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Everything posted by geert_2

  1. In a plaintext editor, search for "[space] e???? [space]" or something like that, using wildcards, and delete them all? Or set them to zero? I don't know if it would work, but might be worth a try?
  2. My first idea was also: poor bed-adhesion in that spot, maybe due to the nozzle being too far away. But if it is always and only in one corner of the model, no matter where it is put on the build plate, maybe it could also be mechanical stuttering or excessive play, when changing direction? Or both?
  3. I think it was 80°C, maybe 85°C, something around that. If you would have binoculars, or a telescope, you could try to hold them upside-down with the ocular very close to the model, close to a bright light. Quality won't be good, and you will get a lot of deformation, but it might be good enough for inspection. A telescope works exactly opposite to a microscope: the lenses are swapped (and in real life of course adapted for minimal distortion). In a microscope the little, most curved lense is close to the object, and the flattest and big lense is the ocular. For people
  4. If the filament is swollen above the nozzle and teflon coupler, could it be that your little fan that does not work (=the one behind the nozzle)? Sometimes, strands and hairs of molten filament get sucked up in it, and slow it down. Anyway, if you would want to do atomic pulls, but in a much more gentle way without brute force, you could try my old manual: https://www.uantwerpen.be/nl/personeel/geert-keteleer/manuals/ And then scroll down a little bit. This works by cooling deeper, and then gently wiggling and rotating, instead of brutal pulling. No ris
  5. Is it scratching the surface, or is it entrapping air bubbles inbetween both layers, when seen through a microscope? This also makes it opaque like frosted glass. I only have seen the entrapping in my tests: mostly in the seems between the little sausages, sometimes on top of surfaces as the top layer is not perfectly flat. (In case you don't have a microscope, sometimes a high-resolution camera with powerfull macro lens can also show this, better than with the naked eye.)
  6. Try using standard nylon hardware: there do already exist thousands of different things: screws, pins, nuts, clamps,... These will be much stronger, have a stable size, require almost no post-processing, and in the end be much cheaper. Maybe these will fit, or only require minor changes to your models to fit? In Belgium and the Netherlands, Essentra Components (previously Skiffy) has a good range. But also RS Components, Farnell and lots of others do. https://www.essentracomponents.com/en-nl If you want to print it yourself: - If you print it hor
  7. Older versions of Cura don't allow parts to overlap: if you place them too close together, one will jump away to a safe distance. I don't know how the most recent versions do this, probably the same? Most of the time I place all models into one CAD file, so Cura sees it as one model. For their placement, I use common sense: I place them as close together as practical, so that they won't fuse, and so that I can still grab and wiggle individual parts to remove them. For narrow but high parts (e.g. vertical rods), I make sure the brim overlaps, which gives much more stability against fal
  8. I believe it often has to do with "the shortest distance between the end of the current item, and the next item". So when the nozzle finishes one item, it will search for which next item is closest by from its current position. I think... Correct me if I have this wrong. At least, I found that carefull aligning indeed helps often, but not always, to improve printing order. As Cymon said above, I would also align the long items much compacter, maybe even so close to each other that their brims overlap so they combine into one big brim. Gives less travel time, less leakin
  9. A few years ago there have been discussions among people using ceramic plates or tiles instead of glass? I don't know if that has been developed further, and if it could be a solution?
  10. I doubt if 3D-printed plastic moulds can handle the mechanical load? I have had two-component resin parts shattered and flying all across the room when subjected to a load of only 5kN (500kg). Most injection moulding machines go up to metric tons. You would also need to polish the mould-surfaces quite well to be able to release the parts, removing all layer lines, and you probably still need to use a lot of release spray. But it might work for making chocolat or gummy bears though... :-) If it would be for industrial/prototyping use, what about a cheap aluminum protot
  11. There do exist wrenches that grip on the sides of the nuts, not on the corners: these can be used to remove damaged rounded nuts and bolts. Search for "metrinch". If I remember well, the name comes from the fact that these can be used for both metric and imperial sizes. Anyway, be sure to use two such tools to grab both sides, so you don't apply torque to parts that can not handle it.
  12. Good idea. Such scales should have been moulded-in on each spool, for both 2.85mm and 1.75mm filaments. That could easily have been done.
  13. Heb je alle punten op gr5's checklist al geprobeerd? Die is ergens te vinden op dit forum, maar ik weet niet precies waar. Daarop staan zowat alle mogelijke oorzaken. Ik zou in de eerste plaats denken aan versleten teflon coupler, 3e fan (kleintje achteraan) die niet goed werkt, te dik of slecht filament, te snel of te koud (voor die snelheid) printen. Maar er zijn er nog tientallen.
  14. Indeed, years ago when deciding if and how we were going to step into 3D-modeling and printing, a brand with a good forum was a make-or-break point for us (this in addition of course to other breakpoints like: open filament system, multiple materials, relatively open source, good availability of spare parts, nearby dealer,...). We knew that the learning curve would be high, that we might run into problems, and that we might need expert advice from more experienced users. So before deciding on any printer, I visited the forums first. And I went to see the dealer.
  15. Using two-part moulds will for sure cause the silicone to leak, if it is a slow curing one (>10min). A very fast curing one (<5 minutes) might not leak too much. Unless you fill the seams. Silicone leaks through microscopic pores. A common method to seal the seams, is to use plasticine or wax. But it has to be a plasticine that is compatible with silicone, it should not contain any sulphur (plus a lot of other stuff) which inhibits curing. Do a compatibility test before with a little bit of silicone and the plasticine or wax. You can find good tutorials on Youtube. Search for
  16. I haven't had NGEN warping and coming off the bed, but I haven't printed big items either: mine took maximum 3 hours and were low flat models. PET sometimes did warp if printing on bare glass, in the beginning when I used 100% cooling. Now when using no cooling, it does not warp anymore. But here too, my models are low and flat, and take maximum 3 hours. So, try to print without cooling if the model allows it (=no overhangs, no bridges), or try a good bonding method. I used gr5's bonding method a couple of times (=white wood glue 10% dilluted in water) on models that ne
  17. Before ordering on any website, always check if they have an official address listed on their site (company, street + nr, city,...), phone and email, officially registrated business numbers, etc... And then look it up in an official phone directory, and on Google Maps. If you can see the company logo in the street view on Google Maps, it is probably okay. However, if the company is located on an abandoned garbage pile on Google Maps, better be cautious.
  18. I usually design custom supports, so that I can make sure that I can get in there with a knife, or get in with pliers and hooks to pull out the support. In custom support I can also increase or decrease clearances as desired. Some of my usual examples, in case you need ideas: Various support concepts. The ribs (0.5mm wide, 1mm aparat) on top allow tighter clearances. Orange and pink are supports: they have extensions so I can grab them with a plier, as the model is too tiny to get in with a knife. The brim is for added bonding, due to the large
  19. Maybe you could redesign it so that it somehow latches after attaching, with a sort of snap-fit lock? So it would become a closed circle. That would largely prevent deformations. Almost all plastics will deform under continuous unbalanced load, and especially PLA and light-cured resins.
  20. Usually I also start with a clearance of 0.2mm, and then adjust as trial and error indicates. However this is on a 0.4mm nozzle. As Smithy says, small holes tend to get closed down a bit, and small rods tend to get too big (slightly overextruding). Also layer height has a big influence, as well as the amount of blogs, strings, ringing and other defects. Probably you will need to post-process tiny holes anyway. I always go through them with a drill (see pic): manually, not electrically, because that melts the plastic. The tiny purple things probably won't pri
  21. Yes, sometimes designing the supports takes time. But if that makes the difference between a succesfull or a failed print, or between almost no post-processing or a post-processing nightmare, I think it is worth the effort. I like designing more than post-processing... :-) Concerning the exact dimensions and gaps I would say: design a test piece in which you incorporate several variations, and try which works best for you. For me, the ribs on top work best if ca. 0.5mm wide, with horizontal gaps between 0.5mm and 1mm. Vertical gaps of 0.2...0.4mm usually work well for me. Smaller
  22. Even if you find a material, it is not going to pop up automatically, if printed flat. On the contrary: even if you would pull it up manually, it will tend to snap back into the flat shape as when printed, because that is how the molecules were solidified. You would have to print it in the upright position, and then manually push it down to make it pop up again from itself (if the material is flexible enough to survive this). You could do this by designing a custom support structure that does not consume too much support material.
  23. Maybe like in the old days? Put a paper logbook next to the printer, and for each print, write down username, date, begin and end time, estimated print time (from printer display), meters of used filament, type of filament, etc. And a separate column for total times. This method has worked well for hundreds of years, and is likely to be more stable than electronic means. The data would have to come from the printers anyway, not from Cura. Often a sliced model is printed numerous times. And some others are not printed at all, when changing our mind or improving the model. Cura doesn
  24. For special models and difficult to reach areas, you could model the supports in CAD in the design itself. Then you have full control and you can adjust it to your needs. See these examples for my single nozzle UM2 printers (I have no experience with dual nozzle): A few different support concepts I have used: some with extensions, so I can grab the support with pliers; some with holes to insert pins to pull the support out, some with layers that peel off easily, some with several tiny blocks instead of one big block so I can wiggle each tiny part loose, some with overha
  25. I would suggest you look up some tutorials and demos on Youtube of the most popular free CAD programs. And then see if the workflow appeals to you. For my designs where I have to make frequent adjustments to technical models, DesignSpark Mechanical is good. But it is only suitable for geometric forms, not for organic form. And it is very easy to learn. Not in the list above: if you want to make organic forms, and you don't mind a steep learning curve, then Blender (also free) might be an option.
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