Nicely merging different extrusions

Question

I made this teapot:

_{HDR "03-19_Night_B" CC BY-ND 4.0 | Scratch Texture CC BY-NC 2.0}

Offending geometry here:

How can I make where the spout touches the teapot body bevel nicely so that the teapot body smoothly merges into the spout, rather than the spout simply popping out of it. Any suggestions?

Blend file

Answer 1

In this case the solidify and the subsurf modifier don't really contribute to the problem, and the texture on the surface is also incidental (ie, not relevant).

The main issue is really the abrupt 'non-transition' between the spout and the body. In your case because the object is Lathe-able geometry (you either used a screw modifier or the Spin tool) you could redo the body with more steps to have finer grained geometry for matching up.

You had a considerable difference in the size of polygons between the body and the spout and that makes it difficult to match up nicely, this image shows a better match between polygon sizes.

Getting the two patches of mesh to match up in a way that would make the merge smooth is not a trivial thing in a polygon modelling tool like Blender. Getting them to approach the same subdivision level is a firs step, but is no guarantee that the end result will be acceptable for close up renders. Regardless it is worth trying.

Blender has all kinds of tools to help you model intricate details

• 'Vertex Slide'. Shift+V, allows you to move a vertex along any connected edge.

• 'Knife Project' tool to cut shapes into meshes. Here i've cut the profile of the spout into the Body of the pot to prepare the attempt to merge. (the blue outline of the cutter-mesh is just a Draw Over to help distinguish the meshes involved, it's not part of the tool..)

  if you look carefully, this shows the first sign of something we don't want to see. Ngons.

Now you have two problems, how do you match them up?

As soon as you see hideous geometry like this, you know you are going to have a bad time.

Even a bevel here will still give unfavourable results, but it may be one realistic way to get an acceptable transition. Adding an EdgeSplit modifier or Subsurf modifier on-top can smooth it out enough to be acceptable for everything except close-ups.

There are entire tools/software dedicated to dealing with mesh intersections like this. (Groboto, MeshMixer..to name just a few) (sorry more to come, hence i'm adding this as community wiki I encourage additional editing)

Answer 2

I would do this way: First of all create a hole in your teapot, Alt Right click on an edge of the hole and read in the up right infos the number of vertices selected.

Then, still in edit mode, create a circle with the same amount of vertices. Alt right click to select the whole circle, Shift Alt right click to select all the vertexes of the hole, Ctrl E "Bridge edge loop" to connect the circle with the teapot. Then extrude, scale, move to complete the mesh as desired.

Answer 3

You can use two methods (that I can think) merge objects and modify the mess manually.

For the merge objects you need to separate the objects and the use the boolean modify with the union operator. But it will have a strange topology after it's applied.

The way I recommend is to work with the mesh manually.

1. First delete the teapot faces:

2. Then make faces more or less like squares, select edges, that you can select more than 4 at the same time, and press F. Note: it could be better if you first tried to make the main mesh having the same density of the second mesh (subdivide the main mesh) but this will require a lot more work as you will need to create more topology.

3. Then you can work with this mesh to adjust more the edges.