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krikru

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Everything posted by krikru

  1. Okay, I apologize but I assumed that either you were a developer or that at least the developers would read the threads that had been tagged as "Bug" here, since this is Ultimaker's own forum. About the gap in the model, I'm not a structural engineer, but I think a 0.2 mm gap between lines that are only 0.4 mm wide themselves can potentially have a quite large impact. Similar to how Cura ensures that a support comes off easily by adding a vertical gap between the model and the support, I think the bonding between the two extrusion lines is likely to be compromised if there is a horizontal gap between them and act as a weak spot should the model need to take some load (if the two lines wouldn't even touch physically, there wouldn't be any bonding to speak of at all). When watching some of CNS Kitchen's videos (this channel investigates how different print settings and methods affect model strength; I can recommend it if you haven't seen it), it becomes apparent how much different things can affect printing strength. Hopefully you're right though and that it's fixed in Cura Arachne.
  2. Why should I do that work? Doesn't Ultimaker care about Cura enough to do it themselves? I have taken the time to describe the issue completely here and you were able to reproduce it. Going to Github and reporting the bug there shouldn't be a problem for any Ultimaker developer.
  3. What do you think? Is this a bug or desired behavior? (I don't see who would want to have this behavior, though.)
  4. Gap.3mf I created a minimal working example and uploaded that. I attached an image showing a gap where there is supposed to be no gap IMO and that would weaken the print considerably.
  5. Hello? Can anyone in this community please explain this behavior? And how to remove the gap? I have also marked this as a bug, so I think that some developer should at least take a look at it if no one can explain why this happens! I'm using Cura 4.10.0.
  6. Hi, I have a model in which I want to fill in some parts completely, i.e., 100% infill density. To achieve that, I use extra models which I set to "Modify settings for overlap," place them over the regions I want completely filled, and choose "Infill Density" 100%. However, when I preview the first layer that is not a bottom layer (see inserted image), I notice that there is a small gap between the wall and the infill, which I suspect will weaken the model (which is the opposite of what I want!). Where does this gap come from and how can I get rid of it? There is no such gap between the wall and the bottom in the bottom layers (which are just below the layer currently being previewed).
  7. I agree that the fact that you have to use this workaround is incredibly awkward. I have created this feature request to make it possible to remove print settings profile overrides directly in Cura.
  8. Ah, so that is how you do it! 🙂 Okay, well then it's just me not knowing Cura well enough. A question along a similar line: If I have two objects, of which one is completely inscribed by the other object, how can I select the innermost object?
  9. When I create a new project and add an stl model and a support blocker, save the project and then reopen it (it doesn't matter whether I choose "Open as project" or "Import models"), I'm unable to select the model or the support blocker individually. It doesn't matter which one I click on; all I see is this image (the reason it's dark gray is because I have created a custom filament which is black): I can still slice the model and the support blocker will do its job properly, but I cannot select the support blocker to move it to reshape it. I can create a new support blocker, and then it seems I get two selectable objects: 1) the model and the support blocker loaded from file, and 2) the new support blocker. In this image I have selected the former: The disability of not being able to select the support blocker and the model individually, plus the inconsistency between support blockers loaded from a project file and newly created support blockers, makes this feel as a bug, so I tagged this topic as a bug. I'm using Cura 4.10.0.
  10. Hm, that's surprising; since pyramids 5 and 6 are basically just more of the same compared with pyramid 4 (if you zoom in they all look the same), my guess would be that you get the same kinds of phenomena with all sizes. Maybe I should make prints of pyramids 5 and 6 as well to see how they behave.
  11. That's true. But those are not the only holes in the print; here you can see holes higher up than the first layer (I've put the pyramid on a hook): I don't think this would work, because there are gaps higher up in the model too (as just concluded) that also need to be there in order to make the print fully flexible, so you would need to do the same thing with all layers. And even if you expand all walls with a negative value, the outer wall line still merges with itself from the "inside" (i.e., the horizontal cross section of the model has very thin parts in which the outer wall line self-intersects), hence still preventing that that flexibility. I therefore think that your only option to get a fully flexible model is to print it either scaled up or with a smaller wall width (nozzle) than intended.
  12. Enabling "Remove All Holes" didn't do anything for me. Besides, even though I want to remove the gaps, I still want to keep the walls on both sides of the gap (in order to join what's below with what's above for the structural integrity), or rather merge it into one wall. Will the walls be kept if that horizontal gap is closed? About the able, all surfaces (except the bottom which is completely horizontal) have an angle of atan(sqrt(2)) which is about 55 degrees, and the corners have an angle of 45 degrees, all much higher than 27 degrees. This gap is build into the stl file and is not going to be closed by a smaller layer height. If you scale it up without increasing the wall width, you may even get this effect. However, I used a 0.28 mm layer height in my print, but with a 0.4 mm nozzle and a 0.4 mm line width that should still not be any problem. I am printing the smallest of the pyramids for the moment, pyramid4.stl, to decrease the "iteration time" 😁 I didn't write it in my question originally but edited it in. You can seem which of the models it is by counting the number of unique "hole" sizes in the pyramid side. Pyramid 4 has four hole sizes, Pyramid 5 has 5 hole sizes and Pyramid 6 has 6 hole sizes. Each larger model consists of 6 samples of the previous model (4 in the base, 1 in the top and one upside-down right under the top, hence the word "fractal" in the model name), has twice the base length and is going to take approximately 6 times longer and use 6 times the material compared to the previous model when both are printed at full scale—if we print without the bottom layer (which I don't, by the way). For example, so pyramid6.stl should take approximatelly 6 * 6 = 36 times as long time to print as pyramid4.stl. The finest details are still equally large in all models. Hence, I'm sticking to the smallest model until I have nailed that. Wow, that is some really wonky walls you get when using Smoot Spiralized Contours! I notice that I'm also getting wonky walls when using that setting, but your walls seem to be wonkier. Do you mean 0.06 mm layer height? I don't think 0.6 mm layer height would look any better than 0.2 mm layer height (for any reasonably sized nozzle). What makes you think that an SLA printer would be more suitable than an FDM printer? The model details say "It has the astonishing property that the horizontal cross sections are simply connected and change continuously with height, so can be printed perfectly with spiral mode (or single-walled without infill)," and "The original scale is to match the limit of a 0.4mm nozzle," so it seems to me like it is at least designed with FDM printers in mind, and not for a 0.25 mm nozzle but for a 0.4 mm nozzle. When I slice Pyramid 5, I get the exact same gaps. I think you should get those too if you get the gaps with Pyramid 4, considering that Pyramid 5 is just a repetition of Pyramid 4 at different spatial locations at 100 % scale. Here is a screenshot from when I have sliced Pyramid 5: Interesting! It works for me too, but seems to work better the more wall lines I use, since all the green lines are inner wall lines. You seem to use multiple wall lines, but I want to print it with only one wall line according to the model details because I think it will go much faster and will not weaken the model. And I would like to do this only with the walls that are next to a gap, because I think this will also make all holes slightly smaller, and I don't want to make the smallest holes any less visible than they already are. No, Pyramid 6 is not any more dense than Pyramid 4. It is more detailed, but it is also bigger, so the details are equally sized as in Pyramid 4. According to the model details "The original scale is to match the limit of a 0.4mm nozzle.." I'm assuming this holds for all pyramid sizes. If you want an equally large but more detailed pyramid, you both need to go up a pyramid number, and scale it down to 50% size (and use a nozzle half the size). What layer height are you using here? In my original post I showed a 0.28 mm layer height Pyramid 4. Nice! Did you use a 0.4 nozzle? And do you get any up the "pull-apart" effect shown here?
  13. Oh, modify settings for overlaps seems so useful! I guess it can also be used for reinforcing certain parts of a model that otherwise are prone to breaking. Thanks for the explanation! I guess you are right about supports being necessary but at the same time are required in massive amounts and prone to breaking many of the thin details, unless you print them with some soluble filament (unfortunately not possible on my stock Ender-3).
  14. No I haven't, but I have used single-walled without infill, which is also mentioned in the description (and one bottom layer). I think the problem is that there is a gap in the model, which makes Cura leave out a gap in the printed model as well. What I would like to happen is that the walls on both sides of that gap is moved closer together so that they merge. Since I don't see how you would encode this in the stl file, the only hope is that it is possible to get Cura to do this somehow, so it is possible to make cura move those walls a little so that they overlap slightly? (Alternatively I could perhaps learn gcode and write a script that modifies the resulting gcode file to make it do what I want, but I see that as a last resort and something that I shouldn't have to do if Cura was fully capable.)
  15. Thanks for your analysis of the model! It seems like maybe I should try to print some less detailed model in that case. By the way, how did you divide the model into segments? Can that be done in Cura or did you use some external software?
  16. I have been printing this fractal pyramid (only the smallest version, pyramid4.stl, so far) from Thingiverse. As can be seen in a close up rendering of the model in Cura, there are tiny gaps between horizontally neighboring subpyramids, probably to guide the slicer into choosing an optimal path for the nozzle to traverse. However, these gaps seem to backfire. I keep getting holes withing layers of the print, which is aesthetically unpleasing, because mathematically, there are no holes in the fractal shape (being the top half of the Sierpinski octahedron). These holes can be seen when viewing the pyramid from the top, but not when viewing it from the side, as can the seen in the following image: Is there a way to get rid of these holes somehow?
  17. I found this incredibly detailed model of the Eiffel tower: https://thangs.com/Roboninja/Eiffel-Tower-15733 My problem is with using this model in Cura, though, is even if I scale it up to cover the entire height of the build volume (which is 250 mm for Ender-3 which I use), choose a 0.2 mm nozzle, use 0.06 mm layer height and enable Print Thin Walls, the smallest details in this print are still too small to be printed, and as a result, Cura just ignores them, as can be seen in the attached image. This is not good, as they are an important part of the model. They can be made thicker, but they should not be made any thinner or removed. Is there a way to make Cura print (generate gcode for) these details? Maybe make them thicker somehow in order to prevent Cura from ignoring them?
  18. Also, when I hover the mouse cursor over the "Line Width" setting, the popup text says "Affected By: * Nozzle Diameter". So, if there isn't any nozzle size anymore, why does this text say that the line width affected by the nozzle diameter? Has the setting changed name from "Nozzle Size" to "Nozzle Diameter"? And where can I find that setting? I'm using Cura 4.10.0.
  19. When I change Line Width to 0.2, the field into which I enter it (along with a whole lot other fields that are changed automatically to 0.2) becomes orange. Why does this happen? If I print with a 0.2 mm nozzle, a line width of 0.2 mm should be perfectly fine, right?
  20. I started tinkering with Outer Wall Line Width to see if I could print finer details by just reducing this parameter without having to change to a finer nozzle. I then saw the parameter Outer Wall Inset, and I tried to slice a few different combinations of these parameters to see what results I would get. For all combinations I had an Inner Wall(s) Line Width of 0.4 mm, except the one in last image for which I had an Inner Wall(s) Line Width of 0.2 mm, and I varied the Outer Wall Line Width between 0.2 mm and 0.6 mm. Here are the printscreens I took of the various parameter combinations: Outer Wall Line Width = 0.6 mm, Inner Wall(s) Line Width = 0.4 mm, Outer Wall Inset = 0 mm: Outer Wall Line Width = 0.4 mm, Inner Wall(s) Line Width = 0.4 mm, Outer Wall Inset = 0 mm: Outer Wall Line Width = 0.2 mm, Inner Wall(s) Line Width = 0.4 mm, Outer Wall Inset = 0 mm: Outer Wall Line Width = 0.2 mm, Inner Wall(s) Line Width = 0.4 mm, Outer Wall Inset = 0.1 mm: Outer Wall Line Width = 0.2 mm, Inner Wall(s) Line Width = 0.2 mm, Outer Wall Inset = 0 mm: By changing between these images in the Windows Photo app, it is possible to see that for all the combinations with Outer Wall Inset = 0 mm, the outer edge of the outer wall are at the same position in Cura on straight parts of the wall (can be checked by placing the mouse cursor at the edge and switching image), so it seems like this is the "correct" edge placement. However, for the combination with Outer Wall Inset = 0.1 mm, the edge seems to have retracted by 0.1 mm into the wall, which will decrease the horizontal thickness of details (thicknesses of physical walls, circle radii, etc.) in the print preview by 0.2 mm, hence an incorrect thickness—i.e. a thickness that doesn't agree with the original 3D model (if we assume that the thickness of the details in the other combinations are correct since they all mutually agree). How comes that the detail thickness changes when you change Outer Wall Inset parameter? Is this desired behavior? Or is the outer wall "pushed" out by the inner walls on the printed model (since they cannot occupy the same space), hence effectively outsetting the outer wall again by the same distance it was inset and leading to details that are just as thick on the printed model as when you use zero Outer Wall Inset?
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