RE: [PSUBS-MAILIST] Autocad advice?

[Alec Smyth <Asmyth@changepoint.com>]

I've been struggling with that one and have developed my own low-tech
approach, which doubtless a CAD expert would find simplistic... but it works
for me. Before this, I was really into using layers. 

I have a folder on my C drive called Bill of Materials. Within that, there
are sub-folders for the major components (hull, actuators, propulsion, etc.)
Within each of those, there are two folders; blueprints and photos.

Next, I created a part numbering system. The first two digits represent the
major component (the high level folders). I use sequential numbers for each
one of those series. And I reserve odd numbers for custom fabricated pieces,
even ones for off the shelf parts. Only the custom ones require diagrams,
but I photograph all of them. Plus there is a Word version of the BOM where
I keep track of the suppliers, type and cost of raw materials, etc....
anything I would need to know for estimating or purchasing. Each odd number
gets two files, a CAD file and a JPG, and I simply name them with the part
number itself, no description.

Each part then gets a digital shapshot, and if I made it, also a CAD file.
All the CAD files have a common template with boxes for the part number,
date, revision, change reasons, etc. I find the greatest value is in doing
these very detailed diagrams, as opposed to diagrams of sub-assemblies.
Although unfortunately sometimes I build the part first, then draw it later.

However, there is also a need for the big picture. For that I use two
diagrams of the entire sub. One is outlines, as it would appear to the naked
eye. The other is sections. I have not found a need to put hyperlinks
between these big picture views and the detailed part diagrams, although I
imagine it can be done. In fact, it would be a fun thing to do if you wanted
to put the whole thing on a web page so people could "take apart" the design
online. 

Until I started with the sub, my hobby was a 30 year old Jaguar E-type
(guess what is paying for the sub, hehe). A parts vendor had scanned all the
maintenance manual diagrams, which were of the "exploded view" type showing
multiple parts, into their web pages. So you would click on a major category
like "engine". On that picture, you could click on a carburettor and you
would get an exploded view of that. You would finally click on a little
washer in the carburettor, and the page would give you the part number,
price, etc. and even put it in your shopping basket. And all this built from
manuals that were 30 years old! It would be very nice to do that with a sub,
if nothing else for educational purposes.

Oh, also don't forget a folder named "obsolete ideas". That's where diagrams
go to die when I realize there is a better way to do something (there always
is). 

rgds,

- Alec

-----Original Message-----
From: John Farrington [mailto:jrf@prismnet.com]
Sent: Friday, January 25, 2002 3:37 PM
To: personal_submersibles@psubs.org
Subject: [PSUBS-MAILIST] Autocad advice?



I'm wanting to learn Autocad for my own use, and was looking
for some very general info on the proper techniques for designing
something with it.  Not the actual drawing of it, but how to use
layers and the organizition of drawings, and templates.

Maybe someone can answer some of these questions:

As an example, let's say that I was going to design my own
submarine, and do it in 3-D.

I want to be able to design the entire thing right down to the
o-rings, and all the way up to the overall shape of the sub.

My questions are with how I'd organize all of drawings.

I'd like to be able to pull up the overall drawing, which has
every single component of the sub, but would also like to
be able to look at, and work on, nothing but a single thru-hull,
or viewport.

ie.  Do I put a viewport frame in one drawing, the viewport acrylic in
     another, the rim in another, etc.?

     And then, somehow magically define the location of the viewport
     pieces and then be able to bring up an assembled drawing of the
viewport,
     and at a higher level, an assembled drawing of the entire sub.

I know that you can merge drawings, but I would prefer to not have to
do that to see a final drawing of the sub (this would require 8 identical
viewport drawings, etc)

ie. Is there a way to draw the hull section of the sub in one drawing,
and tell it 'at locations (x1,y1,z1) and (x2,y2,z2), there are things
called 'viewports', that are defined in another drawing, viewport.dwg.

So, if someone understands what I'm asking, and uses, or has used,
Autocad to a great extent, I'd be interested in hearing some of the
ways that designs like this are organized.


Thanks for any help.
-John