Hi PL, if you're still stuck can you also please post a 3DM file with those curves and your current surface result in it instead of only a screenshot?

It helps a lot to answer questions if we're able to analyze the actual geometry and look at it from different angles, zoom in and out, etc... none of which can be done with just a static screenshot.

If your question is about a specific command like sweep it helps if your 3DM file contains only the geometry pertinent to making that specific part of the model and not any other pieces of the model that are not related to your specific question.

- Michael