3d curved sweep

[lsrutkowski]

Ok, here's one to make people scratch their heads:

To start off: I am working with Wildfire 4.0 m130, although I do have access to Wildfire 5.0.

I have a "half-pill" shape (90 deg arc -> tanget vertical line -> 90 degree arc, rotated 180 deg, thickened to make a shell surface) with a 45deg conical cut at both ends. The intersection of the conical cut on the end and the flat bottom plane of the rotation is then rounded. I now need to put a protruded shape around the entire edge of this form which is tanget to the bottom/rounded/conical cut surface at all times. This means that I am now trying to stay tanget to a 3-dimensional curved set of surfaces. How do I do this?

I have tried doing a sweep along a trajectory, but I end up with a discontinuity at the bottom face ->round -> conical cut region where the sweep stops remaining tangent.

I have also tried a swept blend with each point along the path defined with the same feature shap and tanget to the surface, but I end up with the same discontinuity problem.

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[MikeMinsterkett]

Can you post a picture of what you're trying to do?

[lsrutkowski]

I am trying to put a protrusion on the outside surface that remains tanget to the narrow, curving surface. The discontinuity occurs at the round.

[MikeMinsterkett]

Did you create this using solid extruding then cutting the material to get the shape you want? I was thinking you could use surfaces then project a curve where you want it then use that as your trajectory. Then you can sweep whatever surface or solid shape you like along that curve. I am invisioning a boat seat where you have the edge that follows the curve.

[MikeMinsterkett]

One more thing I was thinking about. Do you have the STYLE feature? It is where you can do some free form modeling. I use this a lot if I have two points & I want to set my perpendicularities or any other constraints. You could take the curve or copy it then you can set your end constraints to match up with your other surfaces.

[cbernuth-disabl]

Lawrence,

here is what you need to do:

select the edge (surface or solid edge, NO curve!) of your geometry as the trajectory for the variable section sweep.

In the 'References' tab, behind the selected edge you will find the checkboxes X, N, and two checkboxes for T. The two 'T' ones are the two ones you are interested in. If you activate either of these in the sketcher will will see a centerline which is tangent to one of the adjacent surfaces (depending on which box you activated).

If you now constrain your sketch elements to this centerline (by tangentconstraint or 180deg dimension) you are all set.

You will find that this centerline will always keep its tangency to the adjacent surface allowing your sketched line to do the same.

Did not even have to scratch my head