Cura leaves gaps in wall cylinders

[devleon 0]

I'm slicing a model for a case I designed in Fusion 360. Exported as STL at the high setting.
The model looks fine in the solid view, but when I slice (0.4mm layer height and line width), cura leaves these weird gaps in the circles everywhere. 
The cylinders have a ID of 4mm and a OD of 7mm. Why is this happening? How to fix?

[Smithy 671]

Check if you have Coasting enabled in Cura - if so turn it off.

[devleon 0]

I did have coasting enabled, that all makes sense now. Thanks.

[Smithy 671]

But you can try coasting, I just said turn it off to be sure it is coasting which causes the gap in layer view. Coasting stops extrusion right before the layer is finished and the rest is printed with the remaining pressure in the nozzle. So it basically a good feature, but it is not working for all objects, so you have to give it a try if you want.

[ungutknut 2]

In case this didn't got solved - I noticed something weird: You say you've set layer height + width to 0,4. I think this isn't going to work well (assuming you're printing with a 0,4mm nozzle). The layer height should be max. 50-75% of the nozzle diameter.

[devleon 0]

12 minutes ago, ungutknut said:

In case this didn't got solved - I noticed something weird: You say you've set layer height + width to 0,4. I think this isn't going to work well (assuming you're printing with a 0,4mm nozzle). The layer height should be max. 50-75% of the nozzle diameter.

Oops, my fault. I meant 0.2mm layer height and 0.4mm layer width. And while I already printed this correctly, I reprinted it with slic3r, which did a much better job of filling the thin walls correctly in the other parts of the model. I had a wall that was 1.2mm thick, and cura decided to print 1 perimeter and then use tiny zig-zag infill which resulted in 4 more hours to print and a crazy shaking printer (see second picture). Slic3r simply printed 3 lines as expected.

Edited February 14, 2019 by devleon

[ungutknut 2]

Ok, good to know. Funny fact: I'm also currently trying to switch from cura to slic3r due to a different issue (cura leaving gaps in shell).

[dhansen1988 0]

Hey tldr but I can tell you that the gap is the result of the z seam. Your z seam alignment is probably set to anything BUT random. If the z seam location doesn't change then it'll show up as a long vertical gap in most things. Set z seam location to random and it should sort itself out.