Putting a new edge across a face does not halve the face?

As a beginner, I noticed something when I started to subdivide, reconnect vertices into new edges etc: Faces didn’t follow.

I try to explain this: I hae a spaceship, I started delting som vertices, reconnected them in new ways etc. But sometimes, I did this on an existing face. Say you have a rectangle, I subdivide two of its parallel sides, connect these new two points. But now I did not have a rectangle, made up of two halves of faces … I had the same old big rectangle face with a new edge across it … but that adge did not divide the face as well.

This got very confusing in the end, as I had no clue anymore where my edges were on my dispalyed model and tool slike creating new loops started to behave unexpectedly different.

Is there w sane way to avoid this? Do I always have to delete the face as well when subdividing things and recreate the faces tediously by hand by marking the vertices and using F?

Using F with two vertices on a place creates an edge between those vertices, it doesn’t care about the existing face.
If you want to split the actual face use the knife tool (K) or press J

You can tab into edit mode and use ‘knife’ to cut across faces, or ‘bisect’ to cut across the object. They are in the tool bar on the left. Hit ‘T’ if you don’t see it.

Ah right … found the knife tool … perfect, thank you :slight_smile: Also already got myself a tutorial video about it … great!