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Everything posted by geert_2

  1. For cleaning, don't use soap: that reduces bonding. That could well be the reason for your warping. Or do it the other way round: first soap water (like window cleaner or Mr. Proper), then isopropyl alcohol, and then with pure handwarm tap water only (but no soap). After using alcohol, don't touch the glass anymore on the areas where you are going to print. Finger-grease also reduces bonding. Also very moist and rainy weather might reduce bonding, when printing on bare glass. That is why I started searching for a new method, the salt method.
  2. Indeed. I am a big fan of educating people (although in my case the "clients" are PhD-students and collegues), so that they *understand* what they are doing. Not just verbatim duplication like a parrot, but real understanding, so that they "see it". That sometimes takes hours. And then it saves me days and weeks of time, because next time they can solve it themself, and they can often do it faster than I could (which is very good). Additional benefits are that they become way more happy. And you become more influential, because with each problem-solution you teach them, you also get a better u
  3. I may have missed it in the posts above, but I didn't see what bonding method you used? Could you describe that, thus method-name and exact procedure? That could be a reason too for the warping? Also describe the cleaning method you use for the glass? And the weather conditions in your environment now, temperature and moisture-level? These all play a role too in bonding, in addition to bed-distance and underextrusion. Since it isn't solved, it is best to go over each step again. For underextrusion: on my older UM2 (non-plus), there are a couple of things that are likely
  4. I once measured the bed temp with an infrared gun thermometer: the edges were ca. 5°C cooler than the center of the bed, I guess due to convection that pulls-in cold air from the sides. But below the nozzle-fans, the bed could be up to 15°C cooler than elsewhere, especially on small models where the nozzle kept blowing on the same small spot. Cooling fans are there to cool... So that could cause warping in those spots. Also, on UM2 printers (which have a less powerfull feeder than newer models), the left-back position is more likely to cause underextrusion, and thus poorer adhesion
  5. I am very much pro recycling and pro clean oceans. So it is good that this plastic garbage is collected. But that garbage collected from the oceans is a mix of ABS, PET, PP, HDPE, LDPE, PC, PS, PLA and other stuff. And it is partially broken down by sunlight, eaten by bacteria, contaminated with salt, bacteria, algae, sand, paint, paper labels,etc... There is no way you can make high-quality products from that in an economical way. To sort-out and purify this garbage, you would need to burn maybe 10x more oil than it takes to make new plastic from that oil. So I think t
  6. Technically you can make 3D-prints from photos: I did portraits in that way. However, it won't work well for coins: at best they are going to look like photos from coins, not like real coins. Because one side is getting light and thus highlighted, while the opposite side is in the shadow. So the 3D-print will look very weird, and only resemble a coin-photo if you look through it towards the light. Further, it depends on the material: you need a translucent material that lets light shine through. So, you can print a 3D coin photo from a 2D coin photo. If you
  7. I just stumbled upon this old post. A guy Stefan from CNC-kitchen has made several testing machines himself. See his Youtube channel. But to setup such a machine and correctly interprete the results, you will need some engineering education.
  8. Exactly: standard 0.4mm nozzle, but 0.06mm layer-height. If you print a model in 5x thinner layers, and print 2x slower, it is going to take 10x longer to complete. And if you then need 10x thicker walls to withstand the pressure... My models are very small, so that is still acceptable. But for big models like yours, it is going to take forever. In that case I would consider post-processing, such as chemical smoothing or painting/covering. I recently did a post on chemical smoothing with dichloromethane here, with photos. Or consider painting wit
  9. If it is the sound of the belts rubbing against the flanges of the drive wheels, I handled that with thick silicon grease: I put a little bit of this grease on the edge of that belt. This also is not an official method, but it worked for me. :-) Silicon grease is the thick, sticky white grease used in binoculars and cameras. Never use mineral or synthetic petroleum oil or grease for rubber: it may damage that rubber, and you don't want it spitting oil on the glass bed.
  10. In the mean time, could printing it sideways be an option, if the design has a flat side panel?
  11. Ik maak in mijn ontwerpen in CAD alle lijnen 0.5mm dik, voor een 0.4mm nozzle. Dat werkt ook gemakkelijk op een 0.5mm ontwerpraster. Bij het slicen worden curves nadien vervangen door rechte stukjes: die snijden de bocht af, waardoor de dikte een beetje varieert tussen pakweg 0.48mm en 0.52mm. Als je dan als lijndikte 0.40 genomen had, varieert de dikte na slicen misschien tussen 0.38 en 0.42, en valt alles beneden 0.40mm weg wegens te dun. Ik vermoed dat de lijndikte instellen op 0.35mm tijdens het slicen, zoals hierboven gezegd, ongeveer hetzelfde effect heeft? Maar d
  12. If you have them on a server, you have a chance of getting them back: on most servers there is "shadow copy" software running. When deleting or modifying a file, it keeps a copy of previous versions for up till one year, in a hidden folder. On our systems it is named "~snapshot". A bit similar to the Windows Recycle Bin, but then with different file-versions too, and not so easy to delete as emptying the bin.
  13. Yes. These models were designed a couple of years ago for single-nozzle printers, and older slicers. So they are all printed with the exact same settings. Sometimes I provide gaps to make removal easier, so that parts are only kept in place by strings, not modeled connections. I consider these supports an integral part of the design, not a separate add-on later. Similar to when designing for injection moulding, then you also consider the fabrication method and aspects from the very beginning. These are all very small models, so reachability and removability of the suppo
  14. I often design custom supports in CAD, as part of the model, and then turn the slicer-support off, like gr5 said. Then you have full control. General supports are great for general items. But special models may require special custom solutions. Yes, custom designing them may take quite some time, but you win that back when it prints well and does require less post-processing. For example, see the pink and orange supports in the first pic. This model is too small to get in with a knife or plier to remove standard supports. Now I can easily grab them and wiggle them loose.
  15. If you can't find the official oil, I think a fine oil for light machinery and house-hold stuff should be okay. For example the sort that is used for bikes, tools in the workshop, model trains, etc. As long as it does not dry out into gum, like mine did... But I didn't have a good quality fine oil, and I had 100 liter of hydraulic oil spare, so I gave that a try... Don't use thick oil (thus no grease, no high-temp oil, no car motor oil, etc.), and don't use thin dislodging oil (does not lubricate well). You can feel if the rods are too dry. Switch off the printer, and g
  16. I do it very similarly. First, moisten a tissue with isopropyl alcohol and wipe the rods to clean them: they collect lots of dust. Then moisten a tissue with a drop of oil, and wipe the rods to oil. Never pour oil on the rods directly: it will be way too much, and you don't want oil leaking on the glass, or on the rubber belts. Ultimaker recommends a light machine oil, if I remember well. However, I once had sewing machine oil from a sewing shop, but that dried-out fast and turned into gum. So, now I use thin hydraulic oil, because I have lots of spare of it from our hydraulic test
  17. The companies Materialise, Melotte, and Protolabs do metal 3D-printing. Maybe you can find the info you are looking for at their websites? Including guidelines for dimensioning? I think the models shrink a bit, but I have no experience and knowledge about this myself.
  18. When making tiny filters for a vacuum pump, I had to print them very slowly and in very thin layers. Otherwise, if printed at 0.2 or 0.3mm layers, it had lots of tiny openings, through which tiny jets of water squirted out, similar to out of an injection needle. When printing at 0.06mm layers and 25mm/s in PLA, it was water-tight. But if you are going to print your huge model at such a low speed and layer height, it is going to take forever. So, I would make a *small* test model first, and see how that works under high pressure. Put tap water on it, or even via a high-p
  19. My first thought was: "dirty glass". If you clean it with soap or window cleaner, be sure to clean it again afterwards with pure warm tap water only. Best twice. Thus no more soap. The reason is that soap reduces bonding too. So you really need to remove all traces of soap and detergents. Don't ask how I know this. :-) After a closer look at your photos, it looks like the bottom "sausages" are quite round, not very much squeezed into the glass. That could also reduce bonding. So, in addition to cleaning, I would also check bed leveling, and bring that closer if necessary.
  20. At first, I thought: are you really going to slide downhill in a 3D-printed sled? What if it breaks? But then I saw the dimensions: 12cm. :-) The first photo, it laying upside down, looks really convincing.
  21. Thanks for the feedback, it could indeed help people in similar situations, even for other printers.
  22. Do the walls need to be slanted for cutting cookies? For injection moulding plastics, for sure yes, for casting silicones also yes, unless the models are very thin. But for soft cookies or dough? If I had to print cookie cutters or plasticine cutters, I would probably first try straight walls, print with a standard 0.4mm nozzle (less risk of underextrusion and clogs), 0.8mm thick walls (=2 lines), print slow at 25...30mm/s, thin layers 0.06...0.12mm, and print cool at the lower edge of the temp range. Printing cool helps prevent the filament from decomposing in the nozzle due to th
  23. This looks like severe underextrusion. It could have lots of reasons: user gr5 has made a good list and tutorial video on this. See if you can find it here on the forum (I don't know the links), and check each item on the list. I once made underextrusion tests. Your models look a bit like the 80-90% in my tests. This is PLA. (Lack of light, translucent filament, and narrow depth of field of the camera don't help the photo quality, but you get the idea.)
  24. If you could redesign the overhanging rings to be at 45° or 60°, instead of 0° (where 0° is horizontal and 90° is vertical), they could print without supports. I don't know that machine, so I don't know if these rings are functionally required or not? Or if they could do with a shallower angle? That would seem the best option, if functionally possible, since you don't need supports then. If you do need the rings at 0°, and thus do want supports, but you don't want them to go all the way down, you could also design custom free hanging supports, like I did in these models. But test t
  25. I don't know your printer, but it looks like it still needs calibrating steps, and maybe correcting slack and tolerances. You may need to find manuals and tutorials on that for your printer, or ask the manufacturer. After that, for finding the best settings for general printing: just stay with the printer and watch it closely, while printing small test models. Do lots of test models, one by one. Change speed on the fly, and see how that affects the print quality. Change temperature on the fly, and see what happens. Change cooling on the fly, change flow-rate, etc... Print the same
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