Several helpful responses assume you want to design hull shapes, but you
didn't mention your particular interest or skill/experience level. I'll
pass on my own experience coming from a different angle in case it's
relavent.

Many times you want to simply lay out furniture, hatch details,
plumbing, technical drawings of things such as layups, deck fitting
placement, etc. For this a "traditional" CAD programs, 3D or even 2D, is
the tool of choice. In many ways, the more powerful the tool, the harder
it is to control and get results. (Cast your mind back to when you tried
to use Styles in Microsoft Word...)

I have used an old version of a 2D CAD program from Intergraph called
Smartsketch for documenting many contruction tasks, and it continues to
be most adequet. It's good points at the time I got it (4 or 5 years
ago) included powerful user interface features such as moveable origin,
automatic double lines, automatic connecting lines, automatic
dimensioning, and quite powerful parametric symbols. I extremely happy
(after several months looking) to find a user interface that was
understandable, accessible, and addressed immediate needs. It still took
me more than 40 hours work with the program before I got to the point of
"just doing" a drawing (I was, and am, not a draftsman).

For recording specific details and printing them for use in working with
others, less is more. Smartsketch is now in version 5 (I have v3). The
others that looked very good and were within reach for a "shade tree"
drafter included Vectorworks (Mac and PC), Vellum (with 3D as well, but
much more expensive). I have heard that AutoCad finally got it close to
right with their basic user interface, so their low-end "home" version
might also be a good tool; at the time I was looking they had an
impossibly dense interface.

CAD provides an extremely complex set of tools, and most people will
probably not be able to use anything except the most basic software, and
then only if it has a clean and accessible user interface and top notch
tutorials and support. If you haven't used CAD before and want it for
technical drawing like I did, check out one (or more) of the programs I
mentioned above and don't crash and burn trying to decipher a "free"
offering, or drown in the maze of one of the super programs. I think the
other poster's link to the Nurbs article makes some similar points
regarding the hull design programs - there's a huge amount to learn and
it takes real work to get decent results.

Rufus


Freddie Richard wrote:

What would be a good computer drafting program for ship design etc?

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Thank You,
Freddie L. Richard