Welcome to the Onshape forum! Ask questions and join in the discussions about everything Onshape.
First time visiting? Here are some places to start:- Looking for a certain topic? Check out the categories filter or use Search (upper right).
- Need support? Ask a question to our Community Support category.
- Please submit support tickets for bugs but you can request improvements in the Product Feedback category.
- Be respectful, on topic and if you see a problem, Flag it.
If you would like to contact our Community Manager personally, feel free to send a private message or an email.
How can I make this panel match this curvature?

https://cad.onshape.com/documents/c2d08122b7071e78ddef2ecc/w/c85ee399eb656c77a356c89b/e/6099882c0de00cccbf126294?renderMode=0&uiState=6854bf46da6bb33b3c0baa01
0
Answers
You will need a possibly 'overbuilt' reference face, created off profile and guide curves in the U and V direction of this object. See "Loft" in the learning section for further information. Then, you can project your sketch curve onto that surface and get the desired 3D curves.
Constrained surface makes this a freak'n breeze. Man I wish I had that tool 9 months ago. Wasn't sure what your design intent was. I just made a piece that was offset down a smidge from the top and inset into the opening.
No need for profiles, guide curves, tangencies, end conditions, paths, etc.
Note: learning the surfacing tools does help with this sort of thing to understand what is happening. and making edits easier.
See @EvanReese 's videos and custom features.