The one with all the cows.

This was my first design. As you can see, the otters, led by otter food, run over two cogs, one of which powers the time machine, the other one launches timey-wimey radiation at a clock, which turns the box into a time machine.

This design, I have decided, is a bit impractical- the time-travelling cog only needs to be turned once, and many otters would be needed to keep the electricity going.

1: Otter platform
2: Food
3: Time-travelling clock
4. Wheels in timey wimey liquid
Ace Jon suggested some changes for a second design: Two wheels sitting in a pool of timey-wimey stuff, and food is revealed to the otters making them run over the right cog, moving the timey-wimey liquid the right way to go a certain way in time. This proves that Ace Jon has absolutley no idea how time travel works, as that would only cause nearby clocks to go backwards or forwards 24 hours... maybe 48. But since they'd probably still be hung there in that time, it'd cause a big boom thing. Which is bad.

1: Giant otter on a trapdoor above a big wheel.
2: Timey-Wimey radiation projector.
3: Time machine.
4: Me waiting for tea.
5: Bigger-on-the-inside generator.
6: (at the top) electricity generator.
My own second design features a single, very large otter, which is dropped onto a waterwheel to send a sudden burst of timey wimey stuff at the time machine, which is a lot more eco-friendly. The otters for electricity are inside the actual time machine- a small team are used to make the "bigger on the inside" generator work, and the rest are there to get electricity to, among other things, make the tea.

So, with these plans, I shall finally be able to drink tea with Dinosaurs!