This week in CEP811 we had to pursue a “thrifting” project. Thrifting is essentially taking junk and making it into something useful. Fortunately, this is already something I do on a fairly regular basis (I’m a cheap, cheap, person), so I already had a bunch of junk lying around that I could use for inspiration. The kicker here, was that we had to combine our junk with our maker tool, which in my case is a 3d printer.
I got to looking around at my junk piles here and there, and came across a box of old computer fans that one of my classes pulled out of a bunch of ancient computers we junked last year. I don’t know a whole lot about electric motors, but they interest me, and I find it hard to throw one away. I thought to myself, there has to be something fun that I could do with these, and they are small, so it shouldn’t take a lot of material to 3d print something to go with them (with 3d printing time and material are big factors in decided what to print). I set out to do some research on the net of what other people have done with old computer fans. Out of all the projects I came across, two interested me most. The first was a computer fan generator, and the second was a computer fan boat. Here are the videos that caught my eye:
Because I lacked the little electronic pieces necessary to complete the generator, I decided to go with the boat, but ordered the parts I needed for the generator, so I can experiment with that later.
Now, looking at the video, you can see that a 3d printer isn’t necessarily needed to complete the project, however, my goal isn’t just to build a boat, it is to learn something about physics in the process. My thought process was to have the students design their boats from the ground up, using the 3d printer when needed to tweak the aerodynamics (aquadynamics?) and their propeller design. Looking through the new middle school science standards, here are some that I thought this project could address:
I began to gather all of my materials. Here is what I needed to complete one boat (this could change depending on your boat design, and what kind of cutting / grinding tools you have available):
- 1 9v battery
- 1 9v battery receptacle
- mini-toggle switch
- plastic bottle
- computer fan
- 3d printer
- pair of scissors
- shoe goo
- wood clamp
- high speed cutting tool (dremel)
- bench grinder
- all purpose snippers
- duct tape
So, the bottle boats were a failure for me. that is not to say a bottle boat couldn’t work. I just didn’t have mine designed correctly. If you had the propeller high enough out of the water, I think it would be fine. Or, like I state in the second video, maybe a paddle boat would be a better design with the fan motor.
My next step was to try out my 3d printed boat model.
As you can see, it actually fared worse than the plastic bottle. The major issue with each of these designs is the weight of the motor, which I obviously didn’t account for enough in my designs.
What lessons did a learn from this whole process? It isn’t as easy as you think to make a fan powered boat. A lot of thought needs to go into the design of the boat as well as propeller. This means that students would mostly likely need time to go through several different iterations of their boat in order to come up with something that works, let alone works good. I’ve found that 3d printing in general takes a lot of trial and error, and lots (and LOTS) of time. This is something that educators need to be painfully aware of when planning their lessons around 3d printing student work. My boat model took over five hours to print; take that times seventy students and…. It’s just something you need to keep in mind.
Personally, I think I would utilize groups for the project, and probably have students build their vessels out of something other than 3d printed plastic. I would save the printing for propeller design, and small pieces needed to attach everything together; pieces that wouldn’t take a lot of time to print. There are lots of lessons to be learned here in the STEM realm, but you would need to allow an appropriate amount of time for students to really work through the problems.
That being said, I feel like a project like this really has some legs. If you took the time to really flesh out all of the mechanics at work here, you could easily cover half a dozen science standards. If you add in the measuring and number work, and have students write about their experiences, I’m sure you could get quite a few math and language arts standards in as well. Throw in some background research on different historical designs of boats in various cultures, and you could very easily run the cross curricular gamut. Bottom line: there is a lot of learning to be had from an experience like this. You just need to make sure that you are leading the students to all of those connections.
Tracking my project with images and videos also allows for some unique learning experiences. It takes the pressure off of my memory, and allows me to elaborate on specific parts of the project that would most likely get lost without some sort of media. I also believe it helps with the transfer of my experience to others, making it a more valuable learning experience for people visiting the blog.