The hull starts to take shape.

DelftSHIP hull design, version 0.4.
DelftSHIP hull design, version 0.4.

On Henry’s advice, the round hull of earlier designs has been discarded in favour of a hard-chined hull. We were originally planning a fibreglass hull from a round mould. The complexities of first producing a “plug” and preparing a mould from the plug, not to mention having to then fibreglass the hull itself, are quite involved. Henry suggested hard chines an 6mm marine ply for the construction, and a light bulb lit up.

By switching to a ply hull, we avoid all of the hassles associated with fibreglass. The down side is each hull has to be built from scratch, but at least we can make tweaks without worrying about committing ourselves to the hull design, once and for all. Once you have a mould, it’s easy to produce lots of hulls. The only requirement is that they all be identical. That’s good and bad, obviously. The hard chines, a feature of using ply strips, will also help the boat in terms of stability. We hope!

Anyway, we still have a few variations on the design yet to come, and then it’s down to cutting ply for the five bulkheads. Yes, five! There will be five, separate, water-tight compartments on the boat. For those of you who are mathematically-inclined, you’ll ask yourself why five compartments and not six? One of the bulkheads is actually the transom. So there’s a transom and four bulkheads, if you want to be technical. As a result, five compartments. We’ll probably only use two or three, and fill the others with closed-cell polyurethane foam. We’ll have to add some sort of ducting to get cables from one compartment to another, and we’ll need to make sure the ducting is sealed.

The main boat will be 2.4m long, and will have approximately 8 sealed compartments.