text:
Uniform squishy infill
I try to print a stamp with flexible filaments. The problem I encounter is that the filament is flexible, but not soft. This leads to small differences in height to parts of the stamp not working.
One solution would be to add a small 'cushion' to add some squishyness to the stamp. I designed the stamp and the 'cushion' but now the question arises:
"Which infill will provide the best uniform squishyness (in one axis)?"
I did a test with cubic infill of Cura, and although it becomes quite squishy, some parts are squishier than other parts of the block.
TLDR; Trying to print a squishy cube, where in one axis all areas of the cube have the same squishyness.

As the rubber stamp needs to be soft in one axis for the whole area, you could use an infill that causes the same softness in all directions, but is sliced as such that the stamp experiences the same softness. Alternatively you can use the specific infill types for flexibility, but beware of the orientation:

Concentric
Cross
Cross 3D

First, to get the same softness in each direction you need to use an infill pattern that has similar/uniform properties (isotropic) in all dimensions.
It is suggested to look into the infill type called "gyroid" (see question What are the advantages of gyroid infill?).
This type of infill is described as:

Gyroid infill is one of the strongest infill types for a given weight, has isotropic properties, and prints relatively fast with reduced material use and a fully connected part interior.

Second, since the stamp has relief, slicing the part may cause different infill height. You could look into Different infill in the same part to e.g. get a solid infill for under the relief to get a uniform infill for the "cushion".

The main problem with Gyroid is that it has been designed for high 'strength' applications. It mainly excels in compression tests (which is highlighted by the links you provide), which is exactly what we do not want. I think for this we need something like a rotated wiggle pattern.

@EDoe No, not if printed in flexible filament! Note to not use a very high infill percentage! Look up the examples on internet for examples how flexible parts you get. I've seen fantastic flexible results.

Sinusoidal infill provides great squishiness in the infill direction, but you'll still have the problem that where the infill meets the perimeter wall, it'll be less squishy than where the perimeter wall isn't touching any infill. You can reduce this effect by using a stiffer filament for that wall (if you can print with multiple filaments), by adding more perimeters, and by reducing the gap between infills (i.e. increasing the infill density). You can even explicitly design an extra-thick wall on the face that takes the pressure (the engraved face of the stamp), and then a section behind that with the squishy infill.
TBH, I'm not sure that flexible filament is really what you need for a stamp. Soft materials are commonly used for traditional stamp-making more because they're easy to etch than because the stamping works better that way. Print-making uses wooden or metal plates (the equivalent to the stamp) and produces better, more repeatable images than rubber stamps. When you're printing a stamp, you don't need to etch it, so the softness of rubber isn't an advantage for you. My outsider recommendation would be to try using a normal, rigid filament, and sand the surface to the smoothness you need. If you print with the stamp face on the bed, and your first-layer quality is really good on a smooth build plate, you can probably get better results without sanding.

authors: ประสิทธิ์ คําทุ่น


text:
BLTouch wiring and pin assignments
I’m in the process of installing a BLTouch on a Velleman Vertex K8400. The board doesn’t have a dedicated servo pin, so I’ll assign one. No problem there.
The board only has a Z-min pin, so it’s my understanding that I’m supposed to unplug my Z-min cable and plug the BLTouch into the Z-min port.
My question is: "Can't I assign another unused pin as a Z-max, plug the BLTouch into that, adjust the firmware, and leave the existing Z-min sensor plugged in?"
Upon further review, I probably shouldn't have said Z-max, and will be more specific.
This is a Mega 2560 board with 2 available PWM pins. Anything wrong with this setup?
Pins.h:

  #define SERVO_0_PIN 15 //PH3 (PWM)

  #define Z_MIN_PROBE_PIN 16 //PH4 (PWM)

Configuration.h:

=======Z Probe Option=======

  #define Z_MIN_PROBE_ENDSTOP

  #define BLTOUCH

I want be able to keep my Z-min sensor plugged in as a backup to prevent a bed crash just in case the BL touch doesn't trigger. From what I see this should work as long as I make sure the BLTouch triggers before the Z-min. Any issues that anyone can see?

Did you install bltouch on k8400? I have the same printer and want to install auto bed leveling but I dont know how

@Ofitecno - Hi and welcome to Stack Exchange. Please ask a new question - questions posted as an answer aren't permitted. Please take the [tour] to get a better understanding of how SE works. Thanks.

Note: The question has changed after posting this answer. This answer answered the previous question, but is now out-of-date with respect to how the question has changed; I'll update it later, as it is possible what is asked now.

You can change the Z-min and the Z-max pin assignment in Marlin Firmware in the pins_<boardname>.h file, you basically exchange the Z-min and the Z-max. Note that the switch connected to the old Z-min port now becomes a Z-max sensor if you enable that in the firmware; you should therefore remove it (the actual switch) from the minimum Z position.

To enable a BLTouch sensor you require 2 pins free on the microprocessor. One registers the signal of the trigger, the other triggers the servo to stow/deploy the sensor.
You can connect the white/black to the Z-min signal (Z-min pin) and ground of the Z-min connector (or if pins are swapped in the firmware to the Z-max). The other wires need to be connected to +5 V (red), ground (brown) and orange/yellow to a free analog pin (PWM pin):

BLTouch can be operated in the following condition.
  - One I/O for control (PWM or Software PWM)
  - One I/O for Zmin (Z Probe)
  - GND and +5 V power

The PWM pin should be defined in your pins_<boardname>.h file, e.g.:
#define SERVO0_PIN         5 // RUMBA board

or
#define SERVO0_PIN         27 // ANET board

The Z-max signal pin is no PWM pin for the servo.

After studying the Marlin code, I found the answer I was looking for.
If I have a spare PWM pin, I can assign it to anything I want. So the best solution is to define the pin as a Z_MIN_PROBE and then in Configuration.h in the Bltouch settings
#define Z_MIN_PROBE_ENDSTOP

rather than
#define Z_MIN_ENDSTOP_USES

source: Stack Exchange

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

sort: votes


text:
How to decrease sensitivity to heat-bed temperature?
Sometimes I use a DIY 3D printer running Marlin firmware and I have a hard time to set my heat bed temperature. when I set it to 70 °C for PLA, after a few minutes it decreases to 67 °C and I see these error:
READ: Error:Thermal Runaway, system stopped! Heater_ID: bed
READ: Error:Printer halted. kill() called!

Since then the communication with printer is lost, the printing process stops and I have to reconnect to serial port... It's a disaster. I guess I need to lower the sensitivity to 3 degrees at least. I don't know how!?

Have you PID tuned the heated bed?

aside note: as an upgrade you can add an insulation under your HB to keep the temperature more constant

@0scar No, I'm using the default pid parameters. I Thought it would mess it up if I changed them.

@ darth pixel , I'm using an insulator, however it doesn't cover all the surface beneath HB.

First thing to do is do a PID tuning session! :)

I had a similar issue when printing with ABS, because my print cooling fan only activated once it got to a certain height above the bed. I'd say you need to do a PID tuning session, insulate the bottom of the bed better, and see if you can make sure your cooling fan doesn't blow air over the bed itself.

Thank you.  Since I did a pid tuning session everything is good.

For people from google:
Go to configuration_adv.h in the marlin firmware source code, and search for "THERMAL_PROTECTION_HYSTERESIS". Then increase the number. The number is how much degress celsius the temperature can be off before thermal runaway

This is the correct answer to the question that was asked. While the solution to the OPs problem was pid tuning, this is the correct place in Marlin to change the number of degrees off before triggering an error.

@agarza this config changes the sensitivity of the thermal runaway. so its exactly what the op asked

Ok, I see now. This is basically a "how to fix it in code" solution. Learn something new everyday. Thanks for enlightening me.

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


text:
MKS GEN L looks dead
In an attempt to upgrade my Ender 3 to TMC2208, I bought an MKS GENL 1.0 board from Banggood, but it doesn't get recognized from the Windows Device Manager at all: no COM port, no "Unknown Device", no beep when connected/disconnected via USB.
I have some Arduino and electronics experience and having an USBasp I've decided to give a go to reflashing the bootloader, with no joy. I tried flashing both the stk500boot_v2_mega2560.hex and the ATmegaBOOT.hex using avrdude like the following (copy pasted from Arduino IDE):
bin\avrdude -Cetc\avrdude.conf -v -patmega2560 -cusbasp -Pusb -Uflash:w:..\..\arduino\avr\bootloaders\atmega8\ATmegaBOOT.hex:i -Ulock:w:0x0F:m

Whatever I do the board seems dead: tried alternative cables (also double checked using a plain inkjet printer to confirm it wasn't that) and also alternative PCs (all running Windows)... I believe it might be possible for me to upload Marlin via ICSP, but without USB I'll have not much use for it anyway...
It might be worth noting the board uses a CH340 USB chip (drivers already installed), which seems to be getting only 2.6 V at VCC...
When connected via USB the red power on LED D7 turns on, but nothing else happens...
I'm about to throw the board into the bin and buy another one from Amazon, unless somebody has any suggestion that might revive it...

You might need a CH340 driver to be manually installed, although Windows normally installs that for you (whereas for OSX it is much more of a nightmare). See this for example, although, I presume (from your description) that Windows isn't even showing you an unknown device in Device Manager?. What is the error (if any) that you get when using avrdude? I've had issues like this before, and I've always been able to get them going again, usually with judicious use of the reset button and timing it just right.

CH340 driver is installed, but as windows in not recognizing ANY device I have no COM port to specify to avrdude. The usbasp bootloader programming via ICSP seems to complete nicely (both write and verify steps completed).
I would generally agree with you with regards to resetting the board, but in this case it seems it's the CH340 being gone...

Hm, it doesn't sound good. This is a bit of a long shot, but the only thing that I can think of (at the moment) is to carefully monitor Device Manager whilst plugging in the board, and/or resetting the board. I had a mis-behaving Arduino-clone once that had a icon flash up only momentarily in the device manager (upon reset or plugging in) and if you weren't actually watching the device manager at the time you would never have known that it showed up briefly, and then disappeared. See here & its sequel.

Presumably you've seen this: Mks Gen L and nothing! (where the solution appears to be buy a new board!) and more promisingly Marlin compile and upload fails–MKS Gen L 1.0 (SOLVED) - among the many hints and tips, possibly there is a need for a CH341SER driver (rather than a CH340[G])?

@Greenonline the alt driver didn't help either, as I was expecting due the fact no device shows up to the device manager, not even momentarily. I also went a little to a lower level, trying to use zadiq to scan for any device having any USB signature, but the only USB devices recognized are those I already know (mouse, keyboard, USB hub, etc...)
I would definitely rule out the driver problem at this stage... But thanks a lot for providing all that info and links

OK, fair enough... :-) Like I said it was a long shot. I've just had a CH340G nightmare this evening, but yes, at least my board showed up, as unknown in the USB list in Device Manager - whereas yours isn't. Well, I'm out of ideas, I'm afraid. Good luck to you anyway, but yeah, sounds like the board is toast. :-(

What do you mean by: "it might be worth noting the board uses a CH340 USB chip (drivers already installed), which seems to be getting only 2.6 V at VCC..." Where are you measuring VCC, and how are you powering the board when you make this measurement?

Powered from USB and measuring between GND and VCC pins of the integrated circuit


text:
ASA and BVOH adhesion
I am printing a mechanical part for my printer.
It's a new mount for my extruders and I have been attempting to use BVOH as a support filament so that when my print is done it will cut down on the need to finish the part and possible mistakes.
My problem is I can get the BVOH to adhere to the bed with no problem and no warping of any kind, but I can't get the ASA to adhere to the BVOH supports. I run the BVOH at 220 °C and the ASA at 250 °C with my fan at 10 % and I am using a Flashforge Creator Pro printer which is mostly enclosed.
Does anyone know of a way to get the ASA to adhere to the BVOH?

Did you read anywhere that this was possible in the first place?

Prusa3d recommends BVOH as a water soluable support material.

Can you tell by looking at the de-adhesion what isn't sticking?
It may be that printing the ASA at higher temperature is melting the BVOH enough that it doesn't stick, being molten.  If so, then it may be possible to print the first layer of ASA at a cooler temperature, slower if necessary to still succeed at extrusion, with fans blowing.  Then, print the next layer of ASA at a higher temperature, also with fans flowing.
A test might be to print the BVOH, then a layer of ASA, and stop.  Let it cool and test the adhesion.  If it sticks under these conditions, then a better command of the temperature profile may offer a way forward.

or... just make the interfaces BVOH

Here's how I got it to work. I set the heat bed to 110°C and disabled the underlayer of the raft layer. I set the BVOH and the ASA to 235°C after the 4th layer I set the heatbed to 90°C  and after the 6th layer I set the bed down to 60°C so that the BVOH hardened and adhered to the bed making sure that nothing curled or moved. After the print finished it took 24 hours for my BVOH to fully dissolve but thats probably because I set my support to 100% infill. Either way I got a perfect ASA extruder mount


text:
Printer LCD controller required when using a Raspberry Pi + LCD?
When using a Raspberry Pi and an LCD to run the printer, can the LCD controller that comes on the printer be removed or does it need to be used also?

Why remove it?  It's not in the way and it's hardly a power pig.

@CarlWitthoft Those flat cables are generally in the way when you want to nicely route the cables for some proper cable management... ;)

No, when you run the print jobs from a Raspberry Pi, e.g. using the OctoPrint print server, you do not need the display of the printer as you can control the printer from the Pi screen or from a browser of any other device. Do note that not all functionality of the LCD controller is built-in in those printer servers, but you normally have a terminal to interface using G-code with the printer, or you can make macros to do that.
In some cases it might be handy to leave it on the printer for small adjustments, homing an axis, or feeding some filament; it saves you some time opening a browser to control the printer when you operate the printer remotely and allows to troubleshoot the machine manually.


text:
Why do 3D printers have only one limit switch?
I have seen that many 3D printers have only one limit switch for each axis, how does it know where to stop on the other end?
My first guess is that the machine knows how big the plate is, and calculates it accordingly.
If this is true, then if I were to use a RAMPS, I would have to modify the software to figure out the build plate, it won't have the hardware to autocalculate.

it doesn't need to be at one end, any known position can be used to "home" (calibrate absolute position in regards to future movement commands).

Limit switches have (at least) 2 uses: finding the edge, and preventing running past it. With one limit switch per axis you get the first but only half the second. But as @Oscar points out, any kind of slippage (belt, motor limitations, etc.) means the axis won't be where the software thinks it is. I much prefer having limit switches at both ends.

I believe you can add a 2nd limit switch, and update the Configuration.h file to show it's there.  My combined Mega2560+RAMP functionality (Migbot printer) has both + and - limit switch connectors.  Looks like this, with X+/X-. Y+/Y-, and Z+/Z- at the lower right.  I haven't tried any Config file changes myself, am just running the software that came with the board in Jan 2015.

In principle you only need the minimum axis position (or the maximum), the offset to the bed and the size of the bed in the direction of the axes. Fortunately, you can specify this in the firmware:
E.g. in Marlin Firmware offsets are defined as travel limits:

// Travel limits (mm) after homing, corresponding to endstop positions.
#define X_MIN_POS -33
#define Y_MIN_POS -10
#define Z_MIN_POS 0
#define Z_MAX_POS 240

Bed size:

// The size of the print bed
#define X_BED_SIZE 200
#define Y_BED_SIZE 200

Do note that some printers do have maximum endstops on top of minimum endstops. This is handy in case of layer shifting (e.g. caused by the nozzle catching the print as such that the belt skips notches and as such redefining the reference frame) to prevent the carriage from destroying the printer at the maximum of the axis.


text:
Is the Sparkmaker good enough to print OO/HO small detail objects?
I don't want this to be a specific producer question, but I would like to know if the Sparkmaker is good enough to print small details in OO/HO scale objects.
I'm referring here to objects like furniture, and other house appliances at scale.
I wasn't able to find any visuals with very small objects for this printer.

In general, resin printers can provide a level of detail that has to be viewed with a magnification device. The technology used in the printer will limit the resolution of the printed object. Laser based SLA printers will give the smallest resolution, while LCD panel based printers can be slightly more coarse.
The specifications on the web site for that printer indicate an X/Y resolution of 57 microns, which is 0.057 millimeters. One-sixteenth of a millimeter is quite a high resolution when it comes to 3D models.
According to the 'net HO scale is 1:87, described as 3.5 mm per foot, a peculiar comparison. Directly related to the resolution of the printer, 0.057 mm becomes 0.20 inches approximately. I suspect that an HO scale model does not require one-fifth of an inch detail level.
OO scale is slightly larger and would pose even less of a concern regarding fine resolution objects.

Thank you @fred_dot_u , it is a complete answer. But I think you've looked at their new project. The current version X/Y resolution is 100 microns which I assume is still enough for scale work.

I agree that 100 microns, 0.100 mm still is pretty detailed. Four-tenths of an inch in scale is really really tiny! It means you could have a building with one of those perpetrator door scales and be able to distinguish the inch marks and know how tall is the guy who robbed the stage coach.

H0 comes from "Half-0" and was originally 50% of the 0 track. 00 is a slightly enlarged (4mm per foot) H0, using the H0 tracks.

I own a Sparkmaker FHD whose X/Y resolution is 57µm. Z resolution (layer height) is up to the user, 25, 50 or 100µm being typical values. I have limited experience with it but the level of detail seems to be coherent with the specification.
The more popular (but less powerful in therm of UV light, so slower) Anycubic printers have a 2k screen and reach a X/Y resolution of 47µm. I think some printers with a 4k screen can reach down to 37µm X/Y resolution, even if the practical resolution is probably larger, due to some horizontal light diffusion in the screen upper layers and in the FEP film.


text:
underextrusion of infill?
Running a bency print to test my new cooler, I noticed an odd effect on the rectilinear infill I'm using:

It's almost as if the individual lines of the infill are tearing. The thing is that the actual print turned out great, so the solid layers end up cleaning up the mess and being good. I'm wondering if this is a matter of my infill speed being too fast? I'm running 90mm/s for infill, and the next fastest setting is 70 (i think for perimeters).
Parameters: Tevo Tornado, 1.75mm PETG at 235C, bed at 85C. 100% cooling through the petsfang cooler starting from layer 3.

Reduce the cooling, PETG does not need 100 % cooling. What speeds do you print infill?

Infill at 90. I'll try reducing the cooling.

That is too fast, reduce to 50-60 mm/s PETG does not like being printed fast. Cooling at least half, but depends on the type and effectiveness of cooling. See this answer to a similar question.

Hi there, if this isn't a duplicate and has been incorrectly closed,  please flag as such, and I'll gladly reopen it.  :-)

@Greenonline no worries - thanks. It's close enough, though didn't come up in search.


text:
What is acceptable voltage drop from PSU to controller?
My voltage at the controller at max load is ~11.4 V
(heated bed + motors + hotend). Is this normal?
I'm measuring 11.8 V at the PSU, so 0.4 V -> 5 W lost in the wires.
I have a pretty beefy ~2 mm diameter copper wire that's ~1 m long. Its area is 2.5 mm2. The diameter with shielding is 3.5 mm.
Could there be a bad connection somewhere?
Checked the wire is warm to touch, so looks like it's actually the cause.
Is this normal? Should I go for even bigger wires?

Welcome to 3dPrinting.SE! Is the "~2mm" wire size with or without the shielding?

Measure the resistance of your wire and see if this matches up with your other measurements

2.5mm^2 would make it ~13AWG (13AWG being 2.62mm^2). Per this website, you should see no more than 0.055% drop in voltage over 1m length at 12vdc, with a pair of wires at the size you are talking. I'd suggest at least replace the wiring, if even with the same size. There's some resistance going on there.

Measuring resistance that's <0.1Ohm is tricky.

how do you know that 0.4v equates to 5 watts? are there really 12 amps?

Regardless of how the voltage is lowered, you aren't delivering the power to the heating elements that they are designed to deliver.  For a resistive heater, the power scales with the square of the voltage.
Delivering 11.4 V to the heaters will result in the power being $11.4^2/12.0^2 = 0.9025$ or 90 % of the intended power.
There are two things you could do to increase the power at the heaters.

Your voltage is starting out low, which you may be able to increase
at the power supply to 12.0 V.
The voltage drop in the 1-meter cables can be reduced by using
shorter cables or larger cross-sectional area conductors.  13 gauge
is not a very heavy wire for low-voltage high-current DC.  I would
suggest 10 gauge, and would prefer 8 gauge.

The logic in the controller board should be fine as you are now.  Controller boards include regulators that being the nominal 12 V down to the 5 V or 3.3 V required by the digital logic.  These will automatically adjust for changes in the 12 V supply.
To actually answer your question, the permitted voltage drop is application dependent.  As a rule, though, I would suggest that the voltage on the pins of the controller should be 12 ± 5 %, or from 12.6 V to 11.4 V.  The voltage you measured should be acceptable if it is the true minimum voltage.

Per this website it matches the expectations.
Using 13AWG =~ 2.5 mm^2, 18amps, 12volts, 6feet = 2meters (1m back and forth).
Results in 0.4v drop.

That calculator is set to use the one way distance


text:
Anyone tried Varathane water-based Wood Stain on Hatchbox Wood PLA?
I printed parts for a Harry Potter wand with HatchBox Wood PLA, now I want to apply stain. I intended to try MinWax PolyShades wood stain, then noticed Varathane water-based wood stain is available at my local Rona hardware store. This seems a "healthier" option, maybe not as fussy to apply as PolyShades, anyone had experience with this product?

Welcome to 3dPrinting.SE!

Really -- get those tiny sample-size tins and test on a random chunk of printed material.   But be aware that stains are intended for wood, and your PLA is 95% not-wood

@CarlWitthoft According to this

@0scar  I stand corrected -- shame on me for not looking at the reel I have at home!

Did you get a chance to test it out yet? Please update.

@T.M. added my answer below.

I ended up using Saman brand water-based wood stain, also from Rona hardware (a brand of Lowe's Canada). The selection of colours for Saman stains was greater than the Varathane stains.
I applied a single coat of colour #117 "Chamois" to the stem portion of the wand, and two coats of colour #120 "Dark Walnut" to the handle. I did not apply a varnish or sealer. The results seem acceptable, given that I Am Not A Carpenter, and this is my first go at printing and finishing wood PLA! Overall, I'm quite happy with the result. I left the PLA mostly unsanded to take advantage of the layers' wood-grain appearance.

Very cool, I didn’t expect it to work that well. Hiding electronics in it is a cool idea too.

Wood stains (as opposed to dyes, paints, etc.) work by having large particles that become lodged in the grain of the wood, yielding a result that varies in intensity with the grain of the wood and thereby brings out its beauty. It's unlikely that they will do what you want, or anything reasonable, on PLA that has wood particles mixed into it. You might be able to find some types of dyes that will work. I've used wood dyes on woods that don't take stain well and have had good results, and if the PLA+wood material consists of a significant amount of wood, it seems plausible that wood dyes might work well on it.

From what I've read: "Composition: 60 % PLA and 40 % wood", please add source for 95 %. I also read that it stains pretty well.

@R -- sorry for misleading you on the percent wood filler

Sorry. I'll edit that in a bit from a real keyboard.

What's with the downvotes? Were they about the mistaken last sentence about composition, based on what Carl wrote? I've edited that out. I feel like the rest of the answer is good/informative - it explains the mechanism of stains and why they're unlikely to work on PLA+wood extrusion the same way they do on actual solid wood.

I did some web research and found several examples that show stains do work on wood pla printed objects. I didn’t answer because I have no experience trying it and the op’s question was about a specific brand of stain.

@T.M.: Now you've got me wondering if you could modulate the flow and extrusion pattern to simulate wood grain and get the stain particles to catch in it like they would in real wood...

@R.. One of the pages I read said they used a trick of varying the nozzle temperature to burn the wood fill to shade the filament slightly differently to simulate wood grain to a small degree. Your idea sounds interesting too but it doesn’t appear necessary to get wood fill pla to take a stain.


text:
How reduce the number of retractions?
I want to print a phone case.
Compared to other models I have sliced, Simplify3D implements a lot of retraction moves.
Is this normal? How can I (Should I?) reduce the number of retractions?
What retraction settings would you recommend in Simplify3D?

Settings

It's unclear what you ask of us, besides try to set the language of your slicer in English if possible, you have a bigger audience that can help you.

Hi Pedro and welcome to SE.3DP. English only on this site I'm afraid, but we do want to help you. Please edit your screen shots, as 0scar states, and your question can/will be reopened. Sorry about that. :-)

Don't worry about the retractions. The number you see seems perfectly fine.

@towe - as you appear to understand the question, do you want to submit an answer (and edit the question to be more understandable)? I could re-open it, so that you can do so, if you so wish

@towe What you pose is exactly the problem, but apparently not using an official version of the tool I can not do certain things.

@PedroMiguelPimientaMorales There are many free software tools you can use, the most popular are Ultimaker Cura and Slic3r. Your edit did not make the question more clear, are you interested in retraction settings for your printer? You don't define that with such a model, retraction settings are calibrated with specific retraction test models.

I have reinstated the images, and edited out the licensing in the image, I've put back in your new question.  I have tried to interpret your English and what you mean. However, it is still not 100% clear what you are trying to describe. Could you check the English grammar and describe more clearly your problem. Thanks :-) What does this mean:  so many points compared with others models? and this: so much point cause the retraction? - I think it is these two statements that are difficult to understand

@Greenonline I think the question should be clearer now, at least as far as I understand it.

@PedroMiguelPimientaMorales I don't think that's the case. Otherwise, it wouldn't need to be cracked.

the last screen shows Retrattion ditance, soßmething about aditional retraction, somethign with vertical retraction and then retraction speed. to answer those settings it would be good to know what filament is used... and the printer model (bowden vs. direct drive).

Enabling combing in the slicer would reduce the amount of retractions of that is what you are after?

@0scarmy 3d printer is Core XY DIY with bowden extruder, HotEnd V6, but i see that you suggestions is try to learn and use cura or slicer, i think the same, better settings and free tools. Thanks for your answer


text:
How to start cycle by using push button
Can any one help me out that how to start a cycle by just using a push button.
Note: Using Marlin firmware, Arduino Mega, Ramps 1.4
I haven't tried altering the Marlin code (as I am new to coding), I was just thinking of adopting this feature as it will be very easy for CNC DIY maker using Marlin code to run a cycle in a loop.

Way more information required. What have you tired so far and what didn't work? Schematic, code? This is way to broad currently.

HI and welcome to SE.3DP btw! :-)

What is a "cycle"? I have no clue what you mean, please explain so we can help you out! Cheers, and welcome!

Yes, @0scar raises a good point, what cycle, or rather a cycle of what? A print cycle, a batch cycle? I seems like you have a good idea in mind, but it's not all that clear or well explained. Please edit and update your answer. Thanks... :-)

@Greenonline, actually in terms of CNC cycle start is very descriptive.

@user77232 - OK, but for the non-CNC initiated crowd, I think a brief explanation might be useful.

Possible duplicate https://3dprinting.stackexchange.com/questions/7713/how-to-make-physical-buttons-send-gcode

Unless you know the structure of the Marlin firmware pretty well, are good at coding (in C/C++), and are familiar with programming microcontrollers, then I wouldn't attempt to do this, IMHO. Adding new features can cause a number of issues elsewhere in the code and need rigourous planning and testing as well as discussion with the Marlin community.
You could however make a request (i.e. raise an issue) to the Marlin community on Github, however, I would seriously suggest posting to the Marlin forum, on RepRap, first, as random suggestions and issues raised on Github aren't really appreciated, without checking on the forum first...
If you really want to get into coding, then I would suggest buying an Arduino Uno and some components and messing about with those first, as well as visiting our excellent Arduino Q&A site on StackExchange as well as the Arduino forums.

Don't go modifying Marlin to do this unless you're using a 32 bit µC.
You're better off controlling Marlin with OctoPrint and writing/finding a module that allows you to kick off a print when a key is pressed on a connected keyboard or pendant.

authors: ปนัตพงษ์ สัตยไพศาล


text:
PLA chemical resistances? Especially HCl, other acids
I'm interested in 3d printed reaction chambers, but can't find any good information on chemical resistances of PLA, just vague claims that it "might not be" "because it's biodegradable" or that it depends on additives (likely true, but it would be nice to know if there's hope of finding PLA without problematic additives if the PLA itself is okay). Is there any published research or even anecdotes (which could suggest it's worth spending effort to investigate further) on this topic?

You could test HCl resistance by squirting out some clorox into a small glass and dip a failed print in. Other acids may be hard to come by using common household chemicals.

actually, this calls for a lab test... I would suggest to design some kind of sample piece (like, a small tray with a diameter 2mm cylindrical cavity, 1.5mm material to the sides, 1mm bottom, 2mm cavity depth, and some 40mm to clamp the sample holder to a bench) and print some dozens of them using identical g-code. mark the sample holders with the concentration and acid used on the holder part. Next is adding one drop of each tested acid to each sample holder and have it sit there for 24 hours.

You could do accelerated testing by putting PLA in hot HCL solution.  It might have a chance with HCL.  It wouldn't have much chance with HNO3 or H2SO4.  Chlorinated plastics are usually stable.  Don't use Clorox, Muriatic acid is HCL.

@LuxClaridge: As Perry noted, Clorox is not HCl. "Muriatic acid" is indeed the easy ordinary-consumer-available source of HCl.

Woops, totally blanked there. It was The Works toilet bowl cleaner that I was what I should have said.

Interesting question. Web research only led to anecdotes that PLA is not terribly resistant to HCL but I couldn't find anything definitive. PLA is a polyester, so data on polyester may give some guidance. https://www.engineeringtoolbox.com/chemical-resistance-polyester-d_784.html This report is on other plastics, but it gives good background on chemical resistance and factors that affect it such as temperature and mechanical stress. https://plasticpipe.org/pdf/tr-19_thermoplastic_pipe_for_transport_of_chemical.pdf

Found another article: http://www.fastenercomponents.com/news/acid-resistant-pla/ That lists the best acid resistant plastics. None that I've searched so far are 3D printable. Also found more material that indicated PLA is likely to be less acid resistant than polyester (usually that means PET if not specified) I think this is one of those cases where 3D printing isn't the right solution. Hot high concentration acid solutions are the worst, and maybe with cooler low concentration you would be fine. If you do some testing, please update.

This might be of use, from Chemistry.SE: How to dissolve PLA (polylactic acid)?. Doesn't mention HCl though, unfortunately, but does mention bio-degradability. TBH, you would be better off asking this question on Chemistry.SE, which is a shame as, if you did, you'd have to delete the question on this site, as you can't x-post.

@Greenonline: Why is cross-posting not acceptable? Last I checked it was fine as long as the question was separately on-topic for both SE sites, but maybe something has changed or this policy is specific to either 3dp or chem SE?

Read Can I cross post my question from one site to another? and in particular Is cross-posting a question on multiple Stack Exchange sites permitted if the question is on-topic for each site? and this answer. So no... would be the answer, 99.9% of the time :-) Do you want me to migrate it?

@Greenonline: If you think it would get more relevant eyes on chem SE, please do. It's not getting any here, anyway.

To be migrated you should, and I quote: This should be fine when limited to acids only, otherwise it might be too broad. It would be good to give it a better title and mention what PLA is, too.

The paper Chemical Compatibility of Fused Filament Fabrication-based 3-D Printed Components with Solutions Commonly Used in Semiconductor Wet Processing, found by user R Kiselev in the comments on another question, has results for this, and finds (this is summarized; details in paper) that PLA has fairly good resistance to HCl at 37%. It did not fare as well against other acids or solvents except IPA.

As @T. M. notes in his comment, there are many good charts of chemical compatibility with various agents.  Very few (I found none) include information about PLA.  By all means, use search engines to find some information.
But, no data source is as true to your specific needs as is testing your candidate materials with your agents.
As a first test put the agent in a tall thin jar or test tube.  Use a few test filaments so that the ends are dipping into the agent.  Check for signs of dissolution, swelling, softening, or any relevant change in the material's characteristics.  Examine the candidate filaments right away, then after minutes, then hours, and if any material survives, perhaps in days.
Print test objects.  Test them with your agent.  Try until you find something that works.
The online material compatibility tables will help you eliminate materials before testing them.  If it says a material is incompatible, it probably is incompatible.  If rated as highly compatible, it should be tested because the formulation of a filament may not match the material tested for the compatibility tables.  If you are running out of options, try the intermediate compatibility plastics.
Bottom line, use the online information to help direct your search, but you should do your own tests.

See this as well:
Chemical Resistance of 3D Printing Filament by Ravi Toor

Summarised chemical resistance per material below (H= High Resistance, VH = Very High Resistance).
Water – PLA (H) PETg (VH), CF-PETg (VH), ASA (VH), ABS (VH), ePLA (H), ONE PET (H)
Acids – PETg (VH), ASA (VH), ABS (H)
Bases– PETg (VH), CF-PETG (VH), ASA (VH)
Alcohols –PETg (H), CF-PETG (VH), ASA (VH), ABS (H)
Hydrocarbons – N/A
Ketones –N/A
Ethers –N/A
Fuels –PETg (H), CF-PETG (H)
Salts – PLA (H), ASA (VH), ABS (VH), ePLA (H)
UV –PLA (H), ASA (VH), ABS (H), ePLA (H)
Oils – PLA (H), PETg (VH), CF-PETg (VH), ASA (H), ePLA (H)

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


text:
Success metrics for 3D prints
I'm doing some testing for objects in 3D printing for a report. I'm trying to get success metrics for it but a bit unsure of what else I could do since would ideally like hard values for it. For example, I have:

Filament needed
Volume
Ease of removal
Weight
Time of print

Would anyone know anything else?

Not entirely sure what you mean by success metrics... could you be a bit more specific? What sort of objects? Do you mean calibration cubes, or any type of object? If the former, then accuracy/tolerance could be useful... i.e. if you are trying to print a 10 mm cube, then how close to 10 mm is the final print, and/or what is the deviation? Maybe expand a little upon your question and what are you trying to achieve, and why... it sounds as if you are a little unsure yourself and are fishing for ideas... Also, are you testing the printer [quality/calibration] or the object [design] itself?

Hi and welcome to SE.3DP BTW! :-)

I would not use any of these metrics for success - the best metric for the success/failure rate I have is complexity and the bed surface / height ratio.

@Trish - Can you help me understand how either one of those metrics helps define "success"? Complexity is a subjective metric (if you can indeed call it a metric). Bed surface-to-height ratio has only to do with the physical dimensions of the printer itself. That would imply a tall printer with a small bed would be more successful than a short printer with a large bed (or visa-versa). Can you help me understand?

as a note: the metrics you look at are all economic. The success of a printed object comes down to factors like the precision of the printer and the amount of time spent on finetuning the slicing profile together with the use of disuse of support (increasing bed surface to height ratio) and the complexity of the print (more complex=less success)

@Pᴀᴜʟsᴛᴇʀ2 Complexity is a relative metric - a rod is low complex, a screw higher, a trapped nut on a capped bolt even higher. it can be also an objective metric - as the number of trigons of a model or the number of direction changes of a g-code. Tall objects indeed fail more often than flat/wide ones - usually due to tipping or breaking/losing some overhung area.

From Trish's chat:

a finished print is a successful one, any print that does not is a failed print. The number of successful prints is antiproportional to the number of distinct outlines and the proportional to the length of said outlines (in other words: low complexity = more sucessful) while a high ratio of the occupied surface compared to the height also is good for the number of successful prints. in other words: if you print a flat pyramid standing on the tip, activate support to get surface. If you print thin parts, print them alone. Tall prints are generally less successful as prone to small errors.

The success metrics are entirely up to you, the user of the printed part. For example, the strength of the part under the load it's desgined for will be critical for an end-use part (such as as hook), but doesn't matter at all for a fit or appearance prototype. Conversely, the dimensional accuracy is very important for a fit model prototyping a complex assembly, but might be unimportant for an appearance prototype or for some kinds of end-use parts.
Because there's a wide range of uses for printed parts, there's a wide range of possible metrics. Mostly they depend on the original design, the print options chosen (e.g. infill style), the material chosen, and the capabilities of the printer. Here are a few:

Dimensional accuracy (of the part compared to the design)
Dimensional stability (does the part warp or shrink afterwards)
Total time to print + finish
Material cost of print (build materials and other consumables)
Weight of printed part
Labour of operating the printer and any post-processing
Surface appearance/smoothness (different for horizontal, vertical, angled, and curved surfaces)
Surface friction
Surface hardness (can you scratch it easily)
Colour accuracy (of the part compared to the design, for colour printing processes)
Colour stability (do they fade over time)
Colour resolution (are colour changes sharp or blurred)
Rigidity (different in different axes)
Failure load (different in different axes)
Non-adhesion across small gaps (as in a tolerance test)
Porosity (e.g. if printing a container for liquids or gases)

A big cross-cutting metric is repeatability. If you make the same print again the next day and repeat any of these measurements, how different a result do you get?
There are also some metrics that are more about the material choice than the way it's printed:

Outgassing
Flammability
Toxicity


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Which nozzle should I buy for Anycubic i3 Mega?
I'd like to buy a new nozzle for my Anycubic i3 Mega because it's not precise enough - it fails to print small details like 1 mm eyebrows.
Currently it has a 0.4 mm nozzle and I'd like to buy a better one but I don't know how to choose one which is compatible with this printer.
If you have any advice, please let me know.

Can you remove your 0.4 nozzle and post a photo of it? I would assume that any similar, compatible, nozzle with the same fitting would do, just use one with a smaller hole. You may need to change some print parameters, i.e. your print speed, but I'm not entirely sure about that.

There are 3 large styles floating around, differentiated mainly from the fitting: M7 with Teflon liner into the nozzle, M6 with a snub nose (e3d-style) and M6 with long body and nozzle ("chinesium")

Anycubic looks like a legitimate manufacturer, with a customer support department.  Call or email them and ask about smaller diameter alternative nozzles.  They may have nozzles to sell you, or they may give you the specs you need to buy a third party compatible nozzle.  With the specs and @Trish's info, you can probably make a compatible choice.

correction of myself:  till today, I encountered 2 Chinesium types that differ from which wrench they belong to (a size 7 or 8): to help differentiating, I put the differentiation into a related question.

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

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

The smaller the diameter, the smaller the filament traces and the higher the print detail resolution. Note that a smaller diameter causes thinner walls for the same amount of (vertical) walls and may require additional perimeters to get similar strength and rigidity. The maximum layer thickness also decreases, as prints with a layer height above 75 % of the nozzle diameter have very poor quality. As an example, a 0.25 mm nozzle should not print layers thicker than $0.75 \times 0.25\text{ mm} = 0.19\text{ mm}$.
As such printing with smaller nozzle diameters increases print time. Also note that a smaller diameter requires more force to push the filament through and could use some extra temperature to make the filament more fluid or reduction of the print speed.
Just buy some spare nozzles of different nozzle diameter and experiment what works best for you.
1) - The other popular style of M6 threaded nozzles has a long body and long taper (often referred to as MK8 nozzle; they come in two different shapes). While these might work, they extend from the heater block considerably further and might need readjustment of the heater block due to their shorter threaded area (as explained here):

sidenote: the nozzle for the e3d v6 and e3d v5 are pretty much unchanged in outer dimensions. IIRC the biggest difference was a better workflow.

Brass will wear out faster and clog more often. They should use a Swiss Micro stainless steel nozzle.

@user77232 that is material dependent. for high abrasive, you even would use an Olson Ruby.

@user77232 Opposed to steel, brass conducts heat way more easily. I have had very few clogs in my brass nozzles, mostly self inflicted by too much temperature due to wrong filament choice in slicer. I've read that steel nozzles are more prone to clogging. I guess it depends on your experience.

I meant that if he's going to be using a .2 nozzle then he should use steel. Decloging the nozzle tends to scratch the hole, which would wear it out faster.

According to a nozzle manufacturer: Regarding Stainless Nozzles; These are not superior in performance to our brass nozzles, and will in fact give you ever so slightly lower printing speeds. These nozzles are exclusively for use with highly specialised materials that may corrode brass nozzles, or for applications where the tiny amount of lead present in the brass nozzles is not acceptable.

We select nozzles depending on what project we want to,do and it must match with the hot end as well.

Hi Donald, and welcome to SE 3D Printing! Whilst your answer may be technically correct, it is rather terse, and, as such, it has been recommended for deletion, unfortunately. If you could expand it then you may get a more positive response. I would recommend that in addition to reading some highly voted answers to gauge the standard expected, that you take a look at the help section relating to answering questions, in particular [answer], and take the [tour] for more information on how stack exchange works. Thanks :-)

Technically any M6 thread will fit in the anycube.


text:
Ultimaker 3 Extended prints pores in walls
We have a fairly new Ultimaker 3 Extended.
When printing ABS with the AA0.8 nozzle and the recommended settings (up-to-date CURA) we receive a very poor wall quality that exposes some kind of pores. I've attached an image of those pores.
I assume those pores are dragged by the nozzle when it moves inwards to print the infill.
I already tried to increase the wall thickness or increase the layer height to 0.3 mm. Are there other settings I might be able to tweak to eliminate those pores?

Welcome to 3dPrinting.SE!

What Z seam option do you use?

While no expert, I'm wondering if you're going the wrong way with tweaking your parameters.
If I'm reading your question correct, you have a fairly large nozzle (it's a 0.8 mm?) and then you're using ABS which requires more heat (230 °C nozzle temp) than say PLA does (typically 190 °C). Along with that you are using a fairly thick print layer of 0.3 mm, where I've normally only used a 0.1 mm layer height. You add all this stuff up and it seems to me the nozzle temps are probably not keeping up with the amount of filament you are trying to extrude, and due to these things, you're seeing the gaps in the print.
My thinking on this to fix your issue is to do a couple of things. You can slow down your print speed to allow the heating element to keep up. Secondly, use a smaller layer height. Both of these things should help, but will increase print times dramatically. You could also go to a smaller print orifice. Lowering the orifice size to 0.4 mm would again, increase print time, but would mean less filament extrusion and the chance for the nozzle temps to keep up with extrusion needs.

At work we print a lot with .8 nozzle in even higher layer heights, that shouldn't be a problem for an Ultimaker 3. I do think you're right about the tweaking part. This looks more like an extrusion start or end problem if the Z seam is random that is.

First of all, I agree with the other answer, which suggests slowing the print and increasing the temperature (upvoted). I also see some evidence of de-lamination between layers in the photo, which lends weight to that idea.
But I want to address this:

I assume those pores are dragged by the nozzle when it moves inwards to print the infill.

Perhaps. There's also a chance these gaps are the result of the nozzle as you suggest...
... however, if that's true, it's almost certainly not the nozzle itself. For the nozzle to cause this problem, the z-axis would actually have to descend as the layer tries to adjust upwards.
Instead, I'd look for a clump of material stuck to the nozzle edge, either during a priming phase in the machine beginning g-code or picked up from the first layer where an early part of a brim/raft/skirt may not have completely stuck to the print bed.
This happens commonly with my printer now that the nozzle has aged some, and I tend to watch the printer carefully while it warms up for a new print so I can remove the priming material with a putty knife before it can cause a problem.


text:
Infill not reaching perimeter
I've got several examples like the image below where the perimeter either doesn't bond to, or doesn't reach the infill. I tried adjusting the infill overlap parameter in Slic3r from its default of 25 % to 30 %, but it doesn't seem to have made a difference. This is on a new Tevo Tornado that's all stock + a Petsfang Bullseye cooler.

Neither speed variations, nor temp variation seems to impact this issue. I'm beginning to suspect that it's related to some sort of play in the Y-axis, as if you look at the defect in the picture, it's the most pronounced running north/south in the picture, which would be layers along the X-axis (meaning their relative position would be impacted by Y-axis movement instability). I'm replacing the leveling springs with PETG standoffs tonight (I have a BLTouch) and will try again then.
I tried 25, 30, and 50 % infill overlap as per a comment request, and that (50 %) seems to have improved another issue where the infill on a first layer would often not reach the perimeter shells.
I tried the following print speeds with all of the following temperatures (nozzle/bed): 190/60 °C, 193/65 °C, 193/70 °C, with 3 perimeters.

That's default behavior. I've also gone to

Perimeters - 80 mm/s
Small perimeters - 20 mm/s
Infill - 90 mm/s
Solid infil - 25 mm/s
Top solid infil - 20 mm/s
Bridges - 70 mm/s
Gap fill - 25 mm/s

With no visible change in this outer perimeter behavior (the faster set of numbers is what I print with in general).

30% should be plenty, but did you try a higher percentage overlap?

@Davo yeah - the default is 25, i tried 30 with no visible diff.

So you did not try anything higher than 30%? Please try 50% - not that I think this is the fix, but I'd like to see what (if any) visible effect it has. You can cancel after a few layers.

please add if you have "print thin walls"

Which material are you printing, considering the temperatures for the hotend I would guess PLA (bed temperature is rther high though).

@0scar PLA is right

This has nothing to do with the infill overlap, the image you've added looks as if the issue is related to non-bonding perimeters (it looks as if it is in between the 2nd and the 3rd perimeter), hence infill overlap doesn't apply here. If that is the case look into this question.
I've had this same issue, the problem is that if the perimeters do not touch, this is most probably caused by insufficient filament flow which can be a result of a too high of a print speed (or too low print temperature) of the inner perimeters. This is frequently seen when printing PETG. PETG has a limited print speed, the PETG I use (premium brand) has a maximum speed value of 50 mm/s, your values are for some values over that value. That would be fine for PLA, but high for PETG, the question is not clear on the material used for this print (the hotend temperatures hint to PLA, the bed temperatures are rather high though).
If it is not related to the material being printed, these gaps are also explained if the positioning of the nozzle is not correct, e.g. caused by loose belts. This is supported by the comment on the first layer:

where the infill on a first layer would often not reach the perimeter shells

I had absolutely the same issue. And after some research I finally found that this is because of wrong pressure advance setting (In case of Marlin - linear advance) in the firmware.
Without pressure advance (linear advance) will be more plastic at the end of the travel rather than at the start. As result the fast full infill will have uneven distribution of the plastic with more plastic close to the perimeters that usually produce rounded corners. The pressure advance makes it better and redistribute plastic flow more even with the speed however if you make this setting too big for your 3d printer and filament then this will result in what you can see on the picture with less plastic at the end of the travel. Basically too big pressure advance parameter will result in less plastic near the perimeters and especially near corners where change in speed happening.

...result in less plastic near the perimeters and especially near corners where change in speed happening The image of the OP shows the exact opposite of what you describe, the image shows filled at corners and free at the wall perimeters.

In the middle of the image where the square part is, clearly visible that perimeters are clearly separated from infill. This is it, the fast infill has less plastic extruded and not touching perimeters. This is not happening everywhere actually because of variations in speed. Also tuning different parameters result in all possible effects but the worst part when weird things happen like infill is good but all perimeters are fully separated even from each other.

Of course, decreasing the speed will also decrease pressure advance effect which is actually introduced for high speed. Actually low speed is a cure for most problems but everybody wants high speed. I also originally solved my problems with lowering speed but good guess and proper tuning of pressure advance parameter made me lucky to print now with good quality and twice less time.

authors: Танюша Томашевська


text:
New use for extruder port
Is there a way to change the use of an extruder port on a 3D printer motherboard to move stepper motors (on y axis) on a 3D printer?
This is for a school project, and we have replaced the extruder with a laser for cutting material.
We were tasked with converting a 3D printer into LOM 3D printer, the laser is set using the fan port, however we still need two stepper motors to move material from one side of the printer to the other after each layer of material is cut.

The mother board we are using is WitBot MKS Gen L V1.0 Controller Board Integrated mainboard Compatible Ramps1.4/Mega2560 R3 with A4988 Motor Driver for 3D.

Welcome to 3DPrinting.SE!

What firmware are you using?

I'm not sure I understand: converting a 3DP to a LASER engraver implies switching the hot-end for the diode driver and the Z axis becomes less valuable. Why are you messing around with the Y axis?!?

If you're doing a laser you can use the fan PWM output to control the laser.

What do you want to use the extra motor for? The answer is yes, if you manage to redesign your slicer and firmware

This is a huge addition that actually explains a lot. As LOM is rare, you should update your question with the additions and how it works and which motor you set up for which. In this case I would put the extruder to control 1 & 8, use X for moving 2, and Y for 4. Z is 7.

If you are planning to use the printer via GCode entirely, then I don't believe it would be too complicated. For example, Marlin treats the extruder as another axis and uses absolute values for it (if absolute mode is on, of course). Since you want to have two steppers, you would have to connect them in either series or parallel (usually the Z motors are wired in parallel on RAMPS type boards, but many people are going for series since it has some benefits, one of them being that the torque will be much more similar between the two motors). Of course lower the stepper driver current to the minimum before connecting, then adjust it to whatever value you need.
I don't think it will work too well if it has to keep the roll tight - in that case, you could be better off by using only one stepper and some kind of force to hold it tight... maybe a small DC motor at low currents?
You can modify your printer firmware and set your own pin assignments for everything, for example in Marlin you have the pins.h file where every pin from the Mega is mapped to different headers and drivers. I don't know if there is any LOM slicer or firmware available, but you could just use GRBL.

With the picture shown, the LOM printer could be almost controlled entirely with a standard printer's hardware and almost no changes to the firmware:

Z controls stay the same, they control 7
X & Y will be used for the laser mirror 4 needs to be controlled by 2 motors to follow 2D Contours. I would not use a swiveling one but a steady laser that targets a 90° mirror mounted so it moves with one of the axis that reflects it to the second 90° mirror that aims it down on the workpiece and is mounted on the second axis. This would be pretty much a Core-XY setup.
Turning the laser on and off can - as said - easily be done with the part cooling fan control
The E0 signal could be used to turn the material feed on both sides, though I  would use only one motor. This stepper should for speed consistency be mounted springloaded and use a roller to transfer movement to the film coil 8, best on an area that is off-limits for the laser to cut in. As a result, I would let 1 spin on itself against some resistance like a spring-loaded bar keeping the film tightened, keeping electronic complexity to a minimum.
Powering the heater can be done via the heater out of the board.
To actually move the heater, I would use the E1 signal on a long axle, pulling the mounting for it from both sides.

This would create a simple order of operations:

T0 # Choose the material Feed
E100 F100 # Pull 100 mm of new material via the roller 8 from 1
Do XY movements with cut
T1 to choose the heater movement
E100 F100
E-100 F100 # Fuse the film with an E1 movement back and forth (or alternate between these two lines to rest the heater on either side, speeding up the process)
GOTO 1


text:
CR-10 Layers not printing after certain amount of filament printed
I am printing on a CR-10 for the first time with white filament1. The problem is it seems that after a certain amount of filament printed one or two layers don't stick to the print which causes a huge gap in the end.
I think the pictures speak for themselves:

Here is what I already tried:

Different print speeds (60 mm/s and 45 mm/s)
Different nozzles (both 0.4 mm)
Print-temperatures of 200 °C and 205 °C
Resliced models in case of faulty .gcode files
Support densities of 10 % to 20 %
Different models

I tried this with two different models, two print attempts each. The gap occurs earlier in the larger model and at almost the exact same layer on both attempts, same for the smaller model.
The most frustrating thing about this is that it happens a few hours into the print so I can't just sit next to it.
It seems that at a certain layer the filament doesn't stick to the print anymore which causes those straight parts.
I ruled out a faulty z-Rod since the gap occurs at different heights.
I am printing White PLA from Janbex with 60 °C bed temperature. I slice with Cura 4.0 (the linux version).

1 I've been printing for over a year now, it's the first time I use white filament. I don't think that it is entangled filament since the spools from Janbex are always perfectly wound. It did occasionally happen with other filament too though but not this often. I have a theory that it might have something to do with the geometry of the model since there were a few very close hard edges at that height. Maybe the filament didn't have enough time to cool down on those spots. I'm trying to print with lower layer height (0.15 now, 0.2 earlier), maybe that will make a difference...

Is it always at the same height or random? You should look into the friction on the spool or for entangled filament.

Testing that now.

entangled filament will make this happens, however this will be more frequently; if not untangled the strength will tighten the spool until stuck the nozzle carrier.

fwiw, i find white filament needs a higher temp than black, maybe it absorbs less heat in the same time? Try cranking the heat 15deg and see if it helps or melts...

If the problem occurs at same height I would focus on the Z axis, in particular the gantry and its rollers.
Try to remove the Z axis screw and feel if the you can slide the gantry up and down with ease, in particular if it gets harder to slide at roughly the height where the problem occurs. You can use the eccentric nuts to adjust the rollers preload and make it slide smooth.
Next on my checklist would be the screw: verify there is no issue on the screw at that height, the Ender 3 is renown for having a Z rod issue due to misalignment between the motor and the nut on the gantry.
While writing another idea came to my mind, but I'm sure already checked that: the filament is not clashing or being clamped somewhere when it reaches that height, right? A filament guide would generally exclude that...


text:
Bed and nozzle temperature jumping
During my last print I noticed this jumpy behavior during heat up (blue is bed, red is hotend):

So I am wondering about the jumps. What could cause this? I do not think that it is a defunct sensor (it is in both sensors) and I also don't think it is real. Could this pose some sort of hazard as temperature might not properly be controlled?
I use an Anet A8 printer with Marlin 1.1.9 and Octoprint

Looking at the graph, it looks like OctoPrint is missing temperature readings from the sensor considering that a) thermal runaway protection is not kicking in, b) the heating curve continues the path it has set in by recovering to the position it should be after failed readings/measurements. You could try to change the USB cable between OctoPrint and printer board.

Since the terminal temperatures never exceed the setpoints, there's no apparent potential for disaster.   Whether it's due to missing readings or to some sequencing of power (current) applied to the bed vs. the hotend, it really doesn't matter.
If you have a similar graph of the temperatures over an hour of printing and you see signifcant anomalies there, that might be of interest.

It looks like everything is ok with the real temperature, and it is just Octoprint missing some readings, like Oscar said.
But I think it is unlikely the USB cables fault, the whole print would fail in that case. I think the PI is to busy, maybe due to a Webcam streaming at high rate (try reducing the framerate). Another reason might be if you use a PI Zero W, especially if you transfer data over the Wifi at the same time, since Wifi and USB cause bottlenecks for each other on that board.
PS. I'd comment, but don't have privilege yet.


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"Seams" in first layer
My first layers started to have these "seams" in them.
I am printing on the  Anycubic Ultrabase.

Any other layer is fine.
Has anyone else experienced similar problems or an idea of how to debug this issue?
The picture is of PLA (BQ Easy Black) printed at 215 °C on the Ultrabase.
The the same issue with BQ Easy PLA red, turquoise and white (205 °C), Zaper PETG Brown 230 °C and HobbyKing translucent ABS Red (245 °C).
Changing the nozzle did not change anything.

Normally, such patterns are caused by too close printing to the bed (nozzle to bed distance too small), but considering the not fully flattened out extrusion lines (on glass I get a mirror shine fully closed surface) this does not seem to be the reason; you could try to increase the gap a little, in Ultimaker Cura this is very easily done with the Z Offset Setting plugin. Add to your question where you print on, it looks as if the bed is not flat.

@0scar Finally came to testing it. you were correct. Leveling the printbed (with 0.25mm cardboard) and the bottom Layer looks like it shoult . Thank You!

I'll make it into a proper answer then! Thanks for the feedback!

Normally, such patterns are caused by too close printing to the bed (nozzle to bed distance too small), but considering the not fully flattened out extrusion lines (on glass I get a mirror shine fully closed surface) this does not seem to be the reason; you could try to increase the gap a little, in Ultimaker Cura this is very easily done with the Z Offset Setting plugin. Alternatively, you could use a little thicker paper to calibrate the bed levelling.


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Strange problem with quality, what might be the reason for these bubbles?
I changed the filament, and to adjust filament temperature, I printed a test model and it looked good:

But printing another part did not go so well:

After the failed print I ran another test:

Еverything is done with the same settings.
And I think the temperature and settings are okay.
Is it possible to have a missed step on the Z axis, and this has caused the crushing of the layers or bad filament quality.
Where does the problem come from?

It looks like over-extrusion. Please tell us the machine, slicer, temps, speed, layer thickness, and material used.

Missing Z steps results in shorter or skew prints, is the cylindrical part with bubbles shorter than it should be? Is the extruder stepper stuttering? Please also add some settings as asked by @Davo. Thanks!

It definitely looks like the temperature is too high
but it can also mean that

the speed is too low and/or
the cooling fan is not driven correctly and/or
over extrusion could play a role here

this is the scenario with all these issues together
too high temperature melts too much filament which is put by too slow movements
;)
check the printing when your object changes from well printed to this ugly state

Looking at the second photograph and the way that the filament switches abruptly from smooth to irregular deposition, I would say that you have a partially clogged nozzle.
Pre-heat the nozzle and extrude some filament. It should drop straight down from the nozzle. If the filament curls as it comes out of the nozzle, the nozzle is partially clogged. You may be able to clear the clog by doing what is called a "cold pull":
Pre-heat the nozzle so that it is possible to extrude filament. Then switch off the heater and allow the temperature to fall below the pre-heat temperature of the filament (140°C for PLA, say). Now disengage the extruder gears and gently withdraw the filament completely from the hot end. On removing the filament completely from the printer, you should find a "bullet" on the end of the filament in the shape of the melt chamber. Hopefully, the dirt that caused the clog will be embedded in the bullet.
In order to prevent dirt from entering the nozzle, it is a good idea to install a filament cleaner. This can be as simple as a piece of sponge containing a couple of drops of light machine oil, or you can make something a little more sophisticated. There are plenty of designs that you can download on Thingiverse.

@Mick Thanks for answer, but i have filament cleaner and i think the nozzle is not clogged.

From third picture - moisture!
Is new filament cheap? I guess it was too long on stash and/or bad package.
Look for Maker's Muse's video on Youtube about this topic.

Moisture has an effect on printing filaments, but not like shown in the image you are referring to.


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Best way to fix ABS corner curling on enclosed Prusa style printer with PEI heatbed?
I'm trying to set up an enclosed (custom enclosure) Prusa i3 style printer for ABS, but having a fair amount of difficulty preventing the part corners from curling.

Detailed specs:

Geetech A10 (generic Prusa clone) w/ PEI heatbed
Custom enclosure
Slic3r software
ABS filament (obviously!)
247 °C hotend temp
115 °C heated bed first layer, 110 °C for others
Fan on for layer 3 and above

Verified heatbed temperature with calibrated IR imager.
Thus far I have been unable to prevent parts from separating from the heatbed during print, primarily at the corners where stress is concentrated.  I've tried various heatbed temperatures from 90 °C to 115 °C, lower hotend temperatures (which just made the problem worse and caused complete print failure), cleaning the PEI surface with alcohol, etc. to no avail.  I'm even seeing this to some extent with Benchy, it shows up as a lift to the stern and bow (slight bend parallel to the keel) -- the print is otherwise basically perfect.
I've attached an image of the more extreme curling -- yes, I should probably be using mouse ears on a part like this, but I see the same thing on parts that shouldn't require mouse ears.
What is the best way to fix this particular problem?  Temperature adjustments, brims, rafts, something else?

I don't believe you should use a fan at all when printing ABS

I tried it both ways.  Didn't see much difference, not sure which one is better in a heated enclosure.  Fan in an unenclosed area would definitely be a very bad idea!

Have you tried using a brim? It looks like you're having an adhesion issue which a brim may account for ... could also be too hot. If a brim doesn't work, I'd try lowering your hot end temp down to 230 °C and bed temps down to 105 °C. 247 °C seems quite a bit too high for ABS.

Normally, 247 ℃ is pretty hot for ABS, the higher the print temperature, the larger the shrink effect. Use brims and an adhesive between print and bed (ABS juice, 3DLAC, Dimafix, etc.).

I haven't tried a brim yet.  I did already try 230 °C, the result was almost no adhesion at all with the part lifting off the bed by the third or fourth layer.  The ABS in question here has a recommended extruder temp range on the spool of 245 °C - 265 °C, it's the Amazon Basics grey ABS.  My extruder max temp is 250 °C so I'm a bit limited in how far I can go in the recommended range.

You have SEVERE issues with retraction.

Adding 20mm mouse ears was sufficient to resolve the problem using the original extrusion / heatbed settings.  I did not expect mouse ears to be required on the Benchy model, but given the lack of better advice it seems this may be a poorly documented "feature" of ABS.
Results on the original worst-case test model:

Note that the brims will not help if the bed is insufficiently leveled -- the brim has to actually merge with / melt into the base part layer, so the extruder height has to be perfect at the brim to part interface.
Example of extruder too far away from bed:

How did you add them?

A tall skirt (like 1 cm tall or more, even as tall as the part) few millimetres from the part would shield the corners and the outer parts from colder air and keep the part temperature high, reducing curling.
It is in principle better than mouse ears, because these just pull the corners, which will still have a lot of internal stress when cooled, but if you keep the part warm as I suggest, the corner will stay flat(ter) by themselves, resulting in a stronger and better print with less internal stresses.


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When installing a glass bed, what do you change?
I have an Anet A8 clone printer with a heated aluminum print bed. I'm considering purchasing a glass bed to add on top of the aluminum. When adding a glass bed on top:

How would I go about installing the glass onto the aluminum bed? Is the major concern here just affixing it?
How do you adjust for the added thickness of the bed in the printer? Is this just through a limit switch adjustment or something firmware/software related?
How much do you adjust your heat (if at all)? Does it take a longer warm-up time due to having to heat the glass?

The most common way to install a glass bed (assuming it's literally a piece of borosilicate glass) is with binder clips. Glass is an insulator, so you may need to adjust your bed temps by a few degrees, and it will take somewhat longer to warm up.
You shouldn't need any firmware changes, but will need to adjust whatever z homing you do. If you have a limit switch currently, you'll need to move it by the thickness of the glass. If you have an inductive probe, it should still continue to work, but your z-offset will need to be adjusted. If you have BLTouch or a piezo, nothing should need to change there.

you might want to adjust the firmware a tiny bit in the heating behavior region though: the expected hysteresis of a bed with a glass sheet is flatter and you should run a PID tune.

@Trish is that the case if you keep measuring temp at the bed heater? I'm surprised that you'd see noticeable performance changes with the addition of something outside of that system..

You can also tape the glass to the aluminium bed using kapton tape if you are concerned about hitting the binder clips.

If you use clips and have exposed traces under your hotbed, cover the clips with insulating tape.

@kolosy by increasing the mass of the heatbed (adding glass), one increases the total thermal capacity. This means, that the heat from the bed distributes onto the larger body: Comparing pre and post mod, the temperature curve of the modded bed is expected to be flatter and taking longer to heat to the same temperature. If you have a very trigger happy Thermal-Runaway-Protection with very narrowly designed heating curve, the slower heating behavior might trip it as it is outside of the expected curve.

@Trish I agree that the system as a whole behaves the way you describe. However, if the thermocouple/thermistor is not moved from its original location, it will likely not see the difference.

I believe that heat loss to the ambient air would be more intense than if there's glass on top.
It shouldn't trigger thermal runaways, but you may want to PID tune anew if you notice any overshoot.


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G-Code for resetting to 100% speed
I had problems printing parts and I figured out that my children have turned the knob of my Prusa i3 MK3 and set the printing speed to 112%.
Since I'm not experimenting much yet, I'm not printing at different speeds than the original speed. I wonder whether there's a G-Code command that I could let Slic3r insert at the beginning of each print to ensure the print starts with 100% speed.

you know that the print speed is swapped to 100% whenever you start the printer, right?

@Trish I thought so also, unless you save it with M500 perhaps? Anyways M220 S100 will put it back to 100 %.

@Trish: yes, if I power the printer off and on. However, I sometimes print several parts in a row.

The RealAnswer(TM) is to lock those kids up and keep them away :-)  -- or Epoxy the knob so it can't be moved...

@CarlWitthoft: sure, I'll explain to them and try to apply some countermeasures. However, this could also have happened to me. On the other hand side I'm happy to see them interested in 3D technology

You can put the speed to 100 % by G-code command: M220 S100.
The M220command is described here.
Know that speed changes sent to the printer have an effect on the next printed layer, it first finishes the current layer at the speed commanded before starting printing the layer.

Works on my Kobra Max, during a 6 day print where my ink swap was missed - THANK YOU

authors: Андрей Васильев


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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.

The model was created using Sketchup

@user15166 sketchup shades faces differently based on their orientation. You can right-click the model and select "orient faces" to see if a square or two will flip, or you can reverse specific faces directly too.

In Sketchup view as x-ray to see and delete internal hidden objects.  On faces delete internal lines where you merged objects to make one face.  Leave only the outline of the faces.


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Sunken and rough bottom layer
Most of my part is printing very well, but I have problems in the bottom layer and in layers that are the first layers, but not necessarily layer 0.
Looking at the print quality troubleshooting, I can't find a problem that fits my needs. Using the terms over there, I would describe it as "gaps in bottom layer".
Photo from part A (RPi case top piece):

Photos from part B (RPi case bottom):
There is a really ugly screwhole (sorry for the blurry picture):

But in the same part, there's an almost perfect much better screwhole:

For the location on the print bed, it's here (both parts):

I have seen the question First bottom layer has gaps, where the OP has already tried a lot.
My thoughts so far:

I don't want to generally lower the Z height, since it prints fine over a large area with a really flat and smooth surface.
I'm not sure I should change the temperature settings. I use the i3 MK3 printer and I use Prusa PLA filament with Slic3r Prusa PLA filament settings.
I don't understand many of the extrusion width / extrusion multiplier options of that question.
I thought I might have had a fingerprint on the print plate. I typically avoid that by wearing gloves and cleaning the print bed with alcohol every fifth print or so. However, I didn't clean before any of the two parts. (I cleaned now)

Given the description and the pictures, can you name the problem and suggest the most likely solution?
Printer and filament details:

Prusa i3 MK3
Prusa PLA filament 1.75 mm, pearl blue
0.20 mm SPEED setting
20% infill
5mm Brim
215°C first layer, 210°C other layers
60°C bed temperature
Prusa PLA default filament settings

I use a Prusa spring steel print bed. No special adhesion, tape or anything. Closest I could find in the shop is smooth PEI, but mine looks more golden.

do you have adhesion issues too?

You print pretty hot, and the gaps between the deposited filament lines give the impression that the nozzle is not close enough to the bed for the first layer. What type of adhesion on the bed are you using? Please update the question.

Agree with @0scar on the heat. Also, even on the "good screw hole" it appears there are irregularities. In the image, at 10 O'Clock of the screw hole, it is rather squished, while directly across at 4 O'Clock (and above it on the longer passes), the extrusion is quite a bit longer and thinner, with some gaps showing. It just doesn't look equal as I'd expect. Maybe I'm out in the weeds and the image doesn't do it justice, so just kinda throwing this out there.

@Pᴀᴜʟsᴛᴇʀ2: that's true. It's flatter and smoother when the lines are shorter, such as in the squished area. It's thinner on long lines. This would mean that I could try to lower the speed of type "solid infill" (pink in Slic3r) like I did for PETG. Maybe I should apply that for all presets.

@0scar: I printed 2 more pieces and yes, maybe I have adhesion issues. I didn't notice it, but the objects go off the steel spring plate a bit too easily. It seems one really needs good senses and a good memory for how the objects stick to the plate. I also changed the filament type. It's the first time I printed with this filament type and color, so maybe I underestimated the importance of things like stickyness.

I know you said you don't want to change the Z height, but it does look like you're printing a bit too far from the plate. I would recommend adjusting your Z-offset if you can, or adjusting the limit switch (or whatever your Z-homing mechanism is)

The variation in print makes an unlevel bed suspect, i.e. wrong Z height in only one area.

@PerryWebbp Indeed, level is the key here, it looks like the bed is not properly levelled or that tape is incorrectly placed.

Add the levelling bed to your answer to be valid :), now is the half of the answer.

Definitely the corner of your bed where print was worse is slightly unleveled (a little too low), because if you look the hole, it has artifacts too, probably because the nozzle was depositing the melted filament from a higher distance than on the "good" part.
You can see later in that hole, that the layers finally catch up with the rest, so:

You need to correct the bed leveling on that corner (too low)

Also, the better part doesn't look right either. You can see the ring around the good hole doesn't close because the filament din't stick at the beginning of the circular movement. Plus, your first layer should be smoother than that, not wormy-like.
To experiment how to get a better first layer you need to tweak in very small amounts:

The first layer height (I may need to be lower for you)
The temperature (I don't think you need more temp for your first layer, probably the fans start blowing after the second layer anyways)
The % of extruded material (you may increase it in very small amounts only for the first layer [and only after a lower layer height didn't worked])
The speed of the first layer (it may need to be lower. imagine your nozzle is trying to print with chewing gum and what would happen if speeds are too high, PLA has a rubbery consistency when melted)

Also:

Be sure the surface is clean

Dust and oils from manipulation on certain spots can cause the filament not to stick, even when you think is clean. I use alcohol when printing on a bare surface, change the masking tape, or use just a paper towel (when I'm using PEI sheet)
If that doesn't give you a a better first layer, but it is at least even, you will need to adjust your z-axis offset or level the entire bed up a little.


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Ender 3 first layer of ESD PLA printing on raft fails
I was asked to print something with ESD PLA and the first layer, on a raft, is coming out like this:

Nozzle temperature was 220 °C and I'm using the default Cura draft profile.
Can you provide any tips on how to get a good print with this?

Can you also add your speed settings?

Do you have the rest of the print specs? Like, when does the fan come on (if at all); what is the extrusion speed; what is the print head speed; what is the bed temp; what is your extrusion multiplier set at;  (anything else which might be pertinent).

The gap between the raft and the first layer is too large (you need to switch to expert mode in Ultimaker Cura to see the values of the option before you can change them) and the hotend is too hot (normal PLA generally prints at 190 °C, ESD PLA prints at higher temperatures; you could aim for 210 °C as a start), This makes it difficult to precisely deposition the first layer on the raft as the nozzle drags the hot filament causing inaccurate first layer deposition.
Furthermore, PLA generally doesn't require a raft to print the part. The Creality Ender 3 has a rough bed (like a BuildTak surface), you could print directly onto the bed surface.
Source states:

Extruder Temp:  Typically 210-220°C.  ESD PLA is a filled product and
  has a higher melt viscosity vs. unfilled PLA.  Therefore, it is
  sometimes necessary to print at higher temperatures than your standard
  PLA to allow the resin to flow properly.

This implies that a hotend of 220 °C mot not be hot enough, in that case the filament is too cold and viscous and gets dragged because the gap is too large.

I'll try your suggestions but I have no issue with regular Pla. This is special electrostatic discharge filament and was wondering if it requires something different. Cheers

PLA is usually 185 to 205C. YMMV

@Huskey27 I've made changes to my answer, you might be printing at a too low temperature. Filament dragging is frequently seen when filament is too hot, but apparently for ESD PLA it can happen when it is too cold to.

Thanks for your tips, all was going well last night so I went to bed while it was printing with a brim to keep it from lifting. Temp was about 220 but then this happened.
The layer lifted right off the body and ended in a mess :/

@Huskey27 That is a new question


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How do I get circles on small interior holes to adhere to the bed?
I’m using a RepRap printer, PLA (Hatchbox 1.75 mm), SketchUp, and Slic3r. The heated bed is covered with a blue polyester sticker.  When I print small holes (1 to 1.5 mm radius), slicer software considers the holes outside edges for the first layer and prints them before the internal first layer. The problem is, unlike the actual outer edges, the holes have no brim and the small first layer circles stick to the extruder rather than the bed. The rest of the first layer print sticks and the print eventually recovers with slight defects depending on where the lifted circles end up. If I could print the first layer circles after the surrounding first layer was printed, this wouldn’t be an issue.  I’ve tried different bed and extrusion temperatures.  All four holes in different locations do the same.  First layer is 0.3 mm thick.  Second layer is 0.2 mm thick.

Could you add an image of the print and of the sliced first layer?

I don't have a picture right now.

I'm considering making the first layer solid across the holes, then punching through the single layer.

I had a similar issue and I had trying masking tape or glue to try and help and they didn't make a difference. I then tried a 3D print build surface. This has helped and I no longer have the issue. Have a search and see if you can find one which will fit your current build plate.

try to print the first layer 0.2mm

Putting a 0.2 mm layer across the hole bottoms so that the slice didn’t put small circles on the first layer worked.  Large circles on the first layer weren’t an issue.  This worked because they were through holes that could be located from the top and they were holes for screws that could easily penetrate the thin layer.  The layer was too thin to keep the screws from turning and feeding into the attached part, but served to keep the screws from falling out of the hole.  It would be difficult to locate holes that weren’t through holes using this method.

@PerryWebb I've done so many times (because this gives a better aesthetic first layer), to find those holes look at the design and push with you fingers over the surface where a hole should be, the 0.2 mm layer will dent, while the rest won't.

are you using hairspray or tape to help with bed adhesion? If not that might help.
Also try printing the first layer slower or try adjusting the bed level offset so you are squishing the first layer down a bit more.

The z offset is close enough that the extruder slightly marks printed surfaces if moving across them.

how much the first layer measure? if your first layer should be 0.3mm and this measures 0.38 so your Z offset is incorrect. and this parameter is not enough to adhere the filament with a nozzle 0.4

I would use a very slow print speed for the first layer, something like 20mm/s or less.
This will make your first layer so slow you will be tempted to bite the steel rods.
If you were using Cura (I don’t know if Slic3r has a similar feature) you can change this parameter only for those areas where you have these small holes: with the Custom Supports plugin you can specify a different print speed for a specific area

You didn't say what type of bed you have, but I'm guessing glass. Do you have a BuildTak or comparable generic surface you could clip on and use? I've never had adhesion problems like this with my Ender 3, which came with a BuildTak clone; PLA just sticks, with no brim, no glue, no hairspray, etc.

There is a tape sheet over the glass.

@PerryWebb Maybe you should add that to your question by [edit]. What kind of tape? Painters tape or Kapton tape? I use 3DLAC on glass, never fails.

Given how little trouble I've ever had with adhesion compared to how much folks seem to have with tape, glue, hairspray, etc. on glass, I think there's got to be a huge difference in the effectiveness of BuildTak/clones vs these methods...

Print at 5% of the print speed, and ramp up cooling to 100%. This should give the plastic time to shrink and adhere to the bed. If not then use a raft.


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How does acetone "rejuvenate" PEI?
The Prusa3d knowledge base mentions that acetone will "rejuvenate" PEI in addition to cleaning oil and grease from the surface.

About once a week, or when prints stop sticking, use ACETONE to clean the bed. It removes grease better than IPA or Windex. It also rejuvenates the print surface. However, if you use acetone every day, PEI will become brittle and start cracking.

From a chemical or physical perspective, how does acetone affect the PEI surface?

Looks like marketingspeak.  A cleaned surface should behave like a new surface, assuming the PEI is homogeneous material.

Thanks!  I can verify that it's customersupportspeak, as that's what they advised me when I contacted them.  Interestingly enough, it worked very well and restored my print surface to like-new condition.  I don't know if their PEI surface is homogenous, although they don't say anything to the contrary.

Rejuvenate is probably a bit of an exaggerated term. The number one adhesion suppressor is grease. The stuff that comes off of the fingers used to handle the sheet. Even if you are careful and only handle the sides, the grease will be carried to the center of the plate next time its cleaned with less aggressive solvents.
Isopropyl alchohol does break down grease but not to the extent that acetone does. Acetone also attacks plastic particles that accumulate on the print surface over time.
PEI is resistant to a wide array of chemicals[1] including acetone but it can become brittle if exposed to it too much especially when hot so acetone is not recommended for daily cleaning.
[1] Ultem Product Broshure table 4-3

Excellent reference. Your last point is the one I'm trying to understand in more detail.  What physical or chemical change takes place that makes the PEI brittle?  This is more for intellectual knowledge than for practical considerations, of course.

@mark-harrison unfortunately GE does not specify what happens to polyethermide when it's attacked by ketones, they only list the failure mode after immersion which is rupture. My wild guess is that this is due to loss of molecular mass. PEI molecule does contain a methyl group (CH3) so acetone may be able to eventually break that away from the molecule.I'm not a chemist though and I am really grasping at straws here. This is probably a question for chemistry.stackexchange.com

TIL, there's a chemistry stack exchange!

Acetone is smelly nasty stuff.  Here's a sample recommendation for PEI maintenance from one of a few (million?) 3d printing help sites.

Use isopropyl alcohol, methyl alcohol, soap, Heptane, Hexane, or
  Naphtha. Avoid ketones (such as MEK) or strong bases (such as sodium
  hydroxide).

Maybe it's just me but in my experience Naphta smells even worse than acetone and doesn't evaporate as quickly so the smell lingers around longer.

@anttix naphta is a complex mix of aromates, which is why it smells. it is also a super good solvent for most fats, like grease or fingerprints.It is, as an aromate, at least possibly cancer inducing (actual classification depends on the exact mix)


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Layer lifted and separated from ESD PLA
I'm using the default Ultimaker Cura draft profile but with the nozzle temp at 220 °C because this is a special ESD filament.
All was going well after some troubleshooting thanks to some users on 3DPrinting.SE but this happened over night:
What would cause an entire layer to lift off the main body, continue to print and then turn to spaghetti?
The red circled part was supposed to be part of the blue outline.

Please take pictures while is is still on the bed next time, it is really hard to make something of it now. Do you mean that the back part should have been on the top part?

This is what I call a wayward print! ;-)

I was running late for work and was supposed to bring this into a friend so I just removed it and took pictures. I updated the post with what was supposed to happen.
The part that got lifted had several good layers on it.

Barring a mechanical issue where the bed dropped all of a sudden, I would suspect a clog. The filament got stuck, the printer continued printing air for a few layers and then the clog somehow resolved itself. Maybe the layer geometry changed forcing more material through which created enough pressure to break it free, maybe ramming with retractions dislodged it, who knows.
Of-course it may also be a simple mistake of attempting to print something that hangs in mid-air without supports.

The spool kept getting caught on itself and tightening. I unrolled some of it and rewound it and the print came out perfect. @anttix was almost correct with the clog theory.

Thanks for sharing your solution! Filament entanglement is always something to look out for.