Thanks for the reply Michael. MoI definitely requires a new way of thinking, which is very challenging! I didn't know about slicing with a curve like that--very useful!

Here's the spout from the side, where you can get an idea of what I'm talking about:



At the opening, the side surface I'm trying to model is essentially vertical, and very slightly convex (if you looked at it from above). Conversely, where the spout is attached to the wall, the surface has become cylindrical. To me, there doesn't appear to be an obvious base shape to use that could then be carved away with booleans or trimming, which is why I was assembling part by part (after having no luck with sweeps, lofts or networks...). It seemed like such an easy project when I began!

See if you like this one... I made it with your curves.

One limitation of MoI is that it doesn't have surface continuity options when creating patches or network surfaces.
If I was making this in Solidworks, I would do what Burr has done but cut away the surface at the top and re-patch it with a curvature continuous surface.

Perfect--just what I was hoping to see. How did you accomplish it?

I swept the back profile to the outlet profile (I had to modify the outlet profile to get a good sweep) with the 2 bottom rails... Then I took the curve from that original little top cutout you had made, and used to to boolean away the top (as Michael had just showed you... You can extract the edge of that cutout piece and flatten it in the top view with the edit frame, then extend the ends to be beyong the new swept surface) Then I deleted the flat surface from the boolean difference and created 2 segments of that inner edge to run a blend command on.. So that top piece is G2 curvature.. I could do this with the bottom piece too, but left it as it was because you had drawn it that way and figured you might want it to be shaped like that..

If this is too hard to follow, I could do some screen grabs for you..

Hi Steve.. The spout I posted is G2.. In my last post, I stated that it was only the top, but pretty sure it is the top and bottom piece also... FYI.

Hi pelanglo, ok I see what you mean now - sorry I had misinterpreted what you wrote earlier and I somehow thought you were talking about some kind of custom elaborate water catcher thing coming down from the spout.

So yeah something like that where there is more of a gradual continuous change from one shape to another probably won't really work with just one simple boolean, you will need to do either sweeps or networks to form the surfaces in that case.

But working on a shape that has no strong 2D profile element to it means that your project isn't really leveraging the greatest strengths of NURBS modeling as compared to polygon/sub-d modeling.

As a model becomes more sort of amorphous or all melty looking in shape, those are actually the kinds of shapes that polygon/sub-d modeling can work really well for.

You can still do such things with NURBS, but you will be working with a more advanced and harder to learn toolset area of doing a bunch of freeform surfacing with 3D curve networks.

Models where you're able to leverage 2D curves and booleans for producing your model is really where NURBS modeling greatly excels when compared to polygon/sub-d modeling.

Shapes like you want to do here are kind of a bit in a gray area, not really driven by 2D profiles very much but also not so fully organic like a human face or something like that either.

- Michael

So if you want to see it, you can open the file I posted and delete these 2 surfaces here:



After you delete them, look from the right side view and notice it is just a cutout of a sweep, like michael posted..

Then run the blend command on the 2 opposing edges from the top, then the bottom pieces.. Adjust, rinse and lather...

Thank you both for the *extremely* useful replies--it's particularly helpful getting both the theoretical/conceptual info as well as the workflow approach on how to use MoI on these kinds of objects. Actually, just knowing that there are relatively straightforward solutions for shapes like the spout is encouraging, and the final result is much cleaner than I could get out of modo, so I'll keep playing around with the demo. Seems like there is definitely a spot in the toolbox for MoI.

So what Steve was pointing out was using the network tool, has no mechanism for maintaining the tangency to surrounding surfaces...

So here if I broke this edge here to enable a blend at a much higher value in this upper area:



To look like this... I might try to fill in this last area with a network:



So I could select these curves and run network on them:



And I would get a nice surface patch in there:



But at the moment, MoI doesnt have a means for the network patch command to "Know about the surfaces next to it"... So you can get a lack of tangency from the surface previously made. You can see the hard edge here now..



So, building by "Patchwork" would be fairly hard or advanced as michael mentioned....

I think Michael said he was working on some surface continuity options.

I'm not working on them right this moment, but I have some good ideas on how to pursue some continuity functions for v3 though.

- Michael

That would be awsome Michael.

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