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Showing content with the highest reputation on 11/15/2016 in all areas

  1. Look at the flair of the user you dissed. Look at mine. Look at yours. The etiquette of this board is not like 4chan. The standard here is to comment as if you are face to face. Many of us do meet with each other at conferences and maker faires. I'll give you the benefit of the doubt that you would not say "Never made use of Google in your life?" to someone you were talking to for the first time at a conference. Also, user/ultiarjan 's statement, notwithstanding the existence of combination bearings, is correct. The Ultimaker design uses bushings for XY. Combination bearings instead of bushings would be both overkill and a design problem. Given that the movement rod diameter is 8mm, a bearing outer diameter would be ~15mm, rather than the existing bushing outer diameter of 11mm. This would require a redesign of the slider blocks and more clearance inside the case.
    2 points
  2. Hi Folks, As I’ve been testing the hubbed MK8 feeder wheel for some time as it was assumed to be better than the knurled feeder wheel that’s used on the Ultimaker 3D family, I’d simply had to try this type of feeder wheel and here is my findings. It is important to note this test is done with a MK8 feeder wheel only, having an effective diameter of approx. 7 mm. This test is done with the feeder wheel driving on the inside of the filaments “memorized curve” when rolled out from the filament roll. Using the inside of this curve drastically reduce the friction between the filament and the bowden tube when printing using high pressure. The first thing I observed is that the hubbed feeder wheel needed much more torque than the knurled feeder wheel to feed the filament. This is caused by the fact that the small radial “knifes” have to cut across the filament and leave a track line that is notable wider than the track line from the knurled feeder wheel. What is also counting here is that the distance between the “hubbing” (the radial knifes) that is only 0.6 mm apart, versus the distance between each small squared “pyramid” on the knurled wheel that is approx. 1 mm apart each other. So the knurled wheel make a punched track that is smaller and has a wider grip to the filament. This explain why hubbed feeder wheel needs more torque than knurled feeder wheel! I’ve made a picture of the hubbed wheel track here: Between the every lines the distance is 0.5 mm. (Taken with an USB microscope.) The above picture is the track line from the MK8 during high load printing first layer. Here you see that the compression and stepper slip can lead to a double track, kind of slicing, but no separation. This slicing reduce the grab on the feeder and lead to grinding.. Here’s a pictures of a grind part of a filament when using hubbed wheel: As in the previous picture; 0.5 mm between the lines. I’ll have to mention that the print finished without any issue.. I also made same print with a knurled feeder wheel and made a picture with the two feeders at same place during a printing of exactly the same print object. OK., I’m using a stepper that’s geared 1:2 for both test. The truth is, the knurled wheel could extrude without any slippage, but the hubbed wheel could not. But mind you, this hubbed wheel type also grind during “lots” of retraction under high load! As you see, the knurled wheel also makes a little more rough looking track during load, but do not slip the filament or grind it. I did this three times with same result, not very scientific but have some indication of a practical result. This show clearly to me why Ultimaker still go for this type of feeder wheel! Here is another interesting thing to see, this is that you can adjust the position of the knurled wheel and the pressure on it in order to have a better grip! And finally, the knurled wheel is sure better for the softer type of filament.. Here’s a macro picture of the two feeder wheels. This picture is taken after I removed the hubbed feeder and put back the knurled feeder wheel type to the printer. You’d see the remains of some PLA in between the “knifes” on the hubbed wheel. It is important to note that this subjective test only made on the MK8 feeder wheel with 7 mm effective diameter. This makes the radius for this wheel only to be 3.5 mm and with this small radius the knifes dig “kind of” hard into the filament! Other types of hubbed feeder wheel with larger diameter do not dig this much into filament, but need more torque during feed as more knife’s is to be forced into the filament when rotating. But for this particular comparison, the knurled feeder wheel is a winner in this case! .. - .. So, a little breath from my side, I’d see lots of you folks still using the “old” feeder with feeding the filament on the outside of the “normal” filament curve (Ultimaker standard). As the filament is rolled off and cut to proper length in order to have as lo friction as possible, or to put the roll on the side on a chair to obtain the same.. A loose few turns of the rolls make less friction for sure and a roll lying on the side create less friction as the filament rotate during feeding. But with a feeder unit mounted so the that the feeder wheel is driving the filament on the inside of the loop is so much better that you NEVER again have to do this anymore. This procedure is as follows; 1) Turn your feeder unit around, so that the reverse side become the front, the pressure adjustment will on the inner side of the printer. Oh yes, -hold the feeder stepper motor when loosening the last screw or it will drop down inside.. :( There is a good description of how to do this in the manual. 2) Use the firmware for the Ultimaker 2+, this will change the rotation of the stepper for the feeder. 3) Adjust the E-step pr/mm to same value as before, or requested. 4) Any correction that’s needed due to different heath block, standard Olsson or anything else. There might be something else, but I’ll assume someone may chime in for correction here. Sorry folks, but I had to mention this. Wish you all a happy 3D printing. Thanks. Torgeir.
    1 point
  3. Try printing at half speed. Quality just sky rockets at 20 to 25mm/sec. And make sure ALL printin gspeeds are the same - none of this "infill faster" stuff. Fast travel speed is good but slow printing speed.
    1 point
  4. Hi Thomllama, could you share a screenshot of what settings you have enabled for retraction? Does this happen all the time, or just with this specific model? It can be that your mesh has a lot of vertices at some locations in your mesh. As a quick fix, you could run it through an online repair tool and see if that changes anything. Good luck!
    1 point
  5. I've been using S3D with my UM3 from the first day I got it Really nice results so far. There's several profiles posted on this forum that work, and also some on the simplify3d forum.
    1 point
  6. thanks for tip about the tension adjustment! reading more of the manual now. And I manage to get the nozzle unclog it was very easy Doing some new prints now.
    1 point
  7. I've had the same concern with UM3 not recognizing that the material flow setting has been set above or below 100% in Cura. When checking Tune>Extruder (x)>Material Flow during a print, it's always 100% and not what I set in Cura. I had asked support at fbrc8 about this a few weeks back and was told they are checking into it and would let me know about this issue as soon as Ultimaker lets them know about it and the latest I heard when I asked again was that they are still looking into it. So it's now nice to know, until this gets fixed, to set the flow % at 100% in Cura, then adjust it in the UM3. I also have a concern that when I adjust the material flow % for one Extruder, it also sets that same material flow % for the other Extruder - i.e., currently the UM3 does not allow independent flow settings for each Extruder. I also asked support at fbrc8 about this and was told: "Unfortunately the inability to set the flow setting independently is a design choice from Ultimaker." I would appreciate a clarification on this and why this is a "design choice" from Ultimaker. If I want a flow setting of 104% for Extruder 1 and 100% for Extruder 2, why is it the UM3 cannot do this?
    1 point
  8. Got 2 UM3's in the closet with a thick dampening blanket covering the door. 2x 15 hour prints came out perfect. Now finishing a 40+ hour long print, which i checked an hour ago, and was perfect. So i think that solves the issue :)And i get a bit more peace and quiet Somua tank (French WWII tank) was the test print: Edit: Does PVA play nice with colorfabb PLA/PHA?
    1 point
  9. So I finally did it - I made a thorough video about how to keep your parts from warping and how to keep them from coming off the bed during a print. Please give it a like on youtube!
    1 point
  10. c'est dû au fait que les aimants dans le moteur perdent de leur propriété magnétique quand ils chauffent. Et donc du coup le moteur perd du couple et les pas peuvent sauter. Et il faut faire attention car passé une certaine t° ça peux être irréversible.
    1 point
  11. Lets get back to topic Google has some answers http://forums.reprap.org/read.php?1,242758 https://m.reddit.com/r/Reprap/comments/2cr3sa/linear_ball_bearings_vs_bronze_bushings_vs_igus/ Also this is very interesting http://dabbletron.com/bearings-vs-bushings/ The main difference is how efficiently they work changing positions rapidly without giving friction (that could increase ringing or force the motors to push harder) Anyhow as long as they are good, almost anything can 'work' but ideally atm linear bearings on the head work better.
    1 point
  12. Hi Folks, As I recently removed the MK8 feeder wheel from my printer, cause it did not improve at all over the knurled wheel. I'd just want to inform anyone interested in this modification about this matter. For more info about this, see this tread: https://ultimaker.com/en/community/33367-knurled-feeder-wheel-versus-hubbed-mk8-feeder-wheel-for-filament-drive Thanks. Torgeir.
    1 point
  13. If the slicing time incresed too much, maybe you can activate the auto slice deactivatable feature... :-)
    1 point
  14. I bet on UM2 two years ago, the machine was great for some points but had numerous issues, you guys from the team already know and already heard about them so many times that is useless to repeat (also this forum is full of cases). To have the promised machine with the + extension i had to wait 2 years and would had spent 500 more € (2800 total), so i would not use UM2+ upgrade for comparison. Let skip also the UM2 double extrusion part, that was another reason me and other 10000 users buiyed the machine. Old, boring story. What i would like to see from you, perhaps i am missing something, is a more clear communication about UM3, clear case studies, more real example of prints, not coming out from marketing offices, without waiting users to do it, that would be a reason for me to bet again on UM. Productive part: UM3 is working well with nylon, which is truly intresting, do you have some pictures of a Nylon print with supports? No warping? this might be not true since there are examples of e3d scaffold supporting e3d edge printed with the dual feed. Correct me if i am wrong. Not the same range of options, of course, but not even just color. I am here to be convinced, not for the love of debate . This have to be clear thank you all
    1 point
  15. so he is lying to you that's for sure the nozzle wouldn't block it after an hour. first of all, if the price is right, buy it. nothing much can go wrong with these printers. just look for exterior damage.. how many printing hour does it have? below 2000 basically means it is as good as new.. look at any exterior damage , are there cracks? are the belts ok? they should be tight. move the head around, does it move around smoothly? if not, put a little bit of sewing machine oil on it (take that with you!) and move the head again. then i would say a used UM2 is worth between 800 and 1000 euros depends on the hours it has ran.. the problem he is describing is the PTFE piece.. that will clog up your prints.. just buy the thing as cheap as possible, buy the upgrade kit for 400, it will have a new feeder, new head assembly and this will solve all those issues.. that way you have a basically almost brand new um2+ for about 1200 to 1400 euros.
    1 point
  16. Think your part has a big footprint so you don't need to use a brim at al imho .. If you'r worried about sharp corners lifting you can also make small "ears" on it in CAD, so you have less material to remove, like this;
    1 point
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