Up and Under

Brian went back up to the University of North Georgia to play a match agains Kennesaw State University. So he got to play with guys he’s practiced with recently (UNG) and guys that he played with last year (KSU). We was wearing the #15 and played fullback for a good part of the game, switch with his coach, Cam wearing the #10, on defense when kicking might be a thing (since Cam is the better kicker). But he also played a bit of 9 and generally went where needed.

This was a nice little up and under kick. He wasn’t set far back, and the defender is on top of his just as soon as he gets the ball. But he manages to get a short high kick away. The he has to fight and weave his way through a crowd to get under the ball. He’s got just a bit of a bobble in contact as he makes the catch… but breaks through and runs in his own kick for the try. Nicely done!

Soldering

When it comes to electronics, soldering is essential. You can only go so far until you have mastered learned how to solder at lease little. More essential than a screw driver, is the soldering iron. Remember: If it smells like chicken, you’re holding it wrong.

HoverBoard

Girl on riding hover board sitting lawn chair holding leaf blow down with speed motion blur
Isabel is off to the races

There is nothing quite like handing kids a jigsaw and a large sheet a plywood. But less than an hour later, with all fingers in tack, they were racing around on their very own hoverboard. Powered by a cheap electric leaf blower, the hoverboard would slide along smooth concrete surface of the warehouse with almost not friction. It’s a super easy project requiring very few special tools, and not a lot of time.

Non-Newtonian fluids

It helps to know what a Newtonian fluid is before you start thinking about non-Newtonian fluids.  Conveniently, just about every fluid you can think of is Newtonian.  When you push on a fluid, it moves out of the way.  Some move fast, some move slow (this is quantified as viscosity), but when a fluid seizes up and stops,,when it becomes like a solid in response… That goes against Newton!

Obleck bounding on a speaker
Non-Newtowning fluids are better with food coloring

Perhaps the most common non Newtonian fluid people run across [foreshadowing] is cornstarch and water. It’s used to thicken gravy and other sauces (because of viscosity). But when making gravy, you are cautioned to mix the corn starch in cold water first and then add that to your hot liquid that needs to be thickened to avoid clumps. This is because the corn starch on the outside will mix with water first and be agitated (pressed on) by the hot liquid and turn solid, preventing even distribution of the inner cornstarch. But if you mix it with child water first all of the corn starch will be able to mix with the hot water.

5 kids mixing conrstarch and water by hand in a 15 gallon bucket
A hands-on experience

So we mixed it 50lbs bag of corn starch with water, and learned that if you put water into cornstarch it will mix on the surface, and further attempts to mix in more water will cause the outer cornstarch solution to turn solid. Preventing further mixing…. Much like cornstarch dumped directly into hot water. The right way to mix large batches is to add the corn starch slowly into water until the desired thickness is achieved.

You can then put that on a speaker and play a time of just the right frequency to see the corn starch turn solid, be thrown in the air and turn liquid again on the way down

Or you can jump in a big tub of it and see if you can start running before you begin to sink. It’s harder than it looks.

Or you can cut to the chase and just build a trough that you can run across… Or stop and sink into.

Making liquid dance on a speaker is pretty cool, and visually memorizing, but hands on (or feet in) is really the best way to experience and believe in the properties of Non Newtonian fluids.

kids gather around and playing with obleck in a speaker

No matter what you do though, make sure you leave lots of time for cleanup.

Solar Eclipse in Clemson

Enlarge Cereal Box Solar Eclipse viewer
Joshua’s solar eclipse view

We travelled to Clemson for the total solar eclipse. We threw a few simple, random building materials I the car as we we’re heading out. And when we got there we had a little bit of time… So we made a cereal box viewer, sans the cereal box… And way better. Josh gave lots of demos and explained how it worked and some of the more interesting properties. So much so that we were interviewed for and included in a book!

One of the neat things about the book was that Marie Harris, one of our favorite librarians from “The Loft” (a cool teen only space at Imaginon – the Children’s Library) in Charlotte – send me an email after she read the book. We’re quoted talking about Baily’s Beads which was truly the most amazing thing that I got to see being in totality.

Compressed Air Rocket Launchers

5 or more compressed air rockets launchers on a table
We’ve made a few compressed air rocket launchers through the years

When it comes to making your own launcher, it’s hard for me to do much better than the Instructable I put together a few years back.

If on the other hand you are looking to make rockets, fast and furious, check on my video on YouTube is the place to be. There is also another video where I make a high pressure rocket in about 2 minutes.

Compressed Air Rockets and Launchers at MakerSpace Charlotte
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