Source
r/cad•
Red_Chairface

[Help] - Can't figure out best way to 'close out' top of lofted surface for a surfboard fin.

Fusion 360

As the title states I am having trouble determining the best method to 'close out' the top of a lofted surface. The current part I am working with is a surfboard fin created by lofting a series of NACA profiles. I am currently using Fusion 360 to make this part but am also fluent in solidworks. This is an issue I have come across a few times now with different parts and decided to reach out for help. Is there a common solution to this problem or a best practice I could follow? Thanks.

here's a link to some screenshots of my part

Posted Aug 8, 2018, 1:06 PM UTC

1612
mooseman99•

In solid works I would create an axis down the center of the top sketch on the loft and do a 180 revolve of half the sketch. Not sure how to translate to fusion.

You could also sketch on the plane perpendicular to your loft planes and loft each half the top sketch to that. That will let you control if you want a sharp edge or not (whether you set your end condition to tangent or...)

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Red_ChairfaceOP•

Thank you, I think this is what I'll end up doing. The tools to perform this in fusion are pretty much identical to those found solidworks. I like the idea of the perpendicular plane sketch.

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mooseman99•

No problem!

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hydethejekyll•

There are a million ways to crack an egg. In the essence of pragmatism, just switch to mesh and bust it out as a new body that you attach to what you have. If you are not familiar in mesh, I could walk you through how to do that

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Red_ChairfaceOP•

I can't say I exactly love using the mesh environment in Fusion - definitely prefer parametric modeling side. I am curious how you would match the interface geometry of the mesh?

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rocketcrash•

Surface fill is your answer in Solidworks.

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Red_ChairfaceOP•

You're right, this is my answer. I don't have a ton of experience in working with surfaces in SW, but I just did a quick test and added some constraint curves which seemed to do what I want. Looks like I'll need to figure out how to do something similar in the mesh environment in Fusion. Thanks!

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bpocketb•

There is the dome feature in SW which could a quick and dirty fix.

Personally I would aim to use a rotated or lofted surface for the very tip. I would loft to create the surface of the rest of the fin body and have a gap between the two to loft across.

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positive_X•

Looks good so far ,
where did you find the NACA profile information ?
..
{ByTheWay , I have had a similar issue "closing" an organic loft and
have not really been satisfied with my own solution .}

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[deleted]•

[removed]

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glucklich21•

Couldn’t just fillet the top edges to match your profile?

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[deleted]•

[removed]

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