We are trying to create a surface that fills in a sketch and uses 2 curves to create a domed top. Can anyone tell me how to do it?
Here is a quick sketch of what we are trying to create. The 2 cross sketchs are raised.
I have attached a model of this skeleton. I also attached a STEP file of what we are trying to end up with.
*** Note *** we need it to be a curvature continuous surface.
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Wonderful. Way to keep "continuity" (sorry! 
) PTC........ Too bad, because the second VSS is the one that works best.
Can you go back a couple versions and look at it? I use VSS's for a TON of stuff, because they work so well, and if it no longer works that's going to be a REAL issue.
Wow, it just keeps getting even worse doesn't it?
The tutorial still works. Even though the 1st attempt failed miserably... and reselecting the chains, and redoing the sketch because it blew up, and it did what it was suppose to do (Creo is having a serious problem with mirroring things!)
So I am not sure why it failed on the surface under discussion.
At the top of the bottle, it would allow the line segments to go to zero, but the blends on the edges would not reduce to less that the original sketch... R10 If I changed the filler to R10.1, it failed.
Frank, VSS is still there in Creo Parametric 2.0.
I've just tried to rebuild the sweep feature you've made in Creo 2 and it works well.
And back on topic:
I think this can't be done. I've tried to build the surface using 3 surface patches in Style feature.
This is what isocurves look like in comparison, which is ok, but as the next picture shows.
These 3 surfaces, or each connections in between are only of a tangency connectivity.
Why? Because when you try to switch this connection in Style from Tangency to Curvature, it switches back to Tangency by itself.
The reason is because it would fail if it didn't switch back. Because it's a nonsense to expect, in that particular direction, a linear (degree one) surface connecting to a radial (degree two) surface in curvature continuous manner, as there is only a tangency between the arcs and lines that make the border of this surface.
The sketched curves need to be curvature continuous first in order to create the whole thing as G2 surface, or else the surface as if made G2 by some feature that tweaks it, is never gonna follow these origin sketched curves.
If it doesn't make any sense to you, then try a curvature analysis on the sketched curves.
Ok, here's the latest and last stab at it. The surface is made with a VSS and with the exception of the spine, all the trajectory curves are conics with the rho vale for a perfect 90deg arc (use the sketcher section relation: rho = sqrt(2) - 1). If I used conics in the section of the VSS, it gave some funny artifacts at the curved edge, so the section was an arc driven by the 3 spines. I think this is a LITTLE better, but I think this is also the practical limit to Pro/E without the ISDX package. The grey surface is Pauls first STEP file, the bronze one is my latest. Have fun!
That's beautiful, Frank. I would have never even thought to look for the conics in sketcher Gotta love this forum!
Yeah, I forgot to mention that. The VSS will not vary section, or flat-out fail, if you've got a stationary reference from ANYTHING else. You can ONLY reference the trajectory references in the section.
Happy to help!
What is needed is a flat extrude through the center section with a part that tapers at each end. ID rejected the model that had revolved tangent ends because of the way light reflects off of it.
Frank, I was able to open your attachment. Here is a screenshot of what he wants that explains it better than I can with words.
The top model is the imported from SW and has the continuous curves. What the ID guy wants is the continuous light reflection and not the broken reflection shown in the bottom model.
I never made a statement that I did not have ISDX.
JORGEN LINDQVIST wrote:
In order to have C2 continuity, the basic oblong shape cannot consist of two lines and two arcs.
Where the line meets the arc you will get C2 discontinuity by default. Any resulting surface will also have C2 discontinuity at this point.
the two arcs will have to be to curves with C2 continuity, instead.
This can be achieve by creating curves thru points and setting curvature at the ends.
I think it is a lot easier to create this in ISDX....
Jorgen, there is definitely something behind what you are saying. I created two versions side by side. The left version uses construction curves (line and arc) on which points were located and tangency features on the
ends. On top of this was laid the spline with the ends tangent to ensure continuity. This was done for all 4 sections.
The surface on the right was one with arcs and lines throughout. You could see a small difference in the default surface quality in config.pro but when changed from 3 to 50, the difference was really pronounced.
This is an example of one of the sections... all were done similarly.
Unfortunately, Creo won't let you see the curves well enough to determine how close the spline follows the lines and arcs. But visually, they are round and straight. I know by definition they cannot be.
I think it is working, just not the same. Looking forward to Jakub's version.
This is also in support of Jorgen's observation:
That just confirms that the ID guys just hate perfection
