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How best to replicate this bowline knot modeled in Rhino?

Question asked by Gan Starling on Jul 7, 2018
Latest reply on Jul 9, 2018 by Gan Starling

In Week 9 of a 12-week course on SolidWorks, for which my chosen project is to design a V-shaped antenna support structure, complete with guy lines. Having a great deal of trouble trying to create a bowline knot for the ends of the guy lines. See Rhino screenshot below of a swept spline.


After many hours of futile effort in SolidWorks 2017, yesterday I made what I needed in Rhino (if only so as to have an example for here). In Rhino I began with a single, multi-knot spline on a 2D plane which looped back upon itself several times (flattened, 2D view of the bowline knot). Then I just lifted/sank various knots above and below the plane in which they first were laid down so as to morph it into 3D. This simple method seems wholly disallowed in SolidWorks for no reason that I can fathom. Certainly no 2D art program I know of disallows it. It's not at all disallowed by Bezier curve math. Yet still I am wanting to create an identical bowline knot in SolidWorks for my project (rather than use my import from Rhino, also attached).

It is proving extremely frustrating having to begin with a multi-knot spline that is not even remotely close to the end result owing entirely to the prohibition on self-intersecting splines. Is there no way to turn that constraint off? Yes, I can daisy-chain plural spines end-to-end, but that only makes for a worse frustration, as tangency cannot be maintained spline-to-spline when needing to move the join-point as the handle angles lock. This latter issue requires that I must first remove the tangency, then move the join point, then re-apply tangency and hope that it simply works out. So I quite gave up on that. I must employ a single, mult-knot spline to avoid that annoyance. Yet SolidWorks forbids such a spline to be laid down so as to loop back upon itself. Where is the setting, please, that allows turning off this annoying constraint? Or lacking that, how best in SolidWorks can I achieve the same result? A tutorial would very much help.

A secondary frustration for me is to do with not having four views (Top, Front, Right & Perspective), as I have always enjoyed in Rhino. Might there be some way to obtain this also inside of SolidWorks? It would very much help in editing 3D splines, particularly when trying to adjust handle angles. With only the single 3D view, over-correction of spline handle angles is more a rule than exception. Alas, and alack.