How to control sketch start points when lofting through curves or through curve mesh

[tallard]

When using through curves or through curve mesh is there a way to align the start points of sketches or curves.
I find that when we are lofting using sketches or curves if there are different numbers of elements in the sections or if the start points of the curves are not aligned properly you get a twisted, ugly surface as a result.
Any tips would be appreciated.
We are running NX7 64 on Win 7.
TIA,
Tim.

 

[tallard]

Here is an example image of the trouble we are having ...

 

[tallard]

I have done some searching in this forum and have found a number of other related posts. The point alignment is ok but is not available if using through curve mesh. I think probably the best option here might be to only construct 1/2 of the "tube" at a time instead of having each section closed.

 

[JohnRBaker]

For your example I would just use a simple Surface Through Curves since you have so many cross sections that the additional 'cross curves' needed for a Surface Through Curve Mesh are not going to add much additional shape information and may in fact result in a less than smooth transition. And so if you do use the Surface Through Curves you can then use the Points method as well as several other 'Alignment' schemes, none of which are available with Surface Through Curve Mesh since in that case the system is depending on the explicit parameterization of both the primary and cross curves for the alignment which as you've already learned is not giving you the results that you want. Therefore, with a model like you've shown, I would avoid Surface Through Curve Mesh and stick to the more flexible and controllable Surface Through Curves or even a Swept Surface if there was a single trajectory, or centerline, curve to follow.

John R. Baker, P.E.
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Siemens PLM Software Inc.
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Cypress, CA
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[tallard]

Thanks John.