3dnerd

Hi, I think I have the same problem, but did not knew about this thread. I opened a new one: http://umforum.ultimaker.com/index.php?/topic/10299-top-surface-not-closed/ and dirkdirk (thanks) pointed me to this thread. I read now all 19 pages - phew! I want to try also with the fan, but I don't know hot to switch off the fan only for the top layers. Is there any setting in Cura? And is this problem really solved now? Is Ultimaker working behind the scenes for a solution? Maybe Cura update that switches off the fan for the top layers automatically? What about the 'solution' with the front left head skrew?

Hi, from my very 1st print with the UM2 (which is now 6 weeks ago) up to now I see in my print results small thin gaps between the filament paths of the very top layer. Take a look here: You can see dark lines between the filament paths. On the right side it is much better. I checked different parts I printed and there is almost every time an area where paths to not fuse together smoothly and show these very thin gaps. I used different materials already, but almost same problem. Bed is levelled and I get a homogenous 1st layer. Here the settings I used for the part on the photo: Material: Innofil PLA green, printed at 230° - Layer height 0.15 mm - Shell thickness 1.2 mm - Bottom/Top thickness 0.9 mm - Fill density 25% - Initial layer thickness: 0.2 mm - Travel speed 150 mm/s - Bottom layer speed 20 mm/s - Infill speed 80 mm/s - Top/bottom speed 30 mm/s - Outer shell speed 20 mm/s - Inner shell speed 20 mm/s So what I have to tweak to get the top surface more smooth and closed? Thanks!

Ok this explanation I can understand. But honestly, if I get an UM2 and have to tweak temperature and speed settings and now also turn off the fan I doubt that this is 'normal'. My UM2 is only a few weeks old. What I expect from UM2 is insert filament, tell UM2 which one I have, use 'Fast print' settings in Cura and start printing. Is it normal that I have such problems?

Is there any setting in Cura I can switch off the fan for the top layer? And again, I still do not understand if the coupler is deformed inside why it can cause the gaps and/or the not closed top layer. Can you explain that?

What I did now is to increase the temperature of the nozzle from 220° to 230° and used following settings: - Layer height 0.15 mm - Shell thickness 1.2 mm - Fill density 26% - Initial layer thickness: 0.2 mm - Travel speed 150 mm/s - Bottom layer speed 20 mm/s - Infill speed 80 mm/s - Top/bottom speed 30 mm/s - Outer shell speed 20 mm/s - Inner shell speed 20 mm/s This seems to improve it a lot as shown here: As you can see the perimeter has no gaps anymore. So higher temperature solved this problem almost. But the top layer is not closed smoothly. On the left side you can see single passes of filament on the right side the top layer is closed as expected. What is the reason that on the left side the top layer is not closed? How can I correct this now?

Regarding adhesion, if I set 1st layer height to 0.3 mm and the filament noodle has 0.4 mm diameter then the noodle gets 'only' squished by 0.1mm to get a layer height of 0.3 mm. But if I use 0.2 mm for first layer then the noodle gets squished for 0.2 mm which presses the noodle better into the glass bed. This is what I think. And the result shows I get better adhesion with 0.2 mm instead with 0.3 mm for first layer thickness. The filament tip looks like this, after changing: Could you explain what you mean saying my coupler has a small cove? A simple drawing would be nice. And how could this cove cause the perimeter not connect?

Less distance? This I already have now with my 0.2 mm first layer - or not? Could you please explain what do you think could be wrong with my coupler that it causes such problems?

Hi dirkdirk, can you explain what is so important to print with 0.3 instead of 0.2 for first layer? I get good results for first layer with 0.2 mm now. And the 1st layer is not my problem, only in the upper layers the perimeters do not touch.

Hi dirkdirk, I printed now with your settings, except initial layer height. I used 0.2 instead 0.3 because otherwise I could not get good bed adhesion. The print results with your settings is shown here: The initial layer was very smooth, all paths of perimeter and infill melted together very nicely. The photo shows the print status after 4 layers of the bottom. Now it printed two perimeters. The gap is now between the outer and inner shell. Also the infill of the bottom layers do not melt together anymore, you can see single paths instead of a solid, smooth surface. What now?

Hi IRobertI, > With a shell thickness of 1mm you will cause cura to tell the printer to do two passes of 0.5mm. Are you sure? If I look at the 'layer view' (see post #5) I see a red outer perimeter and a green inner perimeter which has double width of the red one. IMHO this means Cura creates 3 passes - can you confirm? What I wonder is that 1.0mm shell thickness is what Cura sets in his 'Fast print'. So this was not a decision by me, it was a default setting of Cura! I started with 'Fast print' and switched to 'Expert settings' there you can see 'Shell thickness' was set to 1.0 mm by Cura. It shows also the yellow background with this hint 'Shell thickness should be a multiple of nozzle size) UM2 drives three perimeter passes as you can see in the image posted in #9. (click on that image then you get a detailed zoomed view) If I take a closer look myself maybe there is no gap between infill and perimeter but a gap between the 2nd and 3rd pass of perimeter? See illustration here: If yes - how it comes? How to get rid of it?

Hi, @dirkdirk: The main thing you changed is the shell thickness from 1.0 to 0.8. But what does that mean? Does it mean I cannot create a wall thickness of 1.0 or 1.2 mm? I cannot belive it!?! > ...PTFE coupler is dead What does 'dead' mean? How can I check if it is dead? @Macua85: I tested bed levelling with a squared part which almost occupies the whole print bed. I have good adhesion everywhere, so bed is levelled quite well. I wonder that the first layer of the green circle (first picture) is almost perfect but the square close to it not since there is this gap between the outer and 1st inner paths of perimeter. And secondly I wonder that there is this CLEAR THIN thin gap between the perimeter and infill - where does this clear gap coming from? The nozzle size is 0.4 mm, shell thickness 1.0 this means to me UM2 drives three paths and they overlap a little bit. But it seems not? I still need some help...

Hi, I did some further tests with different shapes, same settings mentioned in the 1st post of this thread. Both is PLA from Innofil3D, printed at 220°. But still same issue: (click on the image to see it in full resolution) In the top image you can see how it looks like after the 1st layer was printed. The perimeter is 'far' away from the infill. But only for the square, the circle looks OK at this point. I tried also with different filament (the green one is PLA, Innofil) and used shell thicknees 1.2 mm and 1.0 mm (1.0mm is what Cura used in 'Fast print'). But no difference :sad:. The infill paths touch each other and melt together, this you can see in the circled parts. Only in the bottom green part you can see single paths of the infill. But in all images again this clear 'cut' between infill and perimeter. I really want to know what is the reason for that. BTW the prints were stopped at different layers, so they don't show the final result. I just stopped printing once I detected the error again. I also took away the printed parts during 'hot' printbed, so some parts are warped only because of that. Thanks for any further help...

Hi, @gr5: I think it is this one: https://www.youmagine.com/designs/ultimaker-2-fan-mount-dual--2 But in the comments of this design Ultibrain says: The problem with this design is it reflects the air towards the heater block, and in facts disturbs the temperature/PID process. Lowering the fan speed is indeed a way to decrease this effect. However now I use a modified design, which has a closed bottom, this works way better! In the mean time Ultimaker came up with a less critical firmware, this firmware now just continues. But for all reading this: be aware this design not only cools down the print, but also cools down the nozzle...

Hi, here a screenshot of all my options: (Click on the image to see it in full resultion) As I told in my 1st message I used 'Fast print' and then switched to 'Expert'. So Cura overtook all settings from fast print then I changed only: - Shell thickness from 1 to 1.2 - Bottom/Top thickness form 0.6 to 1.2 - Fill density from 10 to 35 - Speed from 50 to 35 The objects where printed 'All at once'. I used Innofil3D filament violet. If I look at the 10mm circle I printed for testing it looks quite nice. There is no gap at all between perimeter and infill. But this one causes problems - I don't really understand.

Hi TinkerGnome, this is what Cura layer view shows: I did not test with Shell thicknes 1.0 yet since Cura shows this hint that shell thickness should be a multiple of nozzle size, and I think the Ultimaker team has a reason doing so - or not? But I wonder that the 'Fast print' option uses a default shell thickness of 1.0 mm by default and at the same time Cura shows this hint that it should be a multiple of nozzle size!?! Either the default setting sould be 1.2 (as a multiple of nozzle size) or Cura should not show that yellow hint - both together is very confusing... But the question is still, why I get this gap between infill and perimeter and how to get rid of it?

Hi dirkdirk, If I give some pressure to the belts with my fingers they feel very strong, so I don't know if this is the reason. I doubt that I can get them stronger if I loose the skrews, press down the motor and fix the skrews again. Here two other pictures, done with an USB microscope, may someone can judge better: (click on the image to see it in full resolution) IMHO it looks like if the diameter of the filament is too small for some reason between the infill and the perimeter. I wonder that there is this clear gap almost same size around the whole part. I did a test print as you can see in the upper image. There everything looks fine. It shows the 2nd layer of a 10mm circle with 10 lines of brim. I used the maintenance function 'Move material' and pushed out a few cm of filament. Then I measured the diameter, it is always between 0.35 and 0.45 mm. Maybe I have to tweak some settings in Cura?

Dear all, I finished a printjob again, but wonder why the inflil and perimeter is not touching. It looks like the perimeter is not really fused with the infill: (click on the image to see it in full resolution) Just that you get the correct imagination of the size, the vertical tubes have a height of 20mm and diameter of 6 mm Nozzle size: Stock nozzle 0.4 mm Material: Inofill3D violet, printed at 220° Cura settings: I used the 'Fast print' from quickprint menu, then switched to 'Full settings' and set: - Shell thickness from 1 to 1.2 (since the yellow background and the hint told me that the shell thickness is not a multiple of the nozzle size) - Bottom/Top thickness form 0.6 to 1.2 - Speed from 50 to 35 What is the reason for that? How to get a better connection between infill and perimeter?

Hi Yellowshark, thanks, just to make it clear, my posted Cura images show: top pic: Cura 'normal' view middle pic: Layer No. 17 (of total 40layers), the last layer below the solid layers (of the base plate) start bottom pic: Layer No. 18, the first layer of the solid layers (of the base plate) The upper small wall is not extruded into the base. The part was extruded from the bottom 'L' shape. Then on the top face of that L I started another extrusion for the small top wall. There is no pic from underneath. The upper phot is taken when UM2 did the last solid layer of the bottom part (layer 20). The lower photo is the finished result similar to the Cura top picture I posted.

Hi, I ordered the fan Labern mentioned. I will mount it in if it arrives and let you know the result...

Hi TinkerGnome, this one I also considered. But on the one which came with my UM2 I can see the 'I' (capital letter i) on the right side of the SDHC symbol. This 'I' is the symbol for UHS-I Bus Interface. And I don't know if UHS-I is necessary or not. Or if Class 4 is more important. I am just not sure what to take since the same as mine I cannot find on the net.

Hi dirdirk, thanks, yes I can do that. But I want to know why Cura does not create a solid, closed surface and on top of it the small vertical wall. Instead it creates a gap inside the surface - this takes longer and gives worse result as one can see. I want to know if this is a slicing problem or if I can change my model somehow that this happens no more.

Hi, I have a problem with a part I created and printed. This is how it looks like in Cura: And this is the printed result: I printed Innofil PLA at 230° with following settings: - Nozzle size 0.4 - Layer height 0.2 - Shell thickness 0.8 - Bottom / top thickness 0.6 - Fill density 10% - Print speed 50 mm/s As you can see in the Cura images the upper face where the inner small wall sits on is interrupted where the small wall starts. The lower Cura image shows the 1st of three layers, there you can clearly see the small gap lines where the vertical wall sits. Why Cura interrups the surface instead of creating a closed one? I wish to have a closed face consisting of three layers and on top of this the small vertical wall should start. But as you can see it is not. How can I get a closed surface before the small top wall starts to get printed? In the photos of the print result you can see the gaps in the upper layer where the small wall starts. If the layer would be printed as closed surface then this problem won't come up. How can I correct this and get a closed surface where the small vertical wall is printed on? Thanks...

Dear all, I want to buy some additional SD cards for my UM2, but I'm not quite sure which one I should take. The original one is a Sandisk, 4GB, SDHC, Class 4, UHS I. But if I google for such specs I cannot find any, seems 4GB cards are no popular anymore. I only find some with higher class (typically class 10) or without UHS I. So what is important? - UHS I? - Class 4? Can I also take 8 GB or 16 GB cards since they are more popular? Thanks for any help!

Hi Nick S, thanks, I already though something like this, but a timer is not the best choice. Maybe someone can develop a switch-off circuit which recognizes the bed coming down after print and interrupts the power...

@Amedee: ahhh thanks :wink: @nallath: I need something to send gcodes to UM2, therefor I asked the 2nd question in my post: 2nd question: Is it possible to send a gcode to UM2 using Cura (15.02.1). If it is not possible using Cura then I need an alternative such as pronterface, even if it is not officially supported.