3D Builder is Saying "One or more objects is invalidly defined" Currently, 3D Builder is telling me "one or more objects are invalidly defined. Click here to repair." What is this and what does it mean? When I click it, it totally messes up my model (I can't tell what it even did due to the orthogonal camera). Model stats:

Made with Sketchup
Used STL Exporter to export it
Last I knew what the repairing did to it was to remove my sinks and reduced them to holes in the floor
I used ASCII encoding for my STL (I tried using Binary, but it didn't help)
I tried subdividing it but it didn't help.

Screenshots:

This is a picture of the model before repairing:

This is a picture of the model after repairing:

(Just in case you wonder. I actually have to use STL for this project)

How thick are those walls? 3D printers cannot print zero-width surfaces (and slicers cannot slice them). 3D Builder has tried to make your model printable, but obviously not in the way that you might have hoped for. You need to go back to Sketchup (or some other CAD package) and give the walls a definite thickness (and one big enough for a 3D printer to handle).


Classifying method of control of 3D printers? Is there a classification of method of control most (FDM) 3D printers fall under?

From a 1986robotics textbookref I was reading they defined three classes of control:

1) Pick and place

2) Point to point

3) Continuous path

However, both point to point and continuous path control are stated as requiring servo motors.

I know that the majority of 3D printers are actuated with stepper motors as opposed to servo. Does the continuous path classification still apply? Or is there another classification?

ref - Todd, D.J.(Ed.):Fundamentals of Robot Technology: An Introduction to Industrial Robots, Teleoperators and Robot Vehicles - Kogan Page 1986

The question is if robots classification terminology the textbook sketches applies to 3D printing?

Servos (closed loop) are used in robots to guarantee position (you don't want to accumulate an error after repetitive movement), most 3D printers use open loop steppers that are instructed on a point to point basis through G-code instructions, implying that the use of servos is not a "requirement" for point to point control.

It is a requirement if you want to be absolutely sure that the position is reached. In 3D printing where the loads are generally low, this requirement is frequently dropped. But, there are printers that use servo control.

Note that many CNC machines (operating at much higher loads than a 3D printer) even don't use servo's but (open loop) steppers, these are generally larger and more powerful (more torque).


Altering the print bed temperature at different layers I am using Cura for slicing, and OctoPrint for the actual printing.

On small pieces with roughly one square cm of surface area prints over about 6 mm have a risk of coming off at 60 °C.

In fact, I have had to use 71 °C so it stick properly.  However, I don't want the print bed that hot all the time.  I would like to try a different number of layers at different bed temperatures till I get it right.

Gradually, over the course of 1-3 mm, for the bed temperature to decrease back to 60 °C to save on electricity.  Possibly even 50 °C as the layers get higher.

Cura only support the initial layer having a different temperature and that isn't enough.

Apparently you can have custom user events with OctoPrint, one of them being ZChange which is great.

{__currentZ}: the current Z position of the head if known, -1 if not available

I need on the ZChange event to check the __currentZ and execute anM140 with a temperature varying with layer height.  Normally I would use a simple if command or etc., but how do I implement this here.

However, its seems you can execute a command or a G-code.

I can't seem to find any examples where I can test the Z height in layers or mm and execute a different temperature for different layers.

An additional problem is the increased temps cause the model to melt so that the opening is smaller nearest to the glass than most of the rest of the model.

I am height of the raft, which helps, but I am hoping for a compromise.

The print bed shouldn't need to be 70 °C for the whole vertical height of the model.

Any suggestions?

The actual problem you are facing is bed adhesion, the proposed solution (in your question) shouldn't be the preferred solution to get your parts to stick to the plate/glass as plastic shrinks as it cools down. Note that a 5 °C temperature drop after the first layer usually isn't a problem, but larger temperature differences or shutting off the heat completely will cause your parts to come off the glass.

Note that PLA requires a temperature of about 60 °C (for adhesion as this is close to the glass temperature where the plastic is soft; however, note that PLA can be printed on cold bed surfaces on suitable bed surfaces). The slate of glass is an insulator, so it is perfectly possible that you need to set the bed at a higher temperature to get 60 °C at the surface of the glass plate. When the lower layer deforms the bed temperature is too high.

As you are using Cura, there is a plugin available called TweakAtZ, nowadays this is a default plugin. How to use this is described in this anser (on question "How does one use a heat tower?"); instead of changing the hotend temperature you will need to modify the bed temperature instead (using M140).

To solve the actual problem, you need to prepare the glass by cleaning it properly, use a level bed with a correct initial nozzle to bed distance for Z=0 (usually thickness of a plain paper sheet A4/Letter) and an adhesive like hairspray, glue stick or a dedicated adhesion spray like 3DLAC or Dimafix. I'm using 3DLAC for several years (for PLA and PETG; Dimafix is supposed to be more sticky at higher temperatures, so for ABS for instance) and never had any problems with adhesion on properly levelled beds. See this answer for another user's experience.

An OctoPrint solution using event as you suggest is not recommended. This is the config.yaml, e.i. the configuration of the print server, not a print instance option file. Furthermore, there are yet no plugins that can handle additional code when the head reaches a certain (layer)height. This is pretty tricky if you use Z position detection when the head also can hop, such code should be inserted by the slicer instead.

Related to your question are the answers on question: "Why keep the bed heated after initial layer(s) with PLA (or PETG)?".


Specifying Z offset in Marlin firmware I need to set a Z offset for the Flying bear P902. I calculated the offset (-2.98). But, every time when I try to input this using the LCD screen of my 3D printer, the value jumps to either -2.99 or -2.97. As -2.97 is just a little bit too far from the bed and -2.99 is just a little bit too close to the bed (and -2.98 is perfect), I really want to input this specific value. I have tried many times on the LCD screen and also in the firmware itself.

But, even after uploading the firmware, it still displays -2.97.

This is the line of code I was changing:

#define Z_PROBE_OFFSET_FROM_EXTRUDER -2.98 // Z offset: -below +above  [the nozzle]

Is there a way I can input -2.98?

Z-offset persitently stored in memory?
Maybe the value of -2.97 for the Z_PROBE_OFFSET_FROM_EXTRUDER  is retained in the EEPROM memory when you upload new firmware.
You could try to send the G-code M502 to the machine to re-load the values from the firmware overwriting currently stored values.
Alternative Z-offset using G-code commands
Note that there is a different (and more common) solution to set the Z-offset using G-code M851, you can do this after you uploaded the firmware to the printer. Sending G-code commands can be done using printer software and a USB connection to the printer through a so-called terminal interface. This can be done in OctoPrint, Repetier-Host, Pronterface (Printrun software suite), and probably many more. Alternatively, you could make seperate G-code (basically text files with extension .g) files with each step in a single file and "print" the files through the SD interface of the printer menu.
The following strategy must be followed to specify the Z offset:

Heat your printer up to your printing temperature and allow a few minutes for it to expand and settle
Reset the existing Z-offset to zero M851 Z0
Home all axes G28
Move the nozzle to the middle of the bed G1 X110 Y110 (if your bed is 220 x 220)
Turn off the software endstops with M211 S0
Move the nozzle down so it is just gripping a piece of standard printer paper
Set the Z-offset to the displayed value. E.g. if the printer displays a Z-Value of -1.23 enter M851 Z-1.23
Store it to the EEPROM M500
Important notice! Enable the endstops again with M211 S1 or the printer head will collide with the bed on the next G28 command


Ender 3 Z-limit now unreliable - possible causes and solutions? I had a couple of recent nozzle/bed crashes, so I now frequently do a manual bed levelling. I do these while the bed is heated to allow for expansion.

Today i found, after levelling, a subsequent print could vary from having too much clearance (paper moves very freely) to less than no clearance (which left deep grooves in the bed as per the photo).

What are the possible causes? Is it just a dodgy Z-limit switch or something else? What solutions are available and at what cost? Obviously an ABL seems essential now, but requires a lot of hardware and setup.

Update

Just happened again so here are some more details.

Printing PLA this time.
 - Preheated bed.
 - Levelled bed all over and got a very good raft.
 - Print failed later so aborted.
 - Restarted the same print.
 - Nozzle gouged out a uniform depth trench around print perimeter.

The uniform depth of the gouge indicates a problem related to Z-axis only as bed remains flat and level, but height is out.

I've just bought an Ender 3 Pro and as a guess I would look at the Z axis stepper motor to see if it is not holding position once it stops... the stepper motor has power on it all the time it is stopped to hold it in position.

I would check the plug that feeds power to see if it is damaged or not making good contact.


Building a 3-D printer Building a 3-D printer is obviously a huge undertaking.

Does anyone know of any reasonably cheap guides to build my own 3-D printer?

Building a 3-D printer is actually very easy, assuming that you are electronically and mechanically competent, and there are a whole bunch of websites devoted to doing just that. The principal of which would be the RepRapWiki.

There are a number of different designs, mostly from a few basic designs:

Cartesian
Delta
Polar
Scara

Take a look at 3D Printers Explained: Delta, Cartesian, Polar, Scara, for further details.

I, personally, would suggest looking at the following 3D printer designs (although there are many more out there):

Prusa i3 (arguably the most common/popular), or its derivative the P3Steel
Wilson II
Kossel

On the web, i.e. eBay/Amazon, there are plenty of ready assembled versions, DIY kits, or you can source all of the individual parts yourself. I seriously recommend reading this question What are the pros and cons of collecting parts yourself, versus getting a DIY kit and then modifying it?

I would strongly suggest that you do a lot of googling, and read around the subject for a couple of weeks:

Reading other peoples blogs;
Watching construction videos on YouTube to get a better understanding, and;
Going through the issues that other people have experienced whilst building there own printers

Doing this will help you glean a greater understanding of what is required, and what to expect when building yours - as well as getting an understanding of the individual parts required and how they all fit together.

Spending a fair bit of time on this site, SE 3D Printing, and slowly going through the questions and answers is also strongly recommended.

Building your own printer is, ultimately, more rewarding that purchasing a ready built one. This is because, due to its nascent nature of 3D printing, the printer that you purchase will, most likely, go wrong, and you will need to fix it. If you have built it yourself then you should be able to easily understand what is wrong, and then be capable of repairing it yourself. It is somewhat similar to the situation when the automobile first became popular, back in the 20's/30's (?) - the driver was, usually, also a mechanically competent engineer (unless they were filthy rich and were able to afford to pay a dedicated mechanic to accompany them - which was also the case, in those days).


Printer randomly stops, Is the power supply bad? I have a prusa i3 with Mendel firmware and a RAMPS board.  Recently it has been randomly stopping during prints.  The LCD screen will lock up, the print will stop, and the heating elements will turn off.  Pressing the reset button on the RAMPS restarts the system and it works fine.

In addition to stopping during prints, it has also frozen up while just sitting while on.

My first thought is the power supply (12V 30A) is going bad, but is there anything else I should check before I buy a new one and replace it?

Update:

I replaced the power supply with a new one, and the printer did not stop and completed a print.  I am voting to close the question.

It could be several things.

Your ramps board is overheating or has to much load on it. If you're not cooling the ramps board adding a fan may help the issue.

I know Robo3D had this issue and started shipping with a fan to cool the ramps board.

The ramps/arduino board could be faulty, the firmware may have gotten corrupted or the current version has a bug in the code.

If you are not printing from the sdcard on the lcd controller and using software through a usb connection, that computer may be causing the issue as well.


Cura Sequential Printing I'm trying to get a sequential print going (first time trying this) and Cura won't slice due to build volume issues. From the graphic shown, it looks like this should be sufficiently spaced out but I'm not sure what the problem is. Any tips? I've moved the objects around all over the build volume and it never changes back to "allowable".

If the height of the object is larger than the free space between the gantry and the top of the first printed object, you will not be able to slice the object. The maximum printing height will reduce to the maximum available distance between the gantry rods and nozzle.
Note that the correct Gantry Height needs to be set in the printer properties. For instance, the UM3 I use has 60 mm free space between the gantry and the nozzle:

If you have a smaller height specified, or a taller print object os depicted in the image below, you will not be able to slice the prints (note that a 100 x100 x100 mm is scaled to 20 x20 x70 mm prints, which exceed the 60 mm):

When properly scaled below the 60 mm, i.e. to 20 x20 x50 mm print objects, you'll see that you are able to slice the objects:

Slice preview:


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

Any Ideas?

The clicking sound typically means the drive gears are slipping on the filament because there is a jam in the head/nozzle.
First thing to do is clear the nozzle. You can use a small drill bit to clear the chamber, but if the extrusion hole (at the tip) is clogged, you'll need to get a set of fine wires designed for extruder clearing.  Then heat the head above melting point and slip the wire in (if possible).

In general, I find it easier and faster to replace clogged nozzles.  They're cheap, and more often than not clearing the exit hole enlarges the diameter (bad thing).


Noise cancelling Chiron Y-axis I want to be able to run my Chiron during night-time, but my neighbours tries to sleep at that time of day. I have put a lot of effort into making the printer silent. The controller-fan and power-supply-fan now run slower and only when needed, I have put the printer on those damper feet found on Thingiverse, I have added rods to stabilize the gantry and I have switched to TMC2209 for X, Y and Z. I have made sure the TMCs are tuned for 24V and are using 'stealth chop' below 225 rpm (120 mm/s). The result is impressive compared to how noisy the printer was when I bought it.
One problem was not solved, when Y-axis moves at between 35 and 45 mm/s, the printer starts to loudly vibrate at 220 to 280 Hz. To mitigate that, I first tried to slow down printing, but then print quality was hurt by oozing. Now I have reverted back to my desired print speed, but limited Y-axis feed-rate in Marlin to 32 mm/s using M203 Y 32. It is quiet enough, but many movements are slowed down, affecting quality.
What can I do to stop or mute these vibrations?
ADDED 2021-03-30
I have no proper accelerometer, so I used a MPU6050 accelerometer and some code in an ESP8266. It samples roughly 400 times per second and gives a vibration-value that can be used to estimate the level of vibrations. It is not frequency-compensated, but gives a hint of what is happening. And it can be used to compare settings.
I also made a program based on an example in TMCStepper so I could run the stepper and see/change all settings. This program also relays the measurements from my accelerometer so I can make graphs.
To do this I removed the stepper from the chassis, as I need to be somewhat quiet when doing these tests. It looks like this:

This graph sums up my findings pretty well:

X-axis shows motor-speed in full steps per second, fsps. fsps corresponds to the frequency of the noises I want to conceal. 200 fsps = 1 revolution per second = 60 rpm. On Chiron Y-axis 60 rpm = 32 mm/s = F1920.
Y-axis is shown with the scale log10(accelerometer values).
Here are the TMC-settings I used during the tests, which are same/or close to what Marlin use for 24V Chiron:
(TPWMTHRS was set to 0 when I tested StealthChop)

What I read from this chart (and my many measurements):
TMC2209 is much quieter below 120 fsps.
StealthChop is fantastic at low speeds.
StealthChop shall ONLY be used at really low speeds in a 3D printer. If at all, since switching mode also is noisy.
SpreadCycle use 256 usteps/fstep. A4988 use 16 usteps/fstep. I think that is the reason for TMC to be more quiet at low speeds.
What I do not understand:
Why is TMC2209 seems to be more loud at higher speeds. It might make different vibrations that my makeshift accelerometer rates worse, of course. But can I have a defective TMC2209? Or are the BigTreeTech boards bad? Or have I got fake TMC2209 with worse performance?

Have you tried a concrete tile for garden with foam below it?
Check https://www.cnckitchen.com/blog/reduce-your-3d-printing-noise-with-a-concrete-paver
The same is on

Frequencies at 200+ Hz should not get to the neighbours, the walls and floor will absorb them. Lower frequencies are transmitted much more (see the video).
Try that, it's super cheap, and if not enough let us know for further help.


Which connector should I use between the power supply and the Einsy board? I am looking for a way to easily separate the wires between the power supply and the Einsy board of my Prusa Mk 3S+ with a connector. The power supply delivers 10 A at 24 V.
I thought about a YL wire-to-wire electrical connector as it can handle up to 7 A at 300 V. This should be enough since the two cables share the total load.

The 6 cables (4 power cables & 2 PSU power panic cables) have different diameters. Is it better to use one connector (6 pin) or two connectors (4 pin, 2 pin)?

The YL connectors are rated for wires as small as AWG 26 (and as big as AWG 16). If the power panic wires are smaller than this (or the power supply wires larger) you will need to use a different connector for them. Otherwise, I do not see a problem with mixing different wire gauges in the same connector.


Dimension SST Printer Broken parts My company has an old Dimension SST printer that is out of commission due to a few broken pieces.
I have contacted the Stratsys folk and they won't do anything until we purchase a multi-thousand dollar service policy.
I also have a Makerbot that I can use to create spare parts however, can't find pictures of the original configuration.
The broken pieces are the Toggle Bar and Z Foam Sensor and whatever parts used to hold them in place on the head. Toggle Bar circled in red  View of my printer where the toggle bar used to be

Two Questions:
Does anyone know of a location to purchase spare parts?
Does anyone have detailed pictures (360 view) of the print head they are willing to share so I can recreate the parts/attachments.

Thank you so much for any help!

Seeing as how no one has been able to find a solution yet and I'm not familiar with your machine, I would recommend reverse engineering the part to the best of your abilities. If you don't have the right tools, try finding a local machine shop and ask if you can use their measuring equipment. Sometimes you might get lucky and they will have something more intuitive than callipers, such as a CNC CMM or CMM Arm. As far as acquiring the part, try asking the machine shop if they can produce it, or get it 3D printed via 3D Hubs, MakeXYZ, or some other peer printing service.

I'm sorry I don't have a more direct solution, but hopefully it at least a general sense of what options you may have.


How to set a new homing position using software and/or slicer without changing hardware end-stop? Before the question, here is my setup;

Prusa i3 (with mainboard Mks Gen v1.2)
Repetier as slicer
Marlin source code

My main task is to convert my 3D printer into a chocolate printer.
I have replaced the filament extruder with a chocolate extruder. And it is there that my issue began. Because, the new extruder is stopping slightly off the y-axis when homing. It is going out of the standard 20x20 cm bed. The other X and Z axes are OK.

So, I have played with the #defines explained below, but I couldn't even make any single mm difference by homing. They are all ignored when the printer is homing. It goes and rests on the hardware end-stops and stops there eventually.

All I want 10 mm offset for Y axis.

Started with this;

// Travel limits after homing
#define X_MAX_POS 200
#define X_MIN_POS 0
#define Y_MAX_POS 190  <<<< (tested with 190 and 210)
#define Y_MIN_POS 0
#define Z_MAX_POS 200
#define Z_MIN_POS 0

and this;

// The position of the homing switches
#define MANUAL_HOME_POSITIONS  // If defined, MANUAL_*_HOME_POS below will be used

//Manual homing switch locations:
// For deltabots this means top and center of the cartesian print volume.
#define MANUAL_X_HOME_POS 0
#define MANUAL_Y_HOME_POS 10 <<< (tested with 10 or -10)
#define MANUAL_Z_HOME_POS 0

I have also played with the slicer tool (Repetier) settings where homing related values are mentioned but no joy there as well.

Any input highly appreciated.

The Y-Max setting does not help, because it is the software end stop for the  other end of the axis.

The Y Home position also doesn't help as it only changes the coordinate that the printer assumes for when it hits the home position. That is used for printers (like deltas) that home to the max end switches.

What could help is a little bit of G-Code right after the Homing. The Homing is a G28. Just add a G1Y10 after that. That will move your Y Axis 10 mm right after homing. So it will then be in the position that you want. If you then add a G92 then this position will become the home position for the print. So adding these two lines should fix it. Cura lets you edit these start G-Codes so that it then will automatically add the modified codes to all your prints.

You can also try a G10 (with a firmware that supports it.

For Details on G-Codes see:  http://reprap.org/wiki/Gcode


How to fix transparent outer face? I have a 3D model that is essentially a mostly outer cylinder but with some geometries in the inner wall. However, it seems that MakerBot print software is having trouble interpreting places when the outer wall is just a thin face (with no thickness) and makes the model seem transparent there when looking from the inside, even though it looks solid from the outside. I think for this reason, the model is completely filling in the cylinder in those places, which is what I am trying to fix.

Any suggestions would be appreciated.

You've not offered the source of the model, nor the software from which it was created, but I suspect that you'll find the "invisible" faces have reversed normals. This is a characteristic of modeling software that believes the outside is the inside and vice versa. If you are comfortable with using another program, you can check/confirm those problematic sections.

I'm fond of Meshmixer, a multi-platform 3D modeling and editing program. It will display reversed normals with a bit of zebra striping. One can use the Select tool, highlight those faces and use the Select Edit, reverse normals menu entry to repair the problem.

Some slicers will automatically repair this type of problem. For a different approach, download and import your model into Slic3r, which will indicate that it has corrected xx errors.


Air printing/jamming midway through raft creation For a school project, my teacher gave me a brand new Longer 3D printer to create parts with. After one good job, the printer cannot get past the raft creation without air printing. The thickness of the printed filament tapers down until no filament is coming out. I do not believe there is a jam in the hot end because if I remove the filament and cut off about 4 inches, the printer extrudes as normal.
I am using 1.75 mm PLA on a Longer 3D PK4
When the problem occurs, the extruder continues as normal but prints out very little filament. The extruder drive gear also ticks backward as if it cannot supply enough force to move the filament forward.
I have tried decreasing the speed, increasing the temperature, turning off retractions, but none of those options seemed to have any effect on the problem.
If videos or pictures could be helpful let me know what to include.
Edit:
My working idea of what's wrong is that heat creep is causing the filament inside of the heat sink to soften causing the filament to thicken and Jam. I could be wrong.

Figure one highlighting how the filament thins over the course of the raft creation until no more filament is extruded.

Figure two showing how random parts of the filament is thicker than others. The thickness is noticeable and once I cut this section off, filament flows freely through the Bowden tube without friction. With this section, the filament is difficult to remove and requires more force.
I have tried:
increasing the interface thickness to .4 from .27 and from .4 to 1
increasing the print speed from 50 mm/s to 90 mm/s
allowing the printer to cool off.
decreasing the temperature to 190
During the print, I have noticed that the heat sink is hot to the touch during the raft creation but cools off once the fan starts spinning.
The fan does not spin at all during the creation of the raft. But spins at full speed once the actual print has begun. Longer does not have a setting inside their software to change this.
I have gotten a few really small prints to work with print surfaces smaller than 2 cm wide
The prints themselves turn out great if they get past the raft stage. (only for small prints) This additionally leads me to believe that heat creep is the problem and that the fan not being on is the cause.
Let me know if you have any ideas.

Your symptom sounds like heat creep might be stopping the extrusion.  See if this discussion helps you troubleshoot: Understanding all the ways to avoid heat creep
Note: decreasing speed and increasing temperature makes heat creep worse.
Your picture of filament shows what people with Bowden extruders describe as typical of heat creep.  The Bowden tube isolates the filament drive motor from the temperature of the extruder.  On well put together Bowden tube extruder, there is no place for softened filament to bunch up. So, heat creep occurs when the melted filament goes up the region of the heat break in the heat sink.  Thus, to determine heat creep one needs to ask, "Is the expanded part of the filament extending into the heatsink.


Move print bed to front at the end of a print rather than the back I have a Monoprice Maker Select Plus, currently using Ultimaker Cura 3.6.0 with the default settings for a Wanhao Duplicator i3 Plus. Right now when a print finishes, the bed retreats towards the back of the machine. I'd rather present the bed forward for easier part removal.

Here is my ending G-Code:

M104 S0      ;extruder heater off
G91          ;relative positioning
G1 E-1 F300  ;retract the filament a bit before lifting the nozzle, to release some of the pressure
G1 Z+0.5 E-5 X-20 Y-20 F{travel_speed} ;move Z up a bit and retract filament even more
G28 X0 Y0    ;move X/Y to min endstops, so the head is out of the way
M84          ;steppers off
G90          ;absolute positioning

It looks like I need to change that G28 line third from the bottom, but I'm not sure what to change it to. I've not yet done any g-code manipulation of my own. I don't know what units it's using, and it looks like it still has relative positioning, so even then I don't know it's a good idea to just set it for the max size of the bed.

So how can I change this code to move the bed as I want?

Note that this reference states that:

  Because the behavior of G28 is unspecified, it is recommended not to automatically include G28 in your ending GCode. On a Cartesian this will result in damaging the printed object. If you need to move the carriage at the completion of a print, use G0 or G1.

So you need to use a G0 or G1 move.

When using Ultimaker Cura (like many other slicers), there is built in functionality known as keywords with a complete list found here.

The keyword machine_depth is the one that is of use to you, embed this in your end G-code in between curly brackets and it will expand to the bed size of your machine (replacing G28 X0 Y0):

G1 X0 Y{machine_depth}

For me this compiles to (e.g. for my coreXY printer):

G1 X0 Y300

To set the speed, just add the following command prior to the one above:

G1 F2500

Adding this line before the actual move ensures that the speed is constant, if F2500 would have been included in the move command (like G1 X0 Y{machine_depth} F2500), this defines the end speed, it would start moving at the last speed value prior to the move.

This results in adding the following lines in your endscript:

G1 F2500
G1 X0 Y{machine_depth}


Danger in 3D printing over a lithium ion battery So I bought a Lulzbot Mini a couple months ago and finally downloaded Ultimaker's version of Cura... Boy... have I been missing out...

One feature Ultimaker Cura implemented that I've been looking for is a "pause at z-height" feature ("post-processing tool"). I'm building prototypes of an electronics device, and creating two pieces that snap together looks a lot worse than printing a single piece. If I could pause my print, insert my electronics, and continue printing, my device would look a lot more professional (even if it took longer to make).

My one concern is the lithium ion battery. Right now I'm printing in TPU. With a heated bed of 40 degrees Celsius, and a heated extruder at 240 degrees Celsius, there seems to be a significant risk that the lithium ion battery reaches a temperature above 60 degrees Celsius (damaging the cell, causing a potential explosion). Granted, I am not sure what "60 degrees Celsius" actually means. It could mean only one part of the packaging needs to reach this temperature, or it could mean the entire LiPo's internal temperature would need to reach this. In either case, the numbers don't look good.

On the other hand, the heated bed surely doesn't need to remain heated beyond the first few layers? Additionally, I can create a "roof" for the LiIon battery that I can slip it under, providing some insulative TPU before the rest of the device. I think the print would happen safely like this, but obviously, an explosion would be really really bad. Like it would probably burn my house down, and I would be asleep when it happened.

Does anyone have any experience doing this?
Is there a way to turn off the heated bed mid-print? I guess I can insert a g-code line during the pause? Will this affect the remainder of the print you think?
Am I being paranoid? Can the extruder actually pass heat through a 1–2 mm of insulation and cause an explosion?
Anyone know how heat travels from the initial, liquid print material through the rest of the structure?

Any more advice or things I should consider before pursuing this?

A more specific pause type might be helpful, if anyone knows of any.

I would have to see your design to comment more but why not just change your model with the lid or top that can be either fused on later or attached in some other fashion?

It is possible to turn off the heated bed after a certain layer. It looks like there is a discussion here with the G-code: Can Cura Turn Off a Heated Bed Partway Into a Print?

I would personally avoid exposing the battery to the heat generated by the hotend or the build plate. Printers alone can burn your house down. Why combine it with the awesome power of a lithium ion battery?


FDM: Clear=transparent part I intend and would like to print a transparent hemisphere. I have a Taulman T-Glase clear 1.75 mm filament and I have XTC-3D.

You can read this interesting page, Hacking t-glase to look more like glass!

First question, what kind of printing settings should I use? Should I go for a low infill percentage or a high one? Should I go for line or hexagon? I would say 5% line but perhaps there is a better setting.

Then, how should I use XTC-3D as mentioned on the above link? I'm a little bit confused how it can make the part more transparent.

First I would hedge your expectations.. I am very familiar with t-glase. It is very translucent but it is not clear and no amount of post treatment will make it 100% clear. Their example is the only exception where you have a simple print where it has only a single layer. By applying the clear coating they have normalized the wall and made the surface even. Thus no more light diffusion.

You could likely get the same effect with good sanding but good luck sanding a 1 wall thick print. Also note they do not show any solid parts. If they cannot get a solid part to look good and clear, then really you shouldn't expect to be able to.

Any infill will cause it to be non clear. Any extra shells will also create air pockets, lines, etc and make it non clear. If you really want clear, FDM is not the way to go. The only way I could imagine to print an item clear with FDM is to create a cast, then cast it with resin or glass..

If you consider how the plastic is applied, you can see there is no real way make it 100% air pocket free.. See below,

Image taken from here.

The best I can recommend for settings. Make your temp spot on. If you boil the material you will have less translucency. Play with over extruding (too much material) in a Limited amount. Might reduce gaps. I would also try to print in BIG THICK lines. Less lines, less diffusions.


Hooking up an optocoupler in a 24V Machine, is a 2 kOhm resistor sufficient? I am going to buy an inductive probe for my Creality Ender 3 to enable ABL (Automatic Bed Leveling). And now, I have one last question left on my mind:

I am going to buy a Vishay Optokoppler Phototransistor SFH610A-1 DIP-4 Transistor DC.

Is it sufficient to put a 2 - 2.2 kΩ resistor between the input of the octocouplers LED side and the 24 V Output of the probe, to lower the current and voltage enough to work with the octocoupler? Or do I need something else?

On the transistor side, I will simply attach the 2 wire Z-endstop cable, +5 V on Collector and GND on Emitter.

TL;DR
Yes, a 2 kΩ resistor is sufficient to limit the current to about 12 mA through the optocoupler. With a maximum current specification of 60 mA you require at least 400 Ω; any resistor in between the values should be suitable for this optocoupler component when used at 24 V. More information is found below.

Having a glass bed and using an inductive probe may not work optimally. In such cases a 3D touch sensor is a very good alternative. For inductive sensors, remember that these sensors optimally detect steel, aluminium is harder to detect (about 60 % less than iron; a glass sheet in between the bed and the sensor requires you to acquire a sensor with a large detection range, e.g. 8 mm or more. To optimize the detection distance such sensors need to be powered to the maximum voltage they can handle (usually 36 V) or the highest voltage you have available (e.g. power supply 12 or 24 V). To protect the board, that is only allowed to receive up to 5 V, an optocoupler is an excellent way to guarantee the separation of voltage levels.
Considering your questions, it is fair to assume you are not an experienced electronics tinkerer, purchasing an optocoupler module is the best alternative, you just screw the wires into the respective input screw terminals as shown in this answer.
As the optocoupler separates two circuits, you can safely use 24 V on the one side and the 5 V on the other side, you do not need an additional resistor when you use a module board. If you plan to buy separate components to build your own circuit, you need to look at the maximum current that the optocoupler can handle on the input side (that will be 24 V). From the documentation from the optocoupler one reads that it is limited to 60 mA. A maximum current would therefore require a resistor of:
$$ R=\frac{U}{I}=\frac{24}{60\times10^{-3}}=400\ \Omega $$
My 12 V optocoupler module uses a 1 kΩ resistor implying a 12 mA current. In your case allowing 12 mA of current yields a 2 kΩ resistor.


Printer homes to Z stop-switch, but presses on heat bed during printing I have a Prusa i3 that homes properly when you use the menu. After adjusting the bed and homing several times, it keeps the head at a reliable distance. However, when I try to print from an SD card, the printer buries the hot end in the heat bed.
What needs to be adjusted to fix this issue?
G-code from one of the 2 files
M190 S50.000000
M109 S200.000000
;Sliced at: Mon 13-06-2016 15:39:25
;Basic settings: Layer height: 0.2 Walls: 1.2 Fill: 20
;Print time: 3 hours 47 minutes
;Filament used: 11.435m 34.0g
;Filament cost: None
;M190 S50 ;Uncomment to add your own bed temperature line
;M109 S200 ;Uncomment to add your own temperature line
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
G1 Z15.0 F3000 ;move the platform down 15mm
G92 E0                  ;zero the extruded length
G1 F200 E3              ;extrude 3mm of feed stock
G92 E0                  ;zero the extruded length again
G1 F3000
;Put printing message on LCD screen
M117 Printing...

;Layer count: 446
;LAYER:0
M107
;LAYER:1
M106 S127
G1 F2400 E-4.50000
G0 F3000 X81.474 Y58.603 Z0.300
;TYPE:WALL-INNER
G1 F2400 E0.00000
G1 F2220 X83.063 Y56.456 E0.06663
G1 X84.277 Y55.080 E0.11240
G1 X84.836 Y54.444 E0.13353
G1 X85.799 Y53.476 E0.16759
G1 X86.755 Y52.587 E0.20015
G1 X87.179 Y52.244 E0.21376
G1 X88.836 Y50.911 E0.26680
G1 X89.285 Y50.610 E0.28029

The correlation between the endstop switch  -- or sensor -- and the surface of the bed is not known a priori .  In your case, there are two possibilities.  I'd say the more likely is that your g-code generator is not setting the Z-height offset from the bed correctly.   The other is that your bed is tilted, so proper Z-home at one corner does not match the entire bed.

Try this:  first manually move the extruder head to all four corners and adjust the bed screws until the separation is identical at all times.   Then let your gcode start up -- and don't worry if the extruder depresses the bed during homing, as that doesn't matter.  See where the extruder is once the print starts.  Adjust the endstop switch up or down to compensate until the print head when printing is just off the surface and the first layer adheres well.

If all that doesn't work, then you may have the wrong printer profile settings in your slicing softwqre.


How do I set the flow rate on my Ender 3 Pro and have it stay at that percentage? I am trying to increase the flow rate on my Ender 3 from 100 to 108 % but every time I start a new print it reverts back to the old 100 % flow rate. I have clicked through the settings and pressed the "store settings" button but it still reverts back at the start of every print. I don't want to do this in my slicer settings as I run 18 Ender 3's so I want to be able to use the same G-code for each.

Changing the flow rate during a print can not be saved. There simply is no way. It is usually meant to be a fix with filament inconsistencies or to look for the right extrusion factor for a new filament batch.
Slicer
The only way to consistently increase the flow rate would be  to alter the flow rate in your slicer to what you have found to work best for each machine, probably using separate profiles. This will up the rate for every subsequently sliced print. Note though that this 108 % increased extrusion is converted extrusion factors that are simply numerical and 1.08 times the normal in the g-code. These numerical values will be taken as 100 % by the printer - and since it requires extra work to slice the gode for different profiles it is not the optimal solution.
As you elaborated though, this is not a doable thing, so let's look further.
Source hunt & Workaround
Since only one printer is showing underextrusion while the others do not, it is time to check the hard- and firmware:

underextrusion can be caused by a defective extruder assembly or a damaged or blocked nozzle.
if a machine has consistent underextrusion, its steps/mm in the firmware might be off. This could be altered and stored in the EEPROM. Since this could be a machine unique setting, here would be your point of attack to increase the extrusion of just one machine while using the identical G-code to all other machines.

Note that the standard firmware of the Ender-3 in 2019 did not contain Thermal Runaway Protection (What is Thermal Runaway Protection?) and should be upgraded because of this anyway. You have to flash a bootloader too, so in the process of doing the upgradeability and safety-upgrade to all the machines, you could store the altered steps/mm to each machine individually so they get consistent output.


gcode to move the printhead up for maintenance I've got a Monoprice Mini Select (15365) and it takes FOREVER for me to manually spin the dial to get the printhead to raise all the way up so that I can perform maintenance (clear blockages in the nozzle or apply new tape to the bed, etc).

So, I was thinking about writing a snippet of gcode that I could just run which would contain the commands necessary to do that for me. I'm a n00b to 3D printing, but I'm an old programmer so I figured it would be too hard. However, before running this code on my printer, I wanted to get some experts to double check me to make sure I'm not going to hurt anything. :)

Here is what I have, please let me know if I've done anything wrong or if you have any suggestions.

; Move print head to center and top to prepare for cleaning/maintenance

M107    ; fan off
G28 ; home all axes
G21 ; set units to millimeters
G90 ; use absolute coordinates

; full dimensions of the print area are 120mm x 120mm x 120mm
G0 X60 Y60 Z119 ; move to center X,Y and just below the max height

M84     ; disable motors

I grabbed a few lines from gcode generated by Slic3r and used the gcode wiki entry to understand each of the commands and fill in the extra ones I needed.

Yes, on machines which will execute "standard" gcode, this will do what you request. Some good resources are http://reprap.org/wiki/G-code and https://en.wikipedia.org/wiki/G-code


SLA prints not sticking to build plate I have been working with our SLA printer (Facture Draken) for a couple weeks now printing in makerjuice waxcast.  .  I have had some successful prints, but the majority (80%) end up as  pancakes stuck to the bottom of the resin tray. Some others break in half mid print.

I have experimented with laying my models (round circular diks) flat on the build plate, but most of the times I place them on supports which stem from a square baseplate.

It seems clear to me that there is allot of force being put on the models while curing on the bottom of the resin tray.  I have noticed that printing objects with a larger projection area are more likely to stick in the vat.  I assume this is because of the increased contact with the tray.  Usually it seems ~10 layers are built before my baseplate breaks away.

Things I have tried

Pulling out the build plate, cleaning it with Acetone.  Sanding it with 80 grit sandpaper.
Emptying the resin tray and replacing with new resin.
Upping base-layer cure-time from from 30seconds up to 3 minutes, and variations between.
Upping base-layer count from 2 to 4.
Rotating model base 45% to start the tray peel process from a corner rather than from a long edge to reduce initial tear force.

Anyone with experience got more suggestions on how to continue troubleshooting?

Prints could end up on tray for couple of reasons.

Vacuum force on early layers - Usually you should lose pieces on the center of platform

Put holes or channels on platform
Very slow speed on early layers
Use smaller platform
Use tilt mechanism
Use larger support structures
Use stickier platform - Anodized aluminum is specially good

Non-aligned platform - Pieces on side of platform end up on tray

Align platform / tray

Low cure times - you could lose pieces around platform for DLP and whole platform for LCD ones
Resin related issues

Resin designed for thinner layers - Decrease layer thickness
Pigment settled down - Shake resin before use


Why are the STL files for the Ultrascope telescope at 45 degree angle? I began printing the parts for the Ultrascope DIY telescope designed by the Open Space Agency.  See http://www.openspaceagency.com/ultrascope.

All of the STL files for the 3D printable parts are canted 45 degrees.  Brackets, tubes, everything I have seen so far.  Is there a reason for this?  I printed one part last night and simply rotated the part so it would lay flat because I didn't want to deal with supports.  I am relatively new to 3D printing -- Am I missing something I should know?  Is this a thing?

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.


Creality Ender 3 - printing in front of the build plate I am trying to print my first test but my Creality Ender 3 starts printing near the front edge and within 10 seconds is printing in front of the tray (off onto my table).  I really think it should be starting the print in the middle and then never going so close to the edge and even over it

What can I do?

When a print is not printing on the build platform, you either:

Have the incorrect settings in the slicer (e.g. Ultimaker Cura, a common mistake is that the "origin at center" option is active), or
Have the center of the bed incorrectly stored in your firmware. (See: How to center my prints on the build platform? (Re-calibrate homing offset) or Recalibrating Home-position).

Note that the most simple change (after you verified the slicer settings and confirmed that it still does not print in the center) is adjusting the settings in the slicer (bed settings, of start G-code script), this way you do not need to compile and upload new firmware (e.g. if you are uncomfortable or inexperienced in doing so), but, fixing it in the firmware is the best solution. Why? If you change the offset in the slicer you force the bed dimensions to a new position that you know where it is, while if changed in the firmware, the printer "knows" the actual size and the limits.

To fully answer your question, we need a little more information what slicer you use and what the current settings are. From your question it sounds as if the offset is more than a few millimeters. Usually this hints to an incorrect slicer setting (frequently Ultimaker Cura).


Car Body shop Printers What type of printer would one recommend to print and cast car body parts fast on a large scale? Also if I were to print parts for restoration would I need licences from the manufactures?

The Materialise Mammoth printers seem to be the predominant choice for manufacturing car body parts. However, any sufficiently large printer (e.g. bigrep) could work. That said, car body parts are quite a challenge to 3D print given how excruciatingly long such large parts take (exacerbating the probability of failure). You will have to very carefully consider whether 3D printing is right for your application (it probably is not).

The licensing part is extremely complicated. You'll have to deal with patents (perhaps the body part incorporates some clever patented feature), trademarks (you generally can't reproduce manufacturer's logo's) and copyrights (if the part is very "artistic" it might be protected by copyright, but this is unlikely). A simple, functional part such as a body panel would generally not be protected by any of these but these three things are the main reason why you might need a license.

In addition, you have to be careful as to which materials you use, as these will (most probably) not be as strong/durable as those that are produced by car-parts-manufacturers. Furthermore, if you print the parts yourself, install it in a customer's vehicle, and the vehicle malfunctions, as a result, you may find yourself being sued.


PID autotune fails under all conditions so far. Any ideas I haven't tried? I got some Prusa i3 clones with Melzi boards with Marlin, or nearly so. One of them performed very well (considering that the board would reboot whenever power was applied to the build plate. But I digress) until finally the hot end failed, possibly due to me running it for two days with little respite. The replacement, a typical MK8 clone, installed almost painlessly but failed to start due to over-temperature conditions (we're talking as much as 45 °C over set temperature).  I tried the known solutions, continually reducing my P value (got down to 7 before I gave up) and attempting autotune. I also tried autotuning to both higher (230 °C) and lower (150 °C) temperatures.

None of these seemed to produce an autotune successfully, and the same error message temp to[sic] high appeared in all cases. Can anyone suggest something besides a new hot end (I have one on order, but what if I have the same problem with another new one)?

Turns out I'm using a 12V hot end and should be using 24V. I looked up the resistance to be sure; so no amount of tuning the PID would fix that.


Why would all of the Ender 5 Pro's axis motors (X, Y and Z) stop being able to move (all at once)? I have a Creality Ender 5 Pro which has been working properly for some time. During my last print, the axis motors just suddenly stopped working while the extruder motor continued to work properly.
In fact, when I connect the extruder motor wire to any of the axis motors, they respond correctly (mimicking the extruder motor) but neither works or moves when connected to its own wire(s). As a result the printer does not print anymore.
Here's what I've tried:

Switching the wires around to check if any motors are damaged (none are).
Restarting the Creality
Checking the output on the power source (which is 24 V and about 14 A)
Checking to make sure all motor wires are connected correctly on the SKR MINI CONTROLLER (all seem fine) and checking that the board is powered.
All external connections also seem fine.

I'm quite confused why the axis motors would not be working all of a sudden. I'll appreciate your help if you've faced this problem before.

The Creality V1.1.5 board was fried. I replaced it with a BIGTREETECH SKR MINI E3 V2.0 32BIT CONTROLLER. After struggling to find a corresponding firmware for the Ender 5 pro, the axis motors worked correctly.


Whats the difference between a basic rapid prototyping machine and a 3D printer? In general 3D printers are compact and smaller than RP machines. That's ok. But, what's the difference? 3D printers can be used as RP machine too.

All rapid prototyping means is automatically producing a physical part from a cad model. 3D printing is a way to achieve rapid prototyping. There are 2 main methods of rapid prototyping: additive, and subtractive.

A 3D printer is additive- you add materials to an object layer by layer.

Usually, when people talk about a subtractive machine, they are talking about a CNC mill (or lathe), which tend to be extremely large (most are over one ton). You start with all the material there, and you subtract the material that you don't want. This might be what you are thinking of.


Face where there should be no face When importing this .stl file in Creality Slicer another face appears in the middle when viewed in layered view. This face is not visible in my 3d modeling software Blender. I tried cleaning up the model a bit and to triangulate the faces myself, neither helped and the problem is still there. Also I didn't find anything online.

At the intersection of the top and bottom planes of the cross-piece and the cylinder, there are non-manifold edges. Meshmixer is able to identify this problem but cannot repair it. My slicer, Simplify3D also identifies the faults and prints a solid cylinder between the planes. Prusa Slicer 2 also creates a solid at that location.

As you've indicated that you are the creator, consider to use the 3D printing features within Blender to assist you with repairing the problem locations.

  File ‣ User Preferences (or Ctrl-Alt-U)
  to open the User Preferences menu.

  In the Add-ons tab, start typing 3d print into the search bar. Once
  the “Mesh: 3D Print Toolbox” shows up, click the checkbox on the far
  right to enable this add-on.

  Close the User Preferences window.

  In the Tool Shelf, there should be a new 3D Printing tab.


How does one use a heat tower? I've been asking around on how to choose the right temperature for a given filament. I noticed that with two different brands of pla I have to print at different temperatures, and the manufacturer specifies a broad range of print temperatures.

I keep hearing about heat towers, and have found various examples on thingiverse.

My question is how do I actually print one? And then, how do I judge the results?

When you slice an STL of a heat tower, you need to tell the slicer that you need a different temperature at a certain level and maintain that new temperature until another change is requested.

The way I usually do it is by using a post processing script in Ulltimaker Cura, but you can do it yourself quite easily by changing the G-code file manually.

To get it to work in Ultimaker Cura is to:

open a heat tower STL model onto the virtual build plate,
choose the correct print settings, e.g. fan speed, print speed, layer thickness, etc.,
now navigate from the main top menu bar Extensions -> Post Processing -> Modify G-Code,
select Add a script and choose ChangeAtZ,
you now are presented with an option (called Trigger) that you can change options at either a certain Height or at a certain Layer No. number, you decide what you want to use based on the model and layersize used, but height can be chosen safely when you know the height changes in the heat tower model
set a certain height at which you want to change the print properties by specifying a height in option Change Height,
now put a checkmark in Change Extruder 1 Temp (be sure that the box Behavior is set to Keep value so that it maintains this value until you specify otherwise, else it is only valid for a single layer),
a new input box will be presented to you where you can enter the value of the extruder,
repeat this adding of "changes at certain height" e.i. instances of ChangeAtZ until you have specified all the temperatures for all the levels
now slice the model (if not done automatically) and save the G-code file for printing.

If you look into the generated G-code file (the snippet below is taken from a G-code file for an Ultimaker 3) you will see that the post processing script will add extra lines in your G-code file. E.g. the following snippet shows you 2 changes of temperature, one at 5 mm (extruder 1 @ 250 °C), the other at 10 mm (extruder 1 @ 245 °C):

...
;LAYER:48
G0 X93.4 Y132.161 Z5
;ChangeAtZ V5.1.1: executed at 5.00 mm
M117 Printing... ch@  5.0
M104 S250.000000 T0
...
...
;LAYER:98
G0 X93.4 Y132.35 Z10
;ChangeAtZ V5.1.1: executed at 10.00 mm
M117 Printing... ch@ 10.0
M104 S245.000000 T0
...

The bottom line is that the extruder needs to be instructed to be heated or cooled to a new temperature. This is also something you could have inserted yourself manually by adding the codes M104 SXXX.000000 T0 at specific levels where XXX is the extruder temperature you need for that level.

Basically this describes how to print the heat tower calibration prints, not the selection of the settings (e.g. extruder temperature) to use for your prints. When you created the print file you are ready to print the tower and observe the quality of printing. You can look at the print and visually inspect the temperature giving you the best aesthetic performance, the best overhang performance, the best "filling" performance, highest speed, etc. It is you that decides what is best for your application. Alternatively you could print some coupon tests and see which are structurally the best. Please note that additional towers for different settings like layer height, print part cooling and print speed to may be necessary to optimize the print process.

Sidemark, I prefer the use of parametric models (e.g. in OpenSCAD) over the STL models found on the internet, this way I can embed the exact printer setting in the tower for reference. See e.g. this answer.


MK8 extruder showing 500+ °C on temperature sensor? I just finish building a Graber i3 printer from mixed parts (a MDF clone of Prusa i3 MK2). For the hotend, I've bought the Greetech MK8 extruder. However, the temperature sensor is driving me up the wall.

I've already checked the wires and connections, but the darn thing keeps showing a steady 500 degrees Celsius. In Marlin, it shows it right up (I'm using the 1st option for a 100k thermistor), in Repetier Firmware (using the same one), it shows 0.00°C, until I tell the printer to heat up, when it shoots to 500°C just like before with Marlin. The documentation for this extruder only lists it as a "100K NTC Thermistor", so I tried to select one of the NTC options on the list for both Marlin and Repetier and the temp sensor reads steady 3.600°C!!!

Measuring it with the multimeter, it shows around 60k, it's 31°C outside.

Is it broken or am I selecting the wrong thermistor type?

Documentation for MK8

A brand new thermistor shows about 95-105k ohm (depends on the multimeter quality), so it looks like that one is out of the range.
To be sure that it is a thermistor, you could connect a 100k potentiometer, play with it and see readings on the lcd. If the readings are OK, then mainboard is good so replace the thermistor.

A 100k thermistor curve


Printrbot Simple + OctoPrint on PC not working I am running the newest version of OctoPrint server on my Windows 10 PC, and accessing it with Mozilla Firefox on the same PC.

I also installed Cura 15.04 and selected the Printrbot Simple profile, and pointed to the Cura install path in the OctoPrint client so that it can use it for slicing.

I plugged in my printer and it was recognized by OctoPrint. The nozzle temperature is correctly shown, and I can turn the fans on/off in the control tab.

However, I cannot do anything else in the control tab, including moving the axes. I have not imported any sort of printer profile into OctoPrint, since I cannot figure out how to or where to find my printer's information.

There has not been any kind of calibration process I can find either.
Can anybody help me find a print profile/calibrate my printer, and just get it working so I can move the axes/print something out?

Before any axis can move the printer must be homed correctly (G28 command, or an equivalent home button, there are 2: an X/Y and a Z button). A correct printer profile must also be defined; this profile contains some bed geometry and speed data, these are some basic values that are easy to add through the wrench button and "printer profiles" menu item.

Note that Cura 15.04 is very old, more recent version with far more options and better stability can be downloaded, but won't work integrated in OctoPrint, instead you download the most recent version of Ultimaker Cura directly from Ultimaker.com slice your product and store the G-code file to later import this into OctoPrint.

Please take care in choosing an optimal power plan in Windows 10, if your computer goes to sleep during a print (or updates or crashes) your print is lost; using a Raspberry Pi is far more safe.


Nozzle jumps off the bed when using Marlin Mesh Bed Leveling I am using Marlin firmware with a RAMPS board on an Anet A8 printer.

The bed size for the printer is 220 x 220 mm and that is stated in the configuration.h file. When using mesh bed leveling, the nozzle jumps to the first corner on the bed perfectly after setting the x-min to 5.0 but the next two points are off the end of the bed. Here are my settings:

// Travel limits after homing (units are in mm)

 #define X_MIN_POS 5.0
 #define Y_MIN_POS 0.0
 #define Z_MIN_POS 0
 #define X_MAX_POS 220
 #define Y_MAX_POS 220
 #define Z_MAX_POS 240

What could be my issue?

None of the answers address your question to solve it! The only sensible contribution comes from a comment of @TomvanderZanden.

For the sensor to stay within the limits of the bed (considering the offset of the sensor and the size of the hotend carriage) you need to define where the sensor (plus carriage) may go to (to keep the sensor also on the bed, you also need to define the sensor limits). The suggested constants are important in defining the size of the bed and the build volume, but changing them does in fact do not solve your problem. Your problem is that you need to address where the sensor may probe within that specified volume i.e. the sensor probing area.

I use ABL (Auto Bel Leveling) on my Anet A8 using a left-front mounted sensor at position (x = -26 mm; y = -40 mm seen from the nozzle center). In order to have the sensor on the bed area without running into the limits of the carriage, you have to calculate (yourself!) what the dimension of the auto bed leveling area is. This is because the sensor is off set from the nozzle. If the sensor reaches for the whole bed, you need extra space on the axis. To explain this, if your sensor is at the left front, as in my case, the amount of extra space you have left on the right side of the X carriage will determine how far the carriage may go and thus limits the right probe position. If there is no extra space on the carriage (the safest assumption) you just need to add the sensor offset to the maximum bed size (what the nozzle can reach). E.g. my probe X offset is -26 mm. The maximum probe distance is therefore -26 mm + 220 mm = 194 mm.

This means that you need to set the following constants (amongst the settings to enable ABL; the probe and the type of leveling...) in the configuration.h of your Marlin Firmware installation:

#define X_PROBE_OFFSET_FROM_EXTRUDER -26   // X offset: -left  +right  [of the nozzle]
#define Y_PROBE_OFFSET_FROM_EXTRUDER -40   // Y offset: -front +behind [the nozzle]

// Set the boundaries for probing (where the probe can reach).
#define LEFT_PROBE_BED_POSITION (0 + 10)         // 10
#define RIGHT_PROBE_BED_POSITION (220 - 26 - 10) // 184
#define BACK_PROBE_BED_POSITION (220 - 40 - 10)  // 170
#define FRONT_PROBE_BED_POSITION (0 + 10)        // 10

Furthermore the settings you do mention need to be:

// 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 -33 // Distance from end switch to X = 0 of origin
#define Y_MIN_POS -10 // Distance from end switch to Y = 0 of origin
#define Z_MIN_POS 0
#define X_MAX_POS X_BED_SIZE
#define Y_MAX_POS Y_BED_SIZE
#define Z_MAX_POS 240

The -33 and the -10  define how much the nozzle needs to travel from the endstop position to the print origin! This is not necessary to change when using ABL with a sensor (unless you are using a different print head carriage with a different center of the nozzle). Why these values are -33 and -10 (or values close to this; e.g. for my printer they are -36 and -8) is explained in this answer.


All-metal hotend, cooling fan failures, and cold-side PTFE I'm getting a pet bird soon, and I know that off-gassing from heating PTFE above 300 °C creates noxious fumes, which are bird-killer1. To try to prevent even the chance of that I'm replacing my hotend with an all-metal one. I have an E3D v6 1.75 mm, which I noticed still uses a PTFE tube at the cold side (the 3 mm version apparently doesn't, but 1.75 mm filament is what my printer uses, so there we are).

If I'm reading the instructions correctly, it sounds like the heatsink shouldn't even get warm to the touch, and if that's the case I'm not worried as long as things go well. What I'm still worried about is what happens if the heatsink cooling fan fails. I plan to plug the fan into the always-on 12 V port on my board (SKR 1.3): if I do, then is it possible to set my firmware (currently Marlin 2.0.4.4) to stop a print if the fan fails?

If I can't get the firmware to stop on fan failure, then is there a 1.75 mm all-metal hotend out there that doesn't require the use of PTFE on the cold side?

1- Here: "at temperatures above 570°F (300°C), Teflon [PTFE] coatings on nonstick cookware start to break down, releasing toxic chemicals into the air (14)"

First of all, we need to discuss the failure mode and what can be done. LEt's do a
Failure mode 1: coolend-fan stops working.
Let's assume the coolend-fan for whatever reason (cut cable, defect fan, burnt board...) stops working. As a result, the coolend starts to rise in temperature, as it doesn't drain as much heat into the room air as before. This directly leads to an increase of the hotend temperature, which results in a case differentiation:

The hotend does not cope well with the loss of the heatsink and it triggers Thermal Runaway protection as for a given voltage bump the heating gets too high - the print gets aborted before the hotend reaches a temperature above 275 °C.
The hotend does not trigger Thermal Runaway Protection but the controller alters its heating behavior and works the heater on a lower duty cycle. As long as the hotend temperature is ordered to stay low enough, we will get a lot of extrusion problems from heat-creep, but the PTFE seated into the heatbreak stays below the heater break's temperature, as the thermal mass of the coolend alone draws away thermal energy into the room, even without the fan that keeps it at room temperature. As long as you don't print at above 300 °C and the thermosensor is intact, the failure mode does not release any fumes that could result in Polytetrafluoroethylene Toxicosis.

Failure Mode 2: coolend fan stops Working, no TRP, Thermosensor OK
But what if TRP is off? Let's look at this Double Failure: The hotend does not trigger Thermal Runaway Protection (or it was turned off to begin with) and the temperature increases due to the lack of cooling from the coolend.
As the hotend reaches 275 °C (few printers print that hot, and they use specialized setups), it should trigger the next safety line: a MaxTemp error and cut power. Heating stops before the coolend gets to the dangerous zone of 300 °C, as the coolend always is less hot than the heater block.
Failure Mode 3: no TRP, Thermosensor broken
We are getting desperate and turn off TRP, then break or disconnect the thermosensor to get a static low temperature. NOW we are getting serious, as only with such a failure we can trick our controller to continuously heat the heater cartridge and not trigger any of the error conditions. Only now there is the mere possibility to heat the coolend over 300 °C.
Marlin Firmware is designed to carefully work with checks and balances to keep the heater block in the wanted margin, and it would need a deliberate manipulation of the software to disable all safety features in conjunction with the failure of the thermosensor for the printer to go into Thermal runaway in such a degree that the coolend goes over 300 °C. And then you have different problems: your printer surely is turning into a molten pile in that failure mode. The presence or absence of the coolend fan would just delay the inevitable, should you run such a fire hazard-machine
Conclusion
Configure and install a recent firmware distribution (Marlin 1.1.9 and Marlin 2.x come with TRP enabled by default) and be sure to have MaxTemp enabled at 275 °C and Thermal Runaway Protection on, and you have a 3-layer safety against PTFE-fumes.
Adding more layers surely is possible, but the cost-effect calculation gets worse starting there.


Can I reuse 3D printed parts? I need to show a demo to people on a daily basis. But every demo is for a different 3D printed part.

Can I reuse the material? Is yes, what is the maximum number of times that the material can be reused?

I ground up some prints and extruded them into new filament. The quality of recycled filament is not very high so I would not recommend it.

As pointed out earlier, the shredded bulk material you would create from your old prints would cost more in time and energy to produce than buying new raw material (pellets, not filament), and you still need to extrude it into filament to be able to use it in a printer.


Is there a way to get more horizontal coverage out of "Vase Mode" in Simplify3D? I like using "Vase Mode" (or single outline corkscrew printing mode) for quick nonfunctional prints, but it tends to leave gaps in horizontal or near horizontal surfaces. I understand why it does this, but is there a way (beyond printing with no infill*) to get a little more horizontal coverage out of it?

*Is the answer to this literally just "Try to print without infill?"

Version 4 allows you to have multi-process vase mode prints -- do the vertical surfaces in vase mode, then switch over to normal mode for the horizontals. This lets you have the best of both worlds in the same print. :)


Printing Filatech PETG with HyperCube E3Dv6 Clone fails after 3 smooth layers Recently I got a PETG filament from Filatech to print with my HyperCube printer with E3Dv6 clone Hotend. First 3 layers for every print are pretty fine but 4th layer doesn't stick and my prints fail like the picture below:

I use the following settings:

Slicer: Cura with Generic PETG profile
Hotend Temperature: 240 °C
Bed Temperature: 70 °C
Fan Speed: 100 % at the second layer
Print Speed: 50 mm/s (first 3 layers @ 30  mm/s)

I also tested 225 °C and 250 °C hotend temperatures. Both failing at the 4th or 5th layer. What is the issue here?

BTW I successfully printed with ABS and PLA with this printer.

As this is material dependant, you are facing not a printer, but a settings issue: your slicer needs the right settigns to print PETG.

The first layers look good, but then we get signs of stringy printing. Stringy printing usually happens if the filament comes out of the nozzle too cold (I had tried to print PLA at 170 °C and it would look somewhat similar) or if it gets cooled or stretched too much (forced a print failure by speeding up a 60 mm/s print, somewhat similar around 250-300%; though the filament was not hot enough then too). This, in conjunction with the information, that you print PETG suggests the following things to fix:

Reduce or deactivate cooling. PETG often doesn't need cooling at all.
Reduce print speed. As 0scar said, 50 mm/s is a good upper limit on a well honed in machine. As your other layers with 30 mm/s were fine, you could possibly go down to 40 mm/s, if less cooling alone doesn't help.


BLTouch with TH3D Ender 3 pro I installed TH3D to my stock mainboard via this guide, but BLTouch does not work properly.

It does not check all 9 points before point it just go middle then check z then start printing. BLTouch normally needs to check all 9 points before printing or with autobedleveling but somehow mine do not work like this.

After setting up the BLTouch in firmware, you need to activate the leveling function for every print by inserting the leveling G-code 'G29' in the start G-code script of your slicer. The code should be placed directly after command G28.

Note that you can test the working of the sensor from the printer display: sensor can be deployed, stowed, reset and tested.


Could anyone please provode me settings for Custom FFF for Zonestar Z6FB printer Recently I bought a printer and failed to find Cura 4.8 settings for it (both in application both myself). My printer Zonestar Z6FB
Currently I doubt in:

G-code flavor
All printhead settings excluding extruder number (which is obviously 1 in my case)
Start/End G-code

Add printer image to eye trap someone who also interested

After some pain, I figured out that if you are a poor Ubuntu/Linux user you should only use the AppImage version of Cura which you can download from official website
Next, make the file you downloaded executable chmod +x *.AppImage
Next, start it from terminal or by clicking in navigator
Ok, proceed as is and then Help ▶ Show Configuration Folder.
It will show 2 folders we need ~/.local/share/cura/4.8
Ok now download ZONESTAR_Cura_Resources.zip from here.
Then copy all files from ZONESTAR_Cura_Resources TO ~/.local/share/cura/4.8 but remember that directory structure is messed up but can be figured out.


CR-10 randomly pauses for a few seconds I thought I have already had and fixed every problem one could possibly have with a 3D printer. Guess I was wrong.

I haven't used my Creality CR-10 for a few weeks, everything was working the last time I tried. Today I wanted to print something minor and the printer just randomly paused a few times in the middle of the print.

To be exact, it seems that after a few G-code commands have been executed the printer just freezes for like 10 seconds and then continues like nothing happened. This occurred a few times and every time the nozzle is melting the surrounding plastic and extruding a little which ruins the print.

I have tried:

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

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

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

This is a known issue with Cura 4.1 when z-hop is enabled.

If you touch the z-axis motor frame while it is apparently stationary, you may feel it is actually moving.

The solution is to set a value (I used something like 250 in conjunction with an Ender 3) for the "Maximum Z Speed".

First you need to get the setting to be visible, so go to the "Settings" menu and choose "Configure setting visibility...":

Then in the "Print settings" panel:

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


Scale down SketchUp live size object does not render completely I got a life size model of a signaling post (trains) where I scale it down to 1/87 model (in SketchUp). When I send the model to my 3D printer (with Cura 2.4) some parts of the model are lost in translation even when their dimensions exceed the printer minimal dimension of 0.7 mm.

Is this a known problem of Cura or is something else at hand?

You will indeed have difficulties with scaling a model to the point that individual components become smaller than the tolerances of your printer.

It is more likely a problem with your model, having been created in SketchUp. If you use an online model repair service, it will almost certainly return an indication that the model was flawed. Unfortunately, those repair services are not a good choice for repairing a SketchUp model, as the fail points are usually beyond the capability of the software.

Another option would be to load the model into MeshMixer and use Analysis/Inspector to reveal the flaws, but again, the automatic repair feature would likely destroy the model.

Even a program as simplistic as TinkerCAD will do a better job of creating a 3D printable model.

Consider to begin learning a different, perhaps more challenging program such as OpenSCAD or Solvespace, or even more challenging than those, Fusion 360. All of the above are free, while Fusion 360 has the requirement of non-commercial/hobbyist use to remain free.


Wrong calculation of E-parameter values Hello dear Community,
I am trying to print my first Box and I have a problem with the skin of the bottom layers.
After finishing the slicing and while looking into the generated G-code I was wondering why Slic3r increases the E-parameter continuously when 90 % of the lines have the same length and the axis have the same speed. Logically as long as the length of the lines are equal and the speed of the axis is also fixed so the amount of extraction has to be in this case also fix but that is unfortunately not the case.  Therefore as you can see in the Result photo, that the printer prints the skin layer at the beginning in the right way with the right amount of extruded material. At the end of the skin layer, it seemed very bad because of the huge amount of extruded material.
Some Infos about my Printer may be interesting for you :
Nozzle diameter = 2.7 mm
Type of Filament= granules
Diameter of filament = 2.5 mm
Please let me know your suggestions and feedbacks.

The value you see is the cumulative extrusion, in other words the E value in consecutive G-code commands reflect a position of the filament since you started that print.
It is normal that it continuously increases in "absolute" mode.
You should see, at the beginning of the G-code, also a M82 or G90 command, which means "absolute extrusion". And you should avoid having M83 or G91 later in G-code, which would change an interpretation of E values to "relative extrusion".
It is more accurate than relative extrusion (which is the mode you are thinking about).
From your print it looks like the printing bed is not properly tuned, probably too far.
Also, it is difficult to see properly, but it looks like you get bubbles in the second part of the print, which are the reason there is an increase of extrusion: hot air pushes too much filament out.
Maybe your granules are not properly dry. It is difficult to tell you more, pellet extruders are more difficult to tune than filament extruders.


Disable Marlin PID, and start print manual The thermistor of the hotend of my printer broke, at the moment I have no way to replace it, due to the global situation with the virus.
In my hands I have one of these industrial PIDs which is Temperature controller+K-type couple+SSR.
Is there a way to disable the PID in Marlin and start printing manually when the PID reaches the desired temperature? I just need it for PLA right now.
This way I can use the printer at least until I can replace the thermistor

You can edit the temperature control commands out of your gcode, or just tell your slicer to omit them, typically by setting temperature to 0. Then, as you suggested, start the print manually once your industrial PID tells you it's at-temperature.


Cura's solution to replace corners->arcs to increase corner speed? I realized that with current Marlin I cannot use Junction Deviation with Linear Advance, see [BUG] Rapid changes of acceleration break linear advance when using Junction Deviation #15473.

Yet, it is very much beneficial to not stop at the corners with high acceleration but rather do a small curve. Is it possible on a G-code level?

Is there a feature or plugin in Cura which replaces sharp corners with arcs to remove need for Junction Deviation in firmware?

Cura's solution can be found in the "Jerk Control" settings.

Short analogy; when driving, and a corner is coming up, you basically have two options to take the corner smoothly; you can take the corner with a wide turning radius, or you can slow down. Taking a neighborhood street corner at highway speeds just doesn't work even if there's nobody else on the road; you'll very likely overshoot the corner, if you're in a RWD car you'll likely lose the back end and fishtail (or worse), and the occupants of the car, yourself included, are going to be thrown around violently, to no-one's real advantage other than to say you took that turn at 70.

Back in 3D printing land, something similar applies; as the extruder approaches a sharp corner, it will be disadvantageous all around for the extruder to try to maintain 70mm/s around what's basically an instantaneous turn. Your jerk (stopping the moving axis) and acceleration (starting the non-moving axis) settings are going to exceed the physical capabilities of your steppers and drive belts, making the corner less accurate (and in the extreme, losing steps causing layer shifts), and if your belts are not perfectly tensioned, and really even if they are, you'll get "ringing" (the 3D equivalent of fishtailing as you straighten out after the apex of a turn while driving).

The first option, cutting the corner, is your corner-to-arc replacement; rather than try for an instantaneous turn, just soften that corner by enough that you're within what's possible for the stepper motors in terms of acceleration. This keeps the speed and surface quality high, but necessarily reduces the accuracy of the print to the model.

So instead, Cura encourages the second option; slow down before the turn. Enabling Jerk Control and tweaking the associated settings lets the Cura slicer reduce head speed gradually as the extruder approaches a sharp corner, thus reducing the torque required to stop motion in one axis and start it in another, to something the steppers can actually accomplish at a rate you'd call "instantaneous". This keeps the corners sharp and avoids ringing along straight lines after a corner, at the cost of a slower overall print speed (though not as much as reducing overall print speed to the speed at which the extruder will take corners).

Now, I realize that this is the opposite of "increasing corner speed"; jerk control exists to slow the extruder near corners. However, increasing corner speed is rarely what you actually want, for the reasons stated above. If you really want nicely-rounded corners, fillet them in CAD, and then the slicer will generate a sequence of arbitrarily short linear movements (true G2/G3/G5 curve interpolation from the purely polygonal STL geometry has been experimented with, but currently more trouble than it's worth) which limit the change of velocity of the extruder as it rounds the corner, instead of making the rounding an "artifact" of printer limitations. At fine enough detail levels of conversion to an STL, the results are indistinguishable from a true curve.


Why is a heated bed important? I hear that heated beds can help with removing finished prints, but not all printers have them!

Is this a nice to have or must have feature?
Are there any downsides to heated beds?

I'll try to give it a shot as the other answer (perfectly sound answer b.t.w.) does explain "how" we use heated beds, but not "why" they are actually needed for good prints.

Plastics or polymers are mostly amorphous (no macro crystalline structure) and usually relatively hard and brittle at low temperatures (this is referred to as "glassy"). By increasing the temperature of the plastics the state of the material changes as it becomes soft and more ductile (called the viscous or rubbery state). The temperature at which this transition takes place is called the "glass transition temperature". It is this temperature where you would heat your bed too (or close to this temperature). Below the glass temperature, the expansion is reduced/low because the polymer chains cannot move easily due to the closer packing and stronger inter-molecular forces; increasing the temperature increases the expansion lowering inter-molecular forces. The difference in stress between the bed and your print is therefore reduced (as of the expansion  of the heated polymer).

This explains why we use heated bed to get the prints to stick to the bed. To answer your question why it helps in removing prints is that when the temperature is lowered, the polymer gets back into its "glassy" state, shrinks a bit and automatically loosens the print from the bed.

Indeed for printing PLA you can print without a heated bed, but for materials with a higher glass transition temperature and higher printing temperature it's almost a must to have. Downsides of heated beds are that they require a lot of power and when improperly installed lead to burned wires and connectors. It's usually wise to strain relief the wires from the bed and use proper gauge silicone leads and connectors.


Can you recommend professional 3D metal printing books? I am a fresh graduate student in 3D metal printing. My undergraduate major is mechanical engineering. Later research will focus on the process of metal 3D printing. I hope that you can recommend some excellent 3D metal printing books for learning.

This is a free ebook that I have perused briefly which it looks interesting, and it is free (did I say that already?)

3D Printing of metals

Manoj Gupta
ISBN 978-3-03842-591-5 (Pbk);
ISBN 978-3-03842-592-2 (PDF)

Three other books that might be of interest are:

3D Printing with Metals for Design Engineers, Explained

Ann R. Thryft
Downloadable free ebook, but some sort of sign up is required

Additive Manufacturing of Metals: The Technology, Materials, Design and Production,

Yang, L., Hsu, K., Baughman, B., Godfrey, D., Medina, F., Menon, M., Wiener, S.
ISBN 978-3-319-55128-9

Additive Manufacturing of Metals: From Fundamental Technology to Rocket Nozzles, Medical Implants, and Custom Jewelry (Springer Series in Materials Science)

Although, as the title contains a (rather obvious) mis-spelling, it does not bode well for the rest of the book.
John O. Milewski
ISBN-13: 978-3319582047
ISBN-10: 3319582046


Internal wall does not print in horizontal print orientation I have an object that has cutouts in it (alignment pins fit in the cutouts). The shape of the hole is a right triangle with the point clipped off to create a flat surface in the deep part of the hole.

When I print the object in vertical orientation the wall in the deepest part of the cutout is printed properly. But when I print the same object laying down flat on the build plate, the internal wall is not printed and I can see the infill grid through the hole where the wall is supposed to be.

I sliced the object with a slicer based off a recent Cura version. I'm using the same STL to print the object vertically and horizontally.

Why is this occurring? Is there anything I can do about it other than printing vertically? (Because I have a need to print the real part horizontally. The part shown here is just a thin test piece.)  Thank you

Here is a picture showing what the (Cura-derived) slicer does with the model in horizontally-printed position. I checked the layer display in the vertically-printed instance, and the missing wall was correctly rendered and visible.

I guess this is some kind of a slicer bug.

Here is a large-scale picture of what the cutout shape looks like. This picture is of the protrusion tab that fits into the hole. But the same shape was used to cut the hole in the object.

Here is another instance of the same problem. This time, I made up a simple block component, a simple cylinder component, aligned the cylinder into the block volume, and did a combine/cut operation in Fusion to cut a hole in the block (visible in the STL file). As you can see from the (Cura-derived) slicer layer image below, the same problem exists - no wall at the back of the cut when printing in the horizontal position. If I draw a sketch on the block and extrude/cut into the block, I get the same results. I also tried cutting the cylindrical hole, creating a "tin can" shell cylinder with an explicit bottom-of-the-can surface, sliding the open can into the cut hole, and joining the can to the block. Same results. The explicit bottom 0.5 mm surface of the can disappears in the horizontal slicing position. Strange.

UPDATE:

The test object is just a simple block with a cylinder extruded into the block as a cutout. As simple as simple can be. I have determined that Cura 3.5.0 works properly (Cura v3.6.0 is available).

I am using the Qidi slicer v5.0.7 latest, which uses an earlier version of Cura (I don't know which one; I have sent them an email to find out).

I have determined that the Qidi slicer behaves properly if the cutout cylinder diameter is 6mm or larger. But at 5mm, the slicer will not generate a back wall in the cut. The square/triangular cutouts in the example objects below are all 5 mm or less. My installed Cura 3.5.0 generates a proper back wall even at 5 mm. Therefore, it must be a bug in the Qidi slicer, which uses an older version of Cura.

As a workaround, I will increase the size of my cutouts to 6 mm. When Qidi updates to a newer version of Cura (they are currently using 3.3), the problem should go away.

I think this is caused by the shape of the hole. The shape is parabolic or circular, this means that if you slice it as in the green part, the slicer determines the placing of the layers along the curvature. If it has a shallow curvature, and slicing layer height is relatively thick, the curvature of the object cannot be followed. But, if you have more than 1 top layer, this usually should not be visible. I don't think that you have a single layer, so this is a pretty odd anomaly that I have not seen yet (that you look at the infill without top layers).

You could get past this by using a local different infill, e.g. 100 % infill. You can look at this answer of the question: "Different infill in the same part". This should help you out printing in your preferred orientation.


How to thin UV sensitive resin I have some older resin that got a bit thick. I was thinking I could use some paint thinner to thin it a bit and restore it. My thoughts are the paint thinner is made of terpene oils so should be compatible with the resin.

To test, I went ahead and mixed a half capful of paint thinner with about a cup of resin. I mixed it thoroughly and it seemed to mix well and restored proper viscosity. I then filtered it through a paper coffee filter twice. The results were very nice and smooth resin. I did a UV hardening test with a few drops on a strip and into the UV lamp. It still hardens.

Any thoughts, suggestions or OMGs! before I try this in my printer? It's a Pegasus Touch SLA.

You've covered a couple of concerns "outside the box," but the real tests will come when you pour some of the resin into the vat.

If you don't get a reaction with the release layer, score one for your side. The release layer is a silicone kind of compound, which typically is un-reactive to most substances, but that's not to say the thinner qualifies in that respect.

To be cautious, you could dab a bit on the corner of the vat, especially out of the usual scan area or off the build plate contact surface. If it sits without clouding the release layer, the next test would be a layer test.

You could even remove the build plate, pour the modified resin in the vat and run a model comprised of only one layer, perhaps two. You'd be able to carefully pull the cured resin off the release layer and make a preliminary determination.

If all is well by this point, it's time to create a model, yes?

I hope you'll report back on your results. My Pegasus is still in the box from Kickstarter days. I'm sure my resin is well beyond the "sell-by" date!


Installing Slic3r on Kubuntu 14.04 with NVIDIA I am running crazy trying to install Slic3r on my Kubuntu 14.04. It is a fresh Kubuntu and I downloaded the Slic3r package from them.

At first it worked well but then I changed the display driver to NVIDIA instead of the default Nouveau. I have repeated this operation a couple of times and I am almost sure that the NVIDIA driver screws up my system.

I have read and followed several "SOLVED" posts but none of them gave me a solution.

Any ideas?

There is a huge problem with any linux distributions and Nvidia drivers. I have tried countless times to get that driver to work but it crashed my systems time after time. If your slicer works with the default driver i would not try to change it. If it doesn't then you may have to go to windows where the driver is guaranteed to work. I know this is not the answer you are looking for but unless you can code a new driver to work for Linux thats the only solution.


Will a Micro Swiss extruder and hotend speed up prints on my Ender 3 Pro? Long story for hopefully a simple yes/no answer:
I have a lightly modified Ender 3 Pro (BLTouch, glass bed, beefier bed springs and nobs, led lights) and I daydream about someday getting an "Ender Extender" kit to go larger or something, but before I ever do that I need to drastically speed up the prints.  Last night the first layer on one of my prints took 40 minutes and I watched the whole time to make sure it laid down well.  Can't imagine waiting around with a larger build surface.  I understand basic settings like lighter infill/less perimeters/etc... but when it comes to really changing the speed and acceleration settings I'm a bit of a newb.
So after reading this article on improving print speeds, it seems like the Bowden tube style default extruder on my Ender 3 probably doesn't have the grip strength and/or constrained filament path to really push filament faster.
Based on that same article and this one, it seems like there are a lot of options for extruders and hotends to upgrade.  The reason the Micro Swiss appealed to me is that it seems like this option is pretty much bolt-on plug and play (additional info here).
And it seems like it already has a convenient spot for my BLTouch.
Which brings me to the title of my question:  will that Micro Swiss extruder/hotend combo do what I think it'll do?  i.e. allow me to push filament faster and heat it up quicker?
Is there a better alternative extruder/hotend that is also pretty easy to figure out?
Lastly (maybe this should be a different question/too open-ended) are there other relatively simple upgrades/modifications to the Ender 3 Pro that will help it print faster?

If you want a single word answer, then no.
Before you ask this question you need to figure out why your prints are slower than you want them to be. With default settings, unless your models are something dead simple like a big cube or cylinder, you're almost certainly limited by acceleration, not extrusion rate or even max print/travel speed (which you'll almost never achieve). Gcode analysis tools like gcodeanalyser.com will help you gauge this by predicting actual speeds the printer will achieve. Note that even if your model is simple, printing infill and top/bottom layers involves a lot of acceleration/deceleration cycles, so even for simple models this may still be your limiting factor.
Until you reach very high accelerations (over 5000 mm/s²) letting you actually achieve very high speeds (over 150 mm/s or so), the only way to make extrusion your limiting factor is by using really thick layers or wide walls. At 0.2 mm layer height and 0.4 mm line width, even a sustained 150 mm/s is only 12 mm³/s volumetric extrusion rate which is high but reportedly within the capabilities of the stock Ender 3 extruder and hotend (but probably requires cranking up the temperature).