Basic UV unwrapping

Hi, I’m really sorry for asking, as I am sure I’m doing something very stupid and basic, but I have been at this for 12 hours straight and cannot get it to work.

I am building a “fairy cottage” with a “hobbit hole” (round) door. The UV will be editing in Pshop with some complex patterns, so the UV export needs to be clean and proportional.

No matter what I do, the UV mesh comes out in a bizarre fashion.

Here is a short list of things I have tried.

Building the wall:
1 - Boolean cut of mesh/cylinder through flattened cube
1a - bisected version of above, mirrored
1b - remesh modifier of above
2 - Knife project of curve/circle into plane, then extrude.
2a - bisected version of above, mirrored

Applied scale transforms, and NOT applied scale transforms.

UV map:
1 - I have created the UV map before any materials are added, and after a diffuse material is added. I have added a material after the cylinder cut. I have used the Blender and Cycles render engine.

I have recalculated normals inside and out and tried every clean up option. I have reversed all normals, reversed all faces

I have/have not pre-built a cube seam that works before adding the hole, and then I have seamed the hole in dozens of different ways. I have kept the n-gon seams, and deleted the n-gons seams.

I occasionally get a single face to work sensibly, but when I add a second face and unwrap it turns to mush.

If anyone could point me in the right direction I would be hugely grateful. Here is one of my test files and a screenshot of a selected face and the resulting UV map for it.

cubetest.blend (500 KB)

Get rid of the ngons. Convert to tris or quads before unwrapping. You can always use X / Limited Dissolve after you have unwrapped to get back to ngons.

You can also just select the face and use Unwrap / project from view

I tried “project from view”, but it adds perspective, and the image mapping I will be adding need to be exact (Lots of wall-paper, that sort of thing).

I’ve tried the remeshing to quads but only one side worked, the other side was the same chaos. But I will try it again.

I tried “project from view”, but it adds perspective,

Ensure you are in orthographic view and top/front/right/left view etc

Add seams
Triangulate mesh (Ctrl+T) to eliminate ngons
U / Unwrap, set unwrap method to conformal (F6 or in toolshelf for options)
Select all faces and X / limited dissolve to get back to ngons


cubetest (1).blend (517 KB)

The triangulate is what fixed it. I had tried remeshing via a modifier, but I didn’t know the Triangulate command.

I am incredibly grateful for your time, thank you.