Hello. I have this problem:
Why does this happens and how to fix it?
Why does this happens and how to fix it?
You’ve fallen at the very first hurdle. Try again
In addition to a video which may or may not miss out all the actual useful information we will need, ALWAYS supply a link to your blend file so we can see what you have
Sorry about that. The problem is that some edges are one over onether. The same is for vertices. And how to supply a link?
Attachments
Sorry about that. I do not know how to supply link, so I fixed video.
Upload blend file to http://www.pasteall.org/blend/ and reply with download link
If you have multiple duplicate edges the there is no magic solution, it just means you need to take more care with your modelling in the future. If you duplicate or extrude anything then don’t just cancel the operation, you’ll still have those duplicates, undo it.
Select all vertices and W / Remove doubles will remove duplicate vertices as starting point, but go through what you have and delete what you don’t need or just delete everything and start again
PS Can I somehow delete post #3? It’s my mistake.
I wonder if it would make sense for Blender to actually delete the new vertices when somebody ESCapes to cancel the operation. I’ve done it, then ended up with extra duplicate vertices, just because (at least in Windows), ESC just cancels everything, so you forget that Blender doesn’t. I’ve ended up with mysterious very tiny extra bones as a result of this, too 
In addition to this, is there some way to delete these diagonal edges on sides of train?
http://www.pasteall.org/blend/38893
Thanks, JA12.
If you mean these edges, No. You cannot have faces with holes. What is the problem with them being there ?
What are you going to do with this model. If you export it to another program then that may not even support faces > 4 sides or a game engine which will only support triangles so any benefit in getting rid of these edges will be a waste of time. Even rendering in blender all faces are triangulated at render time so unless you have tris and quads you can end up with unwanted rendering errors if you rely on ngons
I’m planing to export it to Train Simulator, and was thinking to delete these edges because they would increase number of polys. And maximum number of polys for Train Simulator is about 60 000 - 70 000.
No. Maybe you’re confusing the structure you’re trying to model with modeling it badly, or there is a difficulty in understanding the difference between a mesh surface and a real surface (a shell versus solid).
From left:
- This is a plane primitive, it consist of four vertices, four edges, they’re connected and filled to form a quadrilateral face. That face has a direction, also known as face normal, as indicated with a blue line in the screenshot. Where the line is pointing is outside, and the opposite direction is inside. The face thickness is 0.
- This is an approximation of a uncooked but otherwise fine potato. The mesh consist of many connected quadrilateral faces, the whole outside surface is covered with those, and the finished mesh describes an object that is supposed to be solid. Uncooked potatoes are pretty solid. The mesh is manifold because the surface does not have any holes, there is no extra geometry, and consistent face direction of each face tells that the whole surface encloses the solid potato part (inside) and rest of the world with hungry people (outside). If the normals were flipped, it would describe an object where there is air confined in a small volume, and rest of the universe would be a potato
- Again a quadrilateral face with 0 thickness and a direction
- This time it’s used as a part of a surface that describes a solid wall made out of concrete. Same rules apply
But, if you model such way that you have edge/edges connected to more than two faces like the selected face in the screenshot, now you have described a part of a surface that can’t exist. It’s a mesh error called interior face. Could call it a non-manifold edge if you like but that might mix it with another non-manifold mesh error you might come across at some point.
But whatever you call it, the selected vertices/edges/face you’re using to describe a potato is not part of the potato surface. The selected face has 0 thickness and it’s both inside and outside. It’s a mesh error and tools and modifiers don’t know what to make of it when it comes the time to decide which mesh elements are part of the potato, and based on those, which side is inside and which is outside.
My train slowly gain shape. But, please, comment on my errors in model. And JA12, I will delete interior faces.http://www.pasteall.org/blend/38932