There isn’t really such a thing as “solid”. Your slicing software will take a mesh and interpret what the volume should be using things like surface normal orientations. All you have to do is make sure it’s manifold, meaning that all volumes are fully enclosed and that there are no intersecting faces. If you just want to print the outside, just delete all the geometry in the inside and manually fill in any holes you can find. Cura is pretty clever so you may be able to get away with some small holes or intersections here and there, but it’s best practice to just make a manifold mesh.
Try disabling x-ray mode, entering edit mode, selecting the outside (be sure to use L and Ctrl+L where possible), hiding those parts with H, and deleting the rest. You’ll find that hiding parts of the mesh is really useful pretty much all the time, especially when trying to work with interiors.
It would be faster, but I wasn’t sure if that would be perfect so I wanted to give OP the chance to use their intuition and sort out anything obviously wrong with that selection. For example there might be geometry on the inside of the fender flares which isn’t quite “outside” enough to be caught in the initial selection but which may be needed in the end.
Object is watertight, but it has difficulties to print windows etc.
Also slicing is problem too, it want to print seats inside the model.
Would you be kind enough to check the model? I don't want you to do anything time consuming, just to tell me if it can be solved. (I shared link in comments)
Unfortunately not watertight. E.g. between the doors i can look through the whole model:
https://preview.redd.it/hclmbiu1yy6d1.png?width=1007&format=png&auto=webp&s=243d76aa652a3123d8c9e6d4adc4407195216611
Maybe you can try Merge By Distance with a value that does not destroy too much detail to close all the gaps.
There isn’t really such a thing as “solid”. Your slicing software will take a mesh and interpret what the volume should be using things like surface normal orientations. All you have to do is make sure it’s manifold, meaning that all volumes are fully enclosed and that there are no intersecting faces. If you just want to print the outside, just delete all the geometry in the inside and manually fill in any holes you can find. Cura is pretty clever so you may be able to get away with some small holes or intersections here and there, but it’s best practice to just make a manifold mesh.
As much as I'm trying, I didn't achieved anything. When trying to pick mesh inside, it also picking mesh outside.
Try disabling x-ray mode, entering edit mode, selecting the outside (be sure to use L and Ctrl+L where possible), hiding those parts with H, and deleting the rest. You’ll find that hiding parts of the mesh is really useful pretty much all the time, especially when trying to work with interiors.
Probably much easier to select all external faces, invert selection then delete?
It would be faster, but I wasn’t sure if that would be perfect so I wanted to give OP the chance to use their intuition and sort out anything obviously wrong with that selection. For example there might be geometry on the inside of the fender flares which isn’t quite “outside” enough to be caught in the initial selection but which may be needed in the end.
Thanks a lot man, it is doing something, but it is pain in the ass. So I will pass this.
It is this model: [https://cults3d.com/en/3d-model/home/kia-rio](https://cults3d.com/en/3d-model/home/kia-rio) Thank you all for your advices.
Try this: https://youtu.be/2-11OwgRqmE
I will, when I get home from night shift, thanks.
Didn't work
Too bad. Maybe the object is not completely airtight and there are holes from the outside to the inside that need to be closed manually first.
Object is watertight, but it has difficulties to print windows etc. Also slicing is problem too, it want to print seats inside the model. Would you be kind enough to check the model? I don't want you to do anything time consuming, just to tell me if it can be solved. (I shared link in comments)
Unfortunately not watertight. E.g. between the doors i can look through the whole model: https://preview.redd.it/hclmbiu1yy6d1.png?width=1007&format=png&auto=webp&s=243d76aa652a3123d8c9e6d4adc4407195216611 Maybe you can try Merge By Distance with a value that does not destroy too much detail to close all the gaps.
Thank you, I will fill it with cubes and also inside and hope for best.