Seam marked, but not unwrapping like the marked seam??

Hello, after hours of struggle and searching on the web, and also even making the entire 3D model over again for almost 3 times hoping I did something wrong, but nothing works.

If I mark the seams, and then use U and unwrap to UV, it’s not the same as I marked them. Like one field is split in 3 fields.

Down here you can see that I’ve selected the area on the right side that I have seamed and the left side the UV panel.
Selected area is one field and in the UV it is split in 3 fields.
It’s like the program also doesn’t care where I’ve seamed, because places I have not seamed in will stick to fields I have seamed, and parts that I have seamed, will split. Confused
Why is this happening and how can I fix this?

Thanks
File: http://db.tt/Ob26W3By

Image1:



Image 2:

Please always attach or post a link to your blend file, your screenshot gives way way too little useful information. All I can see on the right is just a tiny portion of the seams, so the unwrap may be perfectly correct given the seams you have placed or something else.

little hard to always add the file, but here it is, link posted above and here : http://db.tt/Ob26W3By

The fix will be very easy for you. Select the verts in each of those 3 pieces and remove doubles. The mesh has been separated into those parts you’re seeing. Use Select Non Manifold in vert select mode to see edges which haven’t been merged back together.

You shouldn’t be splitting your meshes to created edges between smooth and flat shading. I suspect that’s where you’re getting hung up. Try that out and report back if you have more problems.

After I selected shading - smooth, I went to object modifiers - add modifier - Edge split. because cylinders and other edges became really ugly after only using shading - smooth. Is there any other way?

You can do that, but do not apply the modifier. If you leave it, unwrapping will progress as normal. Use it as a visual tool if you like, but know that it ultimately breaks apart your mesh. Be weary.

Ok thank you, removing the doubles fixed it I think.