Strange shape when deleting faces I am currently working on Blender Guru's Chair Modelling Tutorial.
When I delete the top faces to make a hard edge, the face on the front starts making a weird shape.
Anyone knows why? Couldn't find it out myself.
Thanks in advance,
Tobi
he subdivision surface modifier is placed before the mirror. Invert them.

The reason: if before, subdivision surface will smooth vertices out of the mirror axis, so they won't join anymore.