Hi all. This is not so much a question as a tip i came across.
The general issue is that I have a profile sketch that I want to revolve around an axis. The problem is that the axis I want it to revolve around is not in the plane of the sketch. In my particular case, I wanted a revolved cut of the profile of a door (to make sure it wouldn't hit anything on the frame of the door as it swung) , but the rotation axis of the door was out of the plane of the sketch.
I saw various solutions including this one, but they were only approximations of the solution I was after.
After some experimentation I came up with the following solution.
1. Create a sketch of the profile in whatever plane it needs to be in.
2. Create a separate sketch in a plane perpendicular to the axis of rotation.
3. In the second sketch, create an arc with the centre at the desired axis of rotation. Make the point at one end of the arc pierce a line in your first sketch (or coincident with a point in the original sketch if it happens to coincide with the second sketch plane). Move the other end of the arc to indicate how far to revolve the first sketch.
4. Create a Cut-Sweep (or Extrude-Sweep), using the first sketch as your profile sketch and the second sketch as your path sketch.