Modeling help

[BHOoi]

Hi, this is a help I need. I have been trying to model the surface shown in the pic below in Creo2 but without any luck. I attached here the 3D file in IGES format for your reference. Thanks in advance for yr help.

[dgschaefer]

That looks like fun. I really can't spend time on it right now, though.

Reminds me a bit of that Molteni Arc Table that someone posted a while ago:

I tried to find that thread, but the forum search failed me.  It also had 3 up and 3 down features.  If you can find the thread, there may be some good ideas there.

There was also an 6 way union challenge that might give you some help, if you can find it.  Again, search has failed me (or perhaps I've failed in providing the search tool with the right words), but attached is my example.  It might have some ideas that you can use.  It uses an N-sided patch.

[dgschaefer]

Found the 6 way union thread:

Does anybody know how to create this model ?

[BHOoi]

Thanks, I will go through the thread.

[dgschaefer]

Finally found the Arc table discussion.  It was within another thread, it starts here:

Re: So, they want me to learn SolidQuirks.....

[BHOoi]

nice.... this will be a good reference for what I want to do. Thanks

[StephenW]

Modeling creatures of the oceans??

[dgschaefer]

It seems your IGS file doesn't match your image.

[BHOoi]

ooops... i uploaded the wrong file. Should be this one. Sorry!

[BHOoi]

Thanks for the trick. Didn't know warp can do this kind of wonder.

[BHOoi]

just for fun... probably as a surface modeling exercise for me.

[psobejko]

Here's my try.  Not very close, but it is parametric:

(Creo 3.0 model attached)

[TomD.inPDX]

It is a spherical equation but not quite sinusoidal.  It almost looks like a semicircular curve.

The IGES file is not spherical.  It was created with Rhyno so it is something that was sculpted.

In order to copy this part close to the original, you can try making a trace curve and save that.

Now you can use the evalgraph() function to drive your own curve within a part.

Trace curves are done with mechanisms and assemblies.  Very useful tool for reverse engineering.

[pnos]

[BHOoi]

I did a bit of read up about the enneper surfaces and learned that apparently Rhino has a plug-in module that contains enneper surfaces in its library.

[BHOoi]

Nice, I will try it myself

[BHOoi]

OK, after many trials this is what i have got. I failed to get C2 continuity between patches and i am sure some of you may help to get me there ..... I attached creo 2 file here for your reference.

[BHOoi]

[jsparber]

By Gosh,

    This is what is known as a 'Saddle Curve.'

    It has a mini-max inflection point in the middle.

    Your app possibly needs to be informed of that inflection point first, before you try to model this particular figure.

   The good news is that there is only one inflection point.

Y/t  Old Math Major, Joshua H. Sparber, -

[BHOoi]

Thanks. With more tweaks to the construction curves, this is the best I can achieve....

[BHOoi]

getting better at it ....