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Everything posted by geert_2

  1. I don't know the MP Mini either, so this is a *very wild guess*. But to me this looks a bit like you are using a 1.75mm filament in a 2.85mm printer? However, if you would be using the correct filament, I would indeed look for a temperature/cooling problem somewhere in the system, like Nicolinux suggested? Or some piece of tubing or coupler that is missing or mounted incorrectly (similar to the white teflon coupler in Ultimaker printers), which is supposed to contain the molten filament?
  2. I try to simulate that in the design by adding a small rounding. This works somewhat, but is not optimal. The problem is that this approach is not compatible with desired roundings at the bottom. And it gives a bit of deformation of the first two or three layers. So indeed a solution in the slicer to reduce only the outer edge (but not the infill, so we still get good bonding) of the first layer with a user-selectable distance would be very nice. Good idea.
  3. If it is in the gcode, I guess you should be able to see it in Cura when - in layer view - zooming in quite a lot. The "jumps" should be visible. Concerning the "salt method" for bonding, see the full manual (PDF-file) with pics at:https://www.uantwerpen.be/nl/personeel/geert-keteleer/manuals/
  4. Instead of using water to glue them, what about a thin layer of wood glue, or PVA-slurry? First try manually with a few centimeters if that works. Also, you could design your own tool to align and glue these filament ends, print that, and clamp it in a vise or so. Just two simple plates with some 2.9mm diameter indentations, and some alignment features, will do. It would be an interesting experiment.
  5. I have no idea about the shifting, as I have never seen that. I guess you already took a look at the "layer view" in Cura, or in any other slicer, so it is not a defect in the gcode file? Apart from that, you also seem to have "warping" in the corners of the models, so your bonding to the build plate isn't optimal. This could cause the models to come loose during printing. Depending on your preferences, I would suggest you try any of the bonding methods commonly discussed in this forum: dilluted wood glue (1 part glue in 10 parts water, as promoted by user gr5), hair spray (spray it on a tis
  6. I use those left over ends to do atomic pulls at regular intervals. If you would still have more left over, what about heating them with a heat gun and making toys with it for the kids? Arm bands, rings,...
  7. Hey cloakfiend, A good starting point for searching primers might be car paints and primers for plastic parst, like for wheels covers and bumpers: they need to withstand a lot of abuse, sunlight, rain, stones,..., so they need to adhere well to various sorts of plastics (but mostly to ABS, PU, and polyester). For optimal adhesion, they should chemically bite into the plastic and chemically bond, not just cover it.
  8. Maybe you need 6 slots... User neotko has good results with hairspray (spray it on a tissue and wipe the plate). And user gr5 has good results with dilluted wood glue (1 part Elmer's glue in 10 parts water, if I remember well). Still other people use dissolved old PVA-support material from the UM3, thus recycling what would otherwise be waste. My own "salt method" does *not* work for ABS, so no need to try it. However, for PLA and some other materials it can be used. (=Wipe the build plate with a tissue moistened with salt water, until it dries in a thin, almost invisible mist of salt stuck
  9. I would suggest you have a look at DesignSpark Mechanical. This is a limited version of SpaceClaim, and distributed for free by RS Components (big electronics supplier). It only requires registration to activate it. Its user-interface is similar to that of SketchUp, with pulling and pushing on sides or edges of models, to modify them. But it generates good STL-files for 3D-printing. Main disadvantage: import/export module for STEP and IGES standard 3D-formats is optional and not free (actually quite expensive). On Youtube you find a lot of demo- and instruction films. Also on the RS-website
  10. When pushing filament manually through the whole feeding traject, I found the most friction occurs in the teflon coupler and nozzle, when near the end of the spool. Friction in the bowden tube can also be much higher than expected. Also the "unwinding force" is very high: the spool acts as a very strong spring, trying to wind-up the filament again. It is probably the sum of these that causes the problems, when using the original feeder. With the spool normally mounted on the printer, and the filament being fed into the machine, I usually unwind 20cm of PLA, wind it in the opposite direction
  11. To me this looks like underextrusion. If it is only in the left back corner, I would guess it is because the friction of the filament in the bowden tube, teflon coupler and nozzle is higher when bent more in this corner. This especially when printing very hard filament like PLA, and when it is near the end of the spool. Maybe it could also be uneven build plate calibration (too much distance at the left back). This you can visually check when starting a print: is the first line equally thick everywhere? If it was the teflon coupler worn out, or a dirty nozzle, I would guess the problem would
  12. I agree with kmanstudios: heat may be a bigger problem than water (to test water-resistance, I have made a filter for the sink in PLA a year ago: it hasn't rotten away yet). Just don't use water-soluble materials like PVA. In addition to this, the flexibility or lack of it may also be a problem. Heavy clay or sand will deform a flexible mould due to its weight. And a non-flexible mould of course is difficult to remove after casting. But you know that for sure. What about printing the original model (not the mould)? And then make a silicone mould around it, and a plaster or epoxy shell to s
  13. If you have a highly directional microphone, or a modified stethoscope, that might help in locating the exact source. I have a standard medical stethoscope (like those the doctor puts on your breast and back to listen to heart-beat and lungs), but that is not accurate enough. It does not differentiate enough between sounds from various parts. However, car technicians use the same basic stethoscope setup, but they replace the pick-up element with a thin long tube. So in a car engine, they point the tube towards various parts (valves, waterpump, oilpump, alternator,...) and they can locate whi
  14. I highly disagree. Slow travel path for combin moves will cause the drip to increase and unless someone makes a math formula to actually know how much drip/mm/heat/viscosity is lost, you will get a bit of underextrusion when the extruder resumes to print. Hi neotko, From a theoretical viewpoint I do understand your concern. But in my tests, I haven't noticed this problem yet. But I will look out for it in the next prints. Practically, for PLA I usually use the default speeds of 150mm/s travel, and 50mm/s printing, which gives good results. Here, a low traveling speed would have little be
  15. Concerning the new warranty: Yes, I think the wording is now reasonable and much better: first, it is more clear, and second it reflects your "open philosophy" better. Tanks. (Edit: clarified the context of this reply)
  16. If the nozzle uses roller bearings (I don't know for sure), could a broken ball, or some debris that was picked up, cause this sound? In my case, the sound came from this belt rubbing against the flange in the photo, but then on the other side of the printer, left back side, where its home-position is.
  17. On one of my UM2 I had a weird sound coming from the same corner, left back. But it was rather a squeeking sound, like rubber tyres, or like chalk on a blackboard. It was very hard to locate, as it seemed to come from everywhere around that corner. Eventually I found it came from the rubber belt (the one from the stepper motor) sliding agains the flanges of its wheels. Rubbing the side of the belt with silicon grease solved the problem. I used the thick, inert white grease that is also used in microscopes and binoculars, *not* silicon oil, and definitely not petrochemical oils (may damage the
  18. This is what I would rather expect from an atomic pull: see the nice orange one at the bottom. It has still a little bit of white, since I was changing colors from orange to white and back. This is from an UM2 (non-plus) with standard 0.4mm nozzle, 2.85mm filament. On an UM2+ with removable nozzle you might see some additional lines, but the general shape should be similar:
  19. If your model and function allow it (we can't see the inside here), another option might be to cut it in parts, and glue them back together again after printing. Or design some holes for hex nuts and screws, and mount it with screws. This might go a lot faster than other post processing, and might be good enough.
  20. I was about to say that neotko *does* promote hair spray and has a video of it. But he was faster. I use the "salt method": after cleaning the glass plate with water, gently wipe it with a tissue moistened with salt water. Gently keep wiping while it dries into a thin, almost invisible mist of salt stuck to the plate. For me, this gives excellent bonding of colorFabb and Ultimaker PLA, and still good but not perfect bonding of ICE PLA. When hot, it bonds like cyanoacrylate. But when cold, the models come off by themselves and are sitting totally loose on the plate. For the full manua
  21. For some unknown reason, my reply was eaten up by the system and didn't show up on the page. So, let's try again. I use silicon mould release oil: spray it on a tissue and wipe the nozzle. This reduces build-up of molten filament on the outside, but does *not* eliminate it. It depends on the material: it works less or more for PLA, but does not work well for PET, which is much more sticky and "rubbery" when molten. I also tried PTFE oil, which also helps a bit, but less than silicon oil. I haven't tried any other oils. Some time ago, there was a thread in which this was discussed, if
  22. I think it is a good idea to restart from fresh, in case of hard to solve problems. To me, this looks like underextrusion. If the filament is rather hard, as in the case of PLA, and it is bent into a tight corner on the end of the spool, try to manually straighten it. This will give far less friction in the nozzle and coupler. I usually wind it in the opposite direction around a skater wheel of 7cm diameter. Also, I would try the following things: First remove filament and do an atomic pull to clean the path. Then manually insert a piece of filament (with cold nozzle) to see if it slides
  23. XTC-3D is a chemical too. So it may also have health-risks, similar to any other chemical. About XTC-3d, from the Smooth-On website: "Avoid eye and skin contact. Avoid breathing fumes - use in a well ventilated area. NIOSH approved respirator is recommended. Wear safety glasses, long sleeves and rubber gloves to minimize skin contact. This material has a high exotherm (generates heat). Do not mix components in glass or foam containers." The MSDS also mentions that it could cause skin burns. Whatever chemical you use, you need to inform yourself of the risks, and then take proper precausions
  24. In my experience, if the spots are dark brown or black flakes with sharply defined edges, they come from the inside of the nozzle: burnt material from the inner edges of the nozzle, or from around the area where teflon-coupler and nozzle meet. Solution is atomic pulls, and if necessary replace burnt and deformed teflon coupler. If they are bigger and lighter brown spots, without sharply defined edges (more looking like dark honey), they come from the outside of the nozzle: material that has built up around the nozzle, and then slowly burns and leaks down on the print. Especially if you have a
  25. Have you tried a new SD card, or at least cleaned the contacts (blown out with compressed air)? This seems the most logical cause to me. Else, try if all electrical connections on all boards are still okay, not loose. Also those of the mains power supply. Wiggle them. Or maybe spikes in your 230V supply? Flikkering of lamps, motors nearby switching on or off? Electrostatic discharge could also cause stops: I have had that a few times in freezing cold weather: I got shocks whenever I touched anything: doors, lamps, iron tables, lift, just about anything... Also when touching the printer, and
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