CNC Machine

I made my own CNC or Computer Numerical Control machine. I started with nothing but a set of plans I downloaded from the internet and only a vague idea of what it was. There was no kit for the parts – I had to buy every nut, bolt, and piece of wood myself. I spend an embarrassing amount of time building the bed which looked suspiciously like a pallet. The sad part was when I was finally finished (mostly) – tightened the last nut… I wasn’t even ready to use it. Someone made the first cut because I didn’t know how.



Carbonated fruit? Of course! But if you happen to break a bunch of glass vessels in the process of pressurizing the C02 and you want to research other pressure vessels – like an actual pressure cooker, to see how much pressure they can hold before they explode… Don’t do that search ahead of the Boston Marathon bombing. Outside of that, you should be fine.

Basically we dropped dry ice into a container full of fruit and sealed it. The dry ice (solid CO2) sublimated (turned to gas from a solid, skipping the whole liquid phase – that’s why they call it _dry_ ice). Since the gaseous from of C02 wants to spread out, but can’t… the pressure increases. And with no where else to go, if forces its way into the fruit. Emerging as effervescent froot!


I tried to take a few pictures along the way. Mot but not all are mine. Endless thanks to all the other people that took pictures and shared them.

Some of the pictures are on Google Photos, Flicker, and other photo sharing sites. Some are perhaps lost forever (looking at you Google Plus).

The age of the pictures reflect the journey through time and places.

  • First is mostly family only
    • Atlanta
    • Charlotte
  • Hackerspace Charlotte (HSC) in NoDa (between the railroad tracks_
  • Community outreach via HSC
    • Discovery Place – [mostly] children’s science museum
    • Imaginon – CharMeck Children’s Library
    • CharMeck Library – mostly the main branch
  • Hackerspace Charlotte at “The Spot
  • Charlotte Junior Rugby Association (CJRA)
  • Makerspace Charlotte (the great divide – HSC banned kids… seriously?!)
    • Clairborne Prosthetics
    • 100 Gardens
      • The craziest summer camp ever!
  • Atlanta again
    • Gyomo ( cyber security startup )
    • Alpharetta Rugby
    • East Cobb Rugby
    • Roswell Rugby
  • Makerspace Charlotte (the great divide – HSC banned kids… seriously?!)
    • The iterim space
  • The Netherlands

All of which to say, photos are all over the place and in various different collections. For the collections I have control over, I tried to group/categorize them and like to those photo groups appropriately above. If I couldn’t link to a group of photos it’s probably a link to the best website I could find. And if there are two or more links on one bullet point, each link probably goes to each bucket or site I could find.


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 viewer

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.


After seeing a small artistic tree made with polished stones, I was inspired to create one with LED as a nightlight for my daughter. The trunk and branches are made with enameled (magnet) wire. The LEDs are automatic rotating RGB so they change colors over time. The first tree used “fast blink” LEDs which change color about once per second, which looking back at it (and when looking directly at it) was somewhat seizure inducing. Later refinements used “slow blink” RGB LEDs that slowly changed from one color to the next over about 5-10 seconds. Interestingly, when powered on, all the LEDs go through the same color shift pattern, but fairly quickly small differences in timing cause the LEDs to be all different colors at all different places in the sequence. It’s quite soothing and almost difficult to tell that they are changing at all.

The hardest part of this project is tinning the magnet wire. Each end of the wire must be stripped of the enamel coating and soldered before (easier) or after (harder) twisting the trunk/branches together. Using two different colors of enameled wire make it easy to discern the positive and negative leads to solder to the LEDs.

The Tree was powered by a 5V 0.5A USB power block for charging cell phones – we called them marshmallows. The real trick there was cutting the USB cord and attaching the tiny little wires to the base of the tree.

In spite of may people wanted a tree, few people made them due to the time involved. But it was a great “learn to solder” project because of so many solder joints required, the low quality required, and the fast feedback loop. We soldered this kit “hot” – the power was connected the whole time you were soldering, so you knew if it was working or if you made a mistake right away. That’s a much better way to learn to solder.

With all that potential Ben and Mike create a much smaller scale kit that was immediately popular. The tree could be built in a single visit to the Makerspace and enjoyed at home that very night. The problem was that it to a lot of prep work to build a kit! The tinning was a pain – I purchased a solder pot, and we even bought an electric enameled wire stripper (if results with thinner wire).

There are a lot more pictures over in google photos

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