Can I cram it all in?

As with any model boat, work starts on the Ark by taking a perfectly watertight hull, and making holes in it.

The rudder is easy enough - drill a hole, ream it out, screw the rudder tube in place. For a change, I haven't needed to mess with the length of this as the hull is so thick at this point it more then covers the plain section of the tube.

Fitting the prop tube is a little tougher. I've elected to use a 60mm plastic propeller for a few reasons:

• It's bright red and matches the hull (sort of)
• I had it to hand
• I like the cartoony idea of an oversize prop under this boat

The practical upshot is that the shaft has to be inclined quite steeply.

I don't see this as an issue. The short hull means little space for a motor but fitting it at an angle will help. OK, the drive won't be as efficient, but this is a pootling around boat so who cares?

One challenge will be shortening the shaft. 6 inch is the shortest one available and I reckon I need half that. Time to get the tube cutter out!