Little advice on rhino

[vinceUK]

Hy, everybody, I'm a french student (in UK Southampton) in boat design. I would just need a little tip on rhino. I have imported a hull made on maxsurf (format IGES), everything is ok. Then, by using Surface/ Edge curves I make a transom and a deck. Everything is still ok. But I do not know how to make a cockpit. For instance, the trim and boolean difference functions do not seem to work when just putting a box through the deck and trying to make it become the cockpit. I hope I have been clear enough. Thanks a lot if you can help me

[Andrew Mason]

Maybe do it in Maxsurf and import it into Rhino??

[vinceUK]

Maybe I do not know but the trimming function in maxsurf that is used to make a cokpit is not recognized in rhino. I mean that the dack is flat when imported in rhino however it was with a trimmed cockpit originally

[Tim B]

This is not a job I'd do in Maxsurf (Sorry, Andrew).

So, in Rhino....
The normal process is to draw (in 2D plan view) where you want the cockpit, then extrude the curves to intersect the deck. Use the "split" command between the deck surface and the cockpit "walls", then delete the bit in the middle of the cock-pit and carry on from there.

I think you probably need to practice using Rhino a lot.

If you're having trouble, give me a shout Tim@MarineDesign.tk and I'll see if I have some free time to help you out.

Tim B.

[vinceUK]

I will not permit myself to disturb you. I try and i'll tell you. Thanks to support beginners. (excuse my english..)

[vinceUK]

Maybe I'm trying too hard.. I do not reach but I do not understand why. A boolean difference should make "a hole "in the cockpit in the cockpit, shouldn't it? Let's work on the keel, I will try again later

[Tim B]

you can think of boolean operations for solids, use split for surfaces

Tim B.

[Tim B]

you can think of boolean operations for solids, use split for surfaces

Tim B.

[fencer]

There are times and situations when boolean difference does not work. Look in the help file for *when boolean does not work*. see if ur case is one of those. The help file suggests alternatives also.

/G

[MikeJohns]

Tim B

One big problem with the Rhino-Maxsurf approach is that Maxsurf does not import trimmed surfaces. So be carefull if you intend to take your model back to Maxsurf for rollover curves etc.

[Andrew Mason]

Mike

Maxsurf V12, which is in beta test at the moment, does import trimmed surfaces from Rhino. It should be shipped to users in the next few weeks. Note that the import is using native Rhino 3dm files.

From the Maxsurf V12 user manual -

Maxsurf - Rhinoceros bi-directional data exchange
Rhino .3dm files may now be imported and exported directly to/from Maxsurf.
Full NURBS surface geometry exchange is supported as well as information such as surface colours, names and trimming.

Trimming Information
Due to the inherently different trimming models used by Rhino and Maxsurf, importing trimmed models may take some time. When importing a trimmed surface from Rhino a dialog box will appear asking whether Maxsurf should try and replicate the trimming regions. All trimming within Maxsurf is dynamic and based on surface/surface intersections to define the regions within the surface. Rhino uses a static trimming model which allows trimming of surfaces using arbitrary curves. When one of these surfaces is imported into Maxsurf these arbitrary curves are converted to a curve in the surface. The curves are attached to specific parametric positions on the surface so that the dynamic nature of the trimming is maintained; i.e. when the surface changes, the trimming is not lost. Note however that the shape of the trimming curve will change as the surface is modified. These curves may be displayed using the Display | Contours dialog.


Andrew

[Windvang]

Try rebuilding the deck surface and make sure the box is closed and intersecting the deck everywhere.

[vinceUK]

The surface/edge curves function is the most adapted to make the transom and the deck, isn't it? And thanks to everyone for your help

[vinceUK]

I have tried with a new hull, built a deck and a transom and them made a boolean difference between a box and the deck and it works perfectly. It makes a wonderful box-shaped cockpit. I do not understand why I hasn't worked on my first hull. Thanks

[Tim B]

I assume that you joined all the surfaces in your new hull. If so, Rhino thinks of it as a solid, hence boolean operations are possible. See my previous post.

Andrew, It's good to hear that Maxsurf will do trimmed surfaces in the next release. Any plans on porting it to Linux?

Tim B.