Tag: nerdyderby

Categories
Uncategorized

Printing 4-Up

Wheel 1-Up

We’re planning a Nerdy Derby event at Maker Faire Milwaukee, and like last year, I wanted to 3D print a bunch of wheels, and yes, it is fun designing strange wheels. Most of my designs this year are refinements from last year, and I wish 3D printing were as simple as hitting “print” and walking away, but that’s not always the case.

Wheels 4-Up

I found that if I printed one object, it worked fine. If I tried multiple objects, things were failing, either with one or more objects, or everything. I’d try to print two wheels at once, and one would work, the other would fail. Slic3r allows you to generate the G-Code needed to print files, and has an option to print multiple objects, either by printing them all at once, or one at a time. Both of those options just weren’t working for me, for whatever reason. (My 3D printer is a RepRap I built myself, and yes, it has issues now and then.)

But you know the old saying… if you can’t fix it in hardware, fix it in software! So I did… You’ll notice that the image above shows four wheels with a small square connecting them. I ended up pulling an STL file into OpenSCAD (my favorite 3D modeling application) and then duplicating it four times and adding a small 1mm tall square between them to connect it all into what the printer would see as one single object.

Wheels Printed 4-Up

It worked! I’m now seeing much more success with printing, and getting sets of 4 wheels connected with a thin piece of plastic that’s easy to remove. Oh, I should also mention that our friends at Inventables were kind enough to donate some filament to this cause, so if you have fun building a car with 3D printed wheels at Maker Faire, be sure to stop by the Inventables booth and thank them for making it happen.

(BTW, MegaMag is printing way more wheels than I am, and going 40-Up!)

Categories
Uncategorized

A Nerdy Derby Thanks

The Track

Well, we somehow survived another Nerdy Derby event, and while it was a little chaotic, those involved definitely had a good time. None of this would have been possible without the help of Frankie and the DCRL at UWM. Be sure to check out Frankie’s most recent post about building the track.

Track Plans

Everyone at Milwaukee Makerspace was surprised at the size of the track. We’ve had the CAD files for more than a year now, and talked about building an “official” track, but we owe Frankie (and his students!) a big THANKS for making it happen. They put a lot of work into it, and we definitely appreciate it.

Last year we just used a plain old Pinewood Derby track, and I must say, this year was way more interesting! We had a lot of kids building cars, and besides the cars looking hilarious and awesome, we learned that cars fell off the track… a lot! (This turned out to be a good thing.)

Derby Car

Kids are pretty darn creative, and they came up with some crazy cars, and many of the cars fell off the track and hit the floor below, and parts flew off. I was joking that this taught them a valuable lesson every member of Milwaukee Makerspace already knows: When something breaks, we fix it. I don’t remember seeing any kid get upset about their car breaking into 10 pieces. They just picked up as many pieces as they could find and headed back to the build table to try again.

So here’s the deal… We’re going to have another race, maybe before the end of 2013, maybe early in 2014, but this time we’re gonna let Frankie choose the date so he will not miss it!

(If you’re interested in sponsoring the Nerdy Derby, get in touch with me. It really is a fun and educational hands-on event for kids… of all ages!)

Categories
Uncategorized

Derby Wheels

If you remember Milwaukee’s last Nerdy Derby, we tried to supply lots of pieces for people to build cars with. I ended up laser cutting a bunch of wheels, as well as 3D printing some wheels… take a look at the junk car post from last year.

Well this year I started printing wheels, and then decided that plain old boring wheels just wouldn’t do, so here I present a progression of wheels I’ve designed so far. I’ve only printed about 1/4 of them, but I’ll probably give them all a try before the big Nerdy Derby event at Milwaukee MakerFest on October 19th, 2013.

wheel001
The plain old boring wheel from last year.

wheel002
Speed holes… should use less material, but may not actually print any faster.

wheel003
Indent, for no particular reason.

wheek004
More speed holes, this time done using a proper for loop.

wheel005
Reverse spokes?

wheel006
Howdy partners! It’s a wagon wheel!

wheel007
And a steering wheel!

wheel008
And an Aperture wheel?

wheel009
Wheel wheel wheel wheel wheel…

wheel010
Tri-force wheel?

wheel011
Weird wheel?

wheel012
Starting to do some hull action for more 3D-ish wheels.

I will say this, I am no expert at designing wheels, but it’s been a lot of fun and a great design challenge, and I really do enjoy tinkering with OpenSCAD to create things.

Oh, and then I wanted to do a spiral wheel, and did some searching, and found this great wheel library, so use that if you really just want awesome wheels and don’t care as much about screwing around with code to learn things on your own. (Or, us the Highly-Configurable-Wheel library and learn from it!)

Categories
Uncategorized

(Additional) Nerdy Derby Cars

Great White

There’s a great post over on the Milwaukee Makerspace site about Milwaukee’s First Nerdy Derby, including some sweet video, but I’m mainly going to talk about my own cars here. :)

I spent a lot of time before BarCampMilwaukee7 getting ready for the event, but I also found a bit of time to fabricate a bunch of parts for people to build cars with, so I was down to the wire when it was time for me to make more cars. I already had Poundin’ Sand, my fully laser-cut car, but I wasn’t content to just have one car. (I had heard Jim R. from the Makerspace had five cars. He didn’t race that many, as I think one or two of them exploded during testing.)

My second car was titled “Great White” and was a 3D print of Mr. Jaws. I ended up kicking out some quick axle mounts in OpenSCAD and just hot gluing them to the bottom of Mr. Jaws. They probably weren’t on straight, but I didn’t take the time to care. In the category of 3D printed cars… I still came in second! Ed managed to build an amazing 3D printed car, and the worst (best?) part is, he pretty much had the same idea as I did, but he managed to succeed. (Print time and print failure were the two biggest concerns for both of us.) I ended up using stock wheels instead of the 3D printed wheels I made a few weeks earlier, which seems silly as I could have gone for a full-on 3D printed car… oh well.

RasterMobile!

My third car was the RasterMobile! which actually consisted of a block of wood from a real Pinewood Derby kit, turned sideways, with two holes drilled all the way through, and 5/16″ threaded rod with inline skate wheels attached. I had skate bearings that seemed to turn well, I had some weight and mass, and it was painted black with RasterWeb! stickers on it. What could go wrong!?

So how did my cars do? I didn’t expect much out of Great White, as it was really light, and the wheels were probably not completely straight. It rolled down the track, so that’s all I can report on that one. I still think it looked cool and was a neat idea. The RasterMobile! didn’t do as well as I expected. I thought it would fly down the track, and I suppose it did, but the mass of it probably slowed things down too much at the bottom. I did get a some satisfaction that Gary saw the skate wheels, ran to his car and ripped apart his inline skates just to try to beat me with my own idea. :) Oh, the RasterMobile! also had an accident where it jumped out of its lane, so that certainly didn’t help things.

So which car did the best? Surprisingly it was Poundin’ Sand that performed the best out of my three cars. I wasn’t sure the laser-cut wheels would be up to the task, and I questioned whether not gluing the 3 layers that comprised each wheel together was a good idea or not, but it did alright!

Poundin' Sand

There’s been talk of doing another race in the future, so I may not be done building tiny cars…

Categories
Uncategorized

Poundin’ Sand – Complete!

Poundin' Sand

In my last post about my Nerdy Derby car, all you saw was a bunch of laser cut wood pieces… well, here’s the final car.

Poundin' Sand

It’s almost dimensionally the same as a standard Pinewood Derby car. The body is constructed out of panels that were laser cut rather than a block of wood. Because it’s hollow inside, I filled it with sand. Why not lead? Well, someone else is already doing a car out of lead. I also though about marbles or something else that would roll around inside. I also thought about making one with acrylic and filling it with water.

Poundin' Sand - Wheel

The bottom has two pieces of wood attached so I’d have something to pound the nail into to attach the wheels. I glued the two piece together and then drilled a hole between them. (The wood is just 3mm thick, so layering made sense.)

Poundin' Sand

I spaced the wheels the same for the front and back, so there really is no front or back… it’s the same either way. You’ll also notice I did a terrible job of placing the lettering. I just added it to the side panels without thinking about how the wheels would get in the way.

Poundin' Sand - Wheel

The wheels are also 3mm wood, and I’ve sandwiched three of them together to make each wheel 9mm wide. I was going to glue the layers together but I figured I’d just put them on and allow them to spin independently (if possible.)

If this car wins nothing besides the “laser cut wood filled with sand” category, I’m fine with that. I learned quite a bit in the process of building this, and if I build another car, I have some experience to build on. (I also managed to cut a big pile of wheels and have nails to fit them, so we can have supplies for people to make cars on the spot.)

Update: Files are now on Thingiverse.