Category Archives: Making

Liquid Nitrogen – August Meeting

What happens when you hit a marshmallow frozen at -196°C.
What happens when you hit a marshmallow frozen at -196C.

At our August 9th meeting we covered the Water Balloon Challenge, which is now up to 8 groups. Details on our project page, but they seem to be performing so well that we concluded that the Greencastle Farmer’s Market display in early September should be a demo, not the actual competition, since the Greencastle square may not be large enough!

What happens when you insert a balloon into liquid nitrogen. There's also a video where you see it shrink and then expand.
A balloon being shrunk by inserting into liquid nitrogen before re-expanding, the record was 4 times for one balloon!

For our ‘show & tell’ portion Chris brought liquid nitrogen in a dewar for experiments. After explaining describing liquid nitrogen and where it comes from, we poured the -196°C (-320°F) liquid over the marshmallows that Alice had brought in. We also froze a banana to drive nails into a piece of wood and then tried lots of things that kids and the adults suggested. Some that worked and some that didn’t!

A raw egg that was frozen first with liquid nitrogen then melted down during the meeting back into a normal uncooked egg.
A raw egg that was frozen first in the shell with liquid nitrogen then thawed down during the meeting back into a normal uncooked egg.

Freezing balloons was a big hit, the kids had tons of questions which you can hear and see in the balloon video that Brian H. took. For the coin collectors there, we showed how older copper pennies are more malleable at minus 200 degrees Celsius than the new copper plated zinc pennies – which shatter after hitting them with a hammer!

There’s another good regional event for science in Bloomington on 8/29, Makevention, along with some other events on our events page. Last year we took one of the shovercraft (shoveable hovercraft) to the Bloomington event and did demonstrations. It’s well worth the trip if even to just to look at what other people are doing.

Since we’re starting to look for projects after the Water Balloon Challenge, I can’t help but mention the Lexus created hoverboard that uses liquid nitrogen. I just watched a video (long version) on it, sort of outdid our shovercraft but a lot of more engineering in that design. Now that would be an awesome next project!

July 2015 Castlemakers Meeting

Alice tries flying Isaac's drone that he brought to the meeting.
Alice tries flying Isaac’s drone that he brought to the meeting.

At our July 26th meeting we shared and discussed the upcoming Water Balloon Challenge in August. Interested kids & adults signed up and there are 5 preliminary teams creating something to launch a 2″ diameter water balloon farther than you can throw it – but there are several more rumored to be forming and folks can join in at any time.

Some of the kids afterwards viewed the drone videos from earlier in the day. You can see one of them on our Youtube channel.
Some of the kids afterwards viewed the drone videos from earlier in the day. You can see one of them on our Youtube channel.

Special thanks to Isaac & Matt who brought their new drone for the sharing portion of the meeting. All the kids that wanted to try it got to fly it. We also learned that one is very durable!

June 2015 Castlemakers Meeting

Preloading the Water Balloon Cannon with air pressure. Meanwhile some kids make water balloon for launching from the rubber tubing launcher.
Preloading the Water Balloon Cannon with air pressure. Meanwhile some kids make water balloon for launching from the rubber tubing launcher on the right.
Water Balloon Air Cannon Launch
One of the ‘bad’ shots where balloon busted upon launch. If you look closely at this photo you can see the water squirting out the back of the balloon in the air, apparently it was not tied tightly!

In our June meeting we discussed different water related projects and tried different water balloon launchers to learn how they worked. Besides the classic surgical tubing slingshot method of shooting water balloons that Boyd, Elise, & Jim brought, we also looked at a pressurized water cannon that Rebecca & Chris built.

The water cannon, pictured to the right, was made from 2” pvc pipe and then used a bicycle valve stem to pressurize the main chamber. By opening the 2” pvc valve after pressuring, the burst of air propelled the water balloon… well initially 40-50 feet in prototype testing. But by correcting the launch angle with the help of the other folks there, a smaller volume of water for the cushion, and increasing the pressure with the bicycle pump we discovered that it easily went into the next city block.  Not sure exactly how far it will go since it was hitting tree branches down the street.

After making sure anyone that wanted to (and a few that didn’t) were drenched, we decided that this would be our next build that we could show off at the Greencastle Farmer’s Market. More details soon!

Making Ideas from Art

While you hear a lot about STEM, many in the Making community talk a  lot about STEAM (Science Technology Engineering Art Math). Attend a Maker Faire or look at any Make magazine and you can’t help but notice how many artistic creations (how about an electric giraffe) are being made. Many of the same things shown at the bigger Maker Faires have also made appearances at Burning Man, arguably one of the most creative artistic community rituals that I’ve encountered.

Clay Sculpture by David Katz at Peeler
One of the traveling exhibits at Peeler Gallery.  This  temporary clay sculpture in 2014 by David Katz seemed to be attached to the walls.

A good Putnam County art resource is the Peeler Art Gallery on the DePauw campus. A lot of people forget about it and it’s open to the public for free. One of the current exhibits has some Andy Warhol photos and prints, but it changes every few months. If you look at this exhibit link read it very closely, summer hours are reduced from regular hours during the school year.  It’s not a huge gallery like IMA, but I’m always amazed at the quality of the exhibits at Peeler.

Amateur Radio Convention

Dayton Hamvention Slow Scan Video Transmission from Balloon at 1000 feet
Dayton Hamvention Slow Scan Video Transmission from Balloon at 1000 feet

It’s that time of year again when amateur radio operators, descend upon Dayton, Ohio for the annual Hamvention. This weekend (May 15-17th) in and around Hara Arena 25,000 people or so will be there to learn things at seminars, buy, and swap things. This is the biggest event in the Midwest for folks interested in making anything electronic – although the focus of the event is on amateur radio. But if you’re interested in making things, especially electronics, someone will be there selling what you need (or what you want!). I’ve seen everything from electronic kits to build almost anything to Geiger counters, it’s an amazing gawkfest that even includes some military surplus (I remember the collapsible towers were a big item, literally, several years ago).

While you’re there it may be worth a stop at Mendelson’s Surplus in downtown Dayton to check out the 6 floors of surplus ‘stuff’ in their main building (their website doesn’t do the place justice). And of course the USAF Air Force Museum, which I’ve written about earlier, is a great stop to make it an awesome STEM weekend – that’s worth a trip on it’s own.

This Friday we’ll be doing a 3D printer demo for a class at Tzouanakis intermediate school in Greencastle to show them how math is used in making 3D models and prints.  Will also be bringing the Printrbot printer to our next general Castlemakers meeting, which is being set up for late May.

Device Un-making

Castlemaker youth disassemble things.
Some of the devices disassembled Sunday afternoon. The speaker was popular for the magnets & crossover network (“Looks cool!”), but what got early attention was the VCR guts.

Last Sunday afternoon we had a winter (indoor) version of our ‘un-making’ events. Thanks to folks that brought things: the VCR was a huge hit for the motors, gears and moving mechanisms inside and was the main star until the LCD TV showed up! We gained lots of new motors, gears, lasers, & magnets for future projects.

Disassembling a flat panel TV.
The LCD TV that Brian brought was a huge hit.
Cuisinart Chopping
Sometimes you just have to use a hammer…

I was a bit surprised in all the interest in the circuit boards. Several kids starting using pliers and cutters to get capacitors, coils, and heat sinks off – it quickly spread from there (hope everyone checked pockets before the wash!). Found a soldering iron, which was a hit, but next time we’ll bring desoldering tools and more soldering irons. With the obvious interest in (de)soldering and the questions they asked, we’ll definitely do some soldering/electronics in a future session.

We’ve already gotten an offer for a barcode scanner (great laser in those!) and with a few more circuit boards to tear apart, so we’ll have another un-making session soon. Plus they only tore apart one speaker and with warmer weather coming up, I’m thinking we need to make a garden hose/ speaker water stream reverser

Indoor Castle(un)maker Meeting

things that we can tear apart to see what's inside
Come on, admit it!! You’ve always wanted to know what’s inside this stuff… and at our next meeting you can find out!

For our March 8th meeting we’ll be dismantling DVD players & chopping up Cuisinarts. Goal is to find out what’s inside electronic & mechanical devices, toys, and appliances.

We’ll be meeting at 605 Crown Street on Sunday March 8th at 2pm. Bring anything that you have a burning desire to find out how it’s made. Or to destroy (“deconstruct” for you food network folks out there).

Anyone is welcome to join us!

Note: 3/1 meeting has been cancelled due to the snow.

Brushbot Build

Write
Some of the kids try to figure out the effects of toothbrush bristles, we had 3 different designs and a few added toothpick stabilizers. Several tried 2 vibrating motors and different sized batteries, which could change the Brushbot’s path and speed.

Our Brushbot build this last Sunday turned out well. This is a popular kids project, to the point now where you can even buy kits to make them. We did it the old fashioned way with a toothbrush, pager motor, battery and double-sided tape.  Thanks to Dollar Tree and a bulk order of motors from China, they cost less than $1/piece and many of the kids made them with their own toothbrush!

testing brushbots
An old hexbug track made a good testing course for the Brushbots, although several kids also used notebooks and other obstacles on a large flat table to make a track to test different Brushbot configurations.

If you’re like many parents looking for summer opportunities for your kids, this coming Saturday February 21rst, the 26th Annual Summer Camp Fair will be going on from 11-3 in Indianapolis at the Fashion Mall. I try to keep the events page updated with other regional STEM opportunities, if you hear of something you feel others would be interested in let me know.

Also a few of the adults have started building a Robobrrd, a felt-covered interactive robotic bird made of popsicle sticks that uses an arduino micro-controller. At this point it’s still for adults (or older kids) as we figure out how it could best be made by the larger group. Feel free to join us, you’ll be helping other kids down the road. We’re meeting on Tuesday nights at 7 pm, 605 Crown Street at least through March. Again you can always check the events page.

Brushbot Meeting

Brushbot prototype
Brushbot prototype for this Sunday’s build project. Links on how to make them and other modification tips are on our Robotics page.

This Sunday we’ll be making Brushbots using a toothbrush, vibrating pager motors, and a battery. We’ll have a small racetrack to test them, so be thinking about how they can be modified to be more stable along with what kind of bristles would work best and how to steer them.

A very short video of the prototype in action you can view here.

Anyone is welcome to join us, we’ll be meeting at 605 Crown Street at 2 pm on Sunday February 15th.

January Meeting Update

Henry's solar car gets ready to take on the Cubelet built robot. Rebecca shows Cam how the sensor on the back causes it to run away from your hand.
Henry’s solar car gets ready to take on the Cubelet robot. Rebecca shows Cam how the sensor on the back causes it to run away from your hand.

At our first meeting of 2015, the kids brought in things they got or made over the holidays. There was a pretty wide range – from Ryan’s “Cool Circuits” and Boyd’s Tinker Crate (creative building/experimental kit in-a-box that comes monthly) to an owl pellet (no, Eli didn’t ‘make’ that!). Very encouraging seeing all of the other STEM related things they brought and all seemed to have a great time showing them off and trying them out.

We talked about some upcoming projects: Brushbot parts are on the way, watched part of a short demo reel on Robobrrd, and discussed a couple of different paper air rocket launcher options we could build. Based on the votes we’ll try to do both of the latter two, but both are still early in the planning stages.

Lego Robotic Catapult
Clay demonstrates the Lego catapult that he and his dad built while Alice, who built the wooden Ferris wheel, looks on. The catapult uses a Lego Mindstorm controller to voice activate projectiles, which were seen flying around the room frequently.

We’re going to prototype the Robobrrd first, it looks like fun project that could involve both young and older kids. It’s a robotic bird made out of popsicle/craft sticks, felt, glue, servos, and controlled by an Arduino controller – there’s lots of options and a good open-source community behind it. Several adults (and a DePauw student that’s volunteered) will be building the prototype on Tuesday evenings. Let Chris know if you’d like to participate or help.

We also briefly discussed the catapult build and developing a more regular schedule given the problems last month of finding a regular time. For now we’re going to meet on Sunday afternoons at 2 pm, working on a project every 2 weeks and a more general meeting once a month. Our next meeting will be February 8th and will be either the Brushbot build or work on the big trebuchet. After the meeting most of us walked down to the Brickmania  Lego event at City Hall.