Help with intersecting a tube into a wall

[broneeandreas]

Hi guys. 

I want to create a tunnel going from a poly-plane without booleaning. I tried 8 times with different ways but they always end op being a topology mess. What is the best way to achieve this, I posted a screenshot to further explain what I am trying to. 

Thanks

[damaggio]

You could start with a cilynder and a cube , booleans could be used here too and a bit of cleaning up, tunnels like these are always fun, specially texturing and lighting.

[broneeandreas]

Ty for the answer. I tried this, but it wont let me bevel the edge, it says it has an non-manifold vertex. I posted a picture of the mesh.

[damaggio]

it is not marked where you want to bevel.

You should not have that poly plane down below, you can delete that and have the floor be a separate piece.

Models are not made from a single piece, is just like real life construction .

[broneeandreas]

So, so should I great a new polygon cube and merge its vertix, or simply let it float? 

[damaggio]

Here's a simple example, all could be made out of the cylinder, no booleans needed anytime soon, from the cylinder corners you can extrude other walls or simply have them modeled separately, the cylinder can be bent with a deformer.

The floor is a separate piece, can also be bent .

[broneeandreas]

Not sure if I understand, but I already tried with the method of just going with the cylinder, but when I extrude the outside faces, I am left with a hole from the faces inside the cylinder. 

[broneeandreas]

Ah, I think I get it now, I just made a quick one from your idea, however, do i maintain the inside of the cylinder when extruding the faces outwards?

[damaggio]

You created more problems now because you lost the inner circle walls...here's another way of doing it...

[broneeandreas]

I see, but how would you integrate the floors then? 

[broneeandreas]

When I flatten the bottom, it ends up like this. 

[damaggio]

You have to use a another cylinder as a reference so you maintain the right curvature.

Place another cylinder on top and match by looking thru orthographic.

[broneeandreas]

Placing the cylinder so it matches the hole exactly, and then adjusting the vertex?

[damaggio]

Yes, you got it.