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Everything posted by geert_2

  1. First clean the build plate with luke-warm clean water only, multiple times. No soap, no detergents. Then gently wipe the build plate with a tissue with very salt water. Yes, salt. Gently keep wiping until it dries and leaves a thin mist of salt stuck to the print bed. Then print on a heated bed at 60°C. I would recommend printing with the biggest surface downwards, as in the second photo. When hot, the model should stick rock-solid to the bed. After cooling down, it should pop off without any force. For me, this "salt method" has worked very well for over a year and over a 1000 models now, often difficult models. See the full manual with pictures at: https://www.uantwerpen.be/nl/personeel/geert-keteleer/manuals/ I have only tried this with PLA. I do not really expect it to work with other materials, but of course, feel free to try, and let us know whatever your results are, good or bad. Hope this helps. Geert
  2. I guess you already did this, but just to make sure: could you verify in Cura that the checkbox "Enable retraction" is checked indeed? Then verify in Cura, in Layer view, that extraction is active (=small dark blue vertikal lines). It could have been disabled accidentally, or on purpose to try something, but that you have forgotten to enable it again? Geert
  3. Is it possible to install (and uninstall) different versions of Cura in parallel, without them influencing each other at all? Thus also without automatically importing any settings? I could not find any info on this in the manual or FAQ. I would like to try the new versions, but without messing up my working version (Cura 14.09, on Windows 7 Pro, SP1), which I need for production of prototypes against deadlines. So the existing setup should remain stable, even though it may be "old". If not possible, what about adding it in future versions, For example by offering the following radio-button options during installation: O Update existing installation O Install the new version independently in parallel And if the user selects the "independent" option: O Import settings... [select Cura version to import from] O Do not import anything, start with factory defaults Something along this line? (I haven't tried running it in a virtual machine yet, but with the limited amount of memory, 3D-acceleration, and disk space available to virtual machines, that might cause other problems. Geert
  4. If the problem is that in mid-print, the print bed suddenly moves down, but the printer just keeps printing as if nothing happened, then this could be caused by the motor drivers (amplifiers) getting too hot. Then their temperature protection activates for a few moments, so the stepper motor gets no more current, and the built plate falls down a bit. There has been a recent post on this in the hardware section: https://ultimaker.com/en/community/20998-ultimaker-2-motor-drivers-overheating Could that be what you are seeing? Geert
  5. That is really cool. I am actually surprised that it works without leaking everywhere between the seams, on this small scale. Geert
  6. - I would prefer the list of posts (and the lists of forums) to be more dense, thus with less vertical white space in between them. And with more items listed on one page (or maybe user-adjustable in our profile?). So that it is easier to get an overview. The amount of information that is presented per item is okay. - I really don't like the blue pop-ups jumping over messages before I am logged in. These days a lot of people surf by opening in the background 20 posts from a list, by middle-clicking each. So, then I have to close that same blue pop-up 20 times, if I forgot to login first. Thus usually... This is really annoying. Most of the time the blue thing also pops up while I am busy logging in, so I have to start all over again. I would recommend throwing that out completely. So if you want to pick only one item from this list, take this. - The Sign-up button could say "Login/Sign-up", and could default to the login screen, since people have to sign up only once, but after that they have to login many times. Maybe there is a faster way to login, but I haven't found it. But I haven't searched either. - These forums contain a lot of very valuable posts and tips and tricks, very educative. But sometimes they are difficult to find, as they get snowed under tons of new posts. The best posts are worth converting into manuals. What would you think about a forum named "Manuals by users", or something similar? Where only those manuals are listed (after approval), but no discussions? Just a long list of Manuals / Tips & trics only? - I like to print valuable posts (to PDF-file) and store them locally, in my directory 3d_printing_tips. But the forum pages are not easy to print, so I have to copy and paste everyting into a text editor, clean it up, then print to PDF. If other people do this too, maybe you could add a print-CSS sheet to the website that removes left and right side panels, and cleans up the body text for better printing? But this has no priority. - Personally, I prefer very simple menus in the old style, like on this site: "www.interthk.be". (That's why I made it that way, even though it is very primitive and old-fashioned, but I just like it that way.) Or menus as on the GRC-site: "www.grc.com", which has very nice, very compact, but very modern pull-downs. Also very minimalistic, so that leaves a lot of room for the real page content. This is probably the best I've met (although not the most beautiful). You might want to check that out. The point is that I have trouble finding my way in these modern menus with "hamburgers" and lots of other meaningless (to me) icons. As in the recent Firefox-horror (so I switched to Pale Moon). But I can imagine that younger people - or mentally younger people - see things differently. Anyway, the good things are: (1) the Ultimaker forum does exist. And (2) it does work well technically. And (3) it is used a lot and contains good info. I appreciate that very much! So, don't throw these good things out.
  7. My first thoughts: - Something is scratching the case, as neotko says. - Or something is stuck between moving parts (slide blocks or wheels) and the case. - Or the rods and slide bearings are so terribly dry that they can't move at all, and start making a screeching sound. Like in cheap cheap computer fans, with worn-out bearings. But here on a lower frequency. If the rods feel totally dry, try gently lubricating them (but don't pour oil on the rods; do the oil on a tissue, and use that to genlty wipe the rods). - Or some debris got into a bearing and almost blocks it, or a broken bearing. - Or a severe mis-alignment if something came loose or if the printer got dropped or hit during transport. Try borrowing a stethoscope (like doctors use to listen to your breath) to find out where it comes from exactly. Car dealers and repair shops also use this to locate weird engine sounds (I saw one using it on my car once). Or try making one yourself from PVC tubes, it might work.
  8. If only fume extraction is important, you could look into soldering fume extraction systems? In the old days we had a sort of desktop bureau lamp with built-in fan and active carbon filter. No bigger than a normal desktop lamp. So you had a lot of light when soldering, and the fumes were taken away. But I don't know if active carbon filters out PLA and ABS fumes also. Just blowing them around, wouldn't improve safety... (My Ultimakers are in a chemical fume extraction cabinet in our lab, since I have it anyway. Doesn't seem to cause problems with the draft for printing PLA.)
  9. I found that stringing and "hairs" do mostly occur when: - printing rather hot, - printing fast (which requires printing hotter), - when increasing the flow rate and overextrusion happens, I noticed that strings occur when filament is leaking out of the nozzle opening. And hairs occur when molten residu is accumulated on the nozzle tip, and is sagging and touching the print. Or when the previous layers are overextruded or curled up, and the side of the hot nozzle touches these raised parts. Most materials string more when hotter. So, as yellowshark says, I would suggest you try printing slower and cooler. Print the same object once again just for testing, and keep watching it. Then play with temperature and speed settings. E.g. reduce temp in steps of 5°C, wait a few minutes and see what happens? I realise this is an older post, but it may help others in the future.
  10. I noticed that parts with big overhangs tend to curl up. The printer has to print part of those layers "in the air", so it has no good support. These overhanging edges can curl up quite a lot, even one or two millimeter. What may happen next, is that the print head brutally collides with these ridges, and knocks the print over. I have seen it happen in a testprint. Could this be the cause? If you have a compressor, you could try blowing cool air on the surface, to make it cool faster and get less curling up.
  11. It depends on whether your models are mainly geometric machine-like parts, or rather organic parts? To start with geometric models (machine parts), I would suggest you have a look at DesignSpark Mechanical, which is a limited version of SpaceClaim. Legally free. This is rather easy to learn, and you can find a lot of good tutorial videos online. For organic shapes, Blender is very powerfull freeware, but not that easy. Maybe you could also have a look at a modeler such as Form Z (www.formz.com), which is more geared towards architecture and product design? It is not free, but the price is still acceptable. Their user-interface is also quite easy to learn, very intuitive. And they have free trial versions. Probably also free student versions (requiring proof).
  12. We don't have one, but I have seen one in use at a local distributor last year (I don't remember the brand). I found it rather disappointing: it couldn't scan inside an empty cup, under armpits, under a nose, under a car model, in an open mouth,... All these very common things left huge open gaps and/or defects. And then, once you had the scan, you could not really work on it, it was a huge mess of mesh. It only worked well for very simple objects, which you could as well design in 3D. So, whatever your scanner model of choice would be, I would suggest that you go to a local distributor, and have him scan your typical objects. And let him go through all the post-processing, editing and cleaning-up in front of your eyes. I think that is the only way to know if it is good enough, and if it is workable for you. Also carefully verify that the scanner produces watertight solid 3D-models. Often 3D-scanners will only produce surface-objects (even with holes in it), that you can not 3D-print. These surface-objects may be good enough for rotating an image on-screen, e.g. for a game or for 3D-visualisation, but not for printing. You really have to see it with your own eyes, I think.
  13. Could this sort of problem be caused by long common ground wires, used for both power and sensing? Or something similar? So that some reference shifts up or down when a high power device (e.g. heat bed) is switched on and causes a voltage drop in these lines? I don't know the board schematics, so I am just guessing. Further, what part of the printer exactly causes the EMC-overshoot? Heated bed, wires, controller board,...? Could that be handled in a simple way by adding an (bigger) earth-line somewhere, or by shielding? In that case, might it be possible to officially say that: "On the condition that you modify your printer so and so, the bed-PID may be enabled"? Or would that violate the laws too?
  14. When doing an atomic pull, if you have a thick blob in the area where the nozzle meets the teflon coupler, this means the teflon coupler is deformed: it has become wider at the bottom. I had the exact same thing after a few hundred hours of printing. If you do a normal atomic pull (=with pulling very hard) you risk dislocating the nozzle or teflon coupler, or even bending the rods. I would suggest you try a more gentle atomic pull, as described in my manual here: https://www.uantwerpen.be/nl/personeel/geert-keteleer/manuals/ This has far less risk of doing damage, because it is specifically designed to prevent that thick blob, and it requires only very gentle pulling. But that of course does not repair the basic problem: the worn out teflon coupler. So I suggest replacing the teflon coupler too. Further, if you are near the end of the filament spool, where filament is wound extremely thight, I suggest you manually unwind a few meters of filament and manually straighten them a bit. Then let it roll up on the spool again, so that it is now sitting very loose on the spool. A bending radius of 30cm is optimal for minimum friction in the bowden tube. A straight filament is optimal for minimum friction in the nozzle. So a bending radius of 50cm seems to be a good compromise and works best for me. Found out by trial and error. Geert
  15. After each print, when I am in the neighbourhood and I hear the printer finishing, I immediately clean the outside of the nozzle while still hot, by using a thick (!) tissue. Also when doing an atomic method, I often clean the outside too. I refer to this as "wiping its poop hole", to avoid confusion with cleaning the inside of the nozzle (atomic method). This also gives cleaner prints, since there is no brown residu sagging and leaking onto the next prints.
  16. Thanks for trying it with different materials and letting us know. I did not expect the salt method to work with other materials than PLA and PLA/PHA, so I am very interested in the results. Thus it seems to work a little bit, but not that well? On PLA indeed, when hot the bond is rock solid. When cold it pops off automatically. It has done so very consistently for over a year now, on about 1000 prints. Concerning the sugar method: for now I have no need to, but if I ever want to print in ABS, and if the salt method would fail (as I expect), I will for sure try the sugar method next, because I like the idea.
  17. Instead of using glue, you might try wiping the glass plate with salt water, prior to printing PLA. Gently keep wiping the plate with a moist tissue, until the water evaporates and leaves a thin mist of salt on the glass. This *greatly* improves bonding of PLA to heated glass. When hot (60°C), my prints bond rock-solid to the glass, I can't pull them off. But when cold after finishing, they come off without any force at all. But it does require a heated glass bed. For me, this works much better than printing on bare glass, or with glue. And you don't need to remove the glass from the printer anymore. And salt is cheap too... :-) See my manual (PDF-file) with lots of pictures at: https://www.uantwerpen.be/nl/personeel/geert-keteleer/manuals/ I hope this helps.
  18. I would suggest you try wiping the glass plate with *salt water*, prior to printing PLA. Gently keep wiping with a moist tissue, until the water evaporates and leaves a thin mist of salt on the glass. This *greatly* improves bonding of PLA to heated glass. When the glass is hot (60°C), my prints bond rock-solid to it, I can't pull them off. But when cold after finishing, they come off without any force at all. So for me this is the perfect solution, much better than the "glue stick method" I tried before. And you don't need to remove the glass bed from the printer anymore. But it does require a heated glass bed, won't work on a cold bed. Since I started using this "salt method" one year ago, I printed about 1000 parts, often very complex, long and 100% filled parts, without warping. (Only one inverted prism came off). I tried different bed temperatures, and the default of 60°C seems to work best. At 50°C it still works, but you may get minor warping at corners of difficult objects (big, 100% filled, with chamfers). At 70°C bonding itself is better, but the PLA gets too flexible, so warping forces can easier peel it off. Thus 60°C seems to be the best balance for me. See my manual (PDF-file) with lots of pictures at: https://www.uantwerpen.be/nl/personeel/geert-keteleer/manuals/ Hope this helps. This method probably only works for PLA, but I haven't tried any other materials. So I would be interested to know about other materials. Geert
  19. I suggest you try wiping the glass plate with salt water, prior to printing. Gently keep wiping with a moist tissue, until the water evaporates and leaves a thin mist of salt on the glass. This *greatly* improves bonding of PLA to heated glass. When hot (60°C), my prints bond rock-solid to the glass, I can't pull them off. But when cold after finishing, they come off without any force at all. So for me this is the perfect solution. But it does require a heated glass bed. Since I used this "salt method" one year ago, I printed about 1000 parts, often very complex, long and 100% filled parts, without warping. (Only one inverted prism came off). See my manual (PDF-file) with lots of pictures at: https://www.uantwerpen.be/nl/personeel/geert-keteleer/manuals/ Hope this helps. This method probably only works for PLA, but I haven't tried any other materials. So I would be interested to know about other materials. Geert
  20. After cleaning, thoroughly wash the glass several times with pure tap water only. No soap, no detergents, no cleaning aids anymore: they all reduce bonding. Then wipe the glass with very salt water. Yes, salt water. Keep wiping gently and let the water evaporate, until the salt dries into a very thin mist. To print, heat the glass plate to 60°C. This "salt method" gives a far better bonding of PLA to glass: when hot, it bonds rock solid. But when cold, the models fall off automatically, without any force at all. Since I started using this "salt method" one year ago, I have printed about 1000 parts in PLA without bonding problems. Often very difficult parts that I could not print with the "glue stick method". No warping, no corners lifting. See the full manual with pictures at: https://www.uantwerpen.be/nl/personeel/geert-keteleer/manuals/ Let us know if this helps. (But I think it will only work for PLA.) Geert
  21. I think it might be two effects combined? - The 45° diagonal irregular extrusion might be a feeding problem (dirty nozzle, filament diameter variation, friction variations, worn teflon coupler, whatever...). - But the too thin areas parallel to the print head rather seem to be a glass problem to me. Glass plates are never perfectly parallel, they have variations in thickness. (Just like plastic or metal plates.) In a window this is often visible: you can notici it when the landscape behind gets deformed when looking through the glass. Or it could be warping of the glass due to heating? I have this too on one of my printers, always in the same place, and it can't be leveled out, because that makes other areas worse. It only shows up when the first layer is 0.1mm, not when it is 0.2 or 0.3mm.
  22. Wow, that's a beautiful one. One tip: don't leave it in your car in the sun. I have had several PLA-models warping even in moderate weather (about 15°C, and a light sun with thin high clouds).
  23. Couldn't this be caused by underextrusion or irregular extrusion too? Possible causes of underextrusion that I experienced: - White teflon insulator on the nozzle is worn out and deformed internally, causing an irregular flow. (If this is the case, replace it.) - Dirt in the nozzle (if so, do an atomic pull). - Irregular filament diameter. - Filament is near the end of the spool, and/or wound too tight, so it acts like a tough spring resisting unwinding. I often manually unwind and straighten a few meters of filament, which greatly improves results. - Irregular friction between the filament spool and the spool holder (black cylinder at the back), causing a jerky movement of filament, and thus irregular flow. I am not saying one of these things is the cause, but they might be worth examining?
  24. Hello all, I developed a method to get a better bonding of PLA to a heated glass bed by treating the glass with salt water first. So I named it: "the salt method". Since using this, I made about 1000 prints in PLA, often very difficult ones (100% filled, very long and thick, with big overhangs and chamfers), without any bonding problems and without any corners lifting. Often models that I could not print by using the glue stick method. The only failure was an inverted prism (top down). With this "salt method", PLA sticks to the glass rock-solid when hot, but come off by itself when cold. (This method probably only works for PLA.) Furter, I improved the well known "atomic method" to clean the nozzle: the standard method works very well in cleaning, but it has the risk of damaging the printer due to the hard pulling. My approach is much more gently, but with equal cleaning results. The disadvantage is that it takes more time. I have been using both methods for some time now with good results: the salt method for over a year, and the improved atomic method for over a month. So I wrote a manual about each. See my personal page at: "www.uantwerpen.be/geert-keteleer". And then go to the "Manuals & 3D-models" section. Both manuals are PDF-files of about 2MB. There you will also find and improved horseshoe clip for the Ultimaker2 bowden tube: it is much easier to grab, without risk of dropping it. Feel free to print it and try it. I hope these things are usefull. Everything is published under a Creative Commons BY-SA license, so you can use it for free (also for commercial purposes) and further improve it. I would welcome comments on how well these methods work for others too. Geert
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