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BrolY September 19, 2011 03:43

Non manifold boundary error
My project is a kind of sphere. To block that geometry, I creat the blocking for only a quarter of the geometry, then I extrude the faces of the blocking with the option "extrude blocks along a curve".

At the boundary faces, I have tis minor error which occurs all the time : "non-manifold boundary at node xx" (xx represents all the nodes on the boundary face) and the extrude fails. I had the same errors when I try to create an o-grid at the 2 blocks which are at the junction of the 2 boundary faces of the blocking.

Does anyone know where this error comes from, and how to fix/avoid it ?


PSYMN September 20, 2011 12:49

Sorry, I guess I don't understand how you extrude to capture a sphere... Maybe some images would help me understand what is going wrong here and how to fix it...

But for definitions... A manifold node is one that is surrounded by a single loop of nodes. A non-manifold node is one that is surrounded by more than one loop of nodes...

BrolY September 21, 2011 04:06

1 Attachment(s)
There is an hole in the middle of the sphere, and there are also holes between the sphere and the middle hole (look at the attached picture for a better understanding ;))

So I created a blocking for a quater of this sphere, and use the function "extrude along a curve" to block the other parts of the sphere. But sometimes, this function didn't work because of "the non manifold boundary at node xx".
I finally succeeded in extruding the blocking by creating curves instead of using the sphere curves.

PSYMN September 21, 2011 09:20

I still don't get it... I would probably have used a quarter Ogrid (like in the sphere cube tutorial), but I am glad you figured out a way that worked for you.

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