Solidworks Lofting and Guide Curves

Curious about using guide lines with Lofted Boss/Base

I'm trying to draw a rocket nozzle in SW. These aren't, of course, simple cones, but have a tapered shape.

I start out with circles defining the base and exit.
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Seems like I should be able to define the outer shape of the nozzle using a guide curve...
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But...when I do, it limits the guide to only the portion of the cone directly by it....
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Now, it works fine using Revolved Boss/Base...I'm just curious if there's a way to rotate the Lofted guide lines to define a regular feature. Seems a bit simpler.
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Ron Wanttaja

Hi Ron.
Method 1: Loft a segment of the cone (say 30 deg.) using two identical guide curves. Then circular pattern the segment into the complete cone.
Method 2: Loft the nose cone without the guide curve, while setting the end condition of the larger circle to "Normal to profile".
Method 3: (Not recommended!) Loft two identical guide curves as profiles and use circular segments as guide curves - then circular pattern the body.

The last one is a bit like trying to boil the sea;)

Jeffrey

Make a plane (Plane 2) perpendicular to "Plane 1". Draw a line (could be reference geometry) on Plane 2" that is also perpendicular to "Plane 1" (and on "Plane 2". Draw the OML (Outer Mold Line) curve on "Plane 2" exactly how you want the outside shape of the duct to be. Rotate the OML curve about the first line (reference geometry). Should work.

If you need the duct to be curved, you'll need to start with a curve and not a line.

Hope this helps. "Blue on Top" Ron

To me it seems that you can't make it accurately by lofted or boundary surface. However, besides revolved surface you can use swept surface. Then you can't dimension the circle, but it must be connected with the guide curve.
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