Hi. Trying to learn my way around loft function. I’ve created a bunch of sketches for a basic boat hull with two closed profiles and some guides. Lofting appears to go well. Then if I try and shell from the top surface the top sketch gets in the way. So I hide all the sketches in a folder. Finally I can shell the top surface. The shell happens but I get a odd wavy line inside the hull!? Can anyone shed some light on why the wavy line isn’t smooth as expected?
I scaled the design up thinking because the dimensions are small it would change the wavy line. It didn’t.
Here’s the file if anyone would like to inspect it.
Training-boat-hull-loft-to-shell-inside-wavy-line.shapr (138.3 KB)
Can’t tell you why is this happened but can tell you how to workaround the issue. Just make a negative shell.
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If we had curve analysis tool we would probably see that curve crunches inward in an awkward way.
Also your 3 sketch the way you drew will not naturally connect to a point, so my recommendation would be continue your sketch to meet at a point.
If you have problem SHELL try split it in half and shell and mirror.
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I can’t explain this issue from a mathematical point of view, but I feel it in my gut — the problem is that the bow of the boat is only 4 mm wide, and when we apply a 2 mm shell, there’s simply no room left to form a proper shape. If you scale it up, the shell works just fine.
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Yes I see what you’re saying. Very interesting. I am just learning and was intrigued to see it buckle in the curve.
I’ll draw it again with some larger dimensions and see how it goes. I want to try multiple profile lofting so thought I’d start with a boat hull with a profile at the front end instead of a point.
If you want more control because you want adjust the profile fitspline might be the better option for the profile curves.
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