Earlier in the week, I baked off four 9x13 marble layer cakes and froze them, but only ended up using 3. I used Duncan Hines Supreme mixes, and spiffied them up a bit with pudding mix, milk instead of water and an extra egg - moist and delicious! (Thanks for the tip, Anne!) Baking the cakes early and freezing them was a must - being partially frozen made them easier to stack and carve, and easier to frost. I didn't notice any difference in the taste or texture.
I started with 2 layers - leveled them off then began building up the ship. The bottom layer is one whole 9x13 and an additional 3 inches from the second layer cake. Before assembling, we whipped up a big old batch of chocolate buttercream and a smaller vanilla batch for piping work.
I used the remaining bits of the second and third layers to build up the bow and stern portions. I always stack cakes with the cut-side down to make frosting them a bit easier. Less crumbs that way.
An additional cut piece on the stern end to give some height and another layer of deck - more "pirate-ship-like" in my opinion. I'm sure there is a technical term for it, but my research only carried me so far.
Once the layers were stacked and fairly even, I used two dowels in the stern end to keep the ship from falling over. The front was fairly sturdy, so I skipped them. I carved the front end into the bow shape with a smaller serrated knife. Semi-frozen cake very helpful here.
This is the crumb-coat or, as my good friend* Buddy Valastro says, it's "dirty iced". I used a small offset spatula to make the grooves in what would be the decks - I wanted it to look different than the sides.
I used a basketweave tip to pipe on the ship's planking for a wood look, varying the length of the piping to mimic the wood. Covered the entire outside of the ship this way.
This is the finished version at the party. I added sails made from plain old paper and chopsticks. The pirate flag was a serendipitous Joann's Fabrics clearance bin find for 10 whole cents the week before the party. If not for the little wooden flag, I would have just printed out a jolly roger from the good ol' internet. Add a few pirate figurines, a "4" candle and some icy blue buttercream waves and Voila! or Ahoy! or Whatever! = Pirate Ship Birthday Cake!!!
*I do not personally know Buddy Valastro. I do love his show, though. That makes us "friends" right?