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Expansion in bottom skin after first layer
I'm having an issue where prints with narrow tolerance come out fused. This makes it pretty much impossible to print anything with narrow parts. It seems to be mostly (maybe only) an issue in the bottom skin layers. Once it gets through those, the rest of the print goes smoothly and tight tolerances are not a problem.
Here's an example where I've tried to print some hinges:

It's a test print where each hinge has a different tolerance, so the left and right are expected to look different. Below each real image is a preview layer from Cura showing how it's supposed to look.
The first layer appears OK. The second layer looks a little messy, and the gap between inner and outer circles has shrunk. By the third layer the hinge on the right is completely fused.
The printer is an Ender 3 Pro with a glass bed (flat glass, no special surface), BLTouch, and Marlin 1.1.9. The slicer is Cura 4.6.1, and for this test print I used the default for "Super Quality - 0.12 mm" at 200 °C and 60 °C bed with no changes. The filament is Mika3D PLA.
Some things I've tried to fix this:

Calibrated e-steps (currently set at 95.88) - no noticeable difference
Calibrated flow rate (got 97.859 % but returned to 100 % for this test) - no noticeable difference
Varying temperatures from 190 to 230 °C by 5 °C increments - no improvement from 200 °C
Set "Initial Layer Horizontal Expansion" to -0.1 mm, -0.4 mm, and -1.0 mm in Cura. - no improvement.
Set "Initial Layer Flow" to 90 %. - no improvement.
Obsessively leveled and re-leveled the bed. - no improvement.
Moved the Z-offset up and down to get more or less squish on the first layer - no improvement.
Tried various brands and colors of PLA - problem is consistent.
Reduced build plate temperature to 45 °C after initial layer - no improvement.

What else is there to check?
Edit 2020-06-26:
At R.. GitHub STOP HELPING ICE's suggestion I returned the e-steps to default (93), re-leveled the bed, and adjusted the z-offset tighter. I made 10 attempts with varying z-offsets, and here's the best one:

The first layer looks better! But the second and third layers are just as bad as before, in fact maybe worse. The circle on the right completely fused on only the second layer. And the top surface is just as ripple-ey and messed up as before.
Here's a closeup of the fourth layer to show how bad it is:

So although the re-calibrated e-steps may have been a problem, that clearly wasn't the only problem. What else should I be looking at here?
Edit 2020-06-27:
At Davo's suggestion I double-checked all my slicer settings. Flow is set to 100% everywhere, wall thickness is 0.8 mm for two walls (so 0.4 mm each), and nozzle diameter is correct at 0.4 mm.
At R.. GitHub STOP HELPING ICEs suggestion I double-checked my filament diameter. It is set to 1.75 mm. On the actual filament, my digital caliper measures 1.74 to 1.76, within the expected tolerance. So that doesn't appear to be the issue.
At 0scar♦s suggestion I tried a print with 0.2 mm layer height. Here's the first layer:

Looks like the same over-extrusion.
Then I tried reducing the flow multiplier to 90% (for both "flow" and "initial layer flow") and printing at 0.2 mm layer height:

Better, but it still looks over-extruded!
I don't know what else to try.

Strange, usually it start bigger and then reduces. At what layer does the part cooling fan kick in? Also is 0.12 mm a native step for your printer? Most lead screws have a 2 mm pitch leading to a 0.04 mm full step. If yours is different you might be missing//skipping (micro) steps.

@0scar As far as I can tell, 0.12 mm (and 0.16, 0.2 etc) is native for the Ender 3. The fan is off for the bottom layer and is set in Cura to hit 100% at layer 4. Cura says it "gradually increases" in between. Would turning the fan to 100% at layer 2 help?

Esteps for Ender 3 is 93. Of course if you increased it you're overextruding and too much material to fit in the space means some will expand to the side.

It looks like your first layer avoided the problem by the bed being way too low, compensating for the overextrusion with extra height. After that the error quickly builds up since each additional layer is only the nominal height.

BTW +1 for nice clear pictures of the problem.

If you look at the close-up photo you see that a) you are still over-extruding, or b) the Z-axis doesn't advance enough. Try to print this with 0.2 mm layer height, although 0.12 mm being a native layer height it doesn't seem to work for you.

@0scar I tried it with 0.2 mm layer height. Still looks like it's over-extruding. I tried reducing the flow multiplier in Cura to 90%. It's better, but still over-extruding. See photos added to the question. What could be causing this?

Do you have a caliper to measure the diameter of the filament at various positions?

@0scar Yes, my digital caliper reads 1.74 mm to 1.76 mm everywhere I check. My printer profile is set to 1.75 mm, so I don't think that's the issue.

I think this is resolved. After looking at every conceivable source of over-extrusion and coming up negative, R.. GitHub STOP HELPING ICE suggested that it might be a mechanical problem in Z axis movement, like in this question.
I checked by leveling the bed and zeroing the Z axis at 0.05 mm above the bed, using a feeler gauge. I gave it the instruction to move the Z axis up by 0.2 mm (to simulate a single layer), then checked it with a 0.25 mm feeler gauge. It did not fit. I raised it .01 mm at a time, and I was not able to insert the gauge until it hit 0.5 mm!
I printed a 20 mm test cube and measured the Z height:

At 19.58 mm, it was short. Only a little bit though, which is consistent with Z problems only occurring in the first few layers for some reason.
Based on the advice in the other question, I fiddled with the eccentric nuts on the left and right side of X axis gantry, adjusting them to be tight enough that turning the wheels moves the gantry up and down, but loose enough that I can still turn the wheels if I hold the gantry in place.
I checked again with the feeler gauge, and this time the 0.25 mm gauge fit just fine at 0.2 mm. Cool! I printed another test cube and measured:

OK, at 20.06 mm it's not perfect, but it's a lot better. I printed the hinges again:

Again not perfect, but so much better. And the specific problem of uncontrollable expansion in the 2nd and 3rd layers is totally gone.

OK, let's start with your pictures. Putting aside the expansion in the XY plane, layer 1 looks seriously underextruded (gaps between the lines, even) while layers 2 and 3 look severely overextruded. It would be possible to achieve this with a reduced first-layer flow setting, but you haven't indicated that, and moreover, in addition to looking underextruded, the first layer's lines don't look very flat - they look a lot thicker than 0.12 mm. I suspect if you can take a caliper with resolution greater than 0.1 mm and measure the thickness of the first layer, you'll find it's at least 0.2 mm thick, maybe more.
So, what's happening? You're overextruding by a lot, but have lowered your bed enough to (more than) compensate, giving the excess material in the first layer a whole 0.2 mm or more of vertical space to expand into, preventing it from being pressed against the bed and taking up the horizontal space it should. Now, as soon as you start the next layer, the big problems start. Since the nozzle has only moved up by 0.12 mm, you only have 0.12 mm of vertical space, and the overextruded material gets squeezed out horizontally. Some of it goes down into the gaps between the lines of the first layer. But by the time you get to layer 3, there are no gaps and things go really bad.
What's the source of the overextrusion? Your "esteps calibration". This is not a number you need to calibrate. It's a function of the extruder gear, and for the Ender 3's (including the Pro's) factory gear it's 93.0 (*).
After you fix the overextrusion by putting esteps back to the right value, you're going to need to re-level your bed. If you use the paper method, make sure there is significant tension on the paper and it does not slide freely under the nozzle at Z=0. If prefer using real metal feeler gauges and moving the nozzle to Z=0.1 to level. (You mentioned that you have BLtouch, which I'm not familiar with, but as I understand it you still need to calibrate it due to possible difference in sensor height and nozzle tip height.)

(*) Note that for compressible filaments like TPU and to a lesser extent PETG, compression of the filament in the gear will alter the effective steps per mm of (uncompressed) filament moved. However, rather than modifying your firmware esteps setting for this, it makes a lot more sense to model that as either a flow adjustment percentage or a narrower filament diameter (since essentially that's what it is -- the filament becomes narrower at the point of measurement), since slicing software supports adjustment of these per-material. So, don't touch esteps unless you replaced extruder hardware.

Everything you say makes sense, and I'll try reseting e-steps to 93, re-leveling, etc. But in the meantime there's one thing I don't understand: when I calibrated e-steps by disconnecting the Bowden tube and telling the extruder to run 100 mm of filament, I got 97 mm. After setting e-steps to the calibrated value (95.88) I did it again and got exactly 100 mm. You're saying e-steps shouldn't be changed for stock hardware, but it doesn't appear to be extruding the expected length with the default value. So what am I missing here?

I followed your suggestion, returning e-steps to 93 and raising the bed. The result is better (not perfect) on the first layer, but just as bad on subsequent layers. So although that may have been a problem, it clearly wasn't the only problem. I added photos of the results to the question. What do you think?

Check parameters related to flow - extrusion multiplier, extrusion width, nozzle diameter, etc. You are clearly (for some reason) over-extruding.

It's still badly overextruded. If you don't have an extrusion multiplier/flow % in your slicer settings, perhaps your filament diameter setting is wrong or your filament is actually of the wrong diameter?

@Davo I double-checked my settings. I think the extrusion multiplier is what Cura calls "flow" and it's 100%. I'm guessing extrusion width is Cura's "wall thickness", which is 0.4mm. My nozzle diameter is 0.4mm and that is set correctly too. I dialed flow down to 90% and still got over-extrusion. See photos added to question. What else could cause this over-extrusion?

@R..GitHubSTOPHELPINGICE I double-checked the setting for filament diameter, and I measured my filament just to be sure. It's set 1.75 mm, and the actual filament is within 0.01 mm of that. My extrusion multiplier (Cura calls it "flow") was set to 100%. I tried reducing it to 90% and it's better, but still over-extruding. See photos added to question. What else should I be looking at?

Perhaps you have a mechanical problem in Z axis movement, like this: https://3dprinting.stackexchange.com/q/8022/11157

@R..GitHubSTOPHELPINGICE That looks like it! I homed the hotend then moved it down until my 0.05 mm feeler gauge just fit under it, and zeroed it. Then I moved Z up by 0.2 mm to simulate a layer and tried the 0.25 mm feeler gauge. It wouldn't fit. I had to move Z all the way up to 0.5 mm before I could get the 0.25 mm gauge in. So there's definitely an issue with my Z axis movement. Thank you for help figuring this out.

@Robert: Your self-answer is very good and I think it should be the accepted one. Thanks for the offer though.

There is a problem with Z-axis' uneven movement. I worked a lot on fixing this and the solution I came up with was to reduce flow in Cura post-processing. You need to measure the movement of the X-axis in the vertical direction on the first layers and calibrate flow. Hope this helps as it helped me.

I had the same problem with my Ender-3 V2.
You need to check if the feeder bracket is square like explained in this YouTube
If that is not the problem maybe you need a custom bracket to change the spacing between the Z-motor and the frame like this, this or this
I have improved mine a lot using:

This Z-motor mount
Using glue stick instead of squeezing the first layer
Leveling the bed using a feeler gauge instead of a piece of paper
Initial fan speed 100 %, all layers the same
Same flow rate, line width, line height on all layers
Build plate 40 °C, nozzle 205 °C
Seam Corner Preference: Hide or Expose Seam


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How to remove a stripped nozzle
A few months ago I got an Ender 5 printer. After a few successful prints with only PLA, I started getting a lot of issues. The last time I came back after an hour and there was just a bird's nest around the nozzle.
I cleaned up all the PLA I could visibly see around the nozzle and the inside as much as I can tell. I decided to replace the nozzle, but when I tried to remove it, it was stuck.  All the wrenches I have couldn't hold it, and now it's stripped pretty smooth.
What options are left? Was there PLA stuck inside the hot bed that's holding the nozzle?  I heated it to printing levels to soften it but no luck.

Pics? You probably need to replace the block but it's not expensive or a big undertaking.

Try a pair of vise grip pliers, that should work. But as suggested, replace heater block and nozzle, see this answer.

source: Stack Exchange

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

sort: votes


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PID autotune fails with a temp too high
Working on upgrading my Ender 3 to a dual extruder setup using the Winsinn dual hot end and MKS Base V1.6 motherboard using Marlin FW 2.0.5 and am unable to get the PID autotune to work. When I start the autotune, the temperature spikes pretty quickly and quickly fails, either heating to 60 °C or 200 °C (M303 C5 E0 S60) for either hot end (E0 or E1). After looking through other online messages, I used 24 V heater cartridges rather than the 12 V ones that came with the hot end. Aditionally, I have the thermisistor settings to use config 6 (rather than 1) after reading through user recommendations on the hot end. After failing to get the hotend to heat properly, I have the following questions:

Should I try reducing the current to the cartridge? Currently set to default of 255?
Are there any other PID changes I should make to allow the autotune to figure out the right parameters to use?
Are there any other tests recommended to figure out why the hot end heats without being stopped by Marlin?

Here is a chart showing the temperatures of the hotends and bed while running autotune on T0 and T1. Weird gap in second attempt was verifying that the right sensor was plugged into the right mainboard pin (no power going to hot end at this time).

Thermistor settings:
#define TEMP_SENSOR_0 6
#define TEMP_SENSOR_1 6

Have you looked into this question?

Are you sure the temperature readings are correct? If I read the graph the hotend is heating up 200 °C in about 30 seconds. This seems unreasonably fast (just based on the heat capacity of a standard E3D heater block this would require at least 64 W). You write that you used a 24 V heater in place of a 12 V one. Doing this should drastically decrease the heater power. Did you make a mistake when writing the post, and actually used a 12 V heater in place of a 24 V one? If so, that might explain a lot. In this case, you should immediately revert to the appropriate heater cartridges for safety.

Good catch, the heating up is so fast that the #define PID_FUNCTIONAL_RANGE 10 is too little for the amount of heat pumped into the heater block causing a large overshoot causing the PID tuning to stop. Maybe you can measure the resistance of all 4 heater cartridges?

@Tom: OP has an aftermarket hotend that came with 12 V cartridge, but power supply is 24 V so the replacement should be correct.

@R..GitHubSTOPHELPINGICE Not if the wrong heaters are delivered or the wrong ones inserted :)

@0scar I can check the resistance of the heater cartridges to make sure that they are 24 V (would be a bummer if they were in fact 12 V but would explain a lot).

@0scar do you have any reliable references for testing the resistance of the cartridges? I have looked around and not finding a good video that shows how to do that. Not too experienced with electrical stuff, and am not wanting to short my printer out, cause a fire, or electrocute myself.

I use a multitester/multimeter for that. You can calculate the resistance roughly, voltage squared devided by power in watts, your reading should be close to that value. About 4 Ohms for a 12 V and about 14 Ohms for 24 V cartridges.

I tested the resistance on the factory hot end for the Ender3 and saw 14 Ohms of resistance (same reading as you said I should expect for 24 then checked the 12v ones supplied with the hot end and the measured 4 Ohms, unfortunately the cartridges I have measure 4 Ohms just like the 12v cartridges do. I left a review on the product in Amazon, and have a better rated set on the way (should arrive Sunday). I updated the post to reflect the product that was in my order.

As the heating curve is very steep, it could be that the wrong cartridges are inserted, or you have been supplied the incorrect cartridges. (Not long ago I've had a similar experience with a 12 V cartridge in between my 24 V spares...)
To find out for which voltage the cartridge has to be used you can measure the resistance with a multitester/multimeter. You can calculate the resistance roughly by using the formulas:
$$ U = I \times R$$
$$ P = {U}\times{I} $$
Combing these formulas gives:
$$ R = \frac{U^2}{P}$$
(P is power in Watt [W], I is current [A], U is voltage [V] and R is the resistance in Ohm [Ω])
Your multimeter readings should be close to the calculated values. About 4 Ohms for a 12 V/40 W cartridge and about 14 Ohms for a 24 V/40 W cartridge.
Since the Ender 3 is running on 24 V, you need the higher resistance cartridges.

If you are using a 4 Ω (12 V/40 W) cartridge on 24 V, the power would become:
$$ P = \frac{U^2}{R}= \frac{24^2}{4}=144\ {W} $$
This amount of power will quickly raise the temperature of the nozzle! It then becomes very difficult for the PID control schedule to harness that power (e.g. overshoot control).
From the question is read that:

I used 24 V heater cartridges rather than the 12 V ones that came with the hot end

If the cartridges are truly 24 V this rapid heat-up is not expected, it could be that you accidentally received incorrect cartridges, you should measure the resistance to be sure.

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


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OctoPrint won't stop my print with a pause
Using the PrusaSlicer I discovered that we are able to insert a pause in mid print.
I wanted to use such feature to insert a lens in my print so I don't have to glue 2 parts to make my magnifying glass.
But unfortunately the print didn't stop at the specified layer.
Trying to manually pause the printer from the LCD didn't worked either.
The only way to stop my print is to print from the SD card instead of using OctoPrint.
Is there a pre-requisite to be able to trigger a pause from the G-code using OctoPrint?
Apparently PrusaSlicer insert an M601 command, maybe this had to be somewhat changed to another G-code command?
My 3D printer is an Ender 3 with an alternative 32-bit board : BIGTREETECH-SKR-mini-E3 V1.2
I'm using the stock firmware : firmware-bltouch-for-z-homing.bin
I tried to look into the Configuration.h to see if there was a pause feature to enable but I didn't see it.
I've tried to pause, it didn't even trigger automatically when printing from the SD card... Maybe I need to tell the slicer to issue another G-code that is not M601...

Are you able to edit in codes like M4, G25, or M226? Are you able to insert a very slow move to home at the end of the layer, giving you time to place your lens?

I don't manually edit the code, I was hopping to set the slicer in such way so I don't have to hack into the file.
I'm not familiar with M4 nor M226, I'll give them a try

@Davo You probably mean G4 not M4 and M25 and not G25 ;-) Note that M25 should work for pausing SD prints. A safe way to pause a print is to insert a dwell time with G4.

Pausing has been asked before, there are multiple solutions posted. Note that it also depends on the version and configuration of the firmware.

I've tried to "insert custom GCODE" M25 in the slicer, the print paused nicely, the LCD showed me "print paused" message and I could then place my part to be embedded into my print, but then impossible to resume the print. I've waisted enough PLA today, I'll glue the parts with super glue... I think pausing prints aren't compatible with OctoPrint / my board / my printer or whatever. Thanks you all for helping me

@Sandra Clicking the/a button on the display didn't resume it?

Sadly no, I selected "resume print" from the LCD and the printer stay paused.

I think you are running Marlin Frimware 1.1.x, this means that you could use M600.

If you want to pause at the Octoprint command streaming level rather than at the printer level, have your slicer emit the Octoprint @pause command rather than real gcode for pause. This will cause it to go into the paused state and not send any further commands until you hit resume.

Docs link https://docs.octoprint.org/en/master/features/atcommands.html
Supported from octoprint version 1.3.7

authors: Марина Степанова


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Paper as build surface - how will that work?
I have a Creality Ender 3 that needs a build surface (both the build-tak sticker and the removable stiff backer). My dad has been pestering me to try using paper as a disposable surface. I am hesitant to do so for concerns regarding fires and degrading the bottom of the print. Has anyone here tried this and what were the results?

Blue masking tape is a common bed surface, especially for unheated beds. It is effectively an adhesive applied to a paper, although I suspect the paper is treated in some manner to serve as a barrier to paint, as the blue tape is sold as paint masking tape.
A sheet of ordinary paper isn't likely to catch fire, as the bed temperature will not reach combustion temperature for paper (more than 230 °C), but you still have to have the means of providing adhesion of the paper to the bed.
A thick enough weight of paper may provide sufficient rigidity to provide for a stable print surface, if the perimeter is well secured and uniformly (smoothly) attached.
You'll have to experiment with various types of paper surfaces as well, as some may be treated (calendared) during manufacturing, which could affect the results.
Blue tape is your best bet if you want disposable. Also if you use care in removal, it is not a single use bed covering.

Paper could be clamped down at the sides if you want to avoid glue. Not just at the corners, it would need to be clamped down on all sides to make sure it doesn't crinkle


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All-metal hotends are less forgiving / not as good for PLA -- but how bad?
Currently, I'm using a Creality printer to print PLA (that's what I have on hand) but I'm definitely interested in working with other materials that require higher temperatures (both much higher, and just enough higher that the stock hotend is very marginal) in the future.
I understand that all-metal hotends are less forgiving and that they particularly are not the best for printing PLA, and shouldn't be assumed to be an upgrade when only printing PLA.
What I don't understand is, how bad are they? Are they so bad that I should plan on changing back to a PTFE hotend whenever I print PLA or ABS? Or are they suitable for use on a printer that is sometimes used for printing PLA and ABS and sometimes printing high-temp filaments?

Simplified version (needs expansion to be an answer): due to heat creep & lacking non-stick property of PTFE for the entire path to nozzle, retracted filament can finish solidifying and jam in heatbreak/coldend.

ABS does not suffer from heatcreep to a degree that you need to concern about it like for PLA.

From close experience, I know of printer types (commercial available, I will not release the brand) that are excellent in printing ABS, but cannot produce a single print in PLA no matter the settings! Answering how bad is subjective, I'm running an Ultimaker 3 (no PTFE lining) a large CoreXY (no PTFE lining) and my own Prusa i3 design (with lining), either genuine E3D and clones, and can print PLA without a problem. So it ranges from total success to total failure. IMHO, your question cannot be answered. Cooling of cold end and tuning retraction settings is key.

All-metal hotends are less forgiving

Yes

not as good for PLA

No

but how bad?

That is very subjective and totally depending on the skill of the 3D printer operator! So, that part of the question cannot be answered.
Fact is that all-metal hotends are sold as being upgrades to lined versions, this is simply not true. It is a different design that can handle higher temperatures. To operate such hotends you require a little more experience as these hotends are a little less forgiving if you do not have the right slicer settings. Key parameters are hotend temperature, cold end cooling and retraction speed and length and amount of retractions in the model.
Another fact is that e.g. the Ultimaker cores concept (we opened a 0.4 mm core to see that for ourselves) doesn't use a PTFE lining, nor do other brands. They can perfectly print PLA (even with a high retraction length). The only time if failed printing PETG (higher temp than PLA) was the result of a heat creep induced clog which was caused by a cooling fan failure (the cooling fan ingested something and seized up), so just one print of a few meters of the several kilometers 2.85 mm that got printed.

Are they so bad I should plan on changing back to a PTFE hot end?

No, all metal hot end are not that bad, and may even be beneficial when printing at higher temperatures. You mentioned that you want to print ABS and other such materials. At temperatures this high, my understanding is that the PTFE tube in the hot end may melt, or at least become so damaged that the hot end is blocked, leading to needing to replace the tube. My first 3D printer used a PTFE ho tend, which due to the printing temperatures I was using, and lack of knowledge of the many types of hot end, the tube got damaged after about 2/5 hours, leading to me needing to replace the tube. I eventually sent the printer back, got my money back and got a printer with an all metal hot end. That has never failed me in hundreds of hours of printing.

Are not the best for printing PLA

I have never had a problem printing PLA with an all metal hot end, however if you are printing just PLA, a PTFE hot end would be just fine, although not as versatile if you wanted to try different materials in the future.
In Summary:
Provided you print fast enough (I regularly print at 60 mm/s) to ensure that no filament cools down in the hot end you should be fine.

Could you expand on whether this includes printing of models with lots of travel moves where you need frequent retraction to print accurately (without oozing loads of material all over the place in the wrong places), with a working amount of retraction? It's very plausible for an all-metal hotend to work fine printing vases or anything with simply-connected cross-sections, but jam badly due to heat creep under repeated retraction. And as I understand it the particular hotend and how it's installed make a lot of difference to whether that happens.

@R..GitHubSTOPHELPINGICE Retraction typically doesn't cause me any issues. Provided you aren't retracting for hours (unsure how that is even possible), you should be fine. The hot end is still warm enough to re-melt the filament. I always just push a bit of filament through before I start my first print, just to ensure that it is all melted. also, I print 5 - 10 degrees warmer with an all metal hot end just to make sure.

Concern is not duration of a single retraction but retracting roughly the same segment of filament many times, and having it get stuck because of how/where it melts/solidifies or because of non-smooth (compared to PTFE) metal surface or actual ridges.

@R..GitHubSTOPHELPINGICE Sorry, I misunderstood. Surely if the hot-end wasn't smooth, or was so rough it was causing major issues, it would be time to get a new one?


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What hotend designs exist as paired all-metal and PTFE-lined versions?
I know that the E3D V6 hotend exists in both the all-metal V6 version, and the PTFE-lined Lite6 version with the same mount and form factor.
What other hotend designs are available like this?

Hotend Designes in General
Lined
Makerbot Mk8 & e3D Lite6
The Makerbot Mk8 seen on many Chinese machines and the E3D Lite6 are both lined hotends, which means the PTFE liner goes down into the heartbreak and butts against the nozzle. This style is very easy to print PLA with, but can't print hotter than about 240 °C.
Makerbot MK10
A variant of the lined hotend is the Makerbot MK10, where the PTFE goes a bit into the nozzle. These nozzles have a larger diameter, the melt zone is very short.
All Metal
There are mainly two designs of consumer all-metal hotend out there at the moment.
E3D v6
Stereotypical by now, the All Metal hotend typically means E3D v6. The liner ends at the end of the heartbreak, the heartbreak of the original is necked down to reduce heat creep. The design is flawed in that heat creep can't be mitigated completely. While this design can print much higher temperatures than lined hotends, the heat creep can create trouble with PLA.
E3D Hemera
The dreamchild of the v6 is the Hemera (formerly Hermes), which fights the problem of heat creep by drastically altering the coolend design: The heartbreak is even slimmer than the v6 and has very little area outside of the cooling block. This cooling block is fitted with a somewhat stronger fan. In theory this leads to much better cooling in the upper filament path and getting heat creep under control. However, due to the manufacturing stop induced by COVID-19, there are not too many Hemera out in the wild. Some early to mid development information could be gained from Joel and Thomas Sanladerer.
Among the still few reviews I have found is Thomas Sanladerer.
Slice Engineering Mosquito Hotend
Slice engineering went a different way to fight heatcreep in an unined all metal hotend: The heatsink is mode away from the filament path and serves as its own structure. As a downsize, each and every part is pretty much precision machined, making it comparably expensive: without heater, thermosensor, and extruder the bare item clocks in 145$. Claimed benefits are, that the thinner filament path (as it doesn't need to be structural) from a low heat-conducting material reduces heat creep and because we have an unlined filament path it can print at 450 °C, making it one o the highest-rated hotends.
Slice Engineering Copperhead
Currently, the same company is working on the Copperhead, in which they introduce a dual metal construction on necked heatbreak. The name Bi-Metal for this however would be a misnomer: Bimetal is a standing technical term for a strip of metals that, when heated, starts to tilt into one direction because of dissimilar heat expansion. The correct term, which they properly use on their website is Bimetallic, not Bimetal.
Because of the dissimilar thermal behavior, such a setup needs to be designed and machined very carefully, but could, help to dissipate the heat from the filament path and massively reduce heatcreep. The Copperhead as shown currently is offered for preorder with two mounting options, one of them the e3D style groove., which might allow drop-in replacement of a full hotend.
The heartbreak however alone could suffice to get some of the effects, and as the website shows, it would be available as a drop-in replacement part. However, pricing and effectivity remain still to be seen.
Paired?!
At the time of this writing in May 2020, the combination of e3D v6 and Lite6 using the same outer form factor is pretty much unique to them and their clones. The Trianglelab Dragon hotend (a review of it here) uses the e3D v6 Style connector on a Slice Enginering Mosquito Hotend design, making it pretty much paired to the two.
However the main functioning parts of the distinction is the heartbreak being either part of the cooling body and lined or a separate piece. The e3D v6 does use the same M6 threading that is also used in a Makerbot Mk8 and many Chinese clones on many machines [Some are M7, so beware!], and thus one can easily make a Frankenstein Hotend by combining the pre-mounted cooling body with a proper e3D v6 heartbreak and turn the lined into an All Metal hotend.

Do note that many Chinese cloned hotends aren't M6 (for the whole heat break like the E3D heat breaks), although they are E3D v6 clones they are M7, hence my large spare part inventory... The threads for the heater block are indeed M6.

Can't the heat creep issue occur with all sorts of non-PLA materials too? It's probably less of an issue with very high-temp ones though.

@R..GitHubSTOPHELPINGICE it appears, but doesn't hinder the printing in the same way as in PLA.


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How to resume an unfinished project?
I was printing a lid for a box in my Ender 3 pro printer. But I don't know why it stopped printing and moved aside when it does in finished printings. This happened at midnight and I didn't see it until I woke up. In the hope for a resume I didn't remove the finished part from the printer bed. So now how can I resume this printing from where it left. The total width of the lid was 3 mm and it printed 2.4 mm now only 0.6 mm part left to print.

2 questions: did you power down the printer since finding it and what does the screen on the printer show?

First I didn't turn it off and tried to find the resume option in the menu but I couldn't find that and that may mean it showed as if completed but I don't remember the screen now. I was a little sleepy then after not finding the resume I turned it off

if there was a power out, you just need to press the wheel once to get resume... but shutting the machine off prevents any resume.

0.6 mm is not easy to spot: maybe the filament got jammed and the print finished, just the last 0.6 mm were printed out of air?

Provided that the print hasn't come loose from the bed and you know the layer height or layer number (you could count the amount of layers or measure the height of the print using a caliper), you can edit the original G-code file to print the remainder of the print. The following hints should be taken into account:

Don't use G28 or G29 instead use G28 X Y (please note that using G28 or G28 Z to home Z as well, may not work if the print is blocking the homing of Z, e.g. when homing in the center of the build plate)
Manually position the printhead at the correct Z height (place the cold nozzle on top of your failed print when the steppers are not powered, you could leave a paper thickness of a gap in between the nozzle and the print) and instruct the printer to use that height for reference: e.g. when the print stopped at layer 12 with a 0.2 mm layer height (2.4 mm height or use the measured height with a caliper) define G92 Z2.4
Make sure the hotend is primed before resuming printing
Cut all the G-code present in the file prior to the layer you want to start printing (e.g. search for G1 Z2.2), but do add bed and hotend heating, e.g. respectively M190 S60 and M109 S200

What you can also do is:

Reprint the whole print
Re-slice the print where you have sunk the print 2.4 mm into the bed in the slicer just printing the top face which you glue on later (this works only if the print is exactly at the same position as the initial slice, preferable the project was saved in the slicer or the default position after inserting the print object is used, note that this is difficult to reproduce when multiple objects were place on the bed, it would be better to edit the existing G-code instead!).

Note that you will always see a difference in appearance compared to an object printed in one session, you will see an interface line between the first and the second part.

Thank you very much for all information. A last question, I use Cura for slicing. How can I only choose the top part in an object ( which is the part left after that 2.4 mm) and print only that?

@asduskun If you drop the STL through the build plate in Cura (you might need to disable snap to build plate option) until the 0.6 mm is left above the build plate. If you slice it, the part under the build plate is omitted upon slicing.

That's pretty much the only way, but acknowledge that the new print might have adhesion problems to the old.


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Printer starts normally then becomes insanely slow
After having replaced the Creality factory firmware by a recompiled one to manage a BLTouch sensor I have the following behavior on my CR-X (mainboard Creality V2.2, firmware Marlin 1.1.6 + additions by Creality for touch screen and maybe merged bugfixes):

the homing and auto-leveling job is done normally (on 9 points for auto-level)
the bed and nozzle are warming
the print starts normally with an adherence skirt (Slicer Cura 4.6.1 / Linux / offline via SD)
on one part (bottom of the picture), the first layer is done normally then on the second layer during filling the advance becomes incredibly slow, maybe 5 seconds/mm, I can count each motor step
on another part (top of the picture), the filling of the first layer does not even finish

I have placed the first part turned by 90° horizontally, and the problem occurs at the same position relative to the part.
I have also noticed that once the advance is slow, even if I cancel the print, manual advance keeps slow.
I have seen that slow printing of circles is a known problem, but the circles are printing at correct speed, the slow down occurs in 45° fillings. An the Knob part is full of curves.
BTW the support for bezier curves is not enabled in advanced config settings.
Could it be a bug in the firmware? The source code published by Creality seems to be a customized 1.1.6 Marlin dating from 2017 with some more recent files (possibly applied fixes) that is supposed to match the built-in one when I got the printer but I never had the problem with stock firmware. Could it be worth to apply the Creality settings to the last 1.1.9?

I remember the same issue on my very old Marlin 1.0, and I never understood why. I don't use Marlin anymore so I can't help.


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Adding custom M or G codes to Marlin 2.0
Adding custom M Codes to Marlin doesn't work for Marlin 2.0
How would one go about adding custom G codes or M Codes to Marlin 2.0? The Marlin_main.cpp file does not exist.
In general for Marlin 2.0, things are organized better, but split into more files.

Choose a code in the >10,000 in case new codes are added. But in this example I will choose 13
Navigate to 'src' folder of Marlin
Edit the file gcode.cpp around line 223 to have a new unused number. For example, this will create a  new G code function for the label G13.

  ...
  // Handle a known G, M, or T
  switch (parser.command_letter) {
    case 'G': switch (parser.codenum) {
      case 13: G13(); break;
      case 0: case 1: G0_G1(
  ...

On line 375 of gcode.h add:   static void G13(); to declare it.

In my case i was reading values from an analog system. So I went to src/temperatures and copied M105.cpp to be G13.cpp. Then inside the file I replaced GcodeSuite::M105 to be GcodeSuite::G13. I am using this to take in the weight of something using a [scale][1] but for now I just want to test functionality so here is my test function:

void GcodeSuite::G13() {

  SERIAL_ECHOPGM(MSG_OK);
  SERIAL_ECHOLNPGM("here is where weights are broadcast");

}

And again this is the only part I changed in my new copy of M105.cpp (a new file named G13.cpp). There is still more stuff in the file than just these few lines.

Upload to board

When going to octoprint and typing in G13 I get:

Send: G13
Recv: okhere is where weights are broadcast

A bit more work can be done to make it look nice, but this was the hard part.
[1]: https://www.instructables.com/id/Arduino-Bathroom-Scale-With-50-Kg-Load-Cells-and-H/

The code in 2.0.x is similar to the old branch 1.1.x, G-code is parsed in gcode.cpp, specifically in process_parsed_command:
void GcodeSuite::process_parsed_command(const bool no_ok/*=false*/)

In the case statement the codes read from the G-code files are parsed (interpreted) and the appropriate method is called (e.g. G28() calls void GcodeSuite::G28())
If you want to create your own codes, it could be an idea to start there. Also think of using a different letter and/or codes in the 10,000 range so that it will not collide with new implemented G-codes.


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Longer LK4 Pro moving to corner mid print
My printer is the Longer LK4 Pro, and I just got it 2 days ago. When I started to print some objects, on a certain layer, the printer would stop and move to the far right corner of my bed. What can I do to fix this?

Hi, welcome to 3DPrinting.SE! Is it instructed to do so? Have you checked the G-code file? Do you know what layer? What layer is it printing, e.g. a very small one, is it happening with all prints? Please add more context to the question, otherwise it will be difficult to troubleshoot.

It's possible that the slicer is using a minimum cooling time per layer and the corner is set as its home coordinates.  In the settings of your printer you can set the home coordinates and in the slicer you can reduce/remove the time between layers.


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The filament is almost impossible to remove
Most people complain about the filament not sticking on build plate but mine is vice versa. At first it used to be very good. When I removed the magnetic bed the project would come off easily but for a few days it is like I glue it to the bed with epoxy. It is impossible to remove and when I remove the black projects from the bed I see white color at the bottom of the object printed. Maybe because of too much force but I don't know why this happens.

Increase the distance between the nozzle and the bed, for hints see this answer.

Had this problem on my second print.  The nozzle was too close to the bed. The only way I got it all off was to heat the bed. Then the PLA became a bit softer and came off pretty fast.

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

You know the very first layer it does around the object. The thin layer. It seems very hard to remove. How can I remove that? It seems like pressed instead of printed

The very first layer it does around the object is called a skirt.
If your build surface if removable then remove it. Use something like a putty knife with a thin and sharp edge to remove the residue particle. Watch this


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Extruder spins for a few seconds after layer changes
Sometimes my Extruder will start spinning pointlessly fast and long.
Youtube Video showing the problem
This Issue only happens:

When printer has finished a Layer and moved up to the next (right after the Z axis has moved)
Not on all, but only on some layers of a print.
Typically it will be more towards the middle of a print, and it will happen on several (maybe 10, 20, or a lot more) consecutive layers

My regular Setup/Stack:

PrusaSlicer-2.0.0+win64-201905201652
Octoprint (Version 1.4.0)
Tevo Tornado (with Mamorubot print-platform)

I have tried to test whether the source of the problem could be Octoprint or the slicer/gcode.
Octoprint:
The problem persists, when i print directly from SD
slicer/gcode:
Here is some gcode, one of a layer change where the problem did occur and one where it was fine:
Problem occured here:
G1 X167.854 Y170.305 E209.95401
G1 X167.851 Y132.289 E210.24063
;BEFORE_LAYER_CHANGE
G92 E0.0
;3.95

G1 Z3.950 F7800.000
;AFTER_LAYER_CHANGE
;3.95
G1 X168.141 Y131.859
G1 F3600
G1 X129.532 Y131.858 E211.24663
G1 X128.945 Y131.592 E211.26340
G1 X128.419 Y131.004 E211.28396

No Problem occured here:
G1 X168.288 Y170.558 E474.06508
G1 X168.224 Y170.259 E474.06950
G1 X168.213 Y131.857 E474.62495
;BEFORE_LAYER_CHANGE
G92 E0.0
;9.8

G1 Z9.800 F7800.000
;AFTER_LAYER_CHANGE
;9.8
G1 X168.559 Y131.441
G1 F3600
G1 X129.622 Y131.440 E475.63947
G1 X129.198 Y131.248 E475.65161
G1 X128.776 Y130.777 E475.66807

I cannot see any problem with the gcode.
Now I am at my wits' end - what could be the source of the problem, and how to I proceed to debug it?

Where is the G92 E0.0 on layer change coming from? Because it looks like you're setting E to 0, but then after moving in the X/Y, your first move has to spin it all the way to 470-something. Are you sure you're not seeing this on every layer change?

Looks like the remnants of a deleted postprocessing that switched to relative mode to do something with extruder then back.

Doing some googling, it looks like the BEFORE_LAYER_CHANGE comment in the G-code and stuff that follow come from the before_layer_gcode setting in your PrusaSlicer profile. Somehow, G92 E0.0 got in there. Remove it and the problem should go away.

The code G92 E0.0 was in the 'before layer change' settings in prusaslicer, I don't know how or why. After removing this, it seems to work wonderfully. I was just really confused, because that problem occured so irregularely, and after the z-axis had spinned, while this code was in there before the z-axis commands.


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Access uncapped 5 V output on 3D printer controller board
Typically in Arduinos, most of the 5 V outputs that have a limited amount of current (40 mA).
Are there any 3D printer boards, or is there even a more usual spot, where you can get a 5 V output that isn't capped by the microcontroller?
I know that USB 2.0 is (typically) limited to 500 mA especally when connected to a laptop. Just wondering if there was a way to for e.g. get a 200 mA output from one of the 5 V pins, or more if there is a stronger power supply connected to the USB port.

I believe the USB port is generally a “device” port, which will not supply power, as opposed to a “host” port, such as on a PC.

That's true and one interpretation of what I said, but i still meant if you had a 3D printer board powered only by USB and not 12V, is there a pin somewhere on the board to get more of the 5V power from the USB?

Any pin that is labeled as "5 V" can supply the full amount of current. Looking at, for example, the Arduino MEGA pinout, we can see several pins labeled in red with "5 V". These are the pins you can use. Most 3D printer boards will expose the 5 V pins at several points. For example, the endstop connectors often have a 5 V pin that can be used.
The pins that are limited to 40 mA that you are thinking of are the digital pins, i.e. the pins that can be switched on/off by the microcontroller. These are actually more limited than this, and while in some cases drawing 40 mA from them may be possible, it is not a good idea.

I have confirmed this. I was confused because I had a fairly common two pin solid state relay (SIGNAL, GND only). And it  could work on the constant 5V pins, but not on the digitally controlled pins, probably because there is less current on the latter, even when the signal is set to high. It is annoying because it can't be digitally controlled unless i add another mechanical relay (defeats the purpose of using a solid state relay) or if I use it at a 12V extruder port (one less heater)

Any 5 V "output" on those main boards would be used to power a USB host. This is because the electronics actually runs on 3.3 volts. It would be better to splice the input power (the 12 to 24 V) and use a buck converter to get down to your required 5 V. Select the right one, and you can have all the current you need.


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Can't create image to G-code software for CNC to process
For the last 3 months I have been working on a CNC drawing machine but to this day I can't get the algorithm for line detection so I came here.
I can't understand only one part and it is CAM the (image to G-code) so I'd be grateful if someone could help.
(I want to create my own software not use any modules)

If I understand correctly, you want to write software that parses an image to G-code rather than using available software. Maybe you should explain why.

If you slice an image, you will get gcode to create a lithophane. If you slice a 3D model, you will get gcode to create a replica of that model. What is your ultimate goal?

Generally, movement in a CNC, FDM-Printer, laser cutter, and Plotter has the XY plane decoupled from the Z-axis in most operations. As a result, the path in the XY plane is in 2D. But how to get to a path? Well, we have 2 variants:
Pixel
Most pictures store information as Pixels: each pixel on a grid has a color assigned to it. Scaling the picture does alter the grid size. These pictures are very hard to plot, unless you have your machine interpret each pixel of a given color as a specific movement operation. For example, each pixel of black color in a monochrome picture could be translated as a square-movement of a certain size, using the top-left corner of the square for the operation's reference. In G-code, drawing a line around the Pixel X=10 Y=10 with a grid size of 1 mm looks like this:
G90 ; absolute mode!
G1 X10 Y10
G1 X1 E1
G1 Y1 E1
G1 X-1 E1
G1 Y-1 E1

Vector
proper 2D-Pathes are stored only in Vector graphics. If you can, Vector graphics can contain the exact path you want your machine to follow. A typical format is .svg. It contains already the start position of path and how to follow it. Going from Vector Graphic to G-code just needs you to add G1 before each part of the path instruction and E commands at the end to operate whatever tool you due - be it spinning the drill in a CNC, extruding filament in a printer, turning on a laser or pushing down the printhead in a plotter.


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TMC5160 Overheating
I am trying to do a project using stepsticks to drive stepper motors. I am currently testing the wiring of stepsticks on a breadboard using a stepper from CD driver and an old laptop charger. I connected it to my old A4988 driver according to this wiring diagram and everything is working how it should.

However, when I tried to swap the driver for the new TMC5160, and use it in STEP/DIR mode, the driver didn't work and one driving MOSFET started to overheat.
My question is what am I doing wrong and is there anything I need to wire up differently? Or is the driver fried?
Before anyone asks I disconnected the power supply and arduino and I double checked the orientation of the driver not to connect it upside down.


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Thermal Stress Cracking During Heat-Up on Glass Heated Bed
About two months ago, I added a heated bed to my custom 3D printer in order to print larger ABS parts for my research project. The heated bed (the PCB kind) was not new, but taken from an old printer I had built, but took apart. The bed worked well for a few weeks, but after one print finished, the glass bed above the heater PCB had shattered into several pieces (represented by bed 1 in the image below) and the nozzle was below the level of the bed (I believed it had lowered into the glass causing the breakage. I haven't determined what caused this motion, but it hasn't happened since). Notably, this print was using the heated bed at 90 °C. I chalked this up to a freak accident, and since it did not happen again, just replaced the glass and kept printing.
However, as soon as the heated bed was activated after the replacement, a small crack appeared on the glass and continued to lengthen as time progressed. I took off the glass as soon as possible and prevented it from fully breaking (see bed 2 in the image below. This bed was smaller as I didn't have access to a large enough piece of glass at the time).
At this point, I figured something more than an impact caused the glass to shatter. Since both cracks occurred when the bed was heating or cooling, I figured that thermal shock could potentially be the source of the cracking, and a quick google reinforced this idea. Due to the nature of both cracks (not being straight shards but meandering around the build plate and propagating slowly), they both appeared to have been caused, or at least propagated, by thermal effects.
To try to avoid future cracking, I took care in assembling the third bed. The heater PCB was attached tightly to the glass with Kapton tape and a thin layer of thermal paste was added as an interface layer to try to get an even contact and heat distribution throughout the glass plate. I made sure that the cardboard shims (which press the glass into the clips) were not too compressed, thinking that pressure in the middle of the glass plate from the shims may have accentuated the cracking by putting the top of the glass under tension.
But after a few cycles with this new bed, the same problem appeared (bed 3 below). This time, the cracking was as severe as the first case, but no impact occurred and I was not touching the bed. The bed was heating up to temperature (90 °C) when the cracking occurred. The strangest part is, the file set to print was one I had already printed successfully on the newest bed.
At this point I am at a loss and don't know what to do next. I don't want to make another bed just to have it crack in a few prints, but I need the bed in the near future. Any suggestions to mitigate this problem would be greatly appreciated.

Update (currently fixed)
I have replaced the bed with a borosilicate glass sheet, switched the heater to a stick-on 120V silicone heater (the same size as the bed), and added a PEI sheet on top. After about 2 months, it is working great and no cracks have formed. My best guess is that it was a combination of poor glass, possibly with small fractures on the edges already since I cut it myself, and the heater which was too small for the bed. Thanks for the suggestions!

The PCB is probably heating up the glass unevenly, I would replace the bed for a new heatbed and invest in proper borosilicate glass as that is more resistant to thermal stress.

Did you blue the glass bed down? Glass and metal have a MASSIVELY different heat coefficient, it is not safe to glue to two together!

The first and second bed were not rigidly attached to the heater PCB, only pressed into it  lightly. On the third bed, I did use thermal paste to attach the glass to the PCB, but it was not a permanent glue-like bond and the two could more relative to each other.

Whatever you do, if you solve the issue please report back

"The heater PCB was attached tightly to the glass" - I suggest that the "tightly" part is the problem. Thermal paste might be included in "tightly" as it could cause too much thermal gradient. One bulldog clip near each corner is enough.

The problem is in the design of your bed. Let's start from the basic setup of a glass bed:
The heater element is usually mounted to a metal carrier, which is both spreading the thermal energy over the bed, but also is the structural element that is leveled against the carriage. Atop that comes the glass print surface.
Now, once the heater element is turned on, the aluminium starts to expand and evens the distribution to the glass. As the glass has a much lower thermal expansion coefficient, it doesn't expand as fast. Because of this, the glass surface should never be glued to the bed or heater but held in position to the metal bed with a clip. This way the thermal and mechanical stress on the glass sheet is mitigated: The metal bed evens the heat transfer and the clip can move its position on the glass.

I just ordered a borosilicate glass sheet from McMaster. When that gets here, I will try adding a metal plate between the heater and the glass. Thanks for your help!

I would be careful before trying another glass just hoping it will go better, since you haven't found the issue.
I have a PCB heated bed in direct contact (PCB copper traces on top) a 2 mm glass (plain float glass, not hardened and not borosilicate). It never broke and I've been using it intensely for the last few months. My heated bed is very flat (even if it bends with the heat) and also clean: no residues which can push against the glass. Clean yours properly!
Also, how powerful is your heated bed? mine is about 120 W for 12x12 cm. If yours is too powerful, maybe you could slow down the heating by reducing the maximum duty cycle (you need maybe to recompile Marlin) or by increasing the temperature 10 °C at time.
I also see that you use mirrors, maybe recovered from other applications. I bought the glass new, which is very cheap but it is also guaranteed defect free. Maybe yours had issues already.

The heater was a part I salvaged from an older printer I built, so it was only 21cm by 21cm while the glass sheet was much larger (closer to 30cm). I think the heater not covering all of the glass surface was the source of the cracking (in retrospect, this was a terrible design choice by me). The outline of the square heated bed is kind of visible in the cracking pattern too. I ordered a larger 30cm silicone heater a few days ago to go with a new borosilicate glass sheet, but it won't arrive for a while. I'll update this when I am able to test that out. Thanks for the response!

@Hyperion31415 I would try the new heater (not sticking, just in contact) with plain glass, so that you can be sure of the cause.

As manufactuer and 3D printing's fans, I think it's better to use custom tempered glass. It will be nice and flat and stiff. It's also easy to clean and holds up well. You can print on the bare glass with many materials or use various preparations like PVA (glue stick or white glue diluted with water are popular), hairspray, or others.


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How to solve burnt blobs on Prusa MK3S (PETG)?
As stated above, I am trying to solve a problem I've had for a long time. Unfortunately, this has recently intensified to the point where it causes layer splitting/detaching from each other. I have tried various ways to fix this and, while decreasing the temperature and extrusion multiplier improved the situation, the problem is still present.
My settings:
Nozzle 235 °C Bed 100 °C
Cooling 25 %
Extrusion multiplier 0.89
Speed 150 mm/s for everything, 50 mm/s for small perimiters
Acceleration 1000 mm/s2, (default)
Layer height 0.15-0.3mm
Line width - 0.6mm for everything, but 0.45 for first layer and 0.42 for top solid infill
Is there a different solution than lowering print speed or buying an E3D silicon sock? I have lost my spare ones and the current one wore down. Obviously, I can simply pause the print when I see plastic bulding up on the nozzle, but I am sure that there is a more efficient solution.
UPDATE: I found that the hotend was very dirty and full of burnt/molten plastic. I am almost sure that the hotend is leaking somewhere between the heat block and the heat break. This didn't happen before I replaced the nozzle. How can I fix this? Do I have to replace the heat break or some other part?

PETG doesn't like to be printed at 150 mm/s usually advised speeds are in the region of 50 mm/s. Could be that because of the speed you build up blobs from left over pressure of the extrusion process which clutter and burn.

@0scar This is exactly what I was afraid of. I have no problems printing PLA, ABS, even Nylon at that speed... What is the highest possible speed do You recommend for PETG? I am working on a project where time is a limited resource, so I need to reduce print time somehow...

@0scar it's also true that the layer height and line width are not mentioned... if thin and low, the volumetric flow would be reduced as well.

@FarO The layer heights I use are anywhere between 0.15 and 0.3 mm. The problem occurs regardless of the layer height (in my case). Line width is  0.45 for first layer, 0.6 for external perimeters, 0.6 for other perimeters, 0.6 for infill, 0. 6solid infill, 0.42 top solid infill. I will include that in the question.

I saw PETG printed at 100 mm/s, but 150! That's a lot.
One solution to avoid blobs may be to limit the maximum speed to a value you can actually achieve with reliable results.
Simple test to find your machine limits (each combination filament brand + nozzle + temperature has a different value): extrude filament in the air at increasing speeds, see how the flow changes, and when you see more than 5% decrease, that's it.

M83
mark the filament as if you were calibrating the E steps
calculate filament speed: speed = volum/s / filament surface * 60 = mm^3/s * 25 (this factor is valid for 1.75 mm filament)
set extrusion speed for 2 mm^3/s: G1 F50
extrude 50 mm: G1 E50
measure actual length extruded
repeat 2.-6. but increase the speed by 2 mm^3/s each time: 2, 4, 6, 8, 10, 12, ...
at a certain speed you will see that the actual filament length starts to decrease. When you see that the underextrusion reaches 5-10% (depending how much underextrusion you accept), write down that volumetric speed (mm^3/s) somewhere, it's your limit for THAT filament + THAT nozzle + THAT temperature
Either a) calculate the max print speed = volumetric speed / layer height / line width or b) set the maximum volumetric flow rate in the slicing software so that the speed will be automatically capped taking into account layer height and line width. Prusaslicer allows to set that in the "Print" or in "Filament" settings, I recommend it for "Filament" settings, since it's a filament-dependent parameter.

Example data from CNC Kitchen:

You can increase the max print speed, at the price of a little loss of quality around edges, if you calibrate the E steps at a speed corresponding to 2-3% underextrusion (alternative: to the speed of outer perimeters).
This way you know that when you print slower than that (uncommon... typically only sharp corners and small perimeters) you'll get up to 2-3% overextrusion, and you extend by 2-3% the maximum print speed, since your max speed is the one where you get 5-10% underextrusion compared to your E steps calibration speed.

For info: if anyone perform that sequence to test the capabilities of their printer, please post the values here because I'm curious about the performances of various extruders.

This seems interesting. I'll give it a try and let you know.

Even not extruding anything but just performing travel moves over PETG at 100 mm/s or higher will tear it up and drag material all over the place. The result is blobs stuck to the nozzle, possibly even stringing, and choppy lines that the next layer will not properly adhere to. PETG simply cannot be printed at these kind of speeds regardless of how fast your hotend can melt it.
Turn all speeds, print and travel, down to 40-50 mm/s, then experiment to see if you can increase them at all.
Note that if your acceleration is only 1000 mm/s², you're basically never going to reach the desired 150 mm/s anyway, so this probably won't be as much of a slowdown as you expect. Jack the acceleration up as high as your machine can handle and it might still print as fast or faster, but without the blobs.


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Print gets worse with every layer - Ender 3
First of all, I'm still new to this 3D printing and I've bought myself a second hand Ender 3 with some mods done to it.
I've successfully printed with PLA in different colors but after a good first layer the print seems like it is skipping lines.
I've already tried to:

Change the nozzle
Set the bed level (like a million times)
Download calibration files (e.g calibration squares)

I have used Cura with the Ender 3 Pro profile:

I print in PLA at 200 °C
A print bed temperature of 60°C
Cooling fan at 100%
Layer height of 0.2 mm
Line width is 0.4 mm from a 0.4 mm nozzle
Printing Speed is set to 50 mm/s for walls and 25mm/s for infill
Retraction is 6.5 mm/off at 25mm/s

I really don't know how to fix it the bad quality.

does different filament do the same thing? does slowing down the printing help? also try without cooling fan.

Have you changed any other settings in Cura?

try filament diameter and also check the height axis steps per mm.

Many questions on 3D Printing SE are answered, at least by me, not with a "this is the problem", but instead, this is how I would analyze it.
Looking at the picture you supplied, there is something strangely periodic about the under-extrusion in the top visible flat layer.
I don't think it is an X or Y axis problem.  It is too low-frequency to be an extruder drive problem, such as a slippery drive hobbed gear.  It seems too high frequency to be a filament feed problem, unless you are very close to the end of a spool with a small inner diameter.  This is less likely because you have printed many things, and I would infer that you have seen this with full spools and empty ones.
The Ender 3 looks like a Bowden-fed printer.  You are printing PLA, which should work well with Bowden.
Temperature variation could also cause this problem.  If the nozzle were cooling and heating in an unstable control cycle, where the nozzle is cooler you would find under extrusion and even non-extrusion.  This looks compatible with the results.
What could cause thermal problems?

Not delivering energy to the heater, perhaps because of a bad
connection, or perhaps because of an intermittent heater cartridge
Not sensing the temperature correctly, perhaps because of a shorting thermister
Thermal control look is out of tune, which I consider unlikely since you haven't messed with it, and in my experience that is pretty forgiving
Not conducting heat from the heater to the nozzle, which is unlikely

If you have an infrared thermometer, put a piece of masking tape on the heater (to get a consistent IR emissivity) and monitor the temperature.  Is it cooler when under extruding?  It might only be a few degrees different, but that could be enough if you are right on the transition temperature.
If the temperature is stable, you might try printing 10 degrees hotter, just to see.  Some variation is normal, and you might be on the edge.
It is possible you have a filament that widely varies in diameter, but for that strong an effect, you would have noticed that the filament was thinner in some places than others.
My best suggestion is to look at temperature.
Further Reflection
It is also possible that you have something dragging on the filament spool.  I don't like it as a solution, but it is consistent with printing a lot (at the beginning of spools) and then encountering this problem.  A problem feeding, although I discounted it in my earlier answer, could produce a periodic under-extrusion if the drag on the spool changes.  If the problem was one-time, then it may have been bad winding in the spool so that once per revolution it requires some extra tug to unwind the filament.  That tug would reduce the torque available to push the filament through the working side of the printer.  There might be extruder jumps (pops, clicks, etc.) coming from the extruder as it skipped steps.

The problem OP is seeing is not something that should be possible as a result of subtle continuously-variable settings like temperature, unless the thermistor is very messed up. My guess here would actually be a slicing problem - wrong/missing retraction, coasting, or other bad settings that produce misplaced or under extrusion.

I'd suggest running through basic maintenance.  Check

Is the nozzle clean/unblocked?  If not clean it out
Is the nozzle worn?   If so, replace it
Is the bowden tube okay in the hot end ?  If not, replace, or at least shorten it.
Are your e-steps calibrated correctly?
...etc

Also consider whatever mods were made, and whether they help or not.  There's a chance something there was sub-optimal, which is why it was sold off by the previous owner.

I had this exact issue - PLA wasn't sticking to itself. It was intermittently being dragged around by the nozzle, and prints literally fell apart when removing them.
The problem: bad filament. I bought a new roll and the printer worked fine afterward.

while bad filament can be an issue, it can also be bad settings for your filament: wrong temperature or flow can make a perfectly good filament appear bad. I have had spools where a difference of 5°C  in my getting settings made the difference between a perfect (195°C) and a crap (200°C) print!


text:
Deltaprinter scratches print
About a year a go I bought a Tevo Little Monster second hand. It was a little dirty but (as far as I could see) unmodified. I put away that noisy "MKS SBASE"-board with smoothieware and installed a nice Duet 2 Ethernet board. I tried for weeks to get it going but without success, then decided to try it again later.
Now I am on it again and already put a lot more effort in it than last time. Anyway, the problem persists and it is really driving me nuts!
Out there on the internet are several people who succeeded with a duet board on the same printer, so it must be possible. For Example this one.
My Background
I am doing 3D printing for a while now. Besides the Little Monster I own a Makerbot Replicator 2X (running latest Sailfish), a Anycubic Delta Linear Plus (running self-compiled Marlin 1.1.9) and – for two weeks now – a Two Trees Sapphire Pro (running self-compiled Marlin 2.0.x). All these printers are running absolutely fine.

Problem
As far as I can tell, my problem boils down to inaccurate z positioning of the nozzle.
This makes the nozzle (heavily) scratch on printed parts of the same layer. Small parts are often ripped of the bed by the nozzle before the print is finished. Practically I cannot use the printer in its current state.
Here is a video of the Problem.

Test setup
My usual test scenario is a 100 x 100 x 20 mm box with two walls, two top/bottom-layers and 50% Infill. Maximum Speed 90 mm/s. The speed should be fine, as the printer is advertised with 300 mm/s.

What I changed from stock:

Install genuine BL Touch
Changed controller board from stock "MKS SBASE" to Duet 2 Ethernet
Removed sticker from printbed and placed a UltraBase (310 x 310 mm) on top of the stock glas plate
Replaced stock titan-ish extruder by cloned BMG dual drive Extruder (same extruder as on all of my other printers)
Replaced full-metal hotend by a hotend with PTFE liner

What I already tried to solve the problem:
Hypothesis: Bad config of duet board
Actions: see separate section
Hypothesis: Narrow nosed nozzle does not smooth the printed line enough
Actions: replaced narrow-nosed nozzle (0.6mm) by broad-nosed nozzle (0.4mm) and adjusted cura accordingly
Result: No difference
Hytothesis: There is something wrong with the firmware
Action: Upgraded duet board from RepRap 2.0 to 3.0
Result: No difference
Hyptothesis: Geometrical inaccurate build
Actions: Measured arm space on effector and carriages (by caliper), "measured" rod lengths by eye (b/c my caliper can only measure about 150mm), checked towers by eye for bending.
Result: Arm spacing on effector and carriage is the same down to 0.19mm. Rod lengths have no noticeable difference, towers seem to be straight.
Hypothesis: Joints on delta Rods have play
Actions: Tried to shake/move/wiggle the effector by hand
Result: No noticeable play
Hypothesis: Overextrusion
Action: Intentionally underextruded (80% flow) for testing
Result: Printed lines became noticable more narrow (not even touch each other), but scratching persists.
Hypothesis: Rubber wheels of the carriages running too rough and are worn out
Action: Replaced rubber wheels by linear Rails. (Thingiverse)
Result: Carriages run much smoother, but this change does not help with my problem
Hypothesis: Belt tension is bad
Action: Tensioned the belts thoroughly
Result: No noticable difference
Hypothesis: Tooth belts are worn out
Action: Replaced tooth-belt with new GT-2 Belt
Result: Belts look more regular when moving, does not help with my problem
Hypothesis: Pulleys and Idlers are worn out or not sufficiently round
Action: Replaced Pulleys and Idlers
Result: No noticable difference
Hypothesis: One or more of the stepper motors are not working properly
Action: Replaced all tower motors (incl. wiring) with new ones
Result: No noticable difference
Hypothesis: One of the stepper drivers is not working correctly
Action1: Investigation of signals on the motor-wires by oscilloscope
Result1: They all looked about the same (short square pulses), in principal no difference between all motor wires. (I do not know how these signals should look like. I just tried to spot differences.)
Action2: Changed the drivers for the tower motors one by one with the unused E1-driver
Result2: No noticable difference
Hypothesis: Leveling is bad due bad probing
Action1: Checked leveling manually (with feeler gauge) and checked BL-Touch repeatability.
Result1: Found deviation of 0.2mm on some points between automated and manual leveling. Repeatability is good (accurate to 0.02mm)
Action2: Leveling is now done by a DF9-40 weight-resistor (and a voltage divider). This sensor is mounted (manually every time) directly under the nozzle.
Result2: The first layer is next to perfect. To my understanding that means a correct calibration.
Hypothesis: Flying extruder is too heavy and impacts the accuracy of the carriage movement
Action: changed extruder from flying to remote, mounted on one of the towers
Result: Problem seems to hit maybe a little less. I am not entirely sure about this.
Hypothesis: My problem is no problem, a little scratching is nothing unusual
Action: Tried the same print on my smaller Delta printer
Result: No scratching on the other printer. Hence it seems not to be usual.
Hypothesis: Scratching is related partial overextrusion due to "extrusion delay" caused by bowden system
Action: Tested linear advance between 0 to 1.2
Result: linear advance seems to work as intended (watching the extruder), but does not change anything on my problem

Configuration
I tried to transfer the settings from the original smoothieware config-files as good as possible. Original smoothieware files can be found here on github
To have a consistent config, I used the RRF Browser Config Tool.
Motor Current:
There is no advice printed on the original motors concerning the current. Smoothieware config file says 1.5 Amp. Thats what I configured. (The Replacement-Motors came with a data sheet, they can take 2 Amp. So they got 2 Amp)
Steps per mm:
On all tower motors there are 20-tooth-GT2-pulleys. RRF Config tool suggests 80 steps/mm (with 16x microstepping). I tried it with and without interpolation from 16x to 256x and with "native" 256x microstepping (1280 steps/mm). Also tried native 32x microstepping with 159.53 steps/mm (like in the smoothieware config) and 160 steps/mm. Does not change anything on the problem.
Delta Parameters:
Original Smoothieware config suggests:
arm_length      397.1900            # This is the length of an arm from hinge to hinge
arm_radius      157.0741            # This is the horizontal distance from hinge to hinge when the effector is centered

That seems to be (roughly) consistent with what I measure by folding ruler. So that is what I put in my config right away.
Auto Calibration:
Tried 4,6,7,8 and 9 factors (using the force-sensor, not BL Touch) and put the results into splunk. Each data point is averaged over 3 calibration runs with exactly the same settings, every time starting from the smoothieware stock-values. (First run was with 159.53 steps/mm, second with 160 steps/mm)

Surprisingly the auto calibration finds reliably the same parameters, which differ from the stock-config ones. I have no Idea why, but similar things happen on my smaller delta printer. Hence I do not consider this a problem.
Speed and acceleration:
Lowering acceleration (down to 300 mm/s) does not change anything. Lowering speed makes scratching less loud, but still hearable/feelable rumble from the nozzle on the print. Prints are still ripped of the print bed.
; Configuration file for Duet WiFi (firmware version 3)
; executed by the firmware on start-up
;
; generated by RepRapFirmware Configuration Tool v2.1.8 on Fri Apr 24 2020 17:00:42 GMT+0200 (CEST)

; General preferences
G90                                            ; send absolute coordinates...
M83                                            ; ...but relative extruder moves
M550 P"jKossel19"                              ; set printer name
;M665 R157.0741 L397.19 B155 H522               ;
M665 R170 L397.19 B155 H525            ; from forum.duet3d.com with modified hight 520 ==> 525
M666 X0 Y0 Z0                                  ; put your endstop adjustments here, or let auto calibration find them

; Network
M552 S1                                        ; enable network
M586 P0 S1                                     ; enable HTTP
M586 P1 S0                                     ; disable FTP
M586 P2 S0                                     ; disable Telnet

; Drives
M569 P0 S0                                     ; physical drive 0 goes backwards
M569 P1 S0                                     ; physical drive 1 goes backwards
M569 P2 S0                                     ; physical drive 2 goes backwards
M569 P3 S0                                     ; physical drive 3 goes backwards
M584 X0 Y1 Z2 E3                               ; set drive mapping
M350 X16 Y16 Z16 E16 I1                        ; configure microstepping with interpolation
M92 X80 Y80 Z80 E418.00                        ; set steps per mm
M566 X480.00 Y480.00 Z480.00 E1200.00          ; set maximum instantaneous speed changes (mm/min)
M203 X240000.00 Y240000.00 Z240000.00 E1800.00 ; set maximum speeds (mm/min)
M201 X1000.00 Y1000.00 Z1000.00 E1000.00       ; set accelerations (mm/s^2)
M906 X2000 Y2000 Z2000 E800 I30                ; set motor currents (mA) and motor idle factor in per cent
M84 S30                                        ; Set idle timeout

; Axis Limits
M208 Z0 S1                                     ; set minimum Z

; Endstops
M574 X2 S1 P"xstop"                            ; configure active-high endstop for high end on X via pin xstop
M574 Y2 S1 P"ystop"                            ; configure active-high endstop for high end on Y via pin ystop
M574 Z2 S1 P"zstop"                            ; configure active-high endstop for high end on Z via pin zstop

; Z-Probe BLTouch
;M950 S0 C"exp.heater3"                         ; create servo pin 0 for BLTouch
;M558 P9 C"zprobe.in+zprobe.mod" H5 F120 T6000  ; set Z probe type to bltouch and the dive height + speeds
;G31 P500 X0 Y20 Z0.45                          ; set Z probe trigger value, offset and trigger height
;M557 R140 S45                                  ; define mesh grid

; Z-Probe MANUAL
;M558 P0 H5 F120 T6000                          ; disable Z probe but set dive height, probe speed and travel speed

; Z-Probe weight resistor
M558 P1 C"zprobe.in" H5 F60 T6000              ; set Z probe type to unmodulated and the dive height + speeds
G31 P500 X0 Y0 Z0.05                           ; set Z probe trigger value, offset and trigger height

; Heaters
M308 S0 P"bedtemp" Y"thermistor" T100000 B4092 ; configure sensor 0 as thermistor on pin bedtemp
M950 H0 C"bedheat" T0 Q10                      ; create bed heater output on bedheat and map it to sensor 0
M143 H0 S120                                   ; set temperature limit for heater 0 to 120C
M307 H0 B0 S1.00                               ; disable bang-bang mode for the bed heater and set PWM limit
M140 H0                                        ; map heated bed to heater 0
M308 S1 P"e0temp" Y"thermistor" T100000 B4092  ; configure sensor 1 as thermistor on pin e0temp
M950 H1 C"e0heat" T1                           ; create nozzle heater output on e0heat and map it to sensor 1
M143 H1 S280                                   ; set temperature limit for heater 1 to 280C
M307 H1 B0 S1.00                               ; disable bang-bang mode for heater  and set PWM limit

; Fans
M950 F0 C"fan0" Q500                           ; create fan 0 on pin fan0 and set its frequency
M106 P0 S1 H1 T50                              ; set fan 0 value. Thermostatic control is turned on
M950 F1 C"fan1" Q500                           ; create fan 1 on pin fan1 and set its frequency
M106 P1 S0 H-1                                 ; set fan 1 value. Thermostatic control is turned off

; Tools
M563 P0 S"Vulcan" D0 H1 F0:2:1                 ; define tool 0
G10 P0 X0 Y0 Z0                                ; set tool 0 axis offsets
G10 P0 R0 S0                                   ; set initial tool 0 active and standby temperatures to 0C

; Custom settings
; set heater parameters
M307 H0 A213.8 C593.5 D3.3 S1.00 V24.6 B0
M307 H1 A513.6 C184.3 D8.4 S1.00 V24.4 B0
M572 D0 S0.5 ; pressure advance

; Miscellaneous
M501                                           ; load saved parameters from non-volatile memory

Workarounds:

Yes Z-hop helps, but only with travel moves. That is no solution, only a partly working workaround.
No infill with crossing lines: Yes possible, but no: i want a sturdy infill.

What I still do not understand:

Measurements are subject to statistical errors. Marlin (on my anycubic delta-printer) fights this by probing the same point multiple times and taking the average for calibration. As far as I could find out, RepRap firmware does not support this. Is that correct? Is there any good reason? I am quite sure, calibration accuracy would get a little better with this.
Does a perfect first layer really mean accurate calibration of the delta-parameters? Is there any other way i can be sure?
I really would like to know more about the effector tilt. But a bubble level does not offer enough accuracy. Is there any good way to measure this?
I am absolutely not sure about this, but I remember very faintly not to have this problem when printing with the original smoothie board on a completely unmodified printer. But I only made one or two test prints with it. Sadly I cannot test it anymore, because I do not have the smoothie board anymore.
In the very first place I made a mistake with wiring of the motors to the duet board and shorted at least one motor output. (Duet board told me so, I corrected my mistake. Afterwards everything seemed fine.) Might I have damaged my duet board in a way that might cause my problem?
There are parameters in the smoothie config that I cannot find in the duet config. Neither could I find why the duet config does not need these parameters.

mm_max_arc_error
mm_per_arc_segment

Auto calibration finds (repeatable) delta parameters that do not match the smoothieware config, mainly rod length and delta radius. Is there any difference in definition? The numbers from the original smoothieware definition seem to be more consistent with my (quite unprecise) measurements (down to 1-2 mm). I actually know this behavior of "too long" calibrated push rods from my Anycubic Delta. But it does not seem to cause any problems there.

EDIT
Recently tried:

changed duet board for a new one (yes I bought a brand new one)
used different slicer (Slic3r instead of cura)
started from scratch with a new config

Result:
problem persists and has not changed noticeably.

Finally I found an solution. But I still don't know what exactly the problem was.
In my case the problem vanished after the following steps:

replace stock effector with Duet Smart Effector
replaced stock push rods with Magballarms
used custom carriages on the towers


text:
Prusa MINI 0.6 mm nozzle print fail
Setup:

Prusa MINI with 0.6 mm Nozzle.
Firmware 4.0.5
Bootloader version 1.0.0
Buddy board 1.0.2
Prusa Slicer 2.2.0
Using the OctoPrint 1.4.0 on OctoPi 0.17.0 with serial
connection.
Find the G-code here
The amf is found here

After I switched to the 0.6 mm Nozzle I have massive problems to get good results, as you can see in the picture below. The two parts in the front starting to have from the height of about 5 mm very bad lines. I realized it 5 mm later and I set manually the temperature from 215 to 220 °C which seemed to solved the problem a little bit, but still not perfect results.
As you can see in the second picture, I removed the 0.6 mm nozzle to make sure it fitted. I did, there is no filament on the thread.
Test: I did use some noname filament with the 0.6 mm nozzle first and had bad results as well. The problem mainly was, that the temperature (215 °C) was too low. So I raised it for the noname filament to 240 ° which seemed to solve the problem but quality was not perfect, so I switched to the Prusa Polymers filament to make sure the issue is not related to the filament.
So what could be the issue here?

There are strong indicators that the problem is related to the flow rate setting.

So, what speeds are you printing then?

authors: როსტოშვილი დავით


text:
Filament getting stuck after 1.5 hours of printing
Problem: After about 1.5 hours of printing on my modified Anet A8 the (converted to Bowden) extruder begins to make a clicking noise. The filament is not being pushed through the hotend (E3D V6, it is an all metal hotend, and the cooling is out of the box, the heat break is inserted with thermal paste) any more.
Done so far: I experienced, that if I were to retract the PLA 10 mm and then restart the print, it would run a print fine, but the it starts all over again. I already disassembled the complete head and clear out the nozzle.
Thoughts: I think it must have something to do with the slicing settings, because if I change the flow, I can cause the problem to occur earlier. The filament is also pretty cheap and has been exposed to air a year or so...
My Settings:

Layer Height: 0.2 mm
Infill: 40 %
Hotend Temperature: 190 °C
Build Plate Temperature: 45 °C
Diameter: 1.75 mm
Flow: 70 %
Retraction: true
Retract Speed: 100 mm/s
Retract Lenght: 3 mm
Print Speed: 60 mm/s
Travel Speed: 120 mm/s

This sounds like heat creep? (Although this is usually not recoverable by a large retraction...) One thing that bothers me is that the flow percentage is 70 %; how is that possible, a well tuned extruder should operate at a value of 100 %. Retraction speed default is usually a bit lower, e.g. 25 mm/s.

@0scar  If I increase the flow to 100 % the extruder starts to constantly click after the first layers...

This sounds as if you haven't calibrated the new hotend? Do you use a different extruder? Is it able to provide enough force to push the filament through the Bowden tube? Never just change the flow modifier other than a few percent, if more is needed it hints to an incorrectly functioning extruder.


text:
How to add a proper fillet to corner of a cuboid in Fusion 360?
I am a total beginner to Fusion 360. I need to add a fillet. Look at the picture to get better idea.

There are probably many ways to do this, this method describes how I do this.
First you need to fillet the top, then you chamfer the edges.
Create a lid:

Fillet the corner edges:

Chamfer the lid edges:


text:
Auto bed leveling offset issue
I'm using an Ender 3 with a new upgraded board SKR 1.3 Marlin bugfix 2.0 auto bed leveling I use EZABL.
for the EZABL I followed their tutorial for Marlin 2.0 since I don't use the unified firmware.
Offset info :
#define NOZZLE_TO_PROBE_OFFSET { 50, -2, 0 }
#define MIN_PROBE_EDGE 20
I did try to follow this helpful guide
I don't know much about programming so when he said:

"As this is the part that defines the array values, you first need to make an array (note that this is a simple solution that many people should be able to understand with limited programming skills, more elegant solutions use the XYZ struct to access the X, Y or Z properties):"

constexpr int nozzle_to_probe_offset[] = NOZZLE_TO_PROBE_OFFSET;
#define PROBE_X_OFFSET_FROM_EXTRUDER nozzle_to_probe_offset[0]
#define PROBE_Y_OFFSET_FROM_EXTRUDER nozzle_to_probe_offset[1]
I don't understand where to put the lines above and what value to put.
update:
error message on compiling

Config.h : https://pastebin.com/w7CC5eaC
Config_adv.h : https://pastebin.com/qep34T1h

Please look into the guide again it is updated to the latest version.

You do not need to adjust the area yourself for Marlin 2.0, please look into probe.h and into this answer.
You only need to enable the offsets:
#if PROBE_SELECTED && !IS_KINEMATIC
  #define MIN_PROBE_EDGE_LEFT MIN_PROBE_EDGE
  #define MIN_PROBE_EDGE_RIGHT MIN_PROBE_EDGE
  #define MIN_PROBE_EDGE_FRONT MIN_PROBE_EDGE
  #define MIN_PROBE_EDGE_BACK MIN_PROBE_EDGE
#endif


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

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

so I just need to remove the M104 S... that was simple, thanks a lot. I will do it tomorrow


text:
How can I print to my FLSUN QQ over Wi-Fi?
I want to be able to control my FLSUN QQ over Wi-Fi and don't have OctoPrint or a Raspberry Pi to run it on.

Assuming you use Ultimaker Cura to slice, there is a MKS plugin that allows connecting to the MKS WiFi module that comes with the QQ. Just follow these steps:
Install the MKS WiFi Plugin

Open Cura
Click "Marketplace" in top right
Select "Plugins"
Scroll down to find the "MKS WiFi Plugin"
Click on the plugin.
Click "Install"
Restart Cura (quit and reopen)

Configure WiFi

Turn on your QQ
Tap Settings
Tap WiFi
Enable WiFi
Note the IP address and network name
Connect your computer to the printers network
Open your browser
type the IP address of your printer into the address bar
hit enter
Scroll down to "WIFI Configuration"
Select STA
Enter your home network SSID into the field labeled "WIFI"
Enter the password into the field labeled "KEY"
Click configure and reboot

Setup your printer in Cura

Open Cura
Open settings > Printer > Manage Printers...
Click "MKS Wifi"
Click "Add"
Enter the new IP address of your printer (can be found by opening WiFi settings on the printer)
Click Ok
7, Click connect.

Now you should be connected to your printer. After slicing you should have the option to "Print over FLSUN..." In the Monitor interface you should have some other options such as sending commands to the printer, and printing any files already on the SD card, as well as uploading gcode files to the SD card.
Happy Printing

In case you update the printer's firmware to connect to my local wifi network I had to calibrate it again (using the auto-leveling kit). Also, I had to flash the printer twice for the auto-leveling functionality to work properly.

It's already in STA mode, how do I get it to open an access point?

As the auto-install from the Marketplace described in this answer wasn't working , I did have to manually install the MKS WiFi plugin on my Mac (M1 MBPro).  To do this I just:

Downloaded the GitHub files (from the plugin webpage, linked in the Marketplace)
Right-clicked the Cura icon in the Applications folder, to show
package contents
I then went into the macOS folder and followed the plugin link
Copy the downloaded GitHub files
Restart Cura

I then just followed the printer setup advice in Cura from this answer.
No more messing around with SD cards :)


text:
Monoprice MP10 Mini, can't get a decent print
Update: if i press the button "Home" it will correctly posizionate the nozzle above the printing bed, with a gap wide enough to insert a sheet of paper between the nozzle and the surface.
But, and here's the strange thing, if i move the printing bed the z axis motor will rotate causing the nozzle to get too close to the surface, scratching it.
I recently bought my first 3D printer, a Monoprice MP10 Mini. Unfortunately not a nice choice so far.
I calibrated the printer 3 times and after every print the Z axis seems to be completely off.
As a consequence, it scratched the printing bed many times.
On top of that it seems I can't get a decent print anymore, I don't know how I can describe this problem, so just look at the pictures:

It looks as if your magnetic print surface is not flat anymore. Could also be a problem with the rollers of the non driven vertical axis.

Put a straight edge on your plate ... agreeing with @0scar ... it isn't flat.

I thought the same, but it's not just that, there's something wrong with the auto leveling too, I updated the original post. Even during auto leveling, the vertical motor is moving, causing the nozzle to get too close to the surface


text:
Issue with the new heating cartridge of my 3D printer
Recently I had an issue with my heating cartridge, and I decided to change it.
For my Anet A8, I needed a 12 V 40 W one. I ordered it but I received a 15 mm length instead of 20 mm length heater element, but as the characteristics where the same I thought that it should not be an issue!
When I finally tried it, it was not able to reach the commanded temperature. It's like 175 °C instead of 195 °C.
I don't understand why it's harder for the newer heating cartridge to reach the commanded temperature, is the length important even if it's the same power (12 V and 40 W) ?

Try to measure the resistance - does it have the expected 3-4 Ohms for a 40W 12V cartridge?

It might be the wrong cartridge

If it is 40 W then it shouldn't matter what length it is. Note that the heater cartridge just contains a Nickel-Chrome wire-resistor (see image below for the construction), this resistor gives its heat to the metallic shell, the length of that shell shouldn't matter, it usually contains heat free/colder zones at the tip and root. Even if it is a 30 W heater cartridge it should be able to get to temperature, it would just take longer.
If it is a 24 V, 40 W cartridge, operating at 12 V, then the effective power would be $40[V] \times \frac{12[V]^2}{24[V]^2}=10 [W]$. This might be too low to reach the temperature. It is best to check the resistance of the heater element with a multitester; it should be about 4 Ω for a 12 V heater cartridge and about 14 Ω for a 24 V heater cartridge.

authors: ɴᴀᴢɪʟᴀ ᴋʜᴀʟᴇᴅɪ


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DRM or license management solution for 3D printing
Is there any DRM or license management solution for 3D printing? I'm looking for something, that would help me limit the number of prints someone can make from my projects. Basically, I would like to sell the "right to make no more than X copies" of my design. I don't expect it to be bullet-proof (like Widevine L1 for video), but it should at least help me with license management.

Good luck with that.
Issues you will face:

using a G-code editor (or built-in printer software) to create multiple copies of the object in a single print session
user writing the printer file to an SD card, then block-copying the SD card
defining a "print". Specifically:
is #2 another functional copy of the object, or did #1 fail? Failed prints happen a lot.
is #3 another functional copy of the object, or was #2 damaged in post-processing? Like removing supports or left it in the acetone 5 seconds too long and it's now a blob.
is #4 another functional copy of the object, or was #3 tossed because the guy running the printer grabbed the wrong spool and made a perfectly good print in the perfectly wrong material/colour.
is #5 another functional copy of the object, or was #4 damaged in shipping?

The whole process is one-way. There just isn't a path for anything other than the end user to know what they pulled off the print bed. Unless you make the entire process from design software to printer you won't change that. And good luck selling it, 'cause the user base is rather strongly opposed to that kind of thing. For example, ANY kind of DRM in the product, from printer software to filament, is an immediate no-buy for me. I don't care if you are paying me to take it, I will find an alternative without that particular annoyance. And no, I don't use Microsoft or Adobe products either.

Yes, a "full stack" solution from software to printer would be an option, the problem is I don't know any. I'm not interested in selling the DRM solution, I basically need a "safe" path between my business and another one. We are already working together, we just need to add some "accountability".

"a "safe" path between my business and another one" -> that's easy. Contracts. Have your lawyer and their lawyer play tennis.
Also, it would have helped greatly if you specified the scope you were looking for. A "one-to-one" scope is much different from the "one-to-mass market" scope.

Generally: No
Let's face the obvious problems of the files exchanged and the files used for printing, and then look into why it is a bad idea in the first place.
G-code
G-code is in its design a .txt file that contains specific orders for a machine. There is a g-code command that forces the printer to delete the file (M30) but that needs the exact file path - and just does nothing if the path is incorrect. One could make a slicer profile, that after printing, deletes the file from the SD-card, but doing so as a user is only useful for one-off jobs and it can be prevented by the user by simply shutting down the printer before the line is triggered.
Because .gcode is essentially a .txt without any special features but a custom ending, it can't provide DRM beyond containing a self-delete-after-completion.
STL & OBJ
STL and OBJ are the most relevant exchange files. They are open source and not intended to contain any DRM.
Other formats?
Even with a different format, you would need both a proprietary 3D format that can only be read by your DRM-enabled slicer as well as a proprietary printer file type that both contain DRM. However, using a proprietary printer command type means you lock down your file to be only available to your printer family, which in turn makes this printer family less desirable, as it can't work with the standard g-code format.


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Is it possible to upgrade the CR10-S Pro to CR10-S Pro v2?
What I really want to do is to upgrade hardware components to support 'print recovery' after a power outage.

That's an option you need to activate in the firmware.

Print recovery can be achieved by changing the firmware.
Here is some information on how to do that: Marlin documentation
Also, this another stackoverflow post about that: Stackoverflow Post