Nerdy Derby Wheels Keep Rolling!


We’ve been printing wheels… lots of wheel! We tested some at Madison Mini Maker Faire’s Nerdy Derby event last weekend, and we’ve been using Son of Megamax to crank out little plastic wheels.


Yes, we are printing 37 wheels at a time! And we’re using ABS filament from CoEx in Appleton, Wisconsin. They were kind enough to supply us with some spools of filament to keep SoM busying printing pretty much day and night!


I know you’re wondering how we keep an eye on all those wheels being printed. Well, when we’re not at the space we just check out the Milwaukee Makerspace Webcam. (As long as it’s pointed in the right direction.)


Coex 3D Printing Filament
(Thanks again to Coex for the filament donation!)

More Banned Nerdy Derby Cars!

I made the car “Sling Shot” to enter in the recent 2012 Milwaukee “Nerdy Derby.”  During a few initial test runs, my car proved to be more than 10 times faster than the super-clever winning car made by HaveBlue.  Unfortunately, my  car was banned from competition because it was considered a threat to the spectators’ safety!  The consensus was that it had “too much momentum, or energy,” and would hurt someone if it went off the track and hit them.  What does too much energy mean, you ask?  Well, kinetic energy is ½ X Mass X Velocity^2.  Really then, the car was banned because the velocity is too high: It is just too fast!  I’ve already minimized the mass by making the car out of pine, although I could have made it from Balsa Wood, or even entertaining alternate materials such as these.

Anyway, its no fun to think of how to slow Sling Shot down so that its slow enough to safely race, but still fast enough to win.  Instead, I made some new car prototypes that amp up the speed and danger.  If I’m going to be banned in the future, I may as well get banned with style!

Below is a photo of Sling Shot, which traveled the 40′ track length is 0.1 or 0.2 seconds, for an approximate average speed of 300 feet per second, or 200 mph!  Note that the block is anchored to the finish line, thereby stretching the surgical tubing which acts as a spring to propel the car.

I realized that the dominant energy loss mechanism is air resistance – largely because Sling Shot’s wheels don’t even touch the track.  You see, the car doesn’t follow the contour of the track, it just heads directly to the finish line, through mid-air.  I spent some time engineering a more aerodynamic shape to further boost Sling Shot’s speed, searching for a shape that would really slice through the air.  I even consulted a team of highly trained German aeronautical engineer friends, who all approved of my slingshot propelled Henckel Car.  With the improved aerodynamic design, it should easily be faster than the 200mph Sling Shot car shown above.

The other car I built this weekend is also based on Sling Shot, but incorporates some classy chandelier bulbs.  The numerous ‘safety’ lights alert the time keeper of the imminent arrival of the derby car – for safety.

Nerdy Derby ReCap

Derby Car

It’s been a few weeks, but honestly, it took that long to recover! Yes, we all survived Milwaukee’s First Nerdy Derby race (well, a few cars may have been damaged) so here’s a look at some of the coverage.

Ed put together this great video of the race…

Kevin put together a car that was deemed too dangerous (or was it ‘too awesome’?) but you can read about that here.

Sling Shot

Collin’s car won the “Longest time” category, and here’s a video of Rolling Thunder in action…

Have Blue put together a super-detailed blog post about his car, which definitely won the speed competition, and also won the “Run backwards up the slope and launch” category.

There’s more car photos on Flickr. I’ve been told a few people want to have another race, and this time we may even need “motorized” and “non-motorized” categories as multiple cars sported propellers, motors, ducted fans, etc.

I’m not sure if anyone bothered to keep track of all the winners in all the categories (we created about 8 categories you could win) but the main thing most people will remember is the fun we had. Kids and adults were cheering and laughing during the race, and also had a fun time just building cars out of all the scrap we supplied. It was probably the most awesome thing that happened at BarCampMilwaukee this year.

I’d also like to give a big thanks to Buggs, Vishal, and Brant for providing the track and running the race. A little organization goes a long way!

Nerdy Derby Car From The Future

I made the car “Sling Shot” to enter in the 2012 Milwaukee “Nerdy Derby” at Barcamp7 this weekend.  A lot of people were talking about adding motors and fancy electronics, but my car is powered by a spring – a 10 foot length of surgical tubing that is stretched to another block of wood that must be clamped down.  I added wheels, but they aren’t necessary – they don’t actually even touch the track.

Check out what may end up being the only two runs the car has.  Fortunately, JRock captured some video of them.  I’d estimate that the car took 0.1 or 0.2 seconds to travel the 40 foot length of the race track, giving an average speed of 300 feet per second (200 mph!).  The great part about this “sling shot” design is that the car is accelerated by the surgical tubing spring throughout the first 30 feet of the track – until the surgical tubing is completely unstretched.  “Beautiful!”


Who wants a Junk Car?

Junk Car

Don’t feel bad for Junk Car… Junk Car does the best it can with the parts it’s been dealt. As we prepare for our Nerdy Derby, we’ve been working on our own cars, but we also want people to bring the cars they’ve made, and we know that some people will show up, and say “Damn! I wish I had a car!” so for those people we’re assembling a box o’ parts. We’ve got some bodies and wheels, and I’m sure the folks at Bucketworks can dig up some crafty materials for decorating the crap out of your crap car. (Remember, there are awards for style as well as speed!)

Spare Parts

And hey, don’t feel bad for Junk Car, it’s just a name. In the hobby robotics world people often use the term “Junk Bot” to describe any robot cobbled together out of spare parts they had lying around, so this is pretty much the same thing.

(And yes, those are laser-cut wheels, and 3D printed wheels you see in the photo.)