Modeling question

Been taking a crack at this Solidworks thing (learning new 4 letter words)...and have a question. Have lots of CAD background...a dozen flavors of AutoCAD, IntelliCAD, Sketchup, and the money maker for the last 13 years TEKLA structures. All that to say this, SW is a different animal altogether. They literally threw all forms of "usual practice" out the window lol. So starting from scratch. I'm really just trying to get some flat patterns to generate DXF files to get GCODE from for a CNC router...Most of the fuselage could be (I already have...) drawn in 2D CAD and get the patterns easily. But apparently I'm a glutton for punishment and was going to try to model the curved parts...i.e. turtledeck and wing/tail skins. So I had some success on the lower fuselage skins...tapered box lofted from two sketches, turned to sheet metal, and can manipulate the result...i.e. unfold to a pattern. The turtledeck...not so much... sketched parabolic curves, try to create a loft between them and get various error messages. Ironically it "previews" the loft exactly like I want it, but when I click the green arrow it has a fit. Have watched more tutorials than I care to admit but haven't had an "ahHA!" moment yet. Figured this should be a common modeled part so thought I'd ask here. Picture attached.Attachment 6008

I haven't been using SWx all that long but think I have basic lofts figured out...which took lots of effort and frustration. It looks like you're trying to make a solid loft with an open loop. For a solid part you need to close it at the bottom of each station drawing. Or you could leave it as an open loop as drawn, loft it as a surface, then thicken it. There are some very experienced guys on this forum though...Mark

If you're trying to loft a solid you may have to use a closed profile as Mark says. You could get your 2D patterns by first lofting a surface instead of a solid, then create intersection curves on your planes which would be the intersection of the sketch plane and the surface you created.

Or if you need a station profile you can modify (eg, in a complex curved part), add them by right clicking on your surface, select "add loft section" then select the plane. You'll get a profile with a few points you can move (delete some of them to make it smoother). This came in handy modeling cowling surfaces where I needed to adjust the profile a bit in the middle of the loft and splines weren't cutting it.
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Originally Posted by Mark Meredith

I haven't been using SWx all that long but think I have basic lofts figured out...which took lots of effort and frustration. It looks like you're trying to make a solid loft with an open loop. For a solid part you need to close it at the bottom of each station drawing. Or you could leave it as an open loop as drawn, loft it as a surface, then thicken it. There are some very experienced guys on this forum though...Mark

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Got the error message about using ALL closed or ALL open...tried to go back and edit the sketches. Watched a few tutorials and tried various things for a good hour and couldn't "add" a line entity across the bottom of the parabolic curves. I guess I'm relating these SW "sketches" to an AutoCAD (or every other CAD program I know of) "polyline", which can be added on to, cut, etc... am I assuming something dumb again? ;-)


So how would I "add" the line across the bottom of the arc or draw half of an ellipse from scratch?

There are no 'polylines' in SWx. I'm not sure why you can't add a line, can you post an example file we can play with?