How to Make a Steampunk Submarine

I love making models. Any excuse to build one will do. Sometimes, it’s really tough to draw something straight out of my imagination, and seeing it in real life can make all the difference.

A shark model to get the fins right? Terrific.

A clay mock-up of the West children to nail that cave lighting? I’m on it.

A steam-powered octopus submarine to appear in several illustrations for the next Expeditioners book?? Sign. Me. Up.

The moment Sarah Stewart Taylor told me there’d be an octopus submarine in The Expeditioners and the Secret of King Triton’s Lair, three absolute certainties popped into my head before I’d even read the manuscript:

1) Something as awesome as an octopus sub had to go on the cover. No question.

2) I’d have to make a model of it to have any hope of drawing it consistently from illustration to illustration. A submarine—which is both round with flat parts and tapers toward the stern—is hard enough to draw accurately when it’s normal, but an octopus-shaped submarine—with moveable legs and arms—would be pretty impossible without some sort of three-dimensional model to hold, turn, light, and photograph in my studio.

and, 3) Above all, fictitious or not, I knew that I wanted the Expeditioners’ submarine to look like it really worked. That meant designing and building the model as if it were a real ship, including the additional design challenge of building a model with moving-parts that both resembled an octopus and could plausibly accommodate an engine, two hatches, and four seats for Kit, Suki, Zander, and MK.

But how do you translate an octopus’s flesh into metal? And is there a precedent for steam-powered submarines in the real world?

On the surface, steam power isn’t the most logical choice for a submarine engine. A steam engine is a combustion engine, which means it burns fuel to heat water to the point of vaporization, generating pressure (and power). But burning consumes oxygen, so in an underwater environment that same power source could potentially use up all the oxygen in the submarine and suffocate the passengers!

Luckily for my design (and my research-obsessed brain), I discovered at least two real-world precedents for steam-powered submarines to refer to:

The first was the 1913 British K-class submarine, used by the Royal Navy during World War I. Unfortunately for Her Royal Majesty’s sailors, these boats were nicknamed the “Kalamity Class” for their high number of sinking accidents.

The second precedent felt much more promising to borrow for our octo-sub. The Ictineo II was built in 1867 by inventor Narcis Monturiol, who designed a chemical furnace that boiled water using the reaction between potassium chlorate, zinc, and maganese dioxide. And, best of all, it gave off a by-product of oxygen! The furnace made oxygen instead of burning it. Our octo-sub was now in business!

A chemical furnace that wouldn’t kill Sarah’s cast eased both my design problems and my mind. So, after my ideas passed the inspection of my engineering dad, I estimated the relative size of the engine to the characters and then began tackling the exterior design.

I’ve been a huge fan of Disney’s 20,000 Leagues Under the Sea since I was a kid, so their version of Nemo’s Nautilus (which ran on nuclear power, by the way) seemed like a great first stop for architectural inspiration. But, of course, the Nautilus didn’t have legs. Eight really is a lot of legs to deal with. That would be my next hurdle.

In the story of The Expeditioners and the Secret of King Triton’s Lair, the submarine has a lot of TOP SECRET functions that require the legs to move individually. If this were a real ship, these working legs would need to fold into themselves to generate the least amount of drag in the water. Otherwise, it would be a really cool looking ship, but slooooow. No good.

So, after lots of trial and error with paper cutouts and brads, one design stood out from the rest:

Here was a leg that could fold into itself, tuck back behind the ship to reduce drag, and support the submarine while “standing” on the ocean floor. I tweaked the shape to look more octopus-like, then scanned the paper pieces into Photoshop and began a final architectural plan for each part of the ship.

At long last, it was time to build the actual model. I printed out each side of the body and each side of each leg, glued the printouts onto cereal boxes, and then carefully cut out all the pieces. What followed was really one building disaster after another; at first, none of my methods seemed to work.

There were several rounds of glue-gunning, clay modeling, cork cutting, and paper-mache layering, not to mention numerous trips to the hardware store. I had to cut the model apart and rebuild it many times, because it wouldn’t stand up on its own, or it wasn’t symmetrical, or the cockpit head was getting in the way of the leg movement and rotation. There was also a lot of frustration around making the windshield stay in the correct, oblong shape. Plastic bottles and water balloons were not the right solution.

In the end it all came together, and I’m so pleased with how the final model turned out! I could not have done all of the submarine drawings in the book without it.

The Expeditioners and the Secret of King Triton’s Lair hits stores on September 23^rd—if you loved the first book, you’ll love the second even more! Pre-order your copy from your favorite bookstore or online today, and thanks for reading!

*Photo and plans of the Ictineo II are from Wikipedia, made available under the Creative Commons Universal Public Domain Dedication.

*Image of the Nautilus ship by WikiFred at the English language Wikipedia [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0/)], via Wikimedia Commons