Jump to content
Ultimaker Community of 3D Printing Experts

geert_2

Ambassador
  • Content Count

    1,775
  • Joined

  • Last visited

  • Days Won

    24

Everything posted by geert_2

  1. My standard pic to show the effect of a dummy cooling tower (ruler is in mm and cm). In addition to what gr5 said, printing in thin layers, slow and as cool as possible also helps. Also, do not use 100% infill but rather 50% or less. But I could never totally get rid of the effect. At some point the hot nozzle just keeps sitting on top of the tiny model, preventing it from cooling down and solidifying. That is a limitation of this printing method.
  2. A few questions: Are there any soft leather, rubber or cloth straps as interface between the 3D-printed parts and skin, to increase comfort? So that the hard plastic does not continuously rub the skin, causing damage? I have worn safety helmets in the past, and they all had a hard outer shell for protection (obviously), a soft inner plastic frame for good fitting around the head and for shock-absorption, and then a thick, soft leather strap between that soft plastic frame and the skin. Otherwise it was not possible to wear the helmet for a prolonged amount of time, with
  3. At big oil companies, but I don't think it is a good idea to go buying a vat of 160 liter... 🙂 And there are so many different specs for different purposes. I just use hydraulic oil because I had it for my hydraulic machine (and it is on-spec for that hydraulic machine, not necessarily for any other equipment). If I had to buy fresh oil, only for the printer, I would probably go for something close to the official Ultimaker specs: some light machine oil, like used for lubricating bike chains, fine equipment, tools, and similar. You can find that in car-accessories shops, or
  4. I would suggest you add pictures to your post. Then you are more likely to get good answers. You can drag and drop JPG- or PNG-files directly from Windows Explorer into your post while editing. Set the cursor on the desired place, and then drag the picture into there. The reason is that the amount of phishing and hacking has increased a lot since the corona-crisis, so people are less and less willing to open unknown files from people they don't know very well. Without having seen your design (for that reason), my general experience with snap fit things is th
  5. Indeed, I haven't seen this one. :-) Seems like I should bring my knowledge about tools up to date. The inserts I have seen on Youtube videos, but not tried myself yet. If you have used them, do they stick well, and does the molten plastic reflow around the ribs well? I have also seen a similar concept, in which the brass insert had to be screwed into the plastic hole, with a sort of self-tapping one-way screw on its outside, so this would get stuck and stay in there. But again, no personal experience.
  6. I tried tapping too with straight taps (I had never seen those spiraling ones, didn't know they existed), but indeed it didn't work well. Even not when tapping manually and reversing very often: 1/4 turn forward, 1/8 turn backwards. Chips would get stuck and the plastic would melt (even at very low speed, lots of cooling time and lubrication). Also, threads were very weak and got worn-out very soon (M3, M4, M5). So for most of my models, I now use standard nylon M4-screws instead, with a caged nylon nut that can not fall out. This goes a lot faster, and it works better: the thread
  7. Depending on the firmware-version the "Abort" on the UM2 can be plainly visible during printing, or in the "Tune" menu (I have both). In some UM2 there was an issue with driver chips overheating: then they would shut down for a few moments until cooled down, and then continue. Mostly with the Z-axis (up-down). I had this on one printer a few times in hot weather, when doing long print runs. I reduced maximum current a little bit, and since then it never happened again. I am not sure if this could happen to the X- or Y-axis too? But first try the other solutions, and only consider t
  8. I have tried these: - PLA, orange and white: bright colors, printed very nice and smooth, but stuck a little bit less to the glass than Ultimaker or colorFabb PLA when using my "salt method" (=wiping glass with tissue moistened with salt water). Seemed to be slightly less temperature resistant than other PLA. Otherwise no problems. Prints at standard speeds and temps. When burning pieces in a metal spoon on a bunsen-burner, it leaves very little black ash: just a little bit of dry, loose powder that can easily be wiped off. So, the same can be expected in the nozzle.
  9. I think the extra width that you measure might come from ringing- and thickening-effects around corners? When slowing down to take a corner, the nozzle inside pressure does not immediately drop, it lags, so the nozzle extrudes a bit too much compared to the now slower speed. This makes corners thicker. Analog for ringing, sine-wave mechanical oscillations around corners. This could easily explain 0.2mm extra width. Also blobs and overextrusion could explain that, if they would be present. Also, "elephant feet", the sagging of the first layers, could make a model seem wider than it is, if you m
  10. You can always disable all brim in Cura, and design your own in CAD, exactly how and where you want it. I often do this when I want some features to have brim, and others not, or if I need irregular brim.
  11. I would say: start by marking all pulleys, belts, etc. with a marker. And see if they move relatively to each other. Or otherwise, check if the driver-chips don't get too hot (e.g. cooling fan not working, vents blocked), so they do a temporary thermal shutdown, until temp drops again to a safe level. Check if the cables to the steppers are okay, no bad contacts? These are the first things that come to mind, but I don't know your printer, so there could be other issues.
  12. Are you sure that nesting them reduces printing time? Printing the required support material for separation also takes time, and it increases the risk of failures, which also cost time. If you would use two glass plates, and preheat one while the other is printing, so you can switch glasses immediately after completion, it might go faster? Might be worth comparing both?
  13. I would at least try a couple in PLA. I have seen others who made things in PLA for emergency use too, recently. And I have also made prototypes in PLA for single use, to be desinfected with the usual 70% alcohol, or with some sort of chlorine solution (not sure about exact formula). 3D-printed tools are never optimal due to the pores, voids, and irregularities that collect "finger-mud". But this is for all materials, even PET and nylon. So you should make people aware that this is only an emergency solution, and that these pores are the draw-backs of this technology.
  14. Hoi Anders, Do you also have data on *how long* a mask can be weared? Ours were chemical gas masks with filters depending on the industrial chemicals. As soon as the active stuff (e.g. active carbon) in the filter would run out, the filter had to be replaced. This was usually not very long: 30 min ... 1 hour, or so, depending on the filter, the gas concentration and the invironment. But that was 35 years ago, and products and rules may have changed a lot since then. I am particularly wondering on how long a medical mask can be weared before bacteria start to grow wildly
  15. What does it do if you make wall thickness 0.41 or 0.42mm? When making small text, I make the legs 0.5mm wide instead of 0.4mm, to avoid gaps when the STL might make the walls just a little bit thinner than 0.4mm in corners (and cause gaps), due to the triangles. But I am using an older Cura version, so I don't know how the newer versions handle this.
  16. If you want to make videos (=editing, cutting, adding text, effects), a good freeware editor is "Shotcut". This is in heavy development and making fast progress. Almost as powerfull as professional editors, but currently not yet as stable: so you need to save projects regularly [Ctrl S] in case of a crash. It is very easy to learn and handy, and it does not eat too much computer resources. There are a lot of good tutorials on Youtube. Watch them first, to see if it appeals to you. For publishing of course you have all the Youtubes, Vimeos, and others. Just be aware that they may k
  17. Before printing hundreds, print one and carefully test if it really fits and closes well. Cover the front opening (filter opening) with your flat hand, and try breathing: it should be *absolutely impossible* to inhale, and your body should immediately go into panick-mode. However, if you can still inhale with the front opening closed, it leaks sideways, and would not protect well and cause a false sense of security. I have seen too many dust masks (like for painting) that did not work at all. The real gas masks we used in the chemical industry were a lot big
  18. I have seen them on Youtube, maybe your best option is to search for reviews there? Could be on the CNC kitchen channel, or Makersmuse? Or was it that Bernaculus Nerdgasm guy, or something like that? I don't remember...
  19. I would say: make the holes slightly smaller, and drill them out manually with a drill that is still 0.1 or 0.2mm smaller than the desired size. Maybe you could also design a simple 3D-printed retention clip into the case? Try various dimensions on a small test piece first.
  20. For my UM2, I made a nozzle scraper from steel spring wire, after an idea from another user. The very hard inox wire that is also used in dental appliances. In 99% of cases, this works perfectly. Since it is a spring, it moves away when the nozzle moves over it. It doesn't cause any damage.
  21. I also drill out the holes, with this tool. It only costs a couple of euro/dollar in any tool shop. This gives good feeling and control. Do it manually, not electrically, otherwise everything melts (don't ask how I know).
  22. Hope you can read English? To let the model cool and solidify, the head needs to be moved away indeed. But while sitting elsewhere, it should keep printing at the same flow rate, so the material in the nozzle keeps the same temperture and viscosity. So I often print a dummy model next to the real one, that has a complementary shape. So the total printing time per layer is always the same. See the examples below: first the concept, then two parts of real models.
  23. These are nice models, especially the highest one. Here this is called a "castle-villa" ("kasteelvilla" in Dutch). One question: why do most architects and urban designers use white as color for models? Why not more natural colors in various shades like sandstone, warm grey, etc.?
  24. You should make one in which you can insert your smartphone, so it can actually be used. With a slider system. That would be really cool. :-) It might require a bit adaptation of dimensions, but as long as it is immediately recognisable...
×
×
  • Create New...