Extrude along irregularly shaped closed curve

Is there a command to extrude a planar closed curve along a irregularly shaped closed curve? The irregularly closed curve I want to extrude the curve along is a perfect circle when observed from the front and “undulates” when observed from the right or left.

Hi Zews- sounds like Sweep1 might be it?


I had tried that, and was not successful in achieving the result I am after.

Here are a few screen shots that I hope adequately describe what did not work properly.

I am trying to model a ring that is made out of three parts. A center part and two side parts that fit precisely onto the center part with the help of “steps” in all the parts. The hole through the ring is perfectly round (see front viewport), and the ring is deformed in two directions (see top and right viewports)

Here is a closeup of the perspective viewport with the 3 curves (the cross sections of the three parts of the ring) as well as the rail(s) for the sweep.

This is what it looks like after I sweep the center section.

This is obviously wrong. The right viewport suggests that it is correct, but the top viewport as well as the front viewport show immediately that this is wrong. The “outsides” in the top viewport are at an angle to each other, instead of parallel as in the right viewport (as far as curved lines can be parallel :smile:). I tried several options (like Chain Edges) that are presented for the sweep command. The result is always the same.

What did I do wrong?

I would split the close curve and separate the blue line, make with Sweep2 two surfaces and join then. Maybe this works without split.


I am trying my hardest to understand this, and I have no idea what you are talking about.

Using the curves that Andreas marked with Rail 1 and Rail 2 in a Sweep2 should give you what you want.
At least that’s what I did in the attached.
Ring-Sweep2.3dm (401.9 KB)