Surface detection / Top layer problem

[duisenberg 0]

Recently I printed a plate with Cura2.3.1 and ran into something strange:

The main print settings are 0.04 layer, 0.8 shell with 0.4 nozzle, 0.4 top/bottom, 25% infill. The printer is no UM, its a clone with prusa kinematics running marlin firmware.

The print started well, but the intermediate layer is messed up and top layer as well. Quite similar to the otherwise mentiones "pillow" effect, so at first I thought I bummerd with some of the 2.3.1 settings. So I started 15.04 and got this:

I tried with all reasonable settings, thicker top/bottom but the effect always stays the same - the top layer is not recognized, its just the infill and the print will have the same issue as with 2.3.1

Then I remembered there came a Cura 14.07 from the Chinese Company DGO on SD card. I never tried that one because ... well outdated, isnt it? But ok - installing it costs a minute, settings set and got this:

The top layer is looking as it shall look, also the last black layer, the shell is well connected and going down it shows all 10 top layers looking like the last one. I am quite sure it will come out without any pillow-like effect since the layer representation always reflected the print quite accurate.

So the big question here is what is the DGO version of Cura14 doing different and why does it detect the top layers correctly where Cura15 as well as Cura2.3.1 bummer.

If the STL helps - I know its quite a stupid logo, but seems to hit the issue quite well - here it is:

LogoPlate

My guess ist that with 15 somewhere a flaw has been picked up that prevented the correct recognition of top layers. It seems that in 15 switching from Combine A to Combine B (which wont work with the model at all) at least seems to detect the base top layer (the last black one) correct but then thinks the top layer thingy is done. Or maybe the DGO guys ironed something out, I didnt test a generic 14.07.

Edited November 13, 2016 by Guest

[IRobertI 516]

This is from 2.3 with default PLA settings, 0.4 nozzle, normal quality. Looks normal to me?

Also, just a general comment. Printing this thing with 0.04mm layers is huge overkill IMHO and only wastes a ton of time for very little gain in quality.

[duisenberg 0]

Yep, long print. Intentionally, not mutually. Not for the sake of the model but for testing the material at thin layer printout.

This is how the model came out with the DGO cura. To lazy to swap colors. Still not really done since I forgot to set infill from 20 to 25% but quite noticeable difference.

In 2.3 layer view the missing top layers indeed are displayed. But well, what came out then doesnt look like having a top layer on the letters. Maybe not that wysiwyg as one should assume.

There are ways to manually, by plugin or by settings work around the issues, sure, less speed, more flow.

But maybe there also is some kind of flaw in the slicer that calculates some percent to few flow and to few bridges for small layers, round down issue or conversion,  such a thing, currently my best guess.

Hmm, the dropfiles expire too fast. Sorry, need to look for another space to up them.

Edited November 14, 2016 by Guest