[help] join two differant faces

hello, I’m new to blender.
I like to modeling a bottle with square bottle body and round bottleneck.
after I modeling tow part of them, I have no idea to join them.
please give me advice.

Well it is really only possible to bridge two loops if they have the same number loop vertices, but basically you do this (in object mode).

  1. Select the bottle. Hold shift, select the cap.
  2. CTRL-J to join the two objects into one object
  3. Tab into edit mode
  4. Select the top loop of the bottle, alt- right click the top loop.
  5. Hold down shift, hold down alt, and right click the bottom loop on the cap. Both loops should be selected.
  6. let go of the keys. Press w->looptools->bridge.

Sometimes bridge has problems with choosing the correct verts to fill, and you might need to do a couple by hand. Good luck with your gin bottle. To fill a face, select 4 verts and press ‘f’

Actually that’s not strictly true anymore, but I recommend only attempting to bridge two loops if they have the same number of vertices. You can bridge uneven loops, but you’ll get triangles, and that’s best avoided. Try to make sure they do have the same number of vertices.

As an alternative to the loop tool addon and its bridging function, you can now use the built-in Bridge tool (no addon needed i mean) from CTRL+E -> Bridge Edge Loops (or Mesh -> Edge -> Bridge Edge Loops) and press F6 to edit the function the way you need.
It’s able to bridge uneven loops too, but as K. Horseman , be prepared for triangles

Excellent points from Horseman and Sanctuary on uneven loops. I use it so much I kind of forget that looptools is an add-on. And as it always seems to be a thorn in the punchbowl, I go to great lengths to keep most models all quads.

Heh, I skimmed so quickly I didn’t even realize you were suggesting LoopTools. I thought you were suggesting what Sanctuary suggests. :spin:

Delete bottle body.
Bottleneck: Add lowest circular loop to vertex group and add Cast modifier (use vertex group,Cast type=Cuboid, x=on:y=on:z=off,factor=1)
Add lowest circular loop to vertex group and add Shrinkwrap modifier (use vertex group,mode=project, negative=on,positive=on,target=Cube). Add cube and position it middle of your circular loop.

So you do have square, apply modifier and extrude down.

thank you all for advising, I try Bridge Edge Loops and get nice result.

This is another result by method form TynkaTopi, and I think it is better then result 1.
Thanks, again.

I miss a step at the beginning : lowest circular loop, I add whole bottleneck to vertex group.
And this is finale result that i want.

As a new user of Blender you might want to stop thinking in terms of modeling separate elements while planning to join them later, and start thinking in terms of starting at one end and extruding bit by bit until you get the shape you want at the other end. Bridging is a powerful tool, but the fact is that your bottle is a simple object - a rectangular prism with one end squeezed into roundness, or a cylinder with a large part of it flattened into faces - that should have its starting mesh modeled simply and then edited to the degree you want… Just for future reference!