Paul,

It's not really a question of whether or not it can be done. Building

solids

in Rhino from surfaces is the way you used to have to do it in UG. So I

have

plenty of experience doing it that way. In UG most of this effort is
automated. For instance to make the shell I would model a solid then

hollow

it out. If I want ribs I extrude and add them. Then put a blend around

the

rib. If I move the construction curve in UG the whole thing updates,

with

the rib in the new location. Or I can replace the construction curve and

the

rib takes the new shape automatically, blends and all.  That same task

in

Rhino would see me deleting the rib and blend surfs. Then untriming the
shell surf. Then creating that geometry all over again. Then re-joining

all

the surfs to make a solid.

 What if I want to make the part .08 in thick instead of .1. I would

have to

rebuild everything. In UG I just change the thickness parameter,

everything

updates. Rhino is a great package, but parametric solid modelers are a
requirement for what I do. It is a time issue. I agree Rhino has

improved

the blending ability in recent upgrades which I have. But in UG I have

many

options: regular spherical blends (as in rhino) except with parametric
variable radius capability, variable conics, soft blend (follow a

specified

tangency curve) face blends, cliff edge blends(blends where one edge is

not

tangent). All of these have the capability of just changing the

parametric

radius and they update. Or have different radiuses at different points.

Or

change the degree of the conic along the blend using a specified

function.

Believe me if Rhino were capable of these things I would use it.

Yes true my fix is a kludge. It would be nice if it had a shell
command
and could do all those other things.

Paul Lamar

Paul,

I wouldn't call it a kludge. That is just what is required to make it work
for the CAD package you are using. I had a handle for a project that had the
dreaded all surfaces converging on a point problem (darn stylists). No
software I have ever used has been capable of doing this including UG. When
you ask it to hollow the shell you get self intersecting geometry. So I had
to build the whole thing using surfaces that were sewn together. I prefer
the term...work around. ;)

Monty

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