Trying to join\merge two objects

I am trying to merge two objects so that where they both overlap each other new edges\faces are created that are smaller sub divisions of the original edges\faces. What is bizarre is that I was able to do this by selecting 2 objects in object mode and then press CTRL+J. But now I can’t. This image shows a face that should be subdivided by a Join but is not https://imgur.com/koYXR32

What is bizarre is that I was able to do this by selecting 2 objects in object mode and then press CTRL+J.
No you were’nt.
Ctrl+J just joins two objects into one object. It does not create any additional vertices/edges/faces

Ok then how would I not only join two objects into one object entity but also have new vertices\edges\created where the two objects overlap each other.

I have found a way to use a 2nd object as a cutting tool using the Boolean modifier which is cleaner than merging two objects.

hi
I have 2 objects


i want merge and join this 2 Object by face
IMPOSSIBLE !!!, I had all try, Cgrl-J, Crl-P, Snap, Union,…
anythink work
Thank you for your help
SySpheres

Too little info, image is also cropped which takes away a lot of useful information.

Is your mesh two objects or is it one object with separated geometry?

The boolean modifier will not work properly for non manifold objects (not solid), nor will it join properly 2 objects that do not overlap in some way.

Even if you solidify your “open” - non manifold boxes and overlap them so that the boolean modifier works you would have to manually clean up the topology after applying it.

Your best bet is to join the meshes (Ctrl J) and then in edit mode manually add edge loops slide them into place with the vertex snap option and then merge double verts.

After joining the objects add these edge loops:


Then merge these vertices:

Note that you will still end up with a non manifold mesh that will be no good for smooth shading.
Edit: If you want to make the boxes manifold you should model them something like this. (I also joined them together with the manual method that I described earlier, in this case you also have to delete the faces that are “inside” the joint.)


If you add a bevel modifier to it you will be able to smooth shade this one.

1 Like

Hi DNorman
I have 2 independent objects
OK, thanks for your example
i will test.

Best regards