Why does Cura remove some parts of my model when slicing?

[Xythos 0]

Hey everyone,

 

Being a rookie in 3D printing, I was wondering why Cura does ignore several parts of my model when I hit the slice button.

 

Here is a picture for more clarity: 

 

My printer is an Anycubic I3 Mega and I tried both the Normal and High preset in Cura. Same result.

 

Any ideas on how to solve this problem? Thanks.

[reibuehl 36]

I would guess that the parts that are removed are too thin or too shallow so that they are below the threshold of what can be printed with your selected nozzle diameter and/or layer height.

To try to verify my theory, you could try to enlarge the model in Cura by 100% and then slice the model again using the same settings as before. If the slicer result looks better/has more details vissible, you could try different slicer settings with the normally sized model. You could cange the layer height to be smaller - maybe even only for the top x layers to minimize printing time. If that is not enough and if your printer supports it, you could switch to a smaller diameter nozzle, e.g. 0.25 mm instead of 0.4 mm.

[P3D 36]

Have you tried the "Print Thin Walls" Option in Cura? As @reibuehl said, the features are probably smaller than your extrusion width. 

[gr5 1,335]

You can either increase the size of the part *or* you can make the "line width" parameter thinner.  For printing very fine detail like this it will come out better if the leaf is printed vertically.  However I don't recommend that because you don't have a flat side and you definitely don't want to print on that stem (it will wobble and quality will suck and it might fall over).

 

[Xythos 0]

Okay thank you guys, these parts were < 0.4 mm that's why they wouldn't show on Cura after being sliced.

 

I've ticked the "print thin walls" box and indeed the thinner parts are now showing regardless of the scaling I use but I'm facing another issue now: when it's supposed to print the thinner parts, it does this (https://streamable.com/txk2o) instead and doesn't print at all (the filament keeps going back and forth and therefore the cold end (stepper motor) doesn't feed the filament to the nozzle).

 

I mean, I've had this stepper motor issue for about a week now, but I thought it wouldn't be a big deal, as it wouldn't occur everytime the printer was functioning. I was wrong.

 

 

Edited July 22, 2019 by Xythos

[gr5 1,335]

Those are called "retractions" and are normal.  If you look carefully you will see that even though the extruder goes backwards and forwards, it slowly proceeds forward.

 

Your issue of "not printing at all" is something else.  Please use some other forum where people who own your same printer can suggest what might be causing your "not printing at all" issue.  If the company that makes your printer doesn't have a forum then try facebook.  There's 100s of forums on facebook.