Lego: The ultimate prototyping material. Seriously. By Bob Parks
Adrian Marshall decided that he’d need a very Sooner or later, however, Legos run out. Factory
convincing scale model to sell his latest idea. The roboticist Marshall says he often finds himself in a
British designer of factory robots was to meet crunch for specific pieces, so he orders large batches
the board of directors of a large food company, from educational distributors online. Seekers of rare
who wanted an industrial robot that could move parts must look to eBay, trade among Lego enthusi-ten arms independently and burn a picture of the asts online, or participate in closed auctions listed in
Rugrats cartoon characters on pancakes randomly newsgroups and Lego builder’s sites like lugnet.com.
placed around a moving skillet. It had to be done Lego has some inherent limitations as well. While
in under 0.8 seconds in a hot industrial kitchen. Of some builders pride themselves on using only
course, he used the only prototyping material suit- what’s in the catalog — Chicago’s Jonathan Brown
able for such a tough job: Lego. created a Rubik’s Cube solver and Lego juggler using
“I always use Lego to present to customers,” says only virgin bricks — even Brown concedes: “[Legos
Marshall. “If it’s simple enough to be made from have] lousy strength-to-weight characteristics.
Lego, then the scaled-up version will be robust They’re great for small models, but not so good for
enough to survive in the field.” large models.”
It may be ironic that a toy may be the greatest In making factory prototypes, Marshall reinforces
prototyping medium ever invented, but since the his structures with side plates of medium-density
arrival of the primary-colored plastic blocks in 1949, fiberboard, aluminum, or steel. “Fine adjustments to
engineers have used them to envision new prod- geometry aren’t easy,” he notes.
ucts. And with the advance of Lego Technic in the To make Lego creations more rugged, MIT’s Raffle
late 1970s, inventors could spec out more compli- uses hot glue. Meanwhile, professional Lego sculp-cated machines with wheels, gears, and motors. tor Eric Harshbarger swears by Oatey All-Purpose
“Technic is coming from the engineer’s mind- Cement. (He once used seven pounds of the stuff to
set,” says Hayes Raffle, a researcher using Lego to build a full-size office desk as part of a commission.)
develop modular robot toys at MIT’s Media Lab. Adjustments to size work best using the carbide
“You can replicate the movement you find in motors cutting wheel on a Dremel; with flat plates, the ex-and other mechanical linkages quickly and cheaply.” perts suggest lightly scoring an X-Acto knife along a
Now, dozens of university programs across the steel ruler and then making deeper subsequent cuts.
country supply Lego Technic for students to design In the end, Marshall’s client was blown away
everything from unmanned military vehicles to by his pancake-stamping machine and ordered a
laser-surgery devices. full-sized version in stainless steel to the tune of
Part of the Lego prototype popularity may be that $200,000. He used a stereolithography machine
everyone seems to have a cache of blocks in a closet to make custom parts for a second prototype and
somewhere. That’s certainly the case with Tim recreated the design virtually in 3D Studio, a CAD
Abbot, an Indiana-based entrepreneur, who used software program. (Other Lego builders hone their
a Dremel tool to cut small holes in his son’s blocks creations using LDraw, a free CAD software made
and built an innovative backyard sprinkler system. especially for Lego parts.) The toy may not be the
Abbot’s Hydro-Edge will be sold nationally this sum- best option for going into production, but it’s great
mer. Or how about Kevin Mackie, from Scotland, who for delivering a proof of concept.
used Lego to build a prototype new drum pedal?
The design is now used by musicians including Iron Bob Parks ( firstname.lastname@example.org) lives in Vermont, where he
Maiden, Chick Corea, and James Brown. contributes to Wired, Business 2.0, and other magazines.
Legos from the private collections of Kindy Connally Stewart and Branden von Rohr