text:
Cleaning IPA with the help of Mercury wash-and-cure?
I have seen that you can clean used IPA from resin by putting it in the sun a while, making the resin dissolved in the IPA cure. Could I do the same thing just using the cure-mode in with the Elegoo Mercury wash-and-cure-station?

Which wash and cure station? There are a bunch on the market. Technically you could replace sunlight with a UV LED

Based on the frequencies of most UV cure resins, your suggestion has merit. Other factors come into consideration, however.
These illumination devices have a limited life span. Running the UV diodes for the purpose of curing out the resin from the IPA will "use up" the portion of time otherwise useful for curing models.
Additionally, the UV light which would otherwise be "applied" to the surface of a printed model now has to pass through the IPA. While the IPA is perfectly transparent to the 405 nm used to cure resins, there could be attenuation and refraction by impurities in the liquid.
Sunlight is mostly free, broad-spectrum, and (on a sunny day) far more powerful than most affordable UV illumination systems.
In a pinch, sure, use the curing feature, but the sun is your cheap friend.

Thanks for good comments! I will try to find a better solution than using the curing station. I can try the sun, but I live in sweden. It's autumn/ winter here. i haven't seen the actual sun in a week. The few hours it's up it's mostly cloudy :-P

There are a number of "ordinary" UV lamps that will not be as expensive and will accomplish the desired result. Some of them could be considered nail salon curing devices. One other option is to look for a simple UV tube and build a mount for it, with your skin and eye safety in mind.

@Ulf a UVA light bulb for curing fingernails also hits the 400 nm band that we need for our resins. UV LED sources can be acquired for decent prizes too. Use those in a chamber only, as harsh UV will burn eyes and skin!

@Ulf, while the sun is at a lower angle in your northern latitude, it's just as easy to get a sunburn on a cloudy day as it is on a cloudless day. Usually easier because people don't think about it, so they don't apply sunscreen. All that to say that even on a cloudy day, there's probably more than enough UV reaching Earth to cure the resin in your IPA.


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Brittle resin prints
I do not have a clear understanding of what causes resin prints to become brittle. Firstly, it appears excessive cold (in the 40s or even 30s, I am in New England) may be a factor. What else can cause brittleness in resin prints? Is there a difference between resin types?

I consider 30 or 40 unlivable Cold. Some gasses are fluid at that temperatue. But then again, Water freezes at 273.15 and boils at 373.15 Kelvin. Please use SI units!

Many printing resins are inherently brittle.
Brittle is a property of the material - so of the used printing resin.
Look at the first seconds of this video - Punished Props Academy drops an SLA/DLP printed dagger on the ground from about 1 meter and it shatters, despite having been carefully post cured and washed and everything. To mitigate that trouble they did a cast of the item with a different resin.
However, the exact brittle behavior of the print is inherently linked to the exact formulation and thus the exact brand and type of resin used.
Some are less brittle than others - and outright flexible.
You might need to test around, but there are flexible resins. This german essay contains pictures and even a video of a super flexible printing resin. Just an example: One such rubbery resin is Formlabs Flexible 80A, and Matterhackers has a range of different flexible resins. Google does show other brands too by googling "SLA Resin Flexible"

I am not affiliated with Formlabs, Matterhackers, or Techstage.de

disclaimer: I own a company manufacturing 3D printing resins, and all links lead to my products :)
Key reason - resin formula
First of all, it really depends on the composition of your resin. Some of them are more brittle than others. Usually cheaper resins are more brittle.
What causes properties to change?
That being said, some tougher resins even with some flexibility once printed can still become brittle over time. That could happen due to:

Continued exposure to UV light. It continues to cure your model and it loses its flexibility. The same goes to over-curing of your prints. If you print with longer exposure time settings than needed it will produce stiffer prints with less flexibility.
Arid environment. If the air in your environment is dry, some resins can become more brittle.
Cold environment. Heat makes plastics more flexible.

What can you do?
Best way to protect your models from getting brittle - covering them with paint or other UV resistant coating.
You can also choose resins that don't become brittle over time and is less sensitive to above mentioned causes. For example our TGM-7 resin:

Thanks for the disclosure of your affiliation - and hi and welcome to SE.3DP.

source: Stack Exchange

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

sort: votes


text:
Is it an issue when X-axis rods are able to slide in their mounting bracket?
While disassembling my printer, I found that the X-axis rods were able to be slide back and forth within their mounting bracket. This seems like it could lead to this axis shifting from vibration alone.
But, it might not matter, I think, because the extruder carriage is tensioned by a belt and it simply uses the rails as a guide to slide across. Even if the rods were to move, it wouldn't take the carriage along with it.
Will the X-axis rods sliding in their mounting bracket have an affect in print quality?
Here is a video:

If the x-axis rods only move in the x axis then there’s no problem, but if they aren’t firmly secured in the other axes then there could be issues.  If they’re able to move then presumably they aren’t secured that well.  Given the relatively small forces involved in 3D printing though, you may well be fine.

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


text:
How is my Prusa Mini damaging its X axis belt?
I just received my new Prusa Mini a few weeks ago and at first it was great. But very soon a afterwards I started having small issues creep into my prints such as shapes becoming elongated, ridges on what should be a smooth surface, and skipped steps along the X axis.
Eventually the entire head carriage started making a thunking sound as it slid across the X axis. This was from the belt, having lost some of its teeth, slipping across the motor.
Here is a photo of the damage to the belt:

Prusa service was excellent and with a photo and my order number they shipped out a replacement immediately.
Swapping in the new belt fixed everything and I thought my problems were behind me. But within a day or two of printing I started noticing problems with my prints. Upon inspection, I found that my belt was again damaged:

I've tightened belts before on my other printer and have never seen anything like this.
I did notice that the belt provided by Prusa is thinner than the one on my other printer. But the Prusa belt seems to be of a higher quality with some kind of fiber blended into it:

The obvious answer is that I've overtightened the belt. But I've tightened belts before and never had this happen.
Interestingly, both belts failed at the exact same location. The position where the damage would be at the X axis motor puts the extruder roughly centered on the build plate.

Over-tightening would be my first guess, second hunch, does the carriage run freely when moving it left to right without the belt? Does it catch on something. Note that there are many types of belts, you not necessarily need to buy from Prusa directly, a local supplier might be faster. You could try steel core, these are the strongest, but these do not last long when you tighten them too much and have small pulleys (I have had excellent experience with these on a cheap printer though).

Given that the failure is at one place, I wonder if there's something wrong with the geometry of the belt path. Does the belt appear to change its angle or tension as you move the carriage all the way to the left and right?

Looks like that the printhead snags on something whenever it moves back, most likely cabeling, whenever the head is with that stretched position just behind the roller.

I followed up with Prusa on this recently (a few months later) and they confirmed that there were issues with some belts but that this has been fixed in production.
To provide a better guarantee of quality, I opted to replace both the X and Y axis with genuine GATES 2GT PowerGrip GT3 belts. This has fixed the problem for me.


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SKR E3 mini Ender 5 Enclosure cooling system
I was hoping I could find some help as I am not that familiar with Marlin. I currently have an Ender 5 and I am in the process of replacing the stock board.
So here’s what I am trying to do: I have two small 12 V fans that I want to be powered on when the enclosure is above a temperature that I set using the Ender 5 interface. Basically, both fans get powered on until the temp is below (maybe a few degrees) the target temp. The temperature would be monitored by a thermistor.
I prefer this over using a separate Arduino as I find the Arduino adds bulk and lots of unnecessary wires etc.
I really would appreciate any help on this, or anyone telling me that this idea is impossible with the selected board. If it is possible, a detailed list, or edited code -- whichever is easier would be really appreciated.

That is strange, if I understand correctly, the fans need to go on when the temperature in the enclosure drops under a value, if you have a heated bed, that is never going to happen! Unless the print is finished and everything cools down. Marlin has default support for the opposite, the fans will go on when the temperature crosses/increases a setpoint temperature to cool the enclosure. Please explain what the purpose is of your question.

Sorry for the misunderstanding, I do mean for the fans to go on when the temperature increases beyond a point. For example, if I am printing in PLA I would want to keep the temperature relatively low, however, with ABS I doubt the fans need to be on at all.

As well, you said that there was default support for this. My main worry is that the pinouts that I have on the board may not work, as they are not meant for fan outputs. I know that may seem weird, but I do not fully understand the amount of voltage or current that is drawn through the pinout.

A pin connected to the processing unit cannot provide the current that schedules a fan or a heater, the idea is that you let a MOSFET switch the power circuit.

Oh ok, that's interesting, I will definitely look into it. Also, could I use any pinout for the thermistor, as long as I specify it in Marlin? and then a separate pinout that will connect to the MOSFET switch?


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Is 3D printing suitable for repairing a refrigerator shelf glide rail?
The plastic glide rail on which my refrigerator vegetable drawer (bin) traveled recently broke.
The rail was part of a large plastic shelf, which is no longer available for purchase.
I'm thinking about 3D printing a new glide rail and attaching it (somehow) to the existing shelf.
Can 3D printing be used for this task to make the repair any easier or more successful to complete than simply cutting a piece of plastic and (again, somehow) affixing it to the shelf?
Note that the glide rail needs to be somehow attached to the shelf at a 90 degree angle.  I keep using the word "somehow" because I haven't figured out how to make that magic happen yet.

Can you provide photos or reasonably accurate drawings to represent the reference to the 90° angle and other details?

@fred_dot_u Thanks for your interest, Fred.  Let me try to find a diagram, or take a photo.  A diagram will likely be better, because the part is white on white, which will be hard to discern in a 2D photo.

How was the original (broken) one attached? Was it a single injection-molded piece?

How much load do you expect to put on the shelf? Depending on geometry, I have seen parts withstanding quite tremendous forces by clever design.

@R..GitHubSTOPHELPINGICE Correct, the original was a single injection-molded piece.

@Trish The drawer (bin) can probably hold 4-5kg (9-11 lbs) of produce.  But there is (was) a rail on both sides, dividing the load.  Plus, and I'm no expert at this, there is probably some additional (mostly lateral) forces as the drawer slides due to friction and the shifting of the load to the front of the rail as the drawer is extended forward.

A photo works wonders to help. Best with a measurement stick

@Trish Your idea of including a measurement stick is wonderful. It might take me a little time to be able to get a photo (long story), but I'm hoping to post a diagram or photo (or both) while you kind people are still interested in helping!

Having a reference in the photo helps usually a lot to guesstimate what other items are in size - just tell us if it is millimeters or inch ;)

Can 3D printing be used for this task to make the repair any easier or more successful to complete than simply cutting a piece of plastic and (again, somehow) affixing it to the shelf?

Yes. 3D printed parts can be plenty strong enough to handle the kind of load you're considering. You'll need to create a 3D model of the part you want it a CAD program, which is something that takes some practice if you don't already know how to do it, so it may or may not be easier for you than milling the from a plastic blank.
One advantage that 3D printing brings with it is the ability to iterate rapidly on your design: you can model and print the part that you think will work, try it out, adjust your model to incorporate what you learn from the first try, and print new versions until you get it just right. If the existing shelf is broken in some irregular way, for example, you can design a new part that mates tightly with the broken edge of the part you have.

The rail was part of a large plastic shelf, which is no longer available for purchase.

Perhaps you've already looked, but there are a great many parts suppliers online. If you have the part number, be sure to look beyond just what the manufacturer can supply -- it's very likely that someone out there has the part you need.

Thanks for your helpful answer Caleb.  I've been searching for the part from many suppliers, but so far, nothing.  Another challenge with such a large part is shipping expense.

This is one of those tricky problems where the form of the repair and the materials that you need have to go hand in hand - you need a way to fix the new rail to the shelf and you need the repair to be strong enough to do it’s job.  Perhaps consider screwing the rail to the shelf - cyanoacrylate adhesive is good for 3D prints but doesn’t like low temperatures.  Once you know how you’re going to fix the rail, the design requirements will be clearer.


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What's the best way to connect pieces of a large print after printing?
I have a number of fairly large printed pieces.  The parts, when assembled, form a very large sword.  (The model is this: https://www.thingiverse.com/thing:4178060, and is not mine.)  It is about 7' from tip to pommel, and individual pieces are fairly large.  The pieces are already printed, so advice to modify the model geometry to add reinforcements at this point is moot.
I have printed the pieces in PLA.  I'm not asking for glue recommendations, necessarily, but rather something that could help with adhesion in addition to the glue. I'm concerned that after gluing them together, they won't support their own weight very well. I'm not worried about swinging it, just holding it and hanging it on a wall.
If I was very clever, I would have modified the files to add a through-hole that I would've put a pipe through or something, but I didn't think that far ahead.  I could drill holes in the printed pieces, but I don't have a good way to make sure they line up.
So, what is the best way to add some kind of support to help keep the parts from falling apart? Is there some trick I could use to figure out how to line up drill holes?

Is the sword for static display or does it need to survive being carried, or does it need impact-resistance ?

@Criggie Thankfully, I plan on just displaying it - mounted on the wall, most likely.

Superglue - aka Cyanoacrylate can do the job quite well if given help.
It depends on two flat and clean surfaces.  If your printer has any lifting in corners, glue won't save you.  The two parts have to be flat as possible, which may mean sanding with a clean sheet of 120 grit glued to a backing board.   Any coarser and it will rip strands out; too fine and it will take forever plus your released plastic micro-particles get smaller.
Also, toothing the plastic print is critical if you're gluing the bed-face to something else.  The first layer tends to have an almost glossy surface, and this is hard for the glue to adhere to.
If you can, add "gussets" across the join line, to help give the glue more surface area to stick to.
Avoid using "kicker" because it gives a weaker bond, though it sets faster.

Other solvents can help too, but they depend on the plastic you've printed in.

In your specific case, the handle looks like a weak point.  I'd reinforce across the layer lines by gluing thin metal strips to the handle lengthwise, then whipping the whole thing with jute twine and knotting the ends.  Then add more glue to the twine which will soak it in and set hard.   Hide all that using thin leather or leather-looking grips.  Bicycle handlebar tape might be a good source and comes in many colours.   I still worry about the handle-crosspiece point - perhaps be creative, or don't swing sword into things at all.

The handle is certainly a weak point - the glue surfaces there are small,  especially relative to the rest of the blade, with enormous flat sections for gluing.  Your suggestion to reinforce the handle is a good one - perhaps I could even reinforce the full length of the blade with a thin metal strip, and hide it either at the back, (as it's a display piece) or underneath some modeling compound.

I'm going to give you the check for the simple reason that I hadn't thought of post-glue-up reinforcing, and I think that'll be the best option for what I have already printed.  Thanks for the idea!

Previous answer assuming not yet printed:
If you want to drill holes, print smaller guide holes to guide the drill bit.  The best glue depends on the material.  Printing structures like dovetails makes the connection less dependent on the strength of the glue.
Answer with the parts already printed:
The best way to align drilled holes is probably to glue the pieces together first, then drill the holes.  Otherwise, you need a method to clamp the pieces together or do precision drilling.

Sorry, I'll clarify the question - the pieces are already printed, and the model is the one linked - it has no dovetails, pilot holes, or other helpful geometry.  I'm not concerned about what kind of glue to use - I can do some testing for strength if necessary.  I'm looking primarily for a way to add extra reinforcements post-printing, if possible.

A stronger joint than glue can be had by welding, albeit uglier and best used in hidden areas. One way to weld is with friction, using a Dremel to spin a piece of filament so fast it heats up and melts with the two plastic pieces you are joining. You tack the pieces together with a couple spot welds, then move along the joint slowly, melting a bead of plastic that is melted into both sides. Like metal welding, penetration is key to strength. You need a straight piece of filament (heat gun works, and rolling it on a flat surface while it is soft), and 3mm is a better size than 1.75mm, if available. It also helps if the joint is a little “V” shaped, so you melt plastic in the crack between the two pieces. Search “filament friction welding” for articles.
You can also weld with some filament and a chisel tip soldering iron with variable temperature (lower the temperature to a little above the filament’s printing temp). Melt the filament into the crack between the parts. Do something to get rid of the fumes if using ABS, etc.
Both work, friction welding might get more penetration into the parts being joined, thus a stronger joint, but they are both a sturdy way to do a butt joint between two printed parts, that would be weak if glued.
The friction welding can also be used to “rivet” overlapping parts, if you dive in and melt the spinning rod through the two parts, then stop the motor and hold it in place while it cools, then snip the end of the rivet off flush.


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Is this the correct motherboard for my Creality CR-10S Pro V2?
When trying to solve the issue described in this post I followed the advice in the accepted answer and I found that the timing pulley holes for the Y axis (to "secure" the pulley to the motor shaft) were only half drilled (!!!). I suppose that everything worked fine (even without blind screws) for the first month (probably because the belt was extremely tight) but just a bit of wearing and it started to slip.
While I already replaced the pulley I also contacted the Creality technical support to obtain (at lest! funny...) a reassurance that it didn't possibly stressed the belt or the bearing balls. My experience with their technical support has been horrible and I am still waiting (after weeks) my answer (probably it's easier for them to try to ignore their sloppy assembly and QA) but they sent me a procedure to follow to "debug" any issue with my printer.
One of the pictures in that procedure is this:

To my surprise this is the motherboard I have:

Now I am puzzled. Which one is the correct motherboard for the Creality CR-10S Pro V2 (not the old version but the newer V2)?
Is this just [another] sloppy mistake from the technical support or I do have the wrong motherboard? Differences with V1 are not many then I suppose it could even work with the old one...

Your appears to be the standard v2.4 board, which is correct for the Pro printers.
The picture they send you is from a board for the normal CR-10 models (and Ender series), which do not feature the evil 30-pin connector of the Pro.

@towe thank you! Could you please post it as an answer? That pretty much answers my question!!!

Done. As for your original issue, those little potentiometers can be found on your board as well, and should work similarly to how they described it in your mail. The "lower left" drivers in your picture should be responsible for the Y axis, and the potentiometer can be used to adjust the steppers current / power. Since your pulley was identified as the main issue, I however would not bother adjusting that if you don't encounter different issues.

@towe yes, I just followed the labels on the cables and the values were what they said so I didn't need to change anything. Real issue seemed to be the timing pulley and I've already replaced that (slightly disappointed by the tech support but that's another story...maybe I just expect too much from a product of this price)

You'll get used to that level of "tech support". Except to identify and fix the issues yourself (or with the help of the community). Manufacturer support is mostly for getting the occasional free replacement part if they messed something up.

I had that impression. Sic. What I really dislike about it is that they're using the Community as free labour. While an active and competent community could help, I believe that it should complement - not replace - the service we paid for (which could be, at very least, a decent and comprehensive official documentation!)

Guess that's a shift in expectations everybody will go through. Unlike with any other customer product, I realized you're pretty much buying the hardware, and the hardware alone. No software (because it's open source anyway), no real support. Some manufacturers do "give back" more than they "take" though, Prusa and BIQU come to mind. Others mostly "take" (Creality, Tronxy, Sunlu)

I am starting to understand that. In future I will surely support more "balanced" manufacturers. for now I'll need to stick with what I have and keep vampirising the Community for help (with the hope to be able to help back, sooner or later).

The board that's installed in your machine appears to be the Creality v2.4 / v2.4.1 board, which is the correct board for your printer.
It is distinguishable by the 30-pin ribbon connector, which is used to connect to the rest of the printer.
The board in the tech support pictures is the v2.5.2 "silent board", designed for printers such as the non-Pro CR-10 series. It features two 10-pin connectors for the LCD screen.
It also uses individual connectors for all functions, so, contrary to the "Pro" boards, is also easily swappable with aftermarket boards.
A third type of board (e.g. v1.1.5) exists, mostly for the Ender 3 series of printers, which features only one 10-pin connector for the display.


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OpenSCAD not rendering polyhedron
I'm trying to subtract a polyhedron from a cube, but it is not working (the cube remains solid). However, I can see the cut-out poly in preview mode (but not after a full render).
Preview -- poly cutout shows on the top (and bottom).

Rendered -- poly cutout not visible.

Poly Exploded -- pulled the poly to the right to show its shape.

Code
size = 30;
wall = 3;
wall_x2 = wall * 2;
nubGap = .125;
nubHeight = 8;
nubOffset = wall + nubGap;
xCutoutSize = size - wall_x2;
yCutoutSize = size - wall_x2;
cutoutLowerY = nubHeight + nubGap;
cutoutUpperOffset = nubOffset + wall;

difference() {
    cube([size, size, size]);

    translate([wall, wall, 0]) {
        polyhedron(
            points = [
                [0, 0, -10],
                [xCutoutSize, 0, -10],
                [xCutoutSize, yCutoutSize, -10],
                [0, yCutoutSize, -10],

                [0, 0, cutoutLowerY],
                [xCutoutSize, 0, cutoutLowerY],
                [xCutoutSize, yCutoutSize, cutoutLowerY],
                [0, yCutoutSize, cutoutLowerY],

                [cutoutUpperOffset, cutoutUpperOffset, size],
                [xCutoutSize - cutoutUpperOffset, cutoutUpperOffset, size],
                [xCutoutSize - cutoutUpperOffset, yCutoutSize - cutoutUpperOffset, size],
                [cutoutUpperOffset, yCutoutSize - cutoutUpperOffset, size]
            ],
            faces = [
                [0, 1, 2], [2, 3, 0],     // bottom

                [0, 1, 4], [1, 4, 5],     // side A
                [1, 2, 5], [2, 5, 6],     // side B
                [2, 3, 6], [3, 6, 7],     // side C
                [3, 0, 7], [0, 7, 4],     // side D

                [4, 5,  8], [5,   8,  9], // slope A
                [5, 6,  9], [6,   9, 10], // slope B
                [6, 7, 10], [7,  10, 11], // slope C
                [7, 4, 11], [4,  11,  8], // slope D

                [8, 9, 10], [10, 11,  8]  // top
            ]
        );
    };
};

Usually when there's an overlap in two objects during a difference action, F6 render will resolve the problem. There's something more than that involved here, as reducing the height of the cube creates a non-manifold object from the difference. user R..'s answer has merit but is not going to solve the problem.
Isolating the cube from the code and exporting the result as an STL allows me to determine that the faces are generated in a manner preventing a proper difference action:

This image from meshmixer shows the faces have inverted normals. The order of the points are critical when describing a polyhedron. From the wiki page for OpenSCAD:

It is arbitrary which point you start with, but all faces must have
points ordered in the same direction . OpenSCAD prefers clockwise when
looking at each face from outside inward. The back is viewed from the
back, the bottom from the bottom, etc. Another way to remember this
ordering requirement is to use the right-hand rule. Using your
right-hand, stick your thumb up and curl your fingers as if giving the
thumbs-up sign, point your thumb into the face, and order the points
in the direction your fingers curl.

EDIT: I reversed some of the points, haphazardly and luckily picked the correct ones:
        faces = [
            [0, 1, 2], [2, 3, 0],     // bottom

            [4, 1, 0], [1, 4, 5],     // side A
            [5, 2, 1], [2, 5, 6],     // side B
            [6, 3, 2], [3, 6, 7],     // side C
            [7, 0, 3], [0, 7, 4],     // side D

            [8, 5, 4], [5,   8,  9], // slope A
            [9, 6, 5], [6,   9, 10], // slope B
            [10, 7, 6], [7,  10, 11], // slope C
            [11, 4, 7], [4,  11,  8], // slope D

            [10, 9, 8], [8, 11, 10]  // top

Yes, OpenSCAD requires consistent normals, and from my experience actually requires (not just prefers) them pointing inwards if you want CSG functionality to all work right.

I wasn't sure about the "requires versus prefers... pointing inwards" reference, but it's "prefers clockwise" according to the wiki.

Thanks. I had just reordered the points so they were clockwise but had a similar but different issue. I guess I don't understand why (for Side A) [4, 1, 0] works but [0, 4, 1] does not (as applied to all other faces) -- they are both clockwise looking at the face, but starting from the "top" is perhaps the difference?

If the polyhedron surface and top surface of the cube are exactly coplanar, which they seem to be, it won't work; OpenSCAD operates numerically rather than analytically and which is "inside" or "outside" the other is subject to numerical instability. Whenever using differences you need to make the object being subtracted extend by at least some small epsilon outside the surfact of the object you're subtracting from.

I did extend the bottom of the poly down through the bottom of the cube and got the same results. I'll try that again, though.


text:
Ender 5 Pro bent/curved print on base
Ender 5 Pro prints are very uneven on base of the model.
In this example I printed an SD card dummy but it is not even flat.
Having a glass bed it is super strange to see this kind of behaviour.
Here are parameters in Cura.
M92 X80.00 Y80.00 Z800.00 E94.5 ;Setup step mm
M201 X500.00 Y500.00 Z100.00 E5000.00 ;Setup machine max acceleration
M203 X500.00 Y500.00 Z10.00 E50.00 ;Setup machine max feedrate
M204 P500.00 R1000.00 T500.00 ;Setup Print/Retract/Travel acceleration
M205 X8.00 Y8.00 Z0.40 E5.00 ;Setup Jerk

Thanks in advance, I tried quite a few calibrations but nothing helped so far.

Hi, welcome to 3DPrinting.SE! This is a classic example of not enough adhesion. Tune bed temperature, use a brim or add an adhesive layer like glue stick or hair spray or a dedicated print adhesion spray.

Thanks for your reply, Oscar - indeed, I used a glue stick and the issue disappeared. Cheers!

This is a classic example of not enough adhesion. Tune bed temperature (usually hotter), use a brim or add an adhesive layer like glue stick or hair spray or a dedicated print adhesion spray.
The question "Warping of bottom of print" has an accepted answer that explains in detail how and why this occurs.

This. However most often ppl try to solve it by smashing tighter against the build platform, which causes elephant foot and other nasty issues. In my experience hotter bed temp and brim are the right fixes, and brim works even with a brim gap of 0.25-0.3 mm which avoids marring of the part.

Cheers, will also try to increase the bed temperature. Currently set to 50 degrees celsius


text:
What material should I upgrade the teflon tube to?
I'd like to print PET on an Ender 3 v2, but I see that some people recommend upgrading the hotend because it will melt the teflon filament feeder tube. I'm not sure if the hotend will even get hot enough to use PET, even though it's listed in the specs for the printer.  I didn't know Teflon could melt, if that's the case, should I get rid of my teflon cooking pans?

What is the max temp range for a stock Ender 3 V2?
What material tube should I upgrade to?
What are the benefits of an all metal hotend as far as hotter temps?  Why is that the recommended solution for PETG printing?

The Ender 3 (original, pro, or v2) does not need any modifications/upgrades to print PETG. Temperatures of 230-235 °C are sufficient for PETG and well under the 250 °C that's not recommended to be exceeded on a machine with PTFE lining all the way to the hotend. PTFE doesn't melt above these temperatures, but it does start to break down and release chemicals that can be harmful. Note that teflon pans achieve temperatures comparable to or exceeding what you'd print PETG at all the time while cooking, and especially if you burn food. The smoke point of peanut oil is roughly the same as the temperature you print PETG at.
If you did want to change it (I wouldn't recommend this) there is no different tube you can "upgrade" to. Instead, users who want to be able to print higher temperatures switch to an "all metal" hotend, which means the tube doesn't extend through the heatbreak to the hotend, but instead stops in the cold part, with a metal passageway for the rest of the filament's path to the hotend/nozzle. You still use the same PTFE before that, though. All-metal hotends are not necessarily an upgrade; they're a tradeoff. The PTFE tube all the way through is a highly desirable feature because it has very low friction and no ridge/boundary between materials for semi-molten filament to get caught on when retracting and unretracting.

Capricorn claim their bowden tube can withstand 300 °C.


text:
I can't figure out how to name this problem or solve it
(Ender 3 Pro with Bigtreetech Board and Touchscreen, BlTouch)
Hello everybody,
I want to print something for my family but the hotend gets clogged every time in the same part of the print. I tried:

Different Nozzles
Different Filaments
I cleaned every Part
The E-Steps are set right
The retraction Setting didn't make a difference
The Extruder Position is perfect
I tried different speeds
Everything else you find on Google with a clogged hot end.

The most odd thing about this is that the problem occurs at the same place every time.
On Flat surfaces are some anomalies, that wasn't there when I had the normal clogged nozzle problems (from: retraction settings, dirty Printer, e-steps false). I think it has something to do with the anomalies.
Another thing I don't get behind are missing layers after the layer change,
even when I don't use retraction at all.
In The Picture from the side you see the Support with the Layer change problem.
After around about Layer 40  there is one Layer missing and the next Layers are not connected anymore.
From the top you see the Surface anomaly I don't know how to describe.
It would be helpful to know what I did wrong. I am sure I did Everything against a clogged Nozzel but I can be Wrong so tips in this direction are Helpful too.
I am quite new to 3D Printing(2 Months) I had the usual clogged Nozzel Problem Solved and It Worked Perfectly. I Tried to Fix It with the same Solutions and Nothing Helped, so I think it is a different problem.
Sry for my bad English I am from Germany.

I have an Ender 3 Pro with Bigtreetech Board, Touchscreen and BlTouch which I use together with [insert slicer here]. I print in [PLA/ABS/PETG/Whatever Material] at [Extruder temperature] °C. The print bed is set to [Bed Temperature] °C. I use a print cooling fan at [whatever] %. The layer height I set to 0.[x] mm, the line width [line width/extrusion width] from the 0.[x] mm nozzle. The Printing Speed is set to [x] mm/s for walls and [x] mm/s for infill. My retraction is [off / [X] mm at [x] mm/s].

that loooks like terrible layer adhesion, possibly caused by underextrusion or wrong temperature

I gonne test with a new Temp and adjust the E Steps again

So the printer stopped extruding entirely after this kind of under-extrusion?If it is then it looks like a heatcreep to me.Happened on my ender3pro before.

Ill look it Up today

Conclusion
So I found my mistake: It was the E-Steps I did wrong it over extruded. The best E-Steps per mm are 92 for me. The mistake took place because I took my E-step number from a Video Tutorial about my dual extruder. I found the optimal number by testing out; the formula I got for the E-Steps was in the Video and I think I  used it wrong, I'll watch the Video again and look at what I did wrong and I'll write a comment about it. I will test more today to get it perfect but @Trish was right.
Thank you to everybody for their Time.

How the problem was diagnosed:
Did I have a bad Temperature?
First, I tested all temperatures in the range of 190 to 210 °C, and the best looking is 200-205 °C. After that, I tried a different height for my print head which just resulted in the model not sticking to the bed. So I could rule out bad layer height.
This was made at 200 °C, The problematic areas are at the corners and on Flat Surfaces parallel to the heat bed:

Is the Cura profile the culprit?
I made a new printer Profile to find out if I broke it in the settings. I got the same results.
So I tried every Setting in Cura that could have something to do with that, the only thing that helped a little was using 50% Top Surface Flow:

While testing, I saw that the corners are really bad. I think it's because of the print head acceleration. So, I went back and tuned more...
E-Step Configuration Issue Identified:
Finally, I revisited the video I saw originally and figured out, it might be the E-steps per mm. I went through trial and error to come to 92 and realized, I had mistakenly inserted a number for a different extruder setup.

I'm an Ender 3 Pro user and I've been through almost every problem this machine has.

If you are on original hotend and Bowden style extruder, then first try the hot end PTFE fix

What the picture may show is a temperature too low, especially on these bad layers. Raise the temperature like you have tried (200 °C is good).

To avoid prints being knocked off the bed, try brim (it's in bed-adhesion in Cura), most people don't use raft anymore. What brim does is to add addition loops on the first layer of your prints and make it sticks as good as possible.

No raft, add brim. Then disable Z-hop, enable combing in Cura.

These steps should be able to mitigate the problem.

This does not look like a bed adhesion problem but something wrong with extrusion. Temperature may mitigate it, but if your printer is working properly, the entire range 180-220 or more should be "usable" with PLA (i.e. not having this kind of catastraphic print failure) just subject to different strength, cooling/warping, etc. properties.

I use the older 2018 model of the Ender3, and so far I have had only to replace some consumables and my extruder for an aluminium one, some nozzles, and one time a fresh Bowden, and I am golden.
To me, I see 2 problems:

You might print too cold. I print PLA at 200 °C, some brands I do print a little hotter.
You measured your extrusion rate. That is wrong. You need to calculate your steps per millimeter!

Because I don't know your printer, you need to look at how to calculate your proper steps/mm. I assume you have the Typical NEMA17 motor with a 1.8° per step (=200 Steps per rotation) and 16 Microsteps:

$d=2\times r$ diameter of the push-gear = 2*Radius
$C=d\times\pi$ Is the Circumference
$Step = 1.8°$ & $Ms=16$
$S=\frac {\frac{360°}{Step}\times Ms}C =\frac {200\times Ms}C =\frac {3200}{d\times\pi}$ Steps/mm

For a typical gear of about 10.5 to 11 mm diameter, that gives numbers between 97 and 92.5 steps/mm. Use your calculator to establish the minimum and maximum numbers first by using the top and bottom of the gear. Then you can test for the correct number in between these numbers. Depending on how soft the material is, the place for the effective gear diameter shifts: softer materials are closer to the high steps/mm number, harder ones more to the low steps/mm end.

@0scar I tried differnt Temps with a Test Cube and Differnt Speeds. Its got better but there are Still 'Anomalies' and The Printer cant print to Long. To day I will search for a Better selution. While Printing some Lines are Getting to big and thats why Flat surfaces stick out alittle. It Seems like a overlap Problem of the Lines. I dont use any overlab Procentige so Idk why therek is a Overlab. I hopefully will find out soon. But I first will ubgrade The Printer with a Camera to Show what I Mean.

@Ericsonpsy can you show a new picture? With some more info, we might help you tune your printer. I have included a template in the bottom of your pot that can help us help you! Please fill in the [blanks] with your settings!

Today I get the rest of the new Stuff for the Printer and than i Will make new Fotos

@Ericsonpsy Depending on the hardness of the filament the effective gear radius will change: with softer filaments (ABS, nylon, PETG) the teeth bite deeper and the steps/mm increase. You still need to extrude 100 mm of filament, measure the actually extruded length, and correct the steps/mm accordingly. You can also use the flowrate, which will result in the same result but it's a less clean solution.

@FarO true but you can calculate the minimum and maximum numbers and go from there.

I agree, it's important only to point out that an "a priori" (theoretical) calculation is usually not enough. I like your edit.

@FarO: IMO the cleanest solution is to set the steps/mm to the ideal for perfectly stiff filament, and set the filament diameter (especially nice if your firmware has volumentric extrusion mode) to the effective diameter as it passes through the extruder gear. That way you keep what's a material setting with material settings rather than constantly changing your machine-mechanical-property settings for each material.

@R..GitHubSTOPHELPINGICE that's also an idea, even if Slic3r and derivatives have a field for filament-specific g-code which would work well too

I noticed that on my Ender 3, if the belts aren't tight enough, I have a similar problem, but mostly when I print anything circular.


text:
Export STL from OpenSCAD command line, calling module within script?
Given a .SCAD file which contains some modules, how can I execute one of those modules from the command line?
example.scad
module One() { ... }
module Two() { ... }

render.sh
openscad -q -o one.stl --module One example.scad

Note that there is no --module option, but that is what I'm attempting to do. The workaround would be to make another .SCAD file e.g. one.scad which includes example.scad, and simply calls One(); within and render that file from the shell file. But this is not ideal.

The openscad -D option can actually include arbitrary code, not just variable definitions, so you can include a call to the module.   You can even use /dev/null on Linux or NUL on Windows as the input file and have 100 % of your code in -D statements.

Maybe showing how exporting the STL works would benefit the answer.

OpenSCAD doesn't have such an option on the command line, but the general idiom I believe you want to use is have .scad source files which are modules include invocations of the module(s) at the top-level controllable by variables you can set on the command line or GUI customizer interface. Any such invocations will be ignored if the file is used (via use directive) in another file so they don't hurt its status as a library and make it easier to preview/test. So for example you could have:
wantOne = false;
if (wantOne) One();

and then set wantOne to true from the command line.

Thanks. I think that is better than having a separate .scad just to call each module.

elaborating on the answer from @r-github-stop-helping-ice, I find the following pattern useful:
example.scad
module a() { .. }
module b() { .. }
module c() { .. }

module print(item=0) {
  if (item==1) a();
  if (item==2) b();
  if (item==3) c();
}

item = 0;
print(item);

render.sh
#!/bin/bash
for i in {1..3}; do
  openscad -D item=${i} -o item_${i}.stl example.scad
done


text:
Retuning a very delicate and tricky print after print failure
I recently leveled my bed on my Monoprice Select Mini v2 and tried printing this object with family:
Pentagonal Hexacontahedron Bracelet by mathgrrl - Thingiverse
https://www.thingiverse.com/thing:288182
The symptoms were as follows:

the print footings did not stick to the bed
during the print some of the footings looked misshapen
Eventually everything lost cohesion and looked like a mess of silly string
the insulating tape on the heating block started to come off

Immediately after the insulating tape came off we aborted the print.
Here are the steps we followed to convert, slice and print the object.

We loaded the STL file into Ultimaker Cura 4.8.0, using a preset in the wizard for the Monoprice Select Mini v2
We opened the STL for the small bracelet, chose ‘Slice’, and copied the resulting .gcode to a microSD.
We popped the SD into the printer, preheated the nozzle and extruded a small amount of PLA (we used the PLA for a demo print of a cat hours earlier and it worked great for the demo)
We went to print and chose the .gcode for the small bracelet and let it start to operate.
The heating settings for the bracelet .gcode from Cura were a bit different different than those used for the demo cat .gcode that came with the machine. Both had the nozzle heated to 190 °C. The bed heating setting for the bracelet was 5 degrees hotter than the cat at 65 °C.

Any tips are appreciated. I don’t know what happened or if it possible to print this object successfully with the Monoprice Select Mini v2.

That print is very delicate and tricky. I suggest to use: Brim & support. But the tape is a machine-manner, not one of the print

I'm replacing the tape. I'll read up on 'Brim' & 'Support'. Is this what you were talking about? Brim: https://all3dp.com/2/3d-printing-brim-when-should-you-use-it/  | Support: could not find. Send a link with docs for what you mean by 'Support'?

the tape on the printhead is usually Kepton and holds some sort of insulating pad. Fiberglass or rockwool or something similar.

The print is extremely challenging, as it has a lot of thin diameter items growing up, a lot of overhangs and a rather small surface to hold to the bed. So you need a Brim and support:
As OP found, a Brim is a setting that adds extra material in the first layer around the print to increase adhesion.
Support Structures are to give an overhang something to rest upon. Removing them can be tricky, but they make some things printable at all. Like this bracelet. You'll have to finetune your settings, best by learning with less complex models first or mimicking the settings of others that made the bracelet.
The thin vertical parts can make the print fail nevertheless - you can possibly fix some of the vertical adhesion issues by printing slower. If these parts are too thin, you might be unable to print them at all with a 0.4 mm nozzle! As a rule of thumb, it is really tricky to print pillars slimmer than 2.5 nozzle diameters and almost impossible to print them nicely under 2 nozzle diameters.
My settings
I print my PLA at 200 °C, the bed at 60 °C, but then again I don't have a glass bed.

I only print on glass, for PLA I use exactly the same temperatures. But note that temperatures may vary a little from brand to brand, also on application.


text:
Ender 5 SKR Mini E3 -- After Heating the Hot End Assembly Runs into the side of the printer
So I got the SKR mini E3 for my Ender 5 after hearing all the positive reviews.
When it arrives I plug everything in, make sure it's secure and test the axis... they all worked correctly.
I then tested auto home... everything worked.
I then tested the heating... everything worked again.
Finally, I go to do a test print-- it heats up and then homes. When it is finished heating, the hot end assembly starts moving slowly until it goes into the corner and contacts the side of the printer. Obviously, I turned it off right away.
Currently, I am uncertain whether it is a firmware issue, a board issue, or something else? If anyone could please help me solve this, that would be greatly appreciated!

It means the endstop is not working. Assuming no mechanical changes to where it's mounted, either it's not connected to the right place on the board or the firmware is not processing it correctly.

This issue is related to the way Creality has defined the origin of the printer. Usually, the origin of the printer is at the front left when facing the printer. Creality has chosen to set the origin in their default Creality configuration at the back right.
Vanilla Marlin (Ender 5 configuration) has the origin at the front left. When facing the printer this makes more sense. Do note that there are printers with the origin in the middle and in the back right location, but these are outnumbered by far in preference of the front left location.
This means that when you switch boards you need to carefully look at the settings of the endstops and the definitions of the being min or max endstops and inverting or not of the steppers.

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

Please expand the answer with the changes you made, others may benefit from it. This answer doesn't explain well enough to fix it. Thanks!


text:
CR-10 Extruder Clicking / Filament jammed in Extruder?
I have a CR-10 S5. I was very happy with the way it was printing but all of a sudden it cant get past 1 hour of printing without the filament breaking in the extruder. I have caught it in the act, it will be printing fine then the extruder will begin to click. I paused the print which lifts the hot end off the build plate. I can easily pull the filament out of the hot end and the Bowden tube, it will still click in the extruder. I release the clamp on the extruder and pull a few inches of filament through, cut it off and feed it back into the Bowden tube and hotend. Resume the print and it will continue printing fine until the extruder gear starts skipping again (maybe another 10 minutes in).
When I pull the filament out of the Bowden tube after it has jammed I notice the end of the filament closest to the hotend is still nice and round, but as it gets closer to the extruder there are teeth marks in the filament and it is also flat.

First few layers go down good - extruder doesn't start clicking until ~ 1 hour into print.
I have tried releasing the pressure on the extruder clamp - which leads to the gear slipping on the filament and wearing it away until it breaks.
I have tried with different filament (one brand new fresh from packet) - same result, I have tried drying the filament in a filament drier - same result.
I have replaced the nozzle
I have pulled the PTFE fittings from the extruder and hot end and nothing is blocked.
The Bowden tube is pushed fully into the hot end and extruder.
I have checked the extruder steps/mm and is okay.

The printer is in an enclosure and my ambient temperature is usually 30-40 °C, I'm wondering if the filament is getting heated up to the point where it is soft enough for the extruder gear to damage it?
Printing at 50 mm/s and 215 °C PLA , really lost where to go from here...

This is most probably a heat creep issue, resulting in a partial clog. You need to print PLA at a much lower temperature, e.g. 200 °C. Printing faster is also an option, as are less aggressive retraction settings.

Where would this clog be found? I have pulled everything off and cannot seem to find anything blocking up, i just pull some fresh filament into the extruder and it seems to print fine again for a while..
I have been printing at 210-215 since day 1 (But i was printing at faster speeds)  but i will try at 200.. People keep saying to print hotter when i say the extruder is clicking..

I have now tried to print at 200C, but same issue.
When it does this a can still release the spring on the extruder and push the filament through, so i don't believe it is clogging. But when i try to push the filament through from the extruder the filament seems very soft..
My extruder motor is getting very hot, i can only hold my hand on it for 1 second, i believe it is transferring this heat to the extruder gear then to the filament

If your stepper is too hot you could reduce the current by adjusting the stepper driver Vref. As long as you can touch it, the stepper is OK, most operate to a temperature of about 80 °C, Unless you have PLA mountings, that shouldn't be a problem. Also heat creep softens filament causing the clog. But, if the heat is affecting the filament by altering the shape, you should at least try to lower the temperature of the stepper to rule this variable out.

Yep i have just read about the Vref so i will do that once i get a chance,
I can touch it, but only for a couple of seconds, The Y-Axis motor is also very hot..
I have also ordered a heat gun so i can actually check some temperatures..


text:
Can closed loop steppers be used for extruders?
I am relatively new to 3D printing, but have some background in industrial equipment and test machines.
An important part of printer setup is getting the extruder mm/step rate configured correctly.
I was wondering if anybody has done any research into closed loop drive of the filament where the feedback to close the loop comes from a knurled idler on the filament.
This would mean factors such as drive slippage and different material stiffness could be automatically compensated for.
Going one step further the feedback wheel could be placed at the hotend of Bowden extruder systems negating the need to tune in retract settings for different materials as the closed loop system can just pull back however much material is required to get 1-2 mm as measured at the hot end.
I have seen there are readily available steppers with drive boards built in for closed loop control, I would imagine it would be a relatively simple task to remove the hall effect sensor from one of these boards and mount it remotely to read off a measuring wheel instead of the drive shaft.
I had a bit of a search but couldn't find anything on this topic online, is this something that has already been looked into and if it hasn't are there any significant reasons why this shouldn't work to improve performance and/or reduce manual tweaking and calibration required.

I'm wondering if thus would be useful, if an extruder skips, there could be a fundamental issue that isn't solved with monitoring the steps.

Skipping resistance is more a side benefit, as skipping comes with its own issues such as chewing into the filament. The benefits were more calibration (where different spring forces or filament hardness results in a different effective drive gear diameter).

I guess you therefore mentioned the separate knurled feedback option?

The cost of the encoder for the closed-loop is more than just turning up the power on the stepper motor. In practice, a well-tuned machine never slips.

As per before the benifit is not having to calibrate e-steps as well as having automatic compensation for Bowden tube elasticity.

https://github.com/KevinOConnor/klipper/issues/2610 a possible feedback design for the extruder is discussed

Looks interesting, I might have to play around with a custom hot end design to test it.

Closed loop steppers like S42B are becoming popular for the spatial axes because compensating for skipped steps is the correct way to recover for those axes. For example, if the nozzle knocks into a warped corner of a print and skips, the right thing to do is compensate, commanding additional steps necessary to get to the commanded location.
This is less valuable for extruder, since displacement is not necessarily the target we want to recover, but nozzle pressure. Extruder skip usually occurs when nozzle pressure exceeds the motors ability to drive the filament. Correcting for the skipped steps may result in overcompensating, attempting to drive nozzle pressure up over a longer period of time, since the problem won't clear itself as quickly as it does for the spatial axes. Compensating for skipped steps doesn't recover E errors like they do for X,Y, or Z, since skipped E steps tend to be driven by persistent problems, like low nozzle temp or hotend restrictions, where spatial errors tend to be transient, e.g. hitting a 'speed bump' on the print.
An alternative is filament flow sensors like this BTT Smart Filament Sensor. It uses a similar feedback mechanism like you suggest. It uses a driven wheel and encoder to send pulses to mainboard. When mainboard stopped getting pulses during commanded moves, it pauses print. Instead of trying to correct in a closed loop fashion, its a human-in-the-loop solution


text:
What firmware type to use for FLSUN 3D printer in PrusaSlicer setup?
I have a FLSUN printer: 3D Printer DIY Kit Auto Leveling Cube Full Metal Square Large printing size 260X260X350 with heated Bed Precision.
I plan on using PrusaSlicer as slicer (found it in Ubuntu.)
I now need to pick a Firmware Type in the setup screen. Which one should I select? I vaguely  remember it should be RepRap, but I'm not sure.

Does the printer not display the firmware name and revision when it powers up? It is probably either Repetier or Marlin.

I never turned it on. I guess it is time to do so! I will do this next week...

Most common is RepRap, as most printers use Marlin, which implements the RepRap code Style.


text:
Ender 3 Inconsistent Bad Prints
Recently, my Ender 3 printer is giving these bad quality prints as shown in the image below. Something in common in all these bad prints is that they only fail in a particular section. The print looks good on the rest of the parts. I'm having trouble on how to find people with similar problems as I don't know what type of failure this is called. I would really appreciate any suggestions on how to fix this or if anyone experienced the same issue and managed to solve this.

Hi, welcome to 3DPrinting.SE! Are your belts tight?

Looks underextruded from bad temperature to me

I agree with @Trish, very similar to an under extrusion issue I had with my Ender 3. In my particular case it was because the nozzle was clogged.

I'm with @0scar, looks like a belt is loose.


text:
How can I test that my stepper motors for functionality and compliance?
I bought a set of 5 stepper motors from Trianglelab's official Aliexpress shop.

Only one of these motors was given any kind of protective bubble wrap for shipping. The contents of the package shifted in transit and several of the motors got banged up with two of them suffering visible damage to their wire insulation.
I contacted Trianglelabs and was told to fix it myself for \$0.03 with a wire or to add some tape. This repair advice was accompanied with the weightiest assumptions of my personal expertise that I have ever received.
At this point I'm not planning to keep them if this is how the company does business; shaving pennies on shipping and telling the buyer to fix it themselves.
But all of this brought up an interesting question. How can I reliably test my stepper motors for basic functionality and measured compliance with the rated specifications?

At a minimum, you could check the resistance of the windings for open circuit/short circuit.

Can you share photos?

Trianglelab is usually a very reliable seller, just like Bigtreetech. I would not exclude them for a single issue. Have you opened an official ticket or have you written them directly? official disputes are REALLY efficient and you usually get the whole sum back. No seller wants to mess with Ali's rating system, considering how difficult is to get into Ali's webshop (I know people who wanted to but did not qualify yet).

Trianglelab accepted AliExpress's proposal of refunding 1 of the 5 motors yesterday. I had sent a revised offer to refund the two with damaged wires instead of returning the entire order for a refund (my original proposal). Trianglelab countered by pre-emptively closing the case by accepting AliExpress's better proposal. They never respond to any of my messages on their store. Today I found out that sellers (not just buyers) can accept AliExpress's resolution proposals.

For the AliExpress part, open a dispute and attach pictures to the dispute and ask for a partial, reasonable discount. It always worked for me.
As for how to test the motors themselves, it depends on what other hardware you have.
For example, you could wire the motors to your printer board, and try to issue a G6 command to that motor.
If you find issues while testing the motors, that could be evidence for an even bigger discount, or even full refund if the motor doesn't work.

I would dispute and state "wares came in unusable"

I would be far more worried about damage to the wire insulation (i.e. are they nicked/cut at all or just scuffed up?) as that could potentially lead to a short circuit situation against your frame etc.  Assuming no serious cable damage, motors can take a fair amount of mechanical abuse so I'd just put them through their paces with short (a few seconds) forward/backward movements at various speeds listening for any scraping/grinding/other unusual noises indicating any interior damage.  Assuming no issues found, then you could run them for a more extended period of time (5-10 minutes or so periodically changing direction/speed) and if that didn't reveal anything, I wouldn't worry about it.  If it helps, you're probably going to inadvertently abuse them electrically/thermally far more than the shipment did over their service life.
Unfortunately, when shipping things overseas sometimes the packaging is insufficient (somewhat surprising for Trianglelab as that's one area I generally see people give them high marks for) and bad things can happen during shipment.  I've received all sorts of mangled packages and, aside from the irritation of knowing it was probably avoidable but for the bad packaging, I usually try to be reasonable when tallying up any damage when asking for a refund (partial or otherwise).  If you really feel like a seller fell short, then your best recourse is generally to ding them on their rating if it's really warranted.  Yes, it's irritating, but it will happen from time to time.


text:
What effects does the non-carthesian coordinate system have on the Part-design process for printing with a belt printer?
Background: What's a Belt Printer's Coordinate system?
For "normal" Cartesian (Portal, Cube) or Cylindrical (Delta) coordinate printers, the same Design Consideratons are to be kept in mind. But on a Belt Printer aka Printer Mill, the conversion from cartesian design space to cartesian or cylindrical printer coordinates is not applied in the same fashion, and as such some considerations based on subsequent laying down of full levels do not apply the same: While there is a common alignment of two axis, the third axis is tilted forward and the printhead does move in the angled X'Y'-Plane. While the Belt moves only in one direction, never backwards, there is a component of negative movement in that direction by lifting the printhead...
The formula for how the new coordinate system is translated to is thus as follows $$X'=-X$$ $$Y'=\cos(\alpha)Z$$ $$Z'=Y-\sin(\alpha)Z$$ To Illustrate this: The Red-Green-Blue is the orthonormal cartesian coordinate system. and the Magenta-Yellow-Cyan is the coordinate system the printer moves in:

The most common angle for currently available designs is 45° as in the Blackbelt or the coming Creality Belt Printer (pre-production in December 2020), making the math for the slicer somewhat easier as $\sin(45°)=\cos(45°)$. As a result of all the math, there is a Cura Derivate, the BB Cura 3.6.2.
Question
What impact does this movement pattern of laying down in an angle upwards have on considerations that have to be taken in the design stage of a model for 3D printing?

Maker's Muse has a video talking a bit about this.

@R..GitHubSTOPHELPINGICE And so have others, like Joel

Seems like there hasn't been enough trial and error yet to figure things out :(

The first and most important design consideration is the overhang. Normally, when designing a part, you would make considerations based on the fact that gravity will act on the part from the "bottom" towards the top. As a result, when I am designing a part, I am always mindful of the fact that anything which protrudes outside of the intended printing base will be subject to "overhang" forces. Therefore, based on the layer height and nozzle diameter, there is a limit to the maximum overhang angle that can be serviced by the printer. Just as a side note, printers that co-extrude dissolvable supports, do not have overhang problems.

Additionally there are structural considerations with the laminations being at an angle, especially with holes that are intended to have heat-set inserts. Normally, when applying an insert the pressure is perpendicular to the layers. However, depending on where the hole is needed and how the part was printed, the inserting process could promote delamination of the layers and early part failure. It could be even worse with holes that are being threaded subsequent to printing.

Because the first few layers are going down at an angle, the layer adhesion will be unknown.

At design time, all you would need to do is keep an eye on those overhangs. I'd start all models on a plane that was at a 45degree angle. That way I can see the effect of having it being printed on its side rather than perpendicular to the bed.
"The first 3D-printed boat, 'built' by the world's largest 3D printer" was also printed with the nozzle at an angle to the bed; and that seems to have worked out well.

The design of a belt printer puts the printhead to print in layers tilted by some 45° to the XY-plane. How would this impact the design considerations?


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UBL Marlin settings to cover whole bed
This question is related to:
How to set Z-probe boundary limits in firmware when using automatic bed leveling?
I am trying to figure out how to set UBL In Marlin to cover as much bed as possible.
So My bed is size of 300x255 mm
#define NOZZLE_TO_PROBE_OFFSET { -34, -1, -2 }
My Probe can physically cover 255 mm (whole Y) and 272 mm (of X size)
Let's give it a bit of margin of the 0Y -> 3 mm and from 0X -3 mm
So idea is to cover X from 3 mm to 269 mm and Y from 3 mm -> 252 mm
How should I set
#define PROBING_MARGIN
and
#define MESH_INSET
so it covers my bed and probes 100 points ?
I tried different options, most of the time it stops at 57/100 and printer HALTs.
Only setting I got it working with was:
#define PROBING_MARGIN 30
#define MESH_INSET 50
But that does not cover whole bed. I am struggling to understand how it's calculated.
Other settings I found was commented as below.
#if PROBE_SELECTED && !IS_KINEMATIC
  // #define PROBING_MARGIN_LEFT PROBING_MARGIN
  // #define PROBING_MARGIN_RIGHT PROBING_MARGIN
  // #define PROBING_MARGIN_FRONT PROBING_MARGIN
  // #define PROBING_MARGIN_BACK PROBING_MARGIN
#endif

Any suggestions ?

PROBING_MARGIN and MESH_INSET make the effective probing area smaller, so if you want to have more area, you should reduce the value of these constants.
As of Marlin 2.x, the probing area isn't defined directly by the firmware configuration settings, but calculated, based on the probe offset settings. The constants you mention are reducing the probing area to keep the carriage/nozzle on the build surface.
If you have enough space on your printer to accommodate probing the whole bed, you could minimize the marging and define edges:
#if PROBE_SELECTED && !IS_KINEMATIC
  #define PROBING_MARGIN_LEFT PROBING_MARGIN
  #define PROBING_MARGIN_RIGHT PROBING_MARGIN
  #define PROBING_MARGIN_FRONT PROBING_MARGIN
  #define PROBING_MARGIN_BACK PROBING_MARGIN
#endif

Thank you for the response, I did get to that setting, however it doesn't seem to work as I thought it would, somehow I've managed to cover most of the bed, but it still doesn't finish 100 points but stops at 91, however at least mesh is valid after that.
What's the case, when it calculates probing points ( 100 ) and some of them are outside allowed area, because that's what seems to happen

Could be you don't have enough memory to store the points?

As far as I understand, this is how the limits are calculated:

The probing size is first calculated from X_MAX_POS and Y_MAX_POS and your NOZZLE_TO_PROBE_OFFSET values. If you changed the extruder or part cooling system or added a BLTouch you will have to update these.
This calculated area is reduced by MESH_INSET if you want to make the probing area smaller. I don't really know why you'd do this so I always just set it to 0, and also it seems totally redundant with PROBING_MARGIN. I don't know if they are calculated any differently, it would be great if the comments in Marlin were a bit clearer here
This area is further reduced by the PROBING_MARGIN for situations like if you have bed clips around the edges, or if you're using a contactless probe which can get bad values near the edges.

So basically, if you're using a contact probe like BLTouch and you don't have any clips or obstructions around the edges, you can just set both MESH_INSET and PROBING_MARGIN to 0 then provided your X and Y axis max positions have enough extra room compared to the nozzle to probe offsets, you should be able to probe all points without issue.


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Clear coating resin 3D prints
I'm looking to put a UV-blocking clear coating on some of my resin 3D prints.
I've tried krylon UV-Resistant Clear Coating but it seemed to react with my print making it softer and easy to break. I'm trying to coat a thin Lithophane so I would rather not make it any softer.
Are there any better options for a UV-blocking clear coat for resin 3D prints?
Printer used: AnyCube Photon (dlp)
Resin used for Print: ELEGOO ABS-Like 3D Printer Rapid Resin
Lithophane maker: lithophanemaker

try clear nail polish, maybe UV curing polish at that.

nail polish seems like a good option for clear coating but is it UV blocking? I feel like UV curing polish would not necessarily mean be UV blocking.

I'd go for the easy option of using a composite setup: Acrylic lacquers themselves are very low reactive and can serve as a foundation before the UV clear coating is applied. The acrylic lacquer itself doesn't change coloration if exposed to sunlight, but the light can still pass and discolor the lithophane.
Your Krylon clearcoat technically is an acrylic paint, but to be used from a rattlecan, other chemicals are added - a whole lot as the MSDS tells us. The list of chemicals besides the paint in that can are Acetone, n-Butyl Acetate, Propane, Butane, Xylene, Ethyl 3-Ethoxypropionate, Cyclohexane, Ethylbenzene,
Bis(pentamethyl-4-piperidyl)sebacate. Three simple chemicals I put in italics - they are very good solvents that easily react with the resin print. Propane and Butane create the pressure in the rattle can, the other four chemicals make up the actual lacquer. I have observed the mix of Acetone, Cyclohexane, and Ethylbentene (with possibly others) softening PLA, so it is totally possible that they react unfavorably with your resin print. As a result, I suggest using a brush or roller to apply acrylic paint from a can (not spraycan!)


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Flow + Line Width = over / under extrusion, how does that work?
I am just trying to deeply understand relations between those parameters. I am not a noobie, but just trying to be more smart with a printer, instead of changing parameters randomly to see effects on the print.
So Let's Assume Bed is leveled perfectly and all Motor steps are calibrated correctly (X,Y,Z,E)
I do understand some of the correlations e.g.:

When Flow is too low, on first layer you have to lower Z-Offset to get nice squish, but next layer will be under extruded, because Z-Offset does not apply on any layer except 1st.

When your flow is too high, you have to bring Z-Offset higher, to get first layer perfect, but then next layers will be over extruded and looks squished too much.

Now, I have calibrated flow, with method of printing shallow cube with 2 walls (perimeters). I've set all line widths to be 0.4 (like my nozzle), so on the measurements I expect wall to be 0.8 (2x0.4), some tutorials says I should aim for 0.82, but for now I left it at 0.8 which was pretty much spot on.
Leaving line width's set to 0.4 for all lines and layers, and line height to 0.2 on all layers, I started printing, on the fly I adjusted Z-Offset to get that first layer right. But on every other layer, I had too much squish (over extrusion).
And that does not fit the things I though I understand. Because now if I lower flow, flow calibration will come wrong.
I also know that by default in most slicers, layer height and line width are not set to same values for all layers.
Of Course I could just fiddle around, keep changing those settings and probably I would finally get what I want, but I want to understand what to change and why, so rather than telling me what I am doing wrong, I would like to know how it should work, I am guessing there is How it should work in ideal world, and how it works with budget printers. But I really really want to understand that part of the printing, and maybe there is other complications I am missing in here.

Level to 0.0mm, set extrusion width to 110-120% of your nozzle diameter.
Calibrate flow like you did (2x walls, aim for exactly that) and compensate the rest with first layer flow or Z offset.

why extrusion width should be set to 110-120% of the nozzle ? I've seen that before but why is that ?

You're pushing hot plastic through a hole with a 0.4 mm diameter. It's going to expand a bit upon leaving it - you'll never know exactly where. Extrusion width is usually set a bit larger than the nozzle diameter to catch that uncertainty.
It's also why you can't reeeaally print with extrusion widths < nozzle diameter: How do you tell where it's going to go?

I get you, makes sense. I think I need to understand where are those imperfections in the printer, so it can be all 1:1. So, following what you said, I should set width to 110 of my nozzle, and when doing calibration should I still aim to 0.8mm (2x0.4 of the nozzle) or aim for that extra 110% on the width ?

You'd set your extrusion width to e.g. 0.44, and calibrate so that your two walls are 0.88 thick.

Cool, after that, should line width (extrusion width) should be same for all layers, or maybe there is some pattern to follow, similar to layer height where first layer should be thicker for adhesion etc? Currently I have it set up same for everything.
Or like you said previously, change flow for first layer and leave it default for the rest ?

Thicker extrusions on the bottom layer might be beneficial, but I never bothered with that.
Yes, I leave it at the same width for all feature types and layers.
One interesting venue might be thicker extrusion width for infill, saving a bit of time as long as you're under the volumetric limit of your hot end.

The idea that you can't print smaller than the nozzle is a myth. https://3dprinting.stackexchange.com/a/14676/11157


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After print failure cant extrude PLA
I had a failed print lastnight and a glob of pla surrounded the hotend. After heating it up and removing the glob the extruder does not release any significant material. I checked with OctoPrint and the extruder stepper does push filament without the hot end on.
After fully heating the hot end I was able to remove the nozzle.
I then pushed the previously melted PLA out of the tube and heater. It was discolored in the heater. I then tried to put the nozzle back on and pull the old PLA out of the nozzle but no success there.
Should the nozzle be left in acetone for a few days  before trying again or how should this be dealt with. The nozzle appears to be blocked.

Does this answer your question? Is this hot end salvageable? or Heatercartridge Bolt Stuck?

Acetone works on ABS, but not on PLA.  If ABS is carbonized even acetone won't work.  I've given up on cleaning nozzles if the filament won't push through.  It's much work with little success.

Trish the hot end salvage has some decent info in it I would say the answer below best fits my question which is related to the hot end but only about the nozzle.  it might be worth combining the info together. the heat gun + acupuncture needle might save it.  im also tempted to use fuel injector cleaner to see if the nozzle can be cleaned that way as mine does have deposits on it just for giggles. since carbon is not soluble at all and only die/impurities/oil can be affected to attempt to remove the carbon ill have to update later after playng around.

If the hotend is okay, consider yourself lucky and consider the nozzle a loss. Aside from specialty items like ruby tip ones, nozzles are a consumable anyway. Even if you can clean it out well enough to get it working again, it's unlikely to extrude as well as a new clean nozzle. Acetone is probably not going to help; PLA does not dissolve in acetone, and while the pigments/additives might be affected by it enough to weaken and deform PLA in a way that could get it to detach, what's clogging your nozzle is likely burnt/carbonized PLA that's unlikely to be removable by anything that won't also destroy the brass.
If you don't already have replacements on hand, get yourself a pack of 10-20 for $10 or so and be ready to replace when needed. You can also go for a mixed-size pack if you want to try printing fine details with a smaller (0.1-0.3 mm) nozzle or super-fast but rough with a large (0.8-1.0 mm) nozzle.

After reading that carbon is pretty much chemically inactive except to oxidizers I went and grabbed a pack of nozles of various sizes. hydrogen proxide and white viniger may also be worth trying but we shall see...

Nice. I find that getting a mix softens the blow of having to buy new nozzles for the first time when the minimum quantity feels like more than you'll need, since you get not just a replacement but also more sizes to play with. :-)


text:
Aggressive resin solvent
For the purpose of cleaning, I need an aggressive solvent for cured or partially cured resin that will degrade resin down to its liquid state. I'm looking for one that would eat out specifically resin (I'm using regular Anycubic green resin) in a rapid fashion but would leave painted / metallic parts and screen of my 3D printer without damage.

Concentrated nitric acid will remove all organics, including your skin, wire insulation, etc.  It will work on a glass plate, but the fumes would eventually damage the plastics on your printer unless you remove the glass plate to clean it.  Nitric acid will destroy most build surfaces that are added to glass.  To a lesser extent concentrated sulfuric acid works, but it tends to leave carbon behind.  With these acids it takes special gloves, and I would not even depend too heavily on them always working.  The more concentrated the acids (the less water), the less they will attack metals.   Note: this will quickly strip the paint off metal parts.
Thus, you probably cannot find an aggressive chemical that is practical for you to use.

Acids destroy the polymer

@Trish: Are there less aggressive acids, such as acetic acid that would destroy the polymer?

I.. don't think so. Anything that can't even break up proteins - which are basically super fragile polymers - can't have a chance against a photocuring resin.

@Lu4: Keep an eye on recycle methods for resin polymers to see if they come up with something.

There is something even more aggressive on hydrocarbons, that would work on glass plates, but attacks metal aggressively.  It's too dangerous for this application, but used in the semiconductor industry before metallization.  It will destroy gloves and strip your hand to the bone.

There's always the Fluorine option.......

Fluorine will etch the glass. Piranha etch doesn't attack the glass, but gets it very clean.

Besides the trouble to even get hydroflouric acid, yes. Flourine and its acid are the most destructive material known to man at room temperature. IT's pretty much the nuclear option of chemistry.

Hydrofluoric acid vapors will frost glass and are poisonous to breath.  Piranha etch is difficult to handle.  It will destroy any hydrocarbon, even carbon.  Thus, one can't use chemical gloves or even metal tools.  One would need glass containers and holders to dip the glass bed into the etch.  Piranha etch has a short lifetime and if not mixed properly, when making it, will splatter violently.

@Trish For an amusing read, you might like Things I Won’t Work With: Dioxygen Difluoride. (There are more in that series.)

Wear Gloves.
Returning is impossible
Resin does not just harden, it polymerizes into shape from monomers in a chemical reaction. That means to break it down, you need to destroy the whole chemistry. There is no solvent that can simply reverse it.
Wiping is easy
As long as the rein is still liquid, you can wipe it off. Then clean the parts with Isopropylic alcohol.
Manual work
Destroying Resin-Polymers is incredibly hard for most solvents. The most simple solution is usually oddly enough to use physical force. Resins are super brittle and chip off, but might damage the paint coat in the worst case.
Thermal shock
If you can, you might put your printer in a cold environment and see the resin gaining cracks, as it shrinks slower and less than the metal. Then, putting it back into the heat adds more.

I would try hexane, and then Dichloromethane and if those did not work, I would heat up sodium hydroxide to about 70-90 °C. These would work better if you print in PLA resin, it's available from a few sources now.
Bucktown polymers and 3Dresyns both have a water-soluble resin. You could also print, make a soft silicone mold, cast in chocolate or isomalt and quickly seal in b72 enamel to hold its shape for your next step.
Another great option is to cast the printed mold with Amazing Remelt as you can microwave it out of your shell afterward. Or heat up/steam.

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

Hot sodium hydroxide solution will dissolve glass.


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Is there a way to make a watertight model? Is there a spray that may work?
This is a specific model for a specific reason. It's shaped like a cylinder and has a recessed bottom. I'm using a Flashforge Adventurer 3 with Flashforge filament. I tried Sunlu silver/silk PLA+ but my Flashforge didn't like it, so I took the recommendation to use Flashforge filament. It worked just fine, but when I put water in it, it has leaks.
I was printing at 210 with a plate temp at 50. Like I stated, I was excited except for the fact that it's not watertight.
Since I'm new at this process, my first thought was there must be a food grade spray, or close to food grade, that could seal the model after I touch it up.
Does anyone know if there is one available? Or are there settings that I need to address?
Thanks in advance for any comments.

Plastic coating sprays are a thing, though probably far from food safe.

There are several ways to ensure water tightness:
Thicker walls
I have experienced that 3 walls and 5 tops/bottoms with an outer shell of Concentric while the core is lines become watertight enough that leakage is almost none.
Lacquer
The oldest known method to seal a piece of porous material is a lacquer, followed by glaze. Glazes require to be burned at some thousand degrees, so are out, but lacquers are simple and easy. Basic clear acrylic lacquer can be used to seep into all the cracks and crannies and then harden out. It's easy to apply and cheap from home depot. Polyurethane lacquers also work. If you look to use it for food, ask if the lacquer is food rated in home depot.

Thanks so much for your input. One more quick question, should I use acrylic or polyurethane?

@Bro.Paul both are good, but I prefer acrylic.


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Intermittent lifting (Creality CR-6SE + glass bed + stock PLA) issues

Creality CR-6 SE 1.0.2
Creality Slicer 4.2.1
stock PLA roll
Slicer settings: Default (generic PLA) 0.2

Having intermittent issues where prints (usually edge) would "lift".
I replaced the bed, and the filament, and I don't see this issue anymore, but..
I'm a new student of 3D printing, I want to understand why issues happen, and not just how to patch/workaround them.

This is a classic example of not enough adhesion. Adding brim, more temperature in the bed and using an adhesive like glue stick, hair spray or a dedicated print adhesion spray solved the issue. See e.g. this question which is very similar.

Thanks! I postulated that it was either adhesion issue or cold bed. I may have inadvertently improved this issue by switching from glass to PEI bed, but, as always, it's good to understand why things happen and learn properly.


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Crashed while printing (adhesion issue? Level issue?)
Printing with "Amolen bronze PLA", success with smaller prints.
Decided to print the "Fillenium M", but it crashed at 50 % during the print.
I assume the print fell down (due to raft failure).
Or, it might be some other issues (no idea?).
Temperatures are:

Extruder 190 °C
Bed 50 °C

In your experience, what would be most likely culprit?
Picture attached below (see the notch where the nozzle crashed into print)

Amolen Bronze PLA
Creality CR-6 SE 1.0.2
Creality Slicer 4.2.1

It is very hard for us to answer this question, there are too many unknowns. Generally, the use of a raft is not necessary and from the image cannot be concluded that the raft is the issue. Bed temperature for PLA can be seen as too low, but that depends on the used filament.

Thanks. I should finish my octoprint box. That'd be handy for fails like this one.


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Gluing silicon heater to aluminium
I am making a bed for my 3D printer. I have bought a silicon heater (31x31 cm) and I want to glue it to my custom aluminum bed. The tape that it had from factory was bad, so I removed it. I want to glue it to the aluminum and I don't know what type of adhesive to use, I was thinking gasket glue with silicon, but I think that it will have bad thermal conductivity. I found this product, a silicon based,  heat transferring paste, but I think that it will not stick good. What is a good adhesive for this purpose?

Heat Transfer PAste will not work as a gluing agent. What you need is a high-temperature glue that bonds Aluminium and a silicone rubber. The benchmark temperature that the glue needs to withstand is about 100 °C or approximately 200 °F.
McMaster-Carr allowed me to search for glue-properties and suggests among others contact adhesives, which are cans or tubes with a very viscous glue. You let that pre-cure on the items and then push the two together, resulting in very strong bonds. One of the items they suggest is 3M 2262 for which McMaster-Carr lists 230 °F as the max temperature, so just in the safe range. However, a 32 oz. can for almost 100 $ is surely overkill, the 3M manufacturer catalog lists only 1 qt and 5 gal as the available packaging sizes, so, unless you build printers for a living or know someone who uses this industrially, this is not an option.
The same catalog also lists the "3M™ 200MP& 300LSE" series with temperatures of 148 °C (300 °F) to 204 °C (400 °F). That is enough to print anything on. And it's the same glue that' used on my Build-Tak replacement surfaces to stick them to the Aluminium bed, so it could be suitable for gluing the heater to the bed on the other side too. However, I wish you good luck to find a reseller that sells you a fitting amount. Industrial packaging is available, but you'll need to find a reseller that offers a somewhat fitting size for you - I have seen Amazon listings for both types in sizes that have only small waste for most common heaters.

I am not affiliated with 3M or McMaster-Carr, but I have very good experience with 300LSE.

Thank you for your response. Theese double coated tapes are very expensive, 20 euro for a sheet of 31x31 cm. I was thinking to glue it with a thin layer of gasket glue. I can't find the thermal conductivity, but I don't think it will be so bad.

I have seen 25x30 for a 5er, but yes, the stuff IS expensive: 1000€ for a 55 meter, 65 cm wide roll from the industrial resellers. Thermal conductivity is good enough that it'S common to use 300LE or 200MP for the BuildTak.

I suggest not gluing it. Starting from the top, make a sandwich this way:
Aluminium with holes for bolts - Silicone heater - Thin cork (the one from IKEA, 2 mm thick for office desks is fine) - Thin plywood with holes for bolts (or other stiff material holding at least 60°C)
This way you use the aluminium and the plywood to keep the silicone heater well in contact with the aluminium, and the cork insulates so that less heat is lost on the bottom side.
Also, cork is fire-retardant.
If the heater fails replacing it is simple.
Also, you can and should cut away from the cork some space for a thermal non resettable fuse at 180°C to cut power if the heater overheats.
In my case I should have used one more bolt, as you can see in the photo.

Thank you for your response. I am afraid to put a sheet of plywood under the heating element. Beside that it is not a bad idea.

@KostasLazaridis it's not just plywood, it's plywood under cork, which is fire-retardant. You need a temperature safety fuse anyway! Trust me, plywood will be barely hot to the touch. https://en.wikipedia.org/wiki/Thermal_cutoff#Thermal_fuse


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How should you run PTFE (Teflon) Tubes?
I bought a modern machine, and it comes with PTFE tubes.  I need to relocate the spool, so I bought some longer PTFE tubes.  I bent the tub by hand, and my first test run actually had too much friction, so the extruder was unable to pull the filament through the tube.  I cut it a few inches and it seems to be fine.
What are the rules of thumb that one should use when redesigning a filament path though a PTFE tube?  For example, these are some things I can think of based on how I would teach someone about running wires in a high- or low- voltage commercial application (with or without conduit):

Bend radius.
Number of bends.
Length of tube.
Diameter of tube relevant to diameter of filament (link).
Expected friction coefficient (teflon appears to be slick, but will still have some friction)
How to secure the slippery tube (clips, zip ties, glue, etc.).
How much compression is too much for the tube (ie zip ties)?

PTFE tube usually can be used unconstrained

That's vague with a side of vague-sauce and 2 sides of vague right next to it.  If there's not at least 1 point of constraint, the tube will get eaten by the extruder.

Let me rephrase: you don't need to constrain the PTFE-tube other than for the fitting to the extruder and the hotend usually.

@Trish oh, that makes more sense.  In this printer, the tube is not constrained at the hotend and is used midway of the filament path, so it has to be attached in at least 1 place.

photo please...

Constriction
PTFE-Tubes usually have enough stiffness to not require additional support and constriction from anything but the two end fittings and the stiffness the filament in them provides. In fact, they make great guides for cable management to the heater block! You might want to add some constricting clamps on very long tubes. To do so, zip ties and cable guide clamps are common. Don't make them too tight as they shall not cut into the tube!
You also shouldn't constrict them too tight: A bend diameter of about 12 cm is where I would pull the line for 1.75 mm PLA: anything lower and you might get problems. For 2.85 or 3 mm filament, you should use a somewhat larger diameter - I have seen good flow with about 20 cm bends. A very simple test can be done: Fix one end, load filament, pull at the other end while holding the second fixture close to the planned position. If you have an easy way, you're good.
Length
Length is tricky: you should not be too long, as that could add too much friction, but on a direct drive or when you pull filament from a dry box, there's little to no length limit on the tube through which you pull, there's only a maximum length you can push through effectively.
Diameter
The diameter of a tube on the pushing end of the extruder motor should be somewhat snug: 1.9 and 2 mm inner diameter are common for 1.75 mm filament, and 2.85 mm does work well in a 3 mm tube. 3 mm filament needs about 3.25 mm inner diameter. As a rule of thumb: add 0.15 to 0.25 mm to the diameter of the filament and get the closest available diameter to that.
On the pulling end of the extruder, a larger size can be used. Though don't go too large, like 10 mm ID, as at some point, as you might experience backlash and rattling in the tube, resulting in noise, and for very hygroscopic filaments (PVA or Nylon), the extra air in such a large tube could reduce the effect of printing from a dry box:

3.25 mm works well for both 2.85 and 3 mm and might still work for 1.75 mm filament on the intake side (Thank you for the insight FarO!)
a 4 mm ID on the intake-side can still work for 1.75 mm and mitigate extrusion problems on a Bowden-extruder (thanks @0scar)

In either case, you have to keep in mind the bending radii - don't overconstrain! Also, remember that you need to have a fitting coupling on the delivering and the receiving end.

I think he is asking about the PTFE tube from spool to extruder. In this case, the tube can be quite loose and you can use 3.25mm ID for everything: 2.85 mm filament, and for 1.75 mm filament. There is no issue resulting from too lose tube between spool and extruder. It's actually better: less friction and load on the extruder gear.

Let us continue this discussion in chat.

This is good info!  But my application does not have the tube attached to the hotend, nor any fittings.  It's a Monoprice Inventor, which I believe is a rebranded Flashforge Inventor , so there's a ~4" tube in the middle of the filament path as a guide and strain relief.

@YetAnotherRandomUser that's a direct-drive hotend, not a bowden.


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Cura 4.8.0 Custom Infill using Shape Overlap Modifier not working
I am using a rectangle to select an area of the model I want to have 100 % infill. You can see my setting below. After several prints, I noticed the little arm was still breaking when under pressure... and sure enough my infill setting had not worked. In looking at the preview in Cura, you can clearly see it is not applying the 100 % infill as you can see set to the left... what am I missing? I have tried several infill types,(lines, hexagon...) to no avail.

Hi welcome to 3DPrinting.SE! This question has been asked before and is explained in this answer. If that procedure is not working anymore (I will check later and update the answer if necessary), you might have found a bug in a more recent version of Cura, please notify the developers. We might close this question as using a different infill is asked before, unless there is a reference for this new feature.

I have just tried to increase the infill to 100 % of in intersecting body in Cura 4.8, it still works. Both for inserted STL files as for "eraser" objects created by Cura. Therefor this answer should solve the issue. Try to remove the STL that is not in the build volume first, or move it into the volume.

I dont understand. In my photo, you can see the preview screen with all my settings. The infill is 20%, and the box is set to modify overlays, and is set to infill 100%, yet as you can see in the preview screen, the area inside the box is not 100% infill. What am I missing?


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Filament sticks to nozzle
Normally, I'm all fine with my printer and filament. But today I changed the filament for another brand and no matter what, it sticks to the nozzle so nothing comes to the bed and soon my nozzle is full of PLA... I use a sheet of paper for printer to level the bed at 0.1 mm. While leveling, I get the nozzle close enough to feel a bit of resistance from the paper while moving that sheet. Please help me...

What temperature are you running your nozzle/bed at?

Eric, were you able to resolve thanks to any answer below? Or would you like to share some other advice? This question reflects issue of many, it deserves to be resolved :)

I believe the problem is not so much that the filament is sticking to the nozzle; it's that the filament is not sticking to the bed.
You've confirmed that you have correct clearance for the nozzle to bed distance. The next considerations are bed temperature and nozzle temperature. New brands often require new parameters.
Consider to raise the bed temperature 5 °C. If you're not using any adhesive medium, perhaps a bit of glue stick will help to have the filament stick better/properly.
It's unlikely that the nozzle temperature is incorrect, as too low would result in a nozzle clog, while too high would "drizzle out" and be everywhere, but don't reject too-high entirely.
If you can get the bed adhesion correct, your nozzle should remain clear.

In addition to @fred_dot_u remarks:
Decrease initial layer speed
Try to print the initial layer at lower (very low speed). Start from 20 mm/s, move down even to 5-10 mm/s (e.g. just decrease speed% from the menu). I had many such issues when printing in too high speed (even directly on kapton tape): filament could not stick to the bed so quickly and rolled just after the nozzle - and slowing down almost always helped.
You may also decrease height of first layer e.g. by 25-50 %, and try to increase "Initial Layer Line Width" (e.g. 120 % in Cura). Increase temperatures by 5-10 degrees also helps sometime.
If this will not improve, then try to enhance adhesion.


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Printing files over USB drive (Ender 3 Pro)
Is this possible? I know that the controller board of the printer is normally controlled (when using USB) by an active computer sending data, but I was wondering if it could be reversed so that the board retrieves files from a USB flash drive? My SD card keeps failing and is overall frustrating to work with, so USB would be a nice option.

Unfortunately, no.
There are two types of USB devices: host, such as a PC, and device, such as a thumb drive. (Actually, there is a third type, on-the-go, which can act as either.)
The Ender 3 mainboard is a USB device which means that it can only connect to a USB host. You cannot directly connect two USB devices, such as the Ender 3 and a thumb drive) and have them work.
One option would be to set up OctoPrint software on a Raspberry PI single-board computer and connect that by USB to the printer.

benefit of OctoPrint: you can start (and monitor) print jobs from the LAN