Mad for 3D CAD
BY SAUL GRIFFITH
Ilove the third dimension. I’m glad I’m not flat. I love figuring out how to pack the most luggage into the smallest trunk, and I love optimizing the
stacking of the dishwasher to fit the most plates and
glasses. It should come as no surprise to you that
I love — nay, I’m addicted to — 3D CAD programs.
My current large-scale project is to design and
build the things I need to make my lifestyle as low in
energy use as possible, while improving or retaining
my quality of life.
Yes, I’m doing it for environmental reasons: we are
heading toward disastrous climate change, and we
need to make huge changes to the way we live. More
than half the problem is figuring out how to live well
with less energy. There are innumerable things to
do in this domain — efficient devices and retrofits to
invent — and if all makers out there take up a similar
call, the world has a shot at survival.
How does this relate to my love of CAD? Well, right
now I’m building a hybrid human-electric, tilt-steer-ing, front-loading tricycle, code-named Flying Nun.
Design projects of this kind hugely benefit from
3D CAD programs: doing a lot of the prototyping
work in virtual space prevents wasting material
resources and energy in the development stage.
I love the parametric design engines that let me
push the assemblies of components around to
make sure the dynamics of the bike and the quality
of the ride are solved for, before I ever cut metal.
I also find 3D CAD to be the ultimate video game.
For me, it’s like the best possible combination of
Tetris, jigsaw puzzles, sudoku, and Grand Theft
Auto. The meditation of spinning the objects in 3D
until you have the pieces just right is one of the
most pleasurable activities I can think of. It takes
me straight to that place of “flow” that Mihaly
Csikszentmihalyi talks about.
I’ve used pretty much every CAD package, from
Solid Works, to Autodesk, to Pro/E, to Rhino, to
SketchUp, to Alibre. They’re all powerful and useful
for different purposes. Occasionally I’ve resorted to
writing my own CAD programs when the existing set
couldn’t do the job.
One great thing about 3D CAD today is that there
are more and more CAD models in online libraries,
so you can get many of the pieces you need without
having to draw them yourself. All of the nuts and bolts
in my trike came straight from McMaster Carr’s 3D
model drawings at mcmaster.com. I was also able
to build upon other peoples’ models of various bike
components that they had posted online.
Another great thing is how well 3D CAD plays with
the CAM (computer-aided machining) technologies
that have grown up and evolved with CAD. Now
that I’ve finished the design of my trike, it’s only a
matter of days to have all the components made and
ready for assembly into the final product. After I farm
out the CAM to various skilled fabricators, every
gleaming piece of machined aluminum and welded
steel that returns is a thrill.
It takes a village to build a prototype. I could do it all
myself, but I’ve learned that for every fabrication process out there, there’s someone who does it far better
than I do. I may know how to make a strong weld, but
I venerate those people who can make a perfect bead
every time. I know how to use a Bridgeport mill, but
love working with people who mesh years of hands-on
machining experience with the new digital, hands-off
CNC. There’s still art there; it’s just different now.
Throughout this project, though, I’ve been lamenting one thing. I’ve become lazy with these amazing
new 3D design tools. I can’t even remember what a
title block or correctly dimensioned drawing looks like.
My high school taught a lot of engineering trade skills,
and as a 16-year-old I could do fully specified technical
drawings by hand, appropriate for any machinist to
build. We laboriously drew sheet metal patterns from
first principles. Everything was done in 2D. Now I just
make ten drawings with lots of redundancy instead,
and liberally use the “auto-dimension” function.
I remember the smudged pencil erasings, the T
squares and isometric circle templates. I don’t miss
them, but I lament the passing of their arcane beauty.
I’m constantly reminded that having constraints is
good for design, so I wonder whether I don’t have
enough constraints with 3D design tools. Not that it
stops me from yearning for every new release of the
latest video game. Ahem, CAD program.
Saul Griffith is a new father and entrepreneur. otherlab.com
12 Make: Volume 21