.FLYINGHEAD PRODUCT REVIEW
.TITLE More power to Forbidden LEGO
.AUTHOR David Gewirtz
.SUMMARY Nothing beats sifting through months of Congressional testimony to make the prospect of building a ping-pong shooting machine virtually irresistable. This was the opportunity facing me when the book Forbidden LEGO arrived at Computing Unplugged for review. What happens if you marry a power drill to a LEGO kit? This and other questions are answered in this wonderful article.
.OTHER
Nothing beats sifting through months of Congressional testimony to make the prospect of building a ping-pong shooting machine virtually irresistable. This was the opportunity facing me when the book Forbidden LEGO arrived at Computing Unplugged for review.
.H1 LEGO? You’ve got to be kidding.
Prior to this, I hadn’t paid any attention to LEGO toys since my childhood. For those keeping track, that was back in the Johnson Administration. So I had no idea how those little bricks could be even slightly forbidding.
Well, apparently, LEGO’s come a long way, baby!
Actually, it really has. As you can see in Figure A, LEGO parts are no longer just the little bricks we all remember. Among the seven thousand or so parts LEGO offers are beams, gears, sprockets, connectors, axles, and more.
.FIGPAIR A This is the set of parts I used in the ping-pong shooter. Way more than just bricks.
LEGO has also spawned a kit for building robotics that’s really quite darned impressive. In fact, LEGO’s been in the robot business for more than ten years and the Mindstorms NXT robot is a Bluetooth-equipped robotics system that’s the rival of any kit robot I’ve seen to date. We’ve got some books in on Mindstorms NXT as well as the robotics system itself, and we’ll be reviewing them all soon.
I didn’t pay much attention to LEGO until now because I always thought LEGOs are for little kids. I was wrong. There’s a huge interest in LEGO building among adults. By exploring Forbidden LEGO, I was about to find out the appeal of the modern LEGO system. As an engineer, what I found was almost irresistable.
.TEASER Tap here and enter a forbidden world. Forbidden LEGO.
.H1 Forbidden LEGO
The book Forbidden LEGO comes with five projects:
.BEGIN_LIST
.BULLET A paper plane launcher
.BULLET A candy-coated catapult
.BULLET A ping-ping cannon
.BULLET An all-terrain LEGO, and a
.BULLET A high-velocity automatic LEGO plate dispenser
.END_LIST
The book is called Forbidden LEGO because the LEGO design standards are such that the LEGO company is not real keen on their products launching objects and otherwise potentially causing harm. That, of course, was the real appeal to me.
.H1 Building a project
The ping-pong cannon caught my eye. I decided to build it.
This is where I ran into my first problem: parts. Fortunately eBay was there to help. Figuring that there couldn’t be too much variety in LEGO parts (I was to be proven quite wrong), I bought a 50-pound lot from eBay. Explaining to my wife why there was a 50-pound box of LEGO parts arriving at the house made for an interesting conversation. Fortunately, Denise is very tolerant.
Even after spending a few evenings in front of the TV sifting through LEGO parts (there’s an image that says "mature"), I realized I wasn’t able to assemble all the elements needed. After contacting the publisher, who put me in touch with the authors, I found out that the five projects in Forbidden LEGO were made up of parts from a wide variety of LEGO kits, including some that have been off the market since 2001.
That’s the first strike against the book. If you want to build the projects, you’re going to have to forage, have a large collection of LEGO parts already, or spend a surprisingly large amount of money on eBay. There is a thriving LEGO aftermarket on eBay and you’d be shocked at the prices and variety.
I placed another order on eBay for another lot of gears and cogs and such, and although I didn’t get all the parts I needed, I did find enough to let me substitute some parts for other parts.
You readers out there who are engineers are welcome to cringe right now. Yep, substituting parts in an engineering design is about as reliable as substituting barbeque sauce for just about any other sauce in cooking. You’ll get food, but not necessary food anyone will enjoy.
Anyway, I substituted a motor that came in one of the eBay lots for the one specified by the authors. Buying the specified motor online would have cost fifty bucks or so, and this project had already way exceeding both its time and dollar budget.
And yet, I wanted to build a ping-pong cannon and I could not resist the lure of shooting projectiles. After a few nights of very embarrassed futzing, I built the device, as you can see in Figure B.
.FIGPAIR B This is the ping-pong cannon, modified to use available parts.
OK, time for the first confession. This thing was amazingly fun to build. With the combination of parts, including things like gear reductions, the LEGO system has actually become an engineering prototyping system of rather astounding proportions.
.H1 The frustration
It was also a bit frustrating. The parts problem haunted the project throughout. In addition to having no indication within the book of either part numbers or where to find the parts, the bill-of-materials for the ping-pong cannon was missing mention of some parts: the long tubes needed to support the projectile balls.
And, sadly, the device didn’t work well when finished. I had to tweak it a lot to get it to thwack the ball at all, and when it did, the ball just fell out of the launcher. There was no satisfying fling across the room, as I had hoped.
It could be that had I used all the original parts, the thwacker would have thwacked better. I could be that had I used ping-pong balls instead of the slightly heavier golf whiffle balls, the thwacker would have thwacked better. It could be I missed something in construction. Anything’s possible.
I can’t completely blame the authors for a failed design. Especially after I had so much fun tinkering with it.
But I couldn’t leave it there.
.H1 More power
To the continued terror of my wife, I’m a student of both Tim Allen’s "more power" mantra and the Mythbusters "well what would it take?" approach to project design.
What would it take to thwack a wiffle golf ball across the room? Well, of course the simple answer is "more power".
I decided the project needed a new motor. So I replaced the little LEGO box motor with an 18V hammer drill. I turned off the hammer function, but since this drill can force a screw through two 2×8 planks in about five seconds, I figured it’d be able to thwack a wiffle golf ball. Which brings us to Figure C.
.FIGPAIR C Let’s add a power drill!
As you can see in the figure, I connected the motor shaft straight into the drill. I also flipped the wheels upside down and used blue tape to provide a structural integrity system. Figure D gets you in closer, so you can see the wonder of my redesign.
.FIGPAIR D Take a closer look at my masterpiece.
So, here’s the thing. The main shaft is geared to a secondary shaft. That goes through a reduction assembly that translates rotating motion to angular motion. Unfortunately, the gearing assembly also reduces the speed of the system, so even though the drill was rotating very rapidly, the thwacker moved very slowly.
I didn’t have enough gears in enough variety to re-gear the mechanism, so rather than getting a very satisfying (and hopefully dangerous ball thwack), I got a sad little thump instead, as the balls just dropped off the launch pad.
There is no doubt that with what LEGO offers, I could have re-geared and made something far more effective. Unfortunately, with publishing deadlines looming, I had to end the project here.
.H1 Conclusion
I sometimes live a rather surreal life. Tomorrow, I’ll be on Boston drive-time radio, talking about risks to national security and promoting my book, [[http://www.emailsgone.com|Where Have All The Emails Gone?]]. I’ve got another two radio interviews on Homeland Security, the White House, and our nation’s technology policy scheduled for next week. And yet, right now, I’m writing about and playing with LEGO. I told you. Surreal.
Coming back to our original subject, which was really supposed to be a simple book review, I have two questions I need to answer. The first is whether you should buy the book and the second is our overall rating.
Forbidden LEGO is a flawed book. You can’t just take it home and use it. Unless you’re hooked into the LEGO community (who knew there was a LEGO community?), you’ll have no idea where to find parts or even what parts to look for. And if you set out to build a project, the bill-of-materials won’t be accurate to begin with.
If this were a physical product, ZATZ editorial policy would require me to say it didn’t work and award it two stars. But this is a book. What’s a book supposed to do? Sure, it’s supposed to help you build things. But aren’t books also supposed to inspire, to introduce you to new things and to new possibilities? Of course they are. More than anything else, books should help you dream, help you explore new worlds, and open your mind.
Forbidden LEGO does that. It showcases five mildly violent projects and dares you to build them. It dares you to take these silly little plastic toys and turn them into something new and unforseen.
For me, it opened up the door to a whole lot of fun. I always thought of LEGOs as a young child’s toy. Software developers use terms like toolkit, development environment, and rapid prototyping. The LEGO system is a toolkit, a development environment, and a rapid prototyping tool, just for objects in the physical world.
Combining robotics with the flexibility and diversity of parts, you can make almost anything. I’ve seen LEGO-based soda machines and LEGO-based knitting machines. One project I want to build, now that I know this world is here, is a device to feed a stack of CDs (purchased, of course) into iTunes.
No, Forbidden LEGO didn’t talk about any of this. But it did show possibilities and variety and was most definitely inspiring. And for that, we have to give it a rating of four bricks out of five. Go ahead. Buy the book.
.RATING 4
.BEGIN_SIDEBAR
.H1 Product availability and resources
Read [[http://nostarch.com/flego.htm|Forbidden LEGO]].
Learn about [[http://www.lego.com|LEGO]].
Learn about [[http://mindstorms.lego.com|Mindstorms NXT]].
Read [[http://www.emailsgone.com|Where Have All The Emails Gone?]].
.END_SIDEBAR
.BIO
