Hi Roger, are these part of some larger structure?

Usually for something similar to this you will be better off building a larger surface with a simple 4-sided outline similar to this:



And then trim that regular surface to produce the irregular edges:




That's instead of trying to build a surface through the irregular curve layout directly like you are trying to do.


If you can't build a larger initial surface and trim it, then you would probably need what is called an "N-sided patch" tool which tries to fit a surface through a set of curves. MoI does not have a tool for that currently, you would need to use Rhino for that particular one, but also it can be a bit hit or miss anyway. If it is possible to build a simple surface and then trim it that is usually better.

- Michael

And usually you would have the cutting curves be planar 2D profile curves.

- Michael

Hi Roger...

How about use Sweep ?
Is that close your requirement ?

Hi Anis,

Yes sweep works exactly as you have described - but it is not what I am looking for.

Thanks Michael - that is what I was looking for. I thought that I might have been doing something wrong - but it is simple when explained. Thanks.

R

Actually it is the transom or more correctly half transom for one of my boat designs. Have managed to get all the other components modelled but this one had me stumped. Thanks again.

R

Hi Roger, you're welcome, I'm glad that technique worked for you!

That kind of strategy of "build it larger then cut pieces off" can be a helpful strategy in many circumstances with NURBS modeling.

It can take a while to get used to that method though if you are coming from a poly modeling background, since it is a much different approach from what you do in a poly modeler.

One thing that can help is if you kind of imagine how the thing would be manufactured - starting with some kind of simple piece of stock that then have parts cut off or holes drilled in it, etc... - some NURBS modeling strategies can often times tend to resemble that.


- Michael

"build it larger then cut pieces off"

Yep - kinda like making a manifold on a milling machine. Clamp down a block of metal. Cut away everything that doesn't look like a manifold :)