Unable to Join Sweeped Object

Hello. I am very new to rhino and working on creating a project to 3d print. The problem is, it seems to be solid at the moment on the inside, which I assume means there is some surface that is not connected to another correctly. I looked into trying to join them together and this isn’t working. Any ideas?

How I created it:
created top and base + offset
used sweep2 to connect inside and outside
lofted top + base together
twisted

Thanks!
help.3dm (5.9 MB)

Hi Anna - the top curves are not level

image

Use SetPt, World Z only, and snap to the tops of the vertical curves.

image

Then you can make a PlanarSrf from the two to close up the form - you’ll need to rectrate that from the level curves.

-Pascal

Thank you for the reply. Sorry I am having a little trouble understanding what you mean by the top curves are not level. I went ahead and undid the sweep to double-check, and I can’t seem to replicate what you are seeing (from my understanding its that the star shapes were at different ‘z’ levels?) I updated the file to show each step in case this helps pin point exactly where the issue first occurred. Thank you again I really appreciate it.
help.3dm (7.8 MB)

Hi Anna - if you zoom in you can see that the horozonatal curves are not at the same Z. This last file is less ‘off’ than the first one but still off - I would use SetPt to make certain the top and bottom curves are both coplanar and at the exact same Z as the ends of the verticals.

Bottom curves:
image

Top curves

image

-Pascal