As I was driving to school one day, I passed several hot air balloons and thought it might be fun to make a homemade version.
Here’s a couple songs on my playlist for this build (playing one of these while reading this post is highly recommended):
I started with the basket:
I’m using an empty water bottle and tinfoil as fireproofing.
As fuel, I’m using cotton balls soaked in alcohol, but I’m thinking about switching to emergency cooking fuel sold at emergency prep stores.
The balloon is painter’s plastic folded origami-style and taped on the seams.
I folded the plastic top to bottom.
Then, from left to right.
So, the top corner is now the top of the balloon.
Next, I cut and shaped the balloon. *Note, do NOT cut the top even though it will look weird and pointy.
After you unfold it, you’ll see a repeating pattern. Next, you just tape up the seams. Leave 4-6 in slack to tie to the basket.
I used kite string and electrical tape to make loops that I’ll use to tie the bottom of the balloon to. I also attached kite string to the bottom of the basket to keep control of the balloon while flying. An out of control, flying mass of burning plastic would be a bad idea, yeah?
The balloon is a little over 4 feet tall and about 4 feet wide. I filled it with a blowdryer and it looks pretty great. It takes a lot of heat to keep it afloat though, I’m worried cotton balls might not burn hot enough. Next time I’ll use a 6’x6′ square of plastic rather than the 9’x9′ square I used this time.
Turns out the difference between the heat inside the balloon is a major factor in the amount of lift the hot air generates. (see https://www.brisbanehotairballooning.com.au/faqs/education/123-hot-air-balloon-lift.html)
So now I’m just waiting for a calm, cold, windless night to fly it.