What i am doing wrong

[svili 0]

Hello everyone, I hope you're doing well! I need a little help; I'm still a beginner. I want this model to print as it is in the picture, with the inside empty. When I perform a slice, the model gets filled, and an upper layer is added. It slices it as a whole model. Does anyone perhaps know how to fix this? Thank you very much.

[ahoeben 1,968]

In all likelyhood, your model is broken or "non-manifold", which confuses Cura.

 

Try loading the model into 3D Builder (comes with Windows). It will tell you that "One or more models are invalidly defined". Let it repair the model and save it as a new STL.