the print bed, then it's a printer problem.  If the fat side rotated with the STL orientation, then the STL is at fault.


Why don't 3D printer heads use ceramic inner walls?

It can be done cheaply, as two different users have proven, see

A practical 10 Cents Ceramic tube hotend, and;
Hotend with ceramic parts.

However, as Paulster2 states in his answer, there are some technical issues with using it, which make it rather problematic. Apparently, in comparison with PTFE, the thermal conductivity of the ceramic in spark plugs is too high, to use (according to nophead - a user on the reprap forums), and there are friction/clogging issues, unless the inner diameter is very well polished.

Synopsis of reference

The RepRap user, hp_, encountered the issues above when attempting a design - from Ceramic Hotend - Part 1

  Research

  As far as I know there are no ceramic hotends out there, I know
  nophead has tried some spark-plugs for nozzle holders but found them
  not suitable(thermal conductivity is pretty high). I wanted to give it
  a go, confident enough (I hoped), that it would work :)

  So in my case, a hotend exists out of 2 main parts, a nozzle holder
  and a nozzle.

  The nozzle is the easy part it would stay brass.
  The nozzle holder is the interesting part, here is what I've come-up with

  total length should be in the range of 35-40mm, see my first sketch
  below:

  here are many types of ceramic out there, ie. 95% AI2O3, 99% AI2O3,
  Zirconia (see material properties sheet Link)

  95% AI2O3 is easy to buy but after a few tests the conclusion was its
  to brittle for my taste, second material to try is Zirconia.

  I've found a few Chinese ceramic manufactures. Only draw back I had to
  order 10 pieces for the first batch.. on something that has never been
  tested, well I'd give it a shot.... and ordered the parts.

but the clogging issue mentioned above was encountered:

  ...after the first layer, it just stopped extruding.. ugh!!! what could
  be wrong????

  Possible root causes
  - Friction coefficient? Meaning after awhile the friction between PLA and the Ceramic became so high it would just jam the nozzle holder.

  Stickiness? Could it be that after awhile PLA would just stick to the Ceramic and would jam because of this?
  PLA thermal expansion( nozzle holder barrel is to small?) so the inner diameter of this nozzle holder is 3.2mm, could it be that the
  3.0mm filament would expand so much because of the heat, that it would start to jam the nozzle holder?
  Connection between nozzle and nozzle holder is insufficient cause the Jam??

The user was forced to return to using PTFE.

From Ceramic hotend part-2, after some rework done by the Chinese manufacturer, the new hotends worked correctly:

  Awhile ago i stared working on the ceramic hotend and found out the
  first version wouldn't work for 3.0mm fillament,

  after some discussion with my chinese counterpart :) i got a new
  version of the ceramic piece.

  They polished the inside very deep and precise. and i gave it another
  go.

and

  some more tinkering with the hotend and a new nozzle design, with a smaller Inner diameter, and its longer

Apart from that the details are a little sparse.

Additional information

From J-head with ceramic body instead of PEEK, specifically this post:

    Just to be clear, it's Ceramic Zirconium.

    My concern was that Zirconium becomes brittle when it is exposed to heat for consecutive long periods of time. I would stay with PEEK.

  MgO or Yttria stabilized grades of Zirconium are very stable.

  Pure ZrO2 is known to crack, so additives are used to stabilize it.

  Key Properties of Zirconium Oxide

  Use temperatures up to 2400°C
  High density
  Low thermal conductivity (20% that of alumina)
  Chemical inertness
  Resistance to molten metals
  Ionic electrical conduction
  Wear resistance
  High fracture toughness
  High hardness

  Typical Uses of ZrO2

  Precision ball valve balls and seats
  High density ball and pebble mill grinding media
  Rollers and guides for metal tube forming
  Thread and wire guides
  Hot metal extrusion dies
  Deep well down-hole valves and seats  -Powder compacting dies
  Marine pump seals and shaft guides
  Oxygen sensors
  High temperature induction furnace susceptors
  Fuel cell membranes
  Electric furnace heaters over 2000°C in oxidizing atmospheres

  Zirconium oxide

  Zirconium oxide is used due to its polymorphism. It exists in three
  phases: monoclinic, tetragonal, and cubic. Cooling to the monoclinic
  phase after sintering causes a large volume change, which often causes
  stress fractures in pure zirconia. Additives such as magnesium,
  calcium and yttrium are utilized in the manufacture of the knife
  material to stabilize the high-temperature phases and minimize this
  volume change. The highest strength and toughness is produced by the
  addition of 3 mol% yttrium oxide yielding partially stabilized
  zirconia. This material consists of a mixture of tetragonal and cubic
  phases with a bending strength of nearly 1200 MPa. Small cracks allow
  phase transformations to occur, which essentially close the cracks and
  prevent catastrophic failure, resulting in a relatively tough ceramic
  material, sometimes known as TTZ (transformation toughened zirconia).

  Zirconium dioxide is one of the most studied ceramic materials. Pure
  ZrO2 has a monoclinic crystal structure at room temperature and
  transitions to tetragonal and cubic at increasing temperatures. The
  volume expansion caused by the cubic to tetragonal to monoclinic
  transformation induces very large stresses, and will cause pure ZrO2
  to crack upon cooling from high temperatures. Several different oxides
  are added to zirconia to stabilize the tetragonal and/or cubic phases:
  magnesium oxide (MgO), yttrium oxide, (Y2O3), calcium oxide (CaO), and
  cerium(III) oxide (Ce2O3), amongst others.

  In the late 1980s, ceramic engineers learned to stabilize the
  tetragonal form at room temperature by adding small amounts (3–8
  mass%) of calcium and later yttrium or cerium. Although stabilized at
  room temperature, the tetragonal form is “metastable,” meaning that
  trapped energy exists within the material to drive it back to the
  monoclinic state. The highly localized stress ahead of a propagating
  crack is sufficient to trigger grains of ceramic to transform in the
  vicinity of that crack tip. In this case, the 4.4% volume increase
  becomes beneficial, essentially squeezing the crack closed (i.e.,
  transformation decreases the local stress intensity).

and the following post

  Thermal conductivity:

  Diamond thermal conductivity: 1000 W/(m·K).
  Copper thermal conductivity: 385 to 401 W/(m·K).
  Aluminum: 205 W/(m·K).
  Stainless steel 16 W/(m·K).
  Granite: 1.7 to 4 W/(m·K).
  Zirconia has a typical thermal conductivity of 1.7 to 2.2 W/(m·K).
  Porcelain has a typical thermal conductivity of 1.5 to 5 W/(m·K).
  Glass thermal conductivity: 1.05 W/(m·K).

Rulon

As an aside, again from J-head with ceramic body instead of PEEK, specifically this post:

  Rulon was one material we used. I think it is a glass filled ptfe. The mechanical strength is far better than solid ptfe and it is easy to machine. There are many grades but Rulon AR for example will withstand 288 deg C.

but there are inconsistencies in quality

  Rulon i looked at a while ago, there are plenty of options with it, however the cost of some of these materials can be incredibly high, and in some cases availability is a serious problem, and the difference country to country is borderline criminal in some cases


Run custom code between g-code commands?

A solution I use involves a 3d print server. I have defined shell scripts that address the GPIO ports of the Raspberry Pi that runs OctoPrint. OctoPrint is a 3d print server that can be accessed over your home network.

From the OctoPrint homepage:

  OctoPrint is the snappy web interface for your 3D printer that allows
  you to control and monitor all aspects of your printer and print jobs,
  right from your browser.

This print server application allows for specification of custom Gcode commands (linked to system commands for instance; note this is a plug-in called "GCODE Systems Commands", see image below).

As an example, e.g. OCTO100 is scheduled to run fan_on.sh shell script. This script in its turn drives a relay to switch the annoying extruder cooling fan that is always on when the printer is powered. These codes can then be used throughout your sliced file to do stuff you want (e.g. by using the TweakAtZ plugin of Cura). E.g. my extruder fan will stay on several minutes before it is scheduled off after a successful print through OCTO110 which in itself runs the script fan_off.sh.

The scripts from the figure could be setup to schedule to do something, e.g. fan_on.sh controls a relay using port 22 of the GPIO of the Raspberry PI:

#!/bin/bash
gpio export 22 out
gpio -g write 22 0

So to disable the fan you would need fan_off.sh to be:

#!/bin/bash
gpio export 22 out
gpio -g write 22 1


Why are the STL files for the Ultrascope telescope at 45 degree angle?

The orientation of the part in the STL file depends on the Software that creates the file. I had a software that would export the parts standing upright instead of laying flat. Depending on the CAD software it can be beneficial for the creator of the model to create in in a different orientation as the one you want to use for printing. Also not all CAD Engineers know (or care) about the best orientation for printing a part.

So my guess is that this is an issue of file export/ STL file creation.

It is totally normal to rotate the parts into a position that is best for printing.


A quick blast from a heat gun will very slightly reflow the surface texture and eliminate white marks.

However, it's important to avoid over-heating the perimeter layers or you'll see them soften and sag into the infill. So wait for the heat gun to get fully hot and then use a short duration of high heat. Let the part cool between attempts if you don't get it all the first time, or need to clean up a large area.

Incidentally, the heat gun will also help clean up strings from travel moves.


Laser SLS printers (3D Metal Printer) software requirements are very similar to SLA printers specially laser ones.

There are lots of different tools which you can use together.

You can use Lasershark 3D together with creationworkshop.

Also you can convert your source file to SVG or image files, using Slic3r, nanoDLP SLC2PNG or Asiga Stomp/Sleece. And convert SVG or Image files to toolpaths using cad.py, gcodeplot or any other freely available softwares.


Centering model with CuraEngine when creating g-code?

Found a solution.
This need to be applied under "settings"

"command_line_settings": {
    "label": "Command Line Settings",
    "description": "Settings which are only used if CuraEngine isn't called from the Cura frontend.",
    "type": "category",
    "enabled": true,
    "children": {
        "center_object": {
        "description": "Whether to center the object on the middle of the build platform (0,0), instead of using the coordinate system in which the object was saved.",
            "type": "bool",
            "label": "Center object",
            "default_value": true,
            "enabled": true
        }
    }
}


How do people load filament, prime the printhead, flush out the old filament when changing colors when using a standalone 3D printer?

My printer (IdeaWerk 150) is very basic and doesn't have any options for this from the screen.

I wrote a really simple GCODE file that brings the nozzle up to temperature, then runs the extruder for a few seconds, then waits, then extrudes for a bit again. I think it does this 3 or 4 times then stops. I can put the file (when converted to .x3g!) onto an SD card and run it whenever I need it.

I have a similar file that allows me to level the bed without a computer by just moving the nozzle around to a few key points on the bed and pausing for a few seconds.

I used a GCODE file generated by my slicer in verbose mode to get started, along with a list of codes

I don't have these files to hand at the moment, but this is my start.gcode:

(**** beginning of start.txt ****)
(This file is for a WeisTek IdeaWerk 150)
(**** begin initilization commands ****)
G21 (Metric FTW)
G90 (Absolute Positioning)
M18 (This disables the stepper motors.)

G92 X0 Y0 Z0 A0 B0 (Declare the current position to be 0,0,0,0,0)
(**** end initilization commands ****)

(**** begin homing ****)
G161 Y X F2500
G92 X0 Y0 Z0 A0 B0
G1 X5.0 Y5.0 Z-5.0 F450
G162 Z F450
G161 Y X F2500 (Home X axis maximum, go until reaching the end stop.)

G92 Z142.4 ( ** Set Bed Height ** )

G92 X-75 Y-75 (set zero for X and Y)
(**** end homing ****)

M108 R8.0 (Extruder speed = max)
M6 T0 (wait for toolhead parts, nozzle, HBP, etc., to reach temperature)

G1 Z10 F500 (Bring bed up)

M101 (Turn on Extruder)
G04 P8000 (Wait for 8 seconds for flow)
(**** end of start.txt ****)

If I feed just this file into my printer, it will heat up the nozzle, bring the bed up to about 10cm below printing height and once the nozzle is at temperature, it turns on the extruder for 8 seconds.

Your printer will likely be different to mine - there are a few different flavours of GCODE and you will likely have different XYZ positions, so take a look at some GCODE generated by your own slicer and identify the different parts. The principle is the same.


The problem with using a release agent is, you really run the risk of the print not sticking to the bed at all. Sticking to the bed is uber important, because if it's not there, the piece isn't going to come out right. Having it stick to the bed is a good thing (something which I struggled with for a while!!).

I believe what most people do to get the piece unstuck from the bed is to use a putty knife. Wedge the flat part under the piece and twist slightly. Continue doing this around the print until you can get it to release. Your best bet is being careful by going easy with it though. Also, if the print is sticking well to the bed, ensure you're not using a raft. This will make it even more difficult.


Enclosed volumes with stereolithography 3D printers

The bubble will contain air, but this will vary by printer. Most resin printers lift the printed part out of the bath slightly after each layer. Some printers, however, don't lift the piece completely out of the bath. This will cause the resin to become entrapped. Once those entrapped pockets of resin are exposed to light, they will also undergo photopolymerization. It may be possible however to program those printers to lift the part completely out of the resin for each layer.


Diagnosing why the left side of a print detaches from the board

The uneven level is explained by the unfortunate choice of the printer manufacturer to not have a second Z lead screw. It is pretty difficult to level these printers, it is all a combination of the correct X belt tension and roller tension. The uneven level in the first picture is what is causing your print to detach, As can be seen you've got a lot of "squish" on the right side, but less adhesion (seen by the less transparent color) on the left, therefore it would fail on the left.

You need to:

level better,
fix the skew XZ gantry or
use an adhesive (and/or a brim).

Please note that the level of the table top has nothing to do with the leveling of the printer, nor with the leaning of your prints. You're just having adhesion problems as a result of an uneven bed/gantry.


The filament is almost impossible to remove

This usually happens when your nozzle is too close to bed during the first layer.
  Quick fix is redo bed levelling.
  Clean your build surface.
Watch you first layer


Nozzle cleaning tool broken inside nozzle

Your best fix is to get a replacement nozzle. Nozzles are relatively cheap. Having and replacing them on a regular basis is a good thing. Replacement can help you maintain proper printing. You can probably get the cleaning tool out of the old nozzle, but most likely you'll damage it further, making it nearly useless.


The Anet A6 uses the mk8 extruder (also used by the Anet A8). Please search for mk8 nozzles (for 1.75 mm filament). These nozzles use M6 threads. Standard nozzle size is 0.4 mm.


Extruder skipping/clicking (brand new printer)

First you have to see if nothing jams the filament (blocked nozzle or anything in its path, PTFE tube not good, etc).

Second, the temp for ABS is about 225°C to 230°C. At least that worked for me.

If none of the above, then go for the motor. The problem could be from bad settings, low power or a motor malfunction. Maybe the motor is no good to begin with.

Good luck !!!


This could be caused by under extrusion, often caused by the bed being too close to the hot end / extruder nozzle. You could try to relevel the bed, or change the screws so that the bed moves down slightly. Often when levelling, you want to feel slight resistance when sliding a piece of paper between the bed an the nozzle. You should do this for all 4 corners. Be careful though, you dont want the bed too far away from the nozzle, or problems maybe arise with the print not sticking to the bed.

Hope this helps, Luke.


Robotdigg linear guide not smooth motion

Difficult to say with the given data, but here are a couple of ideas:
First theory:

The belt is too thin/flexible for the linear guide.

Linear guides remove the backslash by adding quite some pressure in the ball system: The block is slightly too small (compared to the rail) and thus it compress the balls and rail. The backslash is avoided until you reach this force.
This pressure require a little bit of force to move the block along the rail, so if your belt is too thin or flexible, the belt will start to move until the elasticity of the belt reach the force required to move the block, then the block move a little bit and stop again.
In a fast movement, your block never get to stop, while in a slow movement, it has time to start and stop. Maybe what you feel like "not a smooth movement"
If you identify this case, I suggest you the following solutions:

Lubricate correctly the guide, this could be enough to reduce the issue to an acceptable level.
Change the belt to a larger one, with fibre glass inside (not only rubber).
If I am correct, the "H" of your MGN12H stand for the pressure of the block. H is for high pressure, switching to a C is far enough for a 3D printer and will reduce the drag.

Second theory: (Thanks to FernandoBaltazar)

You got some dust, rust inside

Remove the belt and move the block with the hand, if you are able to feel the movement is not smooth, then it's probably this case.

Add some grease (Never in your life use cooking oil)
Clean the dust of the rail and exterior of the block
Move the block from one side to the other of the rail until the movement become smooth.


What is stopping us from mixing 3D filament colors in an Extruder?

I just started with google and phrase "3d printing color mixing" and on the first place (in fact first two were valueless adverts) I got this Instructables - DIY Full Color Mixing 3D Printer.

How it works?

It uses magenta / cyan / yellow filaments and mixes it while printing with Diamond hotend.

It definitely does what you are asking for and it's exactly the same idea you come up with ;)

Overview

  Getting the controller board ready for three extruders... I hacked
  a RAMBo board to drive three extruders, however, you can use any board
  you want... (most people use a RUMBA due to it having all the
  pins/components needed for 3 extruders native on the board)
  Rewriting Repetier firmware to get color mixing working on your
  machine.
  How to install, configure, and use the diamond hotend - tips /
  tricks / lessons learned / etc...
  My original Bowden extruder design and various ways to mount the
  three extruders for your set-up
  My universal magnetic effector plate and accompanying hotend mounts
  for quickly swapping various hotends. (delta specific)
  How to design multi-color models and making STLs that can be
  exported and used as a individual STLs or combining them into an AMF
  file for slicing...
  Configuring color mixing in Repetier and Slic3r to print above
  mentioned multi-color models.
  Anything else I can think of later that I can't think of now.
  Comprehensive overview of Quantum Mechanical Entanglement as it
  pertains to multi-color printing (just kidding, I don't understand
  that... But I will cover multi-color printing throughly)


Auto leveling with Marlin and RAMPS 1.4 does not work

Bed leveling is disabled by default. So the mesh was scanned but is not apllied after G29 command. To apply the mesh we need to enable bed leveling using

M420 S1

command


Stepper motor moving only to one side after reset

Assuming that your M119 command has been executed for non-depressed endstop switches, it could be concluded tht the firmware is incorrectly configured.

If you execute the M119 G-code command and get TRIGGERED status values for endstops, even when the nozzle head is not pressing the endstop switches, then you have incorrectly configured the endstops in the Marlin configuration.h file.
The most common setup is to have the COM go to ground and NC to Signal, this requires the following values to be false, otherwise you need to use true.
#define X_MIN_ENDSTOP_INVERTING true// Set to true to invert the logic of the endstop.
#define Y_MIN_ENDSTOP_INVERTING true// Set to true to invert the logic of the endstop.

When an endstop is reported to be triggered while the switch is not depressed, the logic needs to be reversed. Marlin firmware will only allow movement to go away from the endstop when it is triggered, never against a triggered endstop (as this might damage the printer).


Where is the auto-reset jumper on the Wanhao i3 PLUS?

The pictures don't help much, and I don't know the board. But if it is as described here, Elec Freaks Wiki - RAMPS Melzi, then you need to look for the FTDI Chip FT232. The reset is caused by the DTR Signal. There needs to be a copper trace from pin 2 to the capacitor and then to the jumper. From the jumper a trace leads to pin 4 of the Atmel ATmega.

If it is a clone, the jumper might have been "optimized away". If so, desoldering the capacitor gives the same result.  Be certain to desolder the right one. If unsure keep the capacitor and solder it back in if it was the wrong one.


How can I extend silicon hotbed wires safely?

750 W at 120 V is 6.3 A. 22-24 AWG is on the thin side for this. I would recommend 18 AWG or thicker. You don't need a specific style of insulation for this (other than something that is rated for the voltage and temperature the wire will need to withstand, but most commonly found wire should be good).

A good way of connecting the wires would be to solder them. If you do not want to solder, there are many products on the market for connecting wires. A butt connector that you crimp could be a good option, or you could use a WAGO clamp. Whatever option you end up using, be sure to provide adequate strain relief as the connection point (be it soldered or with a connector) is more likely to fail from fatigue.


That it triggers when the nozzle is about 1 mm from the build plate is how it is supposed to work. The installation manual describes how to setup the sensor.

  The mount needs to be adjustable so that the distance between the bottom of the sensor (not the pin) needs to be 8.3mm above the tip of the nozzle.

When taking the above distance into account, the probe should be hitting the build plate first when it is extended. When the probe triggers, it triggers at a certain distance from the nozzle. It is this distance that you need to add as an offset so that the printer knows where the actual Z=0 is. To determine the offset, you home the printer, then lower the head until a piece of paper gives a little drag when pulled under the nozzle. From the display you can read the offset, e.g. -1.4. With command M851 Z-1.4 you set the offset between level and trigger point. Use M500 to store the new settings.


Ender 3 print is skipping and dragging up base print lines

So, contrary to what people were saying, my problem came from my spring that controlled filament flow. There was too much tension and it caused motor skipping. I did get rid of the overlap with the blue tape, but otherwise I had to clamp down my spring and that fixed the issue.


How to connect a Geeetech Prusa I3 Pro B to Repetier-Host on mac

This is not a direct answer to your question, but a solution for your problem.

If a motor is running in reverse, there are at least 2 solutions. You can reverse the connector of the leads to the stepper, or flash new firmware where you reverse the stepper in the configuration file.

The most effective and fast solution is to reverse the connector of rearrange the wires in the connector.


Fusion 360 will do finite element analysis (simulation), although I haven't used it. Whether it will perform the type of analysis that you are looking for, I do not know. Check Autodesk's tutorials.

One problem that you will encounter is that items printed using FDM technology are highly anisotropic. In other words, they have a grain, and are stronger/weaker in some directions than in others. I do not think that Fusion 360 can take account of that in its analysis.

Autodesk: Fusion 360


Z-min always open when using BLtouch and Marlin 2.0

In order to use a BLTouch probe (or clone probe) you need to configure the firmware to know that a servo operated Z endstop is being used.
From the referenced files that are used for building the firmware you are running can be found in the configuration.h that:
/**
 * The BLTouch probe uses a Hall effect sensor and emulates a servo.
 */
//#define BLTOUCH

When using a servo port operated probe (position of the servo corresponds to a certain action) such as the BLTouch, 3DTouch, etc. you need to configure using it as such:
/**
 * The BLTouch probe uses a Hall effect sensor and emulates a servo.
 */
#define BLTOUCH

Furthermore, you need to be sure to connect the cables of the touch probe according to the pin arrangement as defined for you controller board.
E.g. #define Z_MIN_PROBE_USES_Z_MIN_ENDSTOP_PIN could be used to re-use the Z-min endstop connector on the board.

Note that when using a touch probe (which is a sophisticated sensor with it's own onboardmicro-processor with dedicated firmware), you cannot use M119, the endstop status from the touch sensor cannot be read from the output of the command. According to "Marlin documentation", The BLTOUCH probe only sends a brief pulse, so “TRIGGERED” indicates the probe is in error state..


You could modify it as shown in my picture.  I added lines tangent to the 11mm circle and in this example I set them to a 40 degree overhang which should be fine, the top line is also tangent to the circle and in my experience it's easier to bridge a small section rather than do a bunch of small overhangs like an arc would do.  You still end up with quite a bit of contact but also easy to print.

I did something similar to this on my printer where the smooth rods enter horizontal holes.


By avoiding pin 3 entirely, the Z-axis steppers have started to move correctly. My bed heater went out a while ago, so I redefined the connections in Marlin to use that pin (pin 12) as the Z-step pin, connecting it to the A4988 accordingly. This has caused no issues other than small noise problems so far. Unfortunately, I can't speak to any potential issues pin 3 may have had to cause this behavior, all I have is this one potential solution.


This is relatively easy to do in any CAD/mesh software.  For example, if you load import the model into Meshmixer, you can select a given solid and N links of chain connected to it (using "expand selection to groups" or similar to be safe). Then use the "Separate" command to allow you to move/rotate that subset on its own. All you have to do is make sure the two chain links at the point of rotation remain disjunct.
Once you've moved everything around, just SelectAll and export.


Are there attempts to standardize G-code for FFF/FDM printers?

G-Code Is RS-274/NGC
There is no need to attempt to standardize G-Code, the G-code itself already is standardized: it is the NIST RS274/NGC, or often short AIN RS-274 and was not designed for just FDM printers but any moving tool. Power lathes, CNC and laser cutters all can run on RS-274! G0 and G1 always move, G28 is always the homing procedure and so on. To show how the RS-274 standard evolved over time, check out an older variant of the document, the NISTIR 597 Canonical Machining Commands.
Implementation is not standardized!
However, due to the design of a given machine, the exact procedure for these commands has to be different for different designs. For example in a carthesian, prusa style printer Homing is usually moving negatively in X, Y and Z, in that order, one after another. But in a Delta Printer, that would most likely get your printhead to an illegal position: the printhead would first be moved out of the print volume and then never hit any endstop as those are mounted at the top of the printer. Instead, all axis on a delta are moving up simultaneous on homing, stopping each axis as they hit their endstop at the top, then the whole setup moves down to the printbed in unison. On a mill, lathe or router, the G28 operation usually starts by backing the tool away from the work volume, then moving to the 0 and only then moving the tool back into the work area to avoid fixtures.
G & M-command gaps
Another caveat is, that the standardization via the NIST document only encompasses codes G0 to G99 and M0 to M49 - with gaps. Which brings us to the code block M - Miscellaneous. It is not fully defined in the document. FANUC setup uses a few more common M-commands but might contain more. The CNCcookbook has only 16 common M-commands, none of them a reporting one. Autodesk declares even only 11 M-block commands most common: M0 to M9 and M30. Of these the coolant related ones are usually irrelevant for FDM.
M115
M115 and M503 are reporting functions outside of the areas that were pretty much defined by the norming agency and thus have cropped up as development needed them until they formed undefined de-facto industry standards. This means that the standard itself does not contain them, but everybody and bob know that these commands are meant to report firmware and report settings respectively because some popular machines started with it.
These two commands are to inform a programmer what is the brains of the machine and settings, and as such, they are also subject to the style guide of the programming institution - the norm document does not contain a style guide, leaving it free for any implementation to chose style. A working example is Marlin's M115.
However, there are reasons why a programmer might disable M115 but keep M503: Industrial machines, especially such with maintenance contracts, usually don't allow users to access the firmware in some ways to on one hand keep them out from messing with the machine too much and on the other make sure that only a licensed technician can access some reporting functions by using proprietary commands. M503 on the other hand reports on the current status of settings that might be changed by the user or their service technician to account for different print requirements.


I redid the print in order to reply to some questions posed in the answer of @kdtop. The print started but the output was not consistent and sometimes stopped. The temperature is 195°C and sometimes 'drop' to 194°C. First I pushed the new real so that the extruder did not need to pull so much. When this did not solve the problem I changed the temperature to 200°C. Now the output became consistent and my print finished. It was not as good as the one that I did with my previous filament. The top was not as neatly closed. Only the last 2 layers covered more or less for 100% the surface (perhaps 200°C is too high for this?).

For me the solution is to higher the temperature to 200°C (or perhaps 205°C).


Home E / extrude until endstop is triggered

You should be able to adapt the "Dual X Carriage" feature for your project.

That allows a second print head (on the X axis) to move independently of the "main" X axis motor - and it can also be homed against its own endstop.

You can enable this feature in the configuration_adv.h file under "Dual X Carriage".

By default, all "Dual X/Y/Z axis" features use the first free extruder stepper driver - which would be E1 in your case.

You would have to adjust the X2 parameters to allow you to zero the motor on the endstop (X2_MIN_POS 0, X2_HOME_DIR -1, X2_HOME_POS X2_MIN_POS), as well as setting the default mode to "FULL CONTROL" (DEFAULT_DUAL_X_CARRIAGE_MODE DXC_FULL_CONTROL_MODE).

As far as I understand, you can then use
T0 and T1 to change between both "X axes", with T0 selecting your real X axis, and T1 your custom stepper motor.


Recommendation for free, intuitive offline 3D modeling software for 3D printing

I suspect there may be fewer answers than we expect.
Personally free software wise I like FreeCAD but it is not similar to the simple shapes of tinkercad at all and not intuitive.
I did know someone who used something from https://www.xyzprinting.com that was very similar to the tinkercad stuff, but eventually ran into limitations and switched to more advanced software anyway.


Positioning Extruders after Tool change : Marlin 1.1.6

Interesting project your are working on.

  Does it work with normal dual extruders.?(Does mine come under any two
  system mentioned above?)

The hotend/extruder you mentioned above is a E3D Chimera like system. And it is not suited for your application because you cannot lower/lift the hotends independently from each other.

examples of these configurations

DUAL_X_CARRIAGE:

look at BCN3D sigmax dual extruder

SWITCHING_NOZZLE:

look at ultimaker 3 mechanism for lowering/switching the active hotend.

The above systems aren't well documentend and will be hard to make.
I advice you to look into an interesting blog post from E3D about a tool changer. It is opensource, well documented so you're be able to create one yourself with tool heads for your application. A spade to create patterns in the powder. And a liquid tool to fill the patterns.


Reboots happen in 2 cases on a printer:

If the board power has been below a the operational threshold (~3 V) and the capacitors on the board are empty, the power dip can result in a reboot.
If a device connects to the serial-USB port, it reboots.

If you power up the printer not connected to any other device, it should run continuously. If it flickers and reboots, the power-lines to the board or the PSU are bad. Check those in reverse.
If it only reboots again and again when connected to a serial port (PC, Octoprint etc), your problem is the cable - it might be jiggling or be defective, or otherwise de- and re-connect again and again.


Unlike PLA, PETG does not like to be "squidged" down, it likes to be laid down. If you use too small a layer height, there is the danger of the filament sticking to the nozzle, rather than the bed (or filament already laid down). Try using a larger layer height -- between 0.2mm and 0.3mm, if you have a 0.4mm nozzle.


You may be getting shrinking due to cooling on the non-top and non-bottom layers. Sixty percent infill is rather substantial. I'm printing 20 hour pieces in ABS at 100 °C / 250 °C using ten percent infill and getting nothing like what your image shows.
Can you do with a lower infill? More isn't always stronger. Four perimeter shells may be a factor but you'll probably see a difference with a smaller percentage infill.


Printed part problem, distortion on upper section containing hole

It appears that the upper part of your print contains less plastic than the lower. This would mean that as the printer begins to operate in that area, the previously deposited plastic has less time to cool.

The distortions are difficult to see from the distortions of the photograph, but I've experienced similar upper, smaller section failures.

You could consider to print more than one copy of the item on the bed, which will require the nozzle to move away from each layer, allowing more cooling time, or add a throw-away model.

I've also added an ooze shield using Simplify3D to create a single wall around the part, providing the same cooling time concept.

If you try these options and still experience a problem, please consider editing your post with material used (PLA, ABS, PETG, etc) as well as temperatures and speeds used for this print.

Your slicer is not likely the problem, but is often useful information. Printer name is sometimes helpful, but I think it's not critical in this circumstance.

It's also useful to orient the part in the photograph to match that of the print. It's apparent in this case that the top of the print is to the right and bottom is to the left. If that is not correct, please advise in edit.


If you power the printer and it starts heating up the hotend, it most probably is caused by a faulty controller board. More specific, the MOSFET (as in an electronic switch component) controlling the current to the heater element is causing this. MOSFET devices usually fail short-circuit implying that when the MOSFET has failed, the current can freely run to the heater element without being controlled by the board.
If you are handy with electronics, you can replace the MOSFET, but it might be better to upgrade to a newer controller board as there may be other damage as well.


Any fix for PLA prints getting more brittle over time?

PLA absorbs moisture, so keeping the filament dry is a key factor. Aside from that, PLA is naturally more brittle than other plastics like ABS and Nylon Sorry, tried to find a graph to prove it, but couldn't find one.

There's a good Google Group discussion and many other resources that go over good storage habits, but as for fixing the existing filament.

Try the following:

Place PLA in an enclosure (plastic bin, Zip-loc bag, etc.)
If you have some, add some moisture absorber(s)
Place the tub in a warm environment (naturally or artificially) and make sure the area is dry as possible (not in the shed in the back, by the woods...). Possibly next to a heater vent or space heater in your house?

Essentially, you're trying to treat the material. When the material goes through a heat treatment (aka the heat block in the extruder), the mechanical properties are beginning to change. The brittleness can be set by how quickly the material cools. I'm speculating that the moisture does any of the following:

Keeps the filament from heating up to the desired extrusion temperature.
Burns the filament.
The moisture is evaporated, leaving gaps in the extruded filament (under microscope).

I looked into this a few years ago and have forgotten most of what I found out, but I'll keep looking and update my answer here.


Is there a table or list of tare weights of empty spools of various manufacturers?

Yes, there is a table on Reddit - Empty spool weights for estimating remaining filament which suggests that the norm (in 2015) was between 170 and 330 grams for a 1 kg spool, superficially in a bimodal distribution clustered around the high and low points. Presumably these were for 3 mm filament, this post dating to before the popularity of 1.75 mm...

Manufacturer's have an incentive to reduce the mass of their spools, or even ship without spools, since the shipping cost will eat into their profit margin.


What should I use to clean buildtak(knock off)?

Isopropyl alcohol (IPA) is the general recommendation I've heard and it works well for me.


The solvents that can dissolve PET are pretty nasty -- I wouldn't personally handle any of them outside a lab fume hood. If you have that, a 50/50 mix of MEK and methylene chloride should work. (Increase MEK ratio if you want faster adhesion / less working time, and vice versa.)

First thing I would try is printing directly onto the (super clean) glass. Print the first layer at high temp to try to get a good bond. Then over-extrude to get watertight perimeters. It MIGHT be better to print on a cold bed to keep the PET from popping off when the glass cools, but you would need to do some experimenting.

You could also try heating the slide to the melting temp of PET on a hot plate and then attaching the printed part.

Failing that, a transparent superglue could be a good approach.


How can I improve the overhang angles my printer can successfully print?

The two most important things you can do are:

Provide adequate cooling to solidify the plastic quickly
Minimize layer height

Cooling is really obvious. You need the plastic to solidify before it has a chance to sag. PLA in particular has to shed a lot of heat before it is fully solid. A fan and air guide setup using a "squirrel-cage" radial blower around the nozzle is optimal. A little 30mm or 40mm axial fan will not provide optimal performance.

Low layer height when slicing is less obvious, but is extremely effective. When you use thinner layers, two things happen:

There is less melted plastic per pass and a higher surface area to volume ratio, so the fresh material cools faster.
A larger percentage of each strand in the overhang is supported by the previous strand. If you do 0.2mm thick by 0.4mm wide, half of each strand is unsupported. But if you do 0.1mm thick by 0.4mm wide, only a quarter of each strand is unsupported.

When you combine these two effects, it is possible to exceed 70 degree overhangs with good surface quality.

Another lesser factor is printing shells/perimeters inside-out rather than outside-in. This helps anchor the outermost strand a little better as the overhang is built. This is pretty minor though.


What is the best material for printing an anatomic bone model?

The Stack Exchange discourages "best" type questions, as any answers are going to be opinion based. There are going to be more opinions than types of materials and types of printing.

Your question regarding specifics is more on the mark, however, and has less to do with material than with method.

Consider that resin based printing, especially SLA printers will provide extremely fine detail at extremely fine prices. SLA printers are more commonly used for smaller models such as jewelry and dental applications.

SLS, Selective Laser Sintering is capable of nearly as detailed work as SLA and is better suited for larger models. One can contract for SLS work on the major 3D printing services. Pricing for SLS is also "up there." Use The Google to locate 3D printer services for a suitable resource.

In the FDM world, you'll find lower costs and lower resolution. My printer is capable of 0.100 mm layer thickness, which means barely visible layer lines, but they are still quite obvious, especially on sloped or slanted surfaces.

I suggest that you find a small scale or segment of the part you wish to have printed and send it off for sample returns in the above formats.

As an option, once you have the parts, you could consider to use them to create molds and cast in resin as many copies as you would need.


Is this what you're looking for?
(https://the3dprinterbee.com/how-does-a-resin-3d-printer-work-sla-dlp-lcd-explained/)
Material Beam
Material blasting is a unique 3D resin printing technology that can be compared to an office inkjet printer. It is also considered one of the fastest and most accurate 3D printing technologies available for resin printing today.
Material Beam 3D printers are similar to inkjet 3D printers in that they also have a print head from which thousands of tiny resin droplets are applied to the building platform and then cured with UV light. Once a layer has been completed, the building platform automatically lowers to the height of a layer and the process is repeated until the object is completed.
The technology of material blasting enables high dimensional accuracy, but speed is also a convincing point. The process in which the resin droplets are ejected from several print heads, which in turn move back and forth over the building platform, is known as line-by-line cutting. This ensures that multiple parts can be produced without affecting the build speed. As a user, you also have the choice between matte and shiny surfaces on your 3D printed object. However, the individual components for material beam technology are very cost-intensive. Other disadvantages are the waste of material when you choose to print matt surfaces and the low strength of the 3D printed parts.


Connecting disconnected pieces in Fusion360 Stencil. Sketch entire model then extrude

As I see it, for a stencil you want the brown part with the white part(s) cut out.

This is easily doable. You can do this one sketch at a time, extrude it, and cut it out of the brown part.

To connect the inner brown parts to the rest of the brown, you'll need to cut a thin rectangle in the white character so that the inner brown pieces are connected to the outer brown pieces.


If you've looked into using Blender, you would have discovered that that program is free. It is also one of the better suited programs available for the task you've selected.

It's possible that your search terms may not have provided the best results for your objective. The task you describe is known as UV mapping, also known as adding texture to mesh, adding texture to a model. The generic term "texture" can be confused, as many people would consider texture to be the feel of a surface. Rough, smooth, slippery, etc., do not apply here.

Texture in the 3D modeling world applies to a surface description specific to visibility. In your task, texture refers directly to color.

Consider to search using the above terms or follow this lead:
Add texture to model Blender

Doing so provided a few quite well written links. One of the first to appear is an Instructable.

The above Instructable also links to a video, which is also a good location for learning basics for Blender and texturing models.

The above search also results in finding an SE entry directly related to Blender:
StackExchange Blender texture Q/A

Consider that you can create a flat image using your preferred graphics editor, placing shapes and colors as needed and then "project" or paste or plaster or project that image on the surface of the model in a controlled manner. This would be easier and faster than attempting to color manually individual triangles of the model's mesh. The SE link summarizes this process, although additional research is indicated.

Practice with Blender on simplified models and you should be able to grasp the necessary skills in short order.


How to fight lots of stringing with PLA at low temperature (185 °C)?

4.5 mm is a low retraction distance. Cura's default is 6.5 mm, and the Ender 3 profile provided with Cura sets it to 6 mm. The first thing you should try is increasing the retraction amount up to at least 6 mm. Also, make sure you actually enabled retraction. I saw one question here where a Cura user had enabled "Retract at layer change", which does not enable retraction (but of course it shows the options like retraction amount since you need to be able to select it for this too).

Your low nozzle temperature of 185 °C is also a problem. You'll have very low flow at that temperature, resulting in under-extrusion and pressure building up in the nozzle instead of extruding the material. That in turn will make it so, even after retracting, there's still material (and pressure) at the nozzle and it will keep oozing, unless you set a really high retraction amount (and even then problems will build up over time during the print, but you might get lucky and not see them). The only way to print PLA at 185 °C is really, really slowly.

In general, some people would also recommend trying a different filament, based on reports that some vendors' PLA oozes and strings badly, but I don't think that's an issue for you. I use Hatchbox filament on my Ender 3 all the time and never have a problem with stringing from it. And even if the filament is prone to stringing, you can almost surely avoid it with proper settings. Even very soft flex filaments can be printed on this printer without stringing as long as your retraction, temperature, and speed are tuned to avoid having pressure at the nozzle during travel moves.


Printing 2x slower after upgrading to "MarlinTarantula" firmware

First, Ultimaker Cura estimated printing times are not necessarily accurate for non Ultimaker printers. For Ultimaker printers this is perfectly tuned, Cura estimates the printing times from experience for the UM3E correctly. Please look into question "How to determine real printing speed (tarantula/cura)?" which is relevant to this question and has an interesting accepted answer.

Second, changing the MAX accelerations will not work, you should increase the default acceleration:

From the TEVO Tarantula Marlin fork you read from the Configuration.h file:

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

From the main Marlin source you will find:

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

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


As 0scar noted, this looks suspiciously like a JST connector, but the left one is not a JST RCY connector and it is neither one of the common JST PH nor JST XH, JST manufacturer pages show. In fact, it's not a wire-to-wire JST connector. The BQ-store claims it is a 2.5 mm JST connector, but JST has some 10 dozen different types of connectors, some three dozen of them with a 2.5 mm pitch.
"JST Quick" / JST RCY

This one is rated 3A, and looks like the connector on the right, the thermistor one. So if you need to fix that, you know what to get for that.
So what it is?
The connector however looks at first glance suspiciously like this one:

I found this product on several warehouses, listed as 2-PIN CONNECTOR W/HEADER, .10", and even found a specsheet. Those products appear, in design, to be based on the Molex KK 254 from the 2659 series. A genuine Molex 2659-series connector is rated for up to 2.5 Ampere, and looks somewhat similar.
However, the shop did claim it is a JST 2.5 mm pin, and they give a side view:

That is not a Molex KK. It appears more similar to a JST NV, which however has a 5 mm distance between the peg centers (= pitch) and it's rated for 10 A (or 120 W at 12V!). While matching in style it does not match in measurements - as OP confirmed, there's a very close to a 4 mm pitch (+- measurement tollerance) on the connector. So it's not an NV, but something os similar style.

But then it has to be the VH! The VH series has a 3.98 mm pitch, it has that latch and it is rated 10 A, for 120 W at 12 V. In fact, the pins on the Hotend seem to be B2P-VH, matching VHR-2N or VHR-2M "female" adapters.

Safety?
I would not trust a Molex KK 2659-series connector with a heater cartridge on a 12 V Machine! With a 12 V, 30 W Heater cartridge draws exactly 2.5 Ampere, so you'd have a safety margin of 0! That's bad design. A 40 W heater cartridge would draw 3.3 A - that's 132 % of the rating! That'd be a fire waiting to happen!
Only a 24 V machine could be built with a Molek KK 2659 connector and stay within the 2.5 A rating (40 W & 24 V -> 1.67 A, 30 W & 24 W -> 1.25 A) with a safety factor of about 1.5 to 2 to the rating (depending on heater cartridge).
However, this is a JST VH with a rating of 10 A. That means, at 12 V, it's safe for 120 W load, so plenty safe: That's a safety facor of 3, and on a 24 V machine it'd be 6. That's Perfectly safe and sane! After all we look for at least a 5 A rated connector in conjunction with a 12 V/40 W heater.
The more tedious variant to connect safely is to use either an even higher rated connector (requiring replacement) or a continuous wire to the board.


Does voltage or current affect the time to heat a bed more?

It depends on whether you are re-using the bed or not, it is actually the resistance of the bed that determines this in conjunction with the voltage (the current you get for free).

Let's say that the heatbed resistance is 1.2 Ω (depending on the heated bed make and model the resistance is typically in between 0.9 - 1.5 Ω), this means that the power can be calculated using:
$$P = U \times I$$
$$U = I \times R$$
combining gives:
$$ P = I^2\times R = \frac{U^2}{R} $$

For 12 V (assumed default printer voltage) this means that the heatbed power equals about 120 Watt (at a current of 10 A). Running that same bed at 24 V means that the power is 480 Watt (at a current of 20 A). So yes, that will heat up fast, at the expense of an increased current, which is pretty high, and should not be attempted without extra resistance in the loop.

If you're using the laptop charger, the current draw equals about 16 A, which the adapter cannot deliver.

This means that you need to acquire a new heatbed that is able to handle a higher voltage out of the box (more resistance), or you need to put additional resistors in the loop, but beware of the currents. Note that heated beds for 12 V/24 V exist, the wiring is different depending on the voltage. Note that such beds heat up faster, it all depends on the resistance and the voltage, but running the 24 V circuit on 19.5 V (160 Watt bed) is definitely an improvement over the 120 Watt bed at 12 V but still requires about 8 A (only applicable to heatbed that can run 12 V/24 V through extra resistance connections).

Be careful with this and be sure what you are doing!


Pololu - connect motor supply ground and logic supply ground

That depends on how much noise you have on your motor power supply ground.  You definitely want the 100 µF capacitor to have a good high frequency response.  Motors turning on and off can be noisy, and that noise can cause false clock signals in your logic circuitry if you tie the grounds together.


Slicer settings for easy support material removal

Cura has some settings for the support structure which may help.  Somewhere in the full Preferences menu is a setting for "gap at top" or equivalent wording.  If you increase that gap slightly, the support material will be less strongly bonded to the part.   Be careful, since a huge gap could lead to bridging problems.


Creatorbot-3D Kickstarter assembly instructions

In the comments for the Kickstarter, there is a Google Drive link that is still active here.


Which software do I need to start print something?

First; find a model!
To print something you require a model (usually this is in STL format, look into websites called Thingiverse and MyMiniFactory for examples). Once you have a model file, you need to make it readable for the printer firmware.
If you can't find suitable model, then you need to design a model yourself (or ask someone to do it for you) or adjust an existing model to suit your needs. "Good (preferably free) Beginner Software for Part Creation?" is a good place to start.
Second; use slicer software
For a printer to be able to print the model, the model needs to be sliced into layers. These layers need to be printed at specific speeds, temperatures, etc. Search online and look at the filament packaging (usually the ideal temperatures are on the packaging) to find the ideal temperature for your filament. If you are not using the right temperatures, your print will most likely fail. Programs that are able to slice models are called slicers. The most popular free (and Windows compatible) slicers are Ultimaker Cura and Slic3r (or its Prusa distribution).
The slicer produces a printer readable file called a G-code file (file filled with printer instructions for e.g. movement and heating). This G-code file can be sent to the printer using specific printer software (e.g. OctoPrint, Repetier-Host, etc.) but more common or simple is to put the G-code file on an SD card and print the file using the print menu on the printer LCD.


i'd say your extruder driver and/or motor is overheated - really

according to your description - when you've printed other things it was fine but this is the first with such big "flat" area

usually extruder motor works for some time then stops and starts and so on and again so it has some time when driver cools down but here it runs constantly for relatively long time

this overheats the driver and/or motor then is starts to clicks as there is not enough current delivered to the motor

what can you do?

try to take the cover off
check the driver temperature (use electronic thermometer as it can be even 100C)
try to cool it with some kind of fan while running the same printout

if the diagnosis is fine - you are at home and now you know what to do ;)

the one described as E is the one to check and cool down


A number of options exist, but keep in mind that cost will be a limiting factor.

(Small sidenote: cost depends on persective, financial cost does not equal mental cost. The tradeoff between buy or make depends also on your willingness to persist when things don't work right away.)

Before you start: make sure that your printer has enough space to accomodate bigger motors.

So, what options are there?

Change your current configuration. If you are losing steps, it could very well be that it can be fixed in firmware.

Pro: No budget and nothing to lose.
Con: No shiny closed loop system. (Is that bad though?) Possibly need to configure and compile your own firmware.

MacGyver / DIY solution based on low lever components

Pro: Probably as cheap as you'll get depending on how you choose your components. Might be an interesting learning experience, not to mention the satisfaction afterwards. This could be the smallest build size you'll see in all the options.
Con: You'll need a decent amount of engineering and debugging. Might be tricky to mount the encoders.

Same as 1, but now consider using of the shelf stepper motors with integrated encoders.

Pro: Most robust option on a budget in my opinion due to the single mechanical piece (motor + encoder).
Con: Integrated encoders have a considerable cost and are large compared to their vanila versions.

Go for off the shelf motor+encoder and drivers.

Pro: No need to worry about driver configurations too much. Just plug in the numbers or set the dip switches. Very conveinient solution. Pretty much plug and play.
Con: This will already be challenging on a budget. Making a wrong mix and match might lead to unpredictable results such as drives going in overcurrent. (Which, believe me, is very frustrating for your application!)

If we are allowed to consider servo motors: ClearPath-SD series (Or any alternative for that matter!) I'm just including this for completeness.

Pro: Performance wise a clear winner on pretty much any relevant level.
Con: You'll need a big budget!

Bottomline: You'll probably want to give the first option a go before spending money. Next stop, you might want to take the second option (you already did research on different specific low level components), and if you have time to spare I'd go with that as well. If you are also on a budget timewise, I'd definively suggest to take the third option with existing driver boards.

The other options are more cost heavy and become real options in produciton environments, where downtime is also costsing money.

As to the microcontroller, take whatever you have available. Just know that more computational power will allow you to output steps faster and will allow for smoother movements. Lot's to talk about there as well!


How can I tell if an STL model will need supports?

You could try to:

Slice with slicer (Cura in my case) with support enabled.
Search for text: TYPE:SUPPORT

G0 F1800 X237.873 Y184.24
G0 X233.869 Y183.237
;TYPE:SUPPORT
G1 F1500 E562.81355
G1 F900 X233.579 Y183.939 E562.91577
G1 X233.368 Y184.67 E563.01816
If it exists, then try to call it again:
Use auto-orientation plugin to validate if there is a better (no support) model position.

As an alternative, you could scan the mesh and looks for an angle greater than 45 or 50 degrees.


Marlin firmware question for dual extruder

There is nothing to worry about, this is a feature not a bug.

Extruder refers to the active extruder, the loaded/active tool. Based on the active extruder the Extruder controls either your Extruder E1 (this is known in the firmware as Extruder E0!) or your Extruder E2 (the Extruder E1 from the firmware).


G-code wait for extrude command to finish

Are you sure the move didn't finish? That would be very unusual, not the way 3D printer firmware normally operates. A new G0/G1 move command does not execute until the previous one finishes, whether it's extrude-only, travel-only, or a print move (mix of extrusion and travel).
What's probably happening for you is that the amount of material you're trying to extrude cannot melt and pass through the extruder at the speed you requested. At 1800 mm/min, assuming 1.75 mm diameter filament, you're requesting over 72 mm³ of material (nearly a whole cubic centimeter!) of material to be extruded per second. According to some back-of-the-envelope calculations I just did, It would take more than 300 Watts to continuously raise PLA from room temperature to extrusion temperature at that rate, which is not happening without an extreme hotend and power supply.
So, what you're getting is pressure building up between the extruder gear and the hotend (until it starts slipping), causing the material to continue to ooze for some time after the E-axis move finishes, until all the pressure subsides. If your goal is to prime the nozzle for printing, this is not how to do it. It will just end up oozing material all over the start of your print.
You can somewhat fix this by just reducing the feedrate in your command, but that's still not necessarily going to give you great results. The right way to prime is to extrude at nearly the maximum rate your hotend can handle, then retract and wipe before traveling to where the print will begin.


If you have access to an IR thermometer, it would be interesting to verify what the actual temperature is.  I doubt the hot end actually reaches that temperature, but:

if it actually does, then it could actually be dangerous, as most extruders are designed for temperatures well below 300°C.  The problem would likely be in the firmware in this case.
if it stays cold, then probably is a problem with the temperature probe or its cables/connectors being broken. Most printers use thermistors as temperature probes, and thermistors let less and less current pass through the higher the temperature is, so: no current would be interpreted as the hot end being "extremely hot" and the firmware would not heat the hot end further.
if it is hot but at another temperature than the one displayed, then it could either be a problem with the probe over-reading or a firmware bug (e.g.: the temperature is shown in Fahrenheit, or the firmware mis-process the signal from the probe).

Either way: thermistors and cables are cheap to replace, while problems with the firmware may be fixed only if you have access to the code.

If you just bought the printer in a physical store, I would simply swap it with another unit, rather than fiddling with it, though.


Referring to the table provided in 0scar's answer, the key challenge with high temperature materials is the gap between the glass transition temperature (bed temperature) and the extruder temperature.

Polycarbonate for example is listed as usable up to 121°C, printing on a bed at 80-120°C, but requiring an extruder temperature of 260-310°C. This extruder temperature is potentially going to challenge the mechanical, thermal and measurement properties of a printer.

In this application, you don't strictly require 100°C operation, so Nylon (80-95°C) and ABS (98°C) might be worth trying. Even if one side of the part is at this temperature, immersed in steam, the opposite side is exposed to air and convection cooling. Providing there is sufficient thermal insulation and internal rigidity, the upper shell of the part is likely to support it. However, if the inner face does start to flow it may take some time before a problem is apparent.

So long as the material is not soluble, absorbing moisture may not be a major issue.

When it comes to being food-safe, this is a huge can of worms, and you're really looking to investigate 'how much of a risk' rather than get a go/no-go answer.


Surface finish does not really map to the substrate material, Visually, what you have shown could be glass, ceramic, plastic, epoxy or metal.

The surface finish is a combination of the shaping process, any post processing, and any surface finishing. Most significantly, there are a wide variety of custom paints which are designed to mimic specific surface finishes. This means you could carve an object out of clay, then spray it to give the appearance of being sand-blasted steel (to give a specific example).

The underlying material is mostly irrelevant to the appearance. It will be driven by mechanical/thermal considerations (is this a mock-up, or does it need to have functional wall-thickness), and production volume/cost considerations (is it a one off, or are you making hundreds/millions)?


What filaments allow air to pass but not water vapor?

It is difficult enough to make 3D-printed objects water-tight (unless you paint them). Making them permeable to air but not water vapour is too big an ask, I think.


I think you may have used the wrong substance to clean your bed. Try using Isopropyl Alcohol (IPA). You may have left some residue behind from the soap, which is now interfering with adhesion. When that is done, ensure you've gone through the steps for bed leveling again. It's amazing how much of a difference proper bed leveling makes in adhesion. If it still doesn't work, post some pictures up of your results, which will help tremendously in getting you a better answer.


This is a guess but it may be a problem with the sliced file. Take a look though the layers of the sliced file to see if your software is adding a layer there. sometimes it looks fine in the 3d model but it can add a layer while slicing.


Options for making Ender 3 v2 fans quieter

There are companies making fans with blade design based on owl wings to make the blades quieter. Here's an example https://www.moduflow.co.uk/owlet-fans/ and I've seen other designs.  I don't know which design ended up being the quietest.  First, you would need to find out who makes these fans the right size and flow rate for you, then try to find out which is quietest.
Here is another example: https://www.bequiet.com/en/casefans/718