LEGO Gear Ratios

Gears and Drivetrains in LEGO MindstormsAnother useful tool for getting all creative with your LEGOS. A handy tutorial showing you common ratios for the gears that are common to the LEGO Mindstorm kit. You can also find these gears in a variety of other LEGO sets. And if your totally flummoxed about what gears are just having a look around should answer some of your questions.

Gears and Drivetrains in LEGO Mindstorms

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LEGO Technic Motor Box
8735 Technic motor from
Revised LEGO Mindstorms NXT from

Amazing LEGO Motor FAQ

LEGO motor FAQIf your LEGO construction skills have progressed past the point of building stuff out of the instruction booklets then you have undoubtedly had the desire to play with the versatile LEGO motors. The LEGO motors are amazingly handy, I can’t say enough good things about that really. The biggest question is what one to use? As they are a bit pricey (hey, these are LEGOs after all) picking and choosing the style might save you some valuable cash. I personally like the 8735 motors myself, but that’s because I have a few from my old Mindstorm kit.
The list give you important info like motor RPM, stall current, torque, and even efficiency. Just the stuff you need to maximize your project. I guess it goes without saying that you can use these motors for non-LEGO applications as well. Just let your creative mind go wild.

Lego 9V Technic Motors compared characteristics

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8735 Technic motor from
Revised LEGO Mindstorms NXT from

The Bamboo and Carbon Fiber Bike Frame

Bamboo bike frame
I got a comment on my post about bike frames made of bamboo today and figured it was worth of a new post

The bike is made from Bamboo that has been smoked and heat treated to prevent splitting. Lugs are available in carbon fiber or hemp fiber, for the all-natural look. The chainstays are available in carbon fiber for extra stiffness in the drivetrain.

As Sean says they are working on the paper and epoxy versions. I’m sure he is joking but hey, he knows his Gibson! If I were in the market for a bike and I wanted something that was light weight and strong but I didn’t want full carbon fiber I’d choose bamboo hands down. The stuff is strong as hell and looks great.


R/C Helecopter With Rockets!

ROV with teethOne of the captions on the page says it all:

Unmanned Attack Helicopter, Ver. 2, 2004
Gas Powered Radio Control Helicopter modified to carry and remotely fire model rockets

Oh yeah… This would liven up the company picnic don’t you think? I wonder how he managed to ignite the rocket without throwing the chopper into a nasty spin? Any one else have something like this? BB gun mounted on a glider maybe?

The artist also has some very impressive sculptures listed in his online portfolio. I like the ‘Bronze Skull’ ones myself.

[via jaf project]
The Sculpture of Christopher Conte
Bronze Skull prototype

An AVR-based Analog Plotbot with an E-Paper Display

This is just perfect! Using a Magna Doodle as an output device for a computer is just brilliant.

What do you get when you mix a 1970’s style analog chart recorder, an 8-bit microcontroller, and a Fisher-Price Doodle Pro? A truly 21st century toy: An analog PlotBot with e-paper display technology!
Our machine is based around a vintage analog X-Y data recorder. Its original purpose in life was to perform basic laboratory data collection, plotting two voltages against each other, and was one of the primary tools for that purpose right up until computers took over that job in the 1980’s. Because they were once so common and are now generally obsolete, it’s quite easy to get one of your own. There are usually several under $50 on eBay at any given time, and that’s where we got ours. …
The other major modification that we’ve made is that we’ve replaced the pen and paper with what seems like out of reach technology: an inexpensive and readily available e-paper display: the panel from a Doodle Pro. …
The Doodle Pro is a descendent of the Magna Doodle, a classic children’s toy dating to 1974. (I’m not sure what makes this a “Pro” anything, however.) It uses a simple magnetophoretic display, where ferromagnetic particles are suspended with near-neutral buoyancy in an opaque, viscous white liquid. Using a magnetic stylus, you can attract the black particles to the top surface, or with a magnetic “eraser” on the bottom side, pull the particles away, leaving only the white liquid visible.

Evil Mad Scientist Laboratories – An AVR-based Analog Plotbot with an E-Paper Display