It’s winter, and in some places that means the beginning of snowball-fight season. If you’re going to win a snow battle, you’ve got to have a snow fort. Here’s how to make the best one. It will withstand the craftiest of assaults. It may even be bullet-proof.
First, you need the right kind of snow. It’s got to have some moisture in it—super powdery stuff isn’t great. What you want is the kind that sticks together under pressure. Test it by balling some up in your hand and seeing if it sticks.
Then, you need to lay out your fort. Figure out how big it is and how much building material you’ll need. Okay, now you can start building. Snow bricks are key. Here’s the Art of Manliness on how to make them:
You have a few options when making snow bricks. The first method involves rolling big snowballs as if you were going to make a snowman. This method requires no outside tools, just your hands and a strong back. Another option is to form bricks using an empty cooler or plastic tub. Just pack as much snow as you can in the cooler, turn it upside down, and presto! Instant snow brick. I find this method much more efficient than the snowball rolling method.
Only amateurs build these snow bricks out of snow. Real snow fort builders know the secret. Rather than just using snow, you make those blocks out of pykrete. Wired explains:
Pykrete is a composite material made of a mixture of wood pulp and ice. Named for its inventor Geoffrey Pyke, pykrete was an experimental material developed during the mad science heyday of World War II.
At a time when steel was starting to run into short supply, Pyke looked at ice, a material that can be formed for a fraction of the energy cost of steel, as a potential building tool. Early experiments ran into problems — ice is prone to being brittle — but they came across research that showed that if you mixed in cellulose with pure water, that the resulting stuff, when frozen, turned out to be quite durable.
When they say durable, they don’t just mean “will withstand a few teenagers throwing snowballs at you.” Pykrete is so durable that it can stand up to bullets. That’s right—it’s bullet proof.
Here’s how you make pykrete at home, according to some dudes on the internet:
I’m making pykrete in milk and orange juice cartons. They hold 64 ounces, so 9 ounces of sawdust is about 14% by weight. I weighed the carton — 2 ounces — and set the balance to 11 ounces. I had to keep mashing down the sawdust to get the balance up to 11 ounces. Then I added water. There was room for 7 cups in addition to the sawdust.
You’ve made your bricks out of Pykrete, and you’re back to assembling your snow fort. You assemble the walls out of your bricks and fill in the gaps with extra snow. Finally, douse the whole thing with some water so it freezes up and stays sturdy.
With that, you’re ready to fight throughout the winters, while your opponents’ forts will constantly need to repair. Good luck, snow warrior.
More from Smithsonian.com: