It was a fantastic, exciting, crazy day at Jeff and Abraham’s house. Lyle and I got up early, loaded the CrossBow Cart onto the back of the car, and drove over to Jeff’s house for one last test of the whole thing!
As you’ll see from the early part of the video, Our Best Backyard Roller Coaster Yet didn’t come off without a hitch or two. First of all, the track in turn one is a little too wide to accommodate the wheel assembly design on the CrossBow Cart. So, the wheels would pinch and slow the cart almost to a stop on entering the turn. Not the best result, especially in the first turn of the first test. I don’t mind saying, things got a little tense when we first saw that issue.
The rest of the ride was fantastic. Turns two and three are smooth, fast and strong. Jeff, Rob and the rest of the construction team did a great job.
At the end of the day, we decided to narrow the track by about half an inch in turn one. That way, the cart wont encounter too much friction. I’m also going to adjust the main wheels outward a bit so there’s no chance that the big long board wheels contact the 2×4 ties at any point. This will reduce bumps and noise and it’ll make the thing faster still.
All told, Lyle and I are thrilled with this coaster. Next week, if we’ve got time, we’re going back to my house to do some testing on The Caution Zone, which is the coaster we built in our yard. So, please stay tuned for that!
Science Never Tasted So Good! In this adventure, Lyle and I made delicious Ice Cream using Liquid Nitrogen as the cooling agent. Liz and Ellie helped with the camera work and production, and the whole thing made for a supercooled backyard science project for the whole family.
CAUTION: Liquid Nitrogen boils at -320 Fahrenheit. That’s really, really cold. So, it’s important to make sure you handle it safely. You’ll need a face mask, cryogenic gloves, and proper project clothes. Be Careful! Okay – Now that that’s out of the way, let’s get on with the fun!
Liquid Nitrogen Ice Cream is made like any other ice cream, except for cooling it down, we pour the Nitrogen directly into the bowl with the other ingredients. Because Nitrogen is an element, when it evaporates, there’s nothing left but cold, delicious ice cream.
Nitrogen is Number 7 on the Periodic Table of Elements. That means it’s got 7 electrons in the two “rings” orbiting its nucleus. Two electrons in the inner ring, and five in the outer. Nitrogen freezes at -346 degrees Fahrenheit, and boils at -320 degrees Fahrenheit. Our atmosphere is made up of about 79% Nitrogen. We breath quite a lot of Nitrogen all day, every day. Nitrogen is colorless and odorless. It’s all around us, and life wouldn’t be possible without it. Awesome fun projects like this wouldn’t be possible without it, either
Here’s our recipe for the Mint Chocolate Chip NitroScream, as Lyle calls it!
Peel and halve the peaches, and heat them up so they're super soft. Use a grill, a toaster oven, or even a propane torch for this. Then, chop the peaches into small dice.
Split and scrape the vanilla bean, saving the husk.
Combine all the other ingredients EXCEPT THE LIQUID NITROGEN, MINT AND CHOCOLATE in a large saucepan and warm over medium heat until it steams but does not boil. A candy thermometer is a great way to do this the right way every time. Bring the mixture to 175 degrees F. Strain and cover with a lid or plastic wrap. Let it cool to room temperature, or place in the refrigerator overnight.
Pour the mixture into a Stainless Steel bowl or the stainless steel bowl of a mixer. WARNING: DO NOT USE GLASS. Start the mixer on the lowest setting, or stir slowly. Slowly add 1 cup of Nitrogen and mix until is completely evaporated.
After the first round of Liquid Nitrogen, add the mint and chocolate shavings.
Continue mixing and adding liquid nitrogen into the mixture, approximately one cup at a time, until the mixture is at the consistency of ice cream.
I caught up with Fritz and Steve from EepyBird.com the other day at Maker Faire 2014, and boy did they have some fun! I got to spend a little time with Steve, who taught me just why Mentos and Diet Coke make such an amazing combination, and we managed to get a pretty good video of the whole thing.
The main thing that makes the whole thing work so well is called nucleation. That’s the process of forming an actual nucleus. Ions, atoms, or molecules arrange in a pattern similar to that of a crystalline solid. Then, the carbon dioxide from the soda collects around that area. Stick your finger in a glass of soda, and the bubbles that attach to your finger are doing it because of nucleation.
Mentos have a lot of surface area, which means lots of bubbles can form on the surface. That’s why they make so much foam. They are also heavy, so Mentos sink to the bottom of the bottle, allowing them to mix with as much carbon dioxide-rich soda as possible.
Say hello to The CrossBow! That’s what we named this new cart. The reason is that the front suspension has a curved steel part right up front, and the steel pipe that runs nearly the length of the cart reminded me of a bow and arrow.
The cart is entirely custom. Every bit of everything, except the wheels, bearings and some of the screws was built by hand by me. I’m incredibly proud of The CrossBow!
Meanwhile, over at Abraham’s house, the track is coming along nicely. The carpentry crew has a little cleaning up to do here and there, and some of the tolerances aren’t quite where they need to be. But, the whole thing was good enough for some pretty great testing, as you can see from the Video above. In another day or two, I’ll post a second video to dig into the details of the walkthrough and some of the design/build features of the CrossBow cart. You’re gonna love that one!
Stay Tuned, and please be sure to Like, Share, Follow, Digg, and Tweet about The CoasterDad Project!
When you do this simple experiment, here’s what’s happening. Your brain is creating a Negative Afterimage. When you stare at the negative image, the photoreceptors, which are the parts of your eyes that “receive light” get overstimulated and fatigued (tired), which causes them to lose sensitivity. In regular situations, you don’t even notice this because the little movements of your eyes keep your cone cells, one of the two kinds of photoreceptors, from getting overstimulated.
But, when you stare at a large image, the tiny movements in your eyes aren’t enough to reduce that overstimulation. So, you start to experience what is known as a negative afterimage. When yo shift your eyes to look at the white box, your overstimulated cone cells keep on sending the image information to your brain. That has the effect of “muting” the colors being transmitted.
Then the photoreceptors that aren’t overstimulated start to send strong signals that are the opposite of the colors you were seeing before. I know, it’s a little confusing. The result is that your brain, wanting to make sense of your world for you, sees these afterimage signals as the opposite colors. A negative of a negative, as it were. This creates a color image of the negative you were staring at.
Here’s to all the men and women who serve our country, and keep us safe. Words like Thank You don’t begin to cover it. Every day, I try to honor all the wonderful people who made me who I am, who make my life what it is today. I try to honor these countless sacrifices and contributions by living the best life I can, by serving those around me, and by earning the amazing gifts I’ve already been given. That’s what “thank you” means to me.
I hope you’ll forgive my keyboard skills. The point of this particular rendition of the Star Spangled Banner is to show what sound looks like. Here’s what’s happening.
The thing with fire coming out of it is called a Ruben’s Tube. Into one end of the tube, we’re pumping propane gas. At the other end of the tube is a speaker, through which the music is played. Along the top of the tube are a few hundred little holes that let the gas out. When the propane leaves the tube, it mixes with air, which makes it flammable. Pure propane, by the way, doesn’t burn at all. It needs air. Somewhere between 3% and 11% mixture. More or less than that and it wont burn at all.
When I play the notes, you’ll see that the flames form at different heights across the tube. That’s because the sound being played into the tube creates areas of different pressure. These are called Standing Waves. The lower the notes, the longer the wave. As you listen to the music, you’ll see that some notes create more pronounced flame patterns, or waves, than others. The Star Spangled Banner is a great song for this kind of demonstration because it covers a really wide range of notes. Plus, it’s patriotic and fun to play, even if your last piano lesson was 30 years ago.
I hope you enjoy the song, the SoundFire Tube, and your memorial day.