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The 3-sided surface plague

The 3-sided surface plague

The 3-sided surface plague

Hello all,

I am again running into a problem I've been battling for a long time. I have 3 sides, and I need to create a surface between one edge, and 2 curves.  I need to create a surface between them, but need the surface to be tangent to the edge curve.

Could someone educate me on how to do this?

Aerospace Engineer

RE: The 3-sided surface plague

Here is my attempt at explaining what I think is going on.
I am assumping this is somewhat of a triangular surface and that the lines end in a vertex/point, that is where this explaination goes.

Create a point at the vertex of the two line.
Use Thru Curve Mesh
Pick the Edge as Primary String 1
Next pick Point (Last option) on the Thru Curve Mesh box.
Pick the point created.
Now pick each line at Cross 1 and Cross 2.
Go thru the OK picks until the surface is created. You can either constain the surface while creating it or create it first and then use Edit Parameters and add the contraint there.

If the two lines don't meet at a vertex I have another suggestion.


RE: The 3-sided surface plague


Thanks for the input. I understand your suggestion completely, but I am running into a problem.  The Thru Curve Mesh tool is not letting me select the corner point as a curve.  It will only let me select edges or splines.

I am using NX2.  Am I missing some functionality?

Aerospace Engineer

RE: The 3-sided surface plague

Ohp, never mind. Had to turn on the point selection feature.

Would you mind posting your suggestion if the two lines don't meet at a vertex?  It might help out others looking through this forum.

You also might consider making this a FAQ?

Aerospace Engineer

RE: The 3-sided surface plague

Here is another method that may not be as elegant but is functional: create an oversize sheet that goes though the required points/edges/splines/etc. then trim it to shape.

RE: The 3-sided surface plague

N-sided surface might work out for you, or look into using UG Shape Studio as it has some Studio Surface features that might create some 3 sided sufaces as well as allow you to assign continuity.

Tim Flater
Senior Designer
Enkei America, Inc.

RE: The 3-sided surface plague

Back again.  If the two line don't meet, I create a spline between the two lines and use thru curve mesh.  I then will modify the spline poles to get the required surface.  A good idea is to overbuild the surface and then trim to what you need.


RE: The 3-sided surface plague

Also consider in these situations, that you can trim around the triangle to make a square in simple english. One of the easiest ways is to just put a point at each corner (3 points), then use extract curve/ isoparametric curves, choose the correct points, faces, and U or V (it would be impossible to explain the full process, but with a little tinkering you will quickly understand how to do this). Then from this you probably have enough geometry to brige curves or the like, and then you can trim. Just be sure as you do this that everything is kept clean, and that it wont get you outside your tolerances. This can get you the 4 edges you need for a through curves mesh or whatever you need depending on your situation.


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