Category Archives: 3D Printing

3D Printing & Math in a Classroom

Printrbot 3D printer in classroom
Kids look over the a mini-whistle being printed in their math class.

Last Friday I got to talk about how 3D printers work & demonstrate printing to a class at Tzouanakis intermediate school in Greencastle. A lot of the math skills being learned in 4th and 5th grade math, at least in the current common core curriculum, are used when printing on a 3D printer. Obviously simple length and dimensions are needed and almost all 3D printer software controls are entered using metric dimensions. In contrasting a 3D printer with an ink jet printer (which the kids all have seen) we could bring in how coordinates are used with the printer head so the plastic goes on the right place on the printer bed (some of the kids have already been plotting x and y coordinates on charts).

Cura Software Screen printing whistle
The Cura 3D software screen used to show some of the things taught in 4th and 5th grade math.

There was lots of other things briefly covered related to math & science, including how the software being used (Cura) estimates how much plastic will be used (both length and weight). By having them measure the diameter of the filament used, we worked through calculating the circle’s area and then volume so they could see how much plastic will be used. Some of the kids have been exposed to unit volumes in the current curriculum, and while it was covered pretty rapidly perhaps the rest will remember it when they get that in more depth next year.

We also talked about the temperature settings and how that melted the plastic, asking if the 206 degree setting was hot enough to melt plastic. Some of the children that have been overseas immediately recognized that this was in centigrade rather than degrees F, so we worked through a conversion equation so everyone could realize these were oven like temperatures.

Mrs. McCoy's Tzouanakis Class with their 3D printed whistles
Kids trying out their mini-whistles… outside!!

After printing out a mini-whistle, I then showed them how the scaling function could change the size with a few clicks and re-printed a larger whistle. Most of the kids guessed correctly that the larger whistle would have a lower sound/pitch, but there was a lot of looking around to see who was raising their hand when they were asked to vote.

A special thanks to Mrs. McCoy for allowing me to come into her classroom for the printing demonstration. The class was scheduled at the end of the day & each of them got a 3D printed mini-whistle. Hopefully their parents are still speaking to me! I certainly hadn’t realized how loud 28 small plastic whistles blown at the same time would be!! You can listen to it in a video here

Making Persistence

raspberry pi case 3D print
3D printed Raspberry Pi camera case that will be used with Octoprint to monitor/control a 3D printer.

One of the things that makers (and good entrepreneurs) have is persistence. It’s a basic part of the DIY (Do It Yourself) culture, you don’t give up even if you don’t know exactly how to do it. A fair amount of uncertainty and vagueness are expected, you simply believe it will work out in the end. Even if it doesn’t work the first time. Or the second.

I’ve been going through a lot of that in building a 3D printer the last few months. Picked a kit versus a fully assembled so I’d learn more about how they work. But have to admit, there has been several times that I’ve felt like throwing in the towel. Even with good documentation it’s hard to cover every possible wrong step. And the technology is still… ‘developing’…

What has been a key has the online 3D printer community. When I had a problem with a z-axis nut that wouldn’t fit, others with the problem confirmed that grinding off some metal would fix it. When my first prints had problems and I posted a picture of the problem, I had detailed suggestions on what to change in the software parameters within 30 minutes of my post!

But writing out detailed questions and getting answers still takes more time than talking in person. While I love the sheer number of people you can reach with an online post, it still has some disadvantages versus talking to an expert in person or sharing what you’ve learned with others directly.

A local community of makers could help that. There are at least 3 other groups of people here in Greencastle using 3D printers that I know of and I believe there are more. We need to create opportunities for people to share their experiences and help the knowledgebase to grow.

Castlemakers as a group is exploring some events to do exactly that, including a local competition for 3D printers and designers. If you have an interesting in helping, please contact Chris directly or send an email to .


Making in Art

In a recent trip down to Berea, KY I got to see firsthand how the Arts community is starting to converge with the making culture, kind of putting the STEAM (Science, Technology, Engineering Arts, Math) in to STEM!

Artisan using a loom to create fabric with a weave/pattern for the upcoming Christmas season. The control mechanism is fairly complex that allows the flying shuttle and the proper heddles in place.
Artisan using a loom to create fabric with a weave/pattern for the upcoming Christmas season. There is a fairly complex mechanism that moves the flying shuttle and puts the proper heddles in place at the right time.

Berea of course has been known for years as an artisan center and you can see the maker culture/impact there even if it is not always called that. Artists have always been makers at heart, you only have to watch the mechanics of someone weaving fabric or tapestry in a large loom or listen to someone  describing the pickling process when silver soldering a necklace or bracelet to realize there’s a fair amount of STEM that artists can use in their craft. One studio I was in had a period table of the elements on the wall next to their casting area.

One studio creates pewter casting molds using table-top CNC machines and 3D printers.
One studio in Berea creates pewter casting molds using table-top CNC machines and 3D printers.

What I found interesting was how the personal fabrication tools that makers are embracing are being used by artists, and vice-versa. Smaller CNC machines, laser cutters, and 3D printers are all being used to create art, but then anyone that’s been to a Maker Faire knows/has seen that already. That jewelry or napkin holder may be made with something that could be built in makerspace!

There’s a core group of Castlemakers that are working towards creating a more permanent place, a makerspace, for us to create things. And to hold some of the parts and fabrication tools we’ve started collecting, including some best shared, that would allow people to make things – young and old. If you’re interested in helping, send us an email.

If you’re interested in finding out more about making your own artwork, Berea now has a series of art making workshops that you can sign up for. The biggest is their Festival of Learnshops in July, but there’s an upcoming Holiday series called Make It, Take It, Give It that starts the end of November which looks to be really good also.

3D Printers

Smaller RepRap style 3D printer that 3D Parts Manufacturing is offering
Smaller RepRap style 3D printer that 3D Parts Manufacturing is offering.

Many makers have or use a 3D printer. I’m sure there are some here in Putnam County already, but I’d like to see a publicly available one. I’m personally building a 3D SLA printer with some help from some other folks, but would love to connect with other folks near Greencastle that have a 3D printer. Respond to this post or send me an email if you have one. There’s a certain amount of learning in making these work & we can build our skills/knowledge together.

Last week I was able to visit 3D Parts Manufacturing in Indianapolis to see their operation. Neat operation and Kim Brand is doing some real interesting things around 3D printing. If you just look at their website you’d get the impression that they’re mainly involved with the high end 3D printers, and they certainly have those, but they’re also working on creating a program for middle school kids that includes a 3D printer, support, and the lessons to go with it. An IBJ reporter was there the morning I visited and an article on what they’re doing just came out in this week’s Indianapolis Business Journal. I’m hoping to get Kim over here to Greencastle later this year.

There are several different types of 3D printers, explaining some of the nomenclature can help you understand those types.

3D printing is an additive process vs. the traditional subtractive machining used with CNC, lathes, and many other traditional fabrication tools. One of the real breakthroughs in more affordable printers was the open source printers that first started appearing in 2005. Many of these were based on the RepRap design goal to create a machine that could print most of its parts. The RepRap based designs, and most current printers less than $1000, use Fused Filament Fabrication (FFF) which extrudes a thermoplastic. But other options are starting to appear including some lower cost Stereolithography (SLA) designs. SLA has traditionally been one of the more expensive 3D printing methods because of the material cost and laser control. I’ll write something on low cost 3D printing methods and the equipment we’re looking at for Castlemakers in a future note.