Accommodation in the hulls
The spaces in the hulls have had a pretty serious workout in terms of design optimisation. The real sticking point in the design process was access to the hulls and we headed down a lot of different rabbit holes in search of a solution that provided good access without compromising the helm position or the cockpit seating.
Access to Hulls
The first iteration of the design didn't have the companionway access to the cockpit, just the passageway amidships. However this was not ideal because you have to stoop as you go down or come up. IT's a small noat and you have to accept some compromises but this was one I was keen to avoid if possible. e decided to I think it was Dan who came up with the solution we have here now which I'm pretty with.
The companionway opening is offset from the steps and we're still looking at ways to improve this. We can move the opening outboard a little and we can make the top step quite wide.
In the port hull the bottom bunk serves as the bottom step and the top step is partially over the berth. We've sketched up a couple of ideas for folding or sliding the step out of the way if someone is using the berth.
The folding idea works well because if blocks the access from the cockpit if someone is sleeping in the berth.
If someone in the cockpit want to use the head they have the alternative access through the saloon and down the steps amidships. We've kept that access pretty wide so as not to make too much of a closed in feeling down in the hull.
The saloon space offers more flexibility in terms of layout.
The fore and aft seats are a fairly obvious choice as they can also serve as berths if you have a team on board. The area forward of the mast post can accommodate beds which may or may not fold into a sofa/lounge arrangement, and a lightweight table could be moved between the cockpit and the sheltered cabin as the need arises.
We expect the boat will be used in "open cabin mode" most of the time and the door panels are designed so you can lock up the boat when you're not on board. There is a total of four closing panels and they can be stored quite easily under the seats. The panels can be made from foam/glass and I expect we will find a simple solution for locking them into place.
I considered putting a nav stn on the port hull but when you look at how much space there is in the wing deck saloon there didn't seem much point in going below to navigate. A light plastic stool and the mobile table previously mentioned would serve the purpose well. The table could be custom made with a large drawer under for charts and nav equipment.
The inboard side of the port hull is ideal for canvas or netting stowage bags, or a shelf for kitbags.
Headroom at the entrance to the saloon cabin is 1600mm or 5'3"
In the hulls the headroom is 1843mm which is six feet and five eights of an inch.
Wing clearance is 660mm (2'2" a the entrance to the cabin. That's pretty generous for a boat this size and that's measured at the fully loaded displacement on the DWL.
Sometimes the solutions you find to design problems are really obvious once you've solved them. That was pretty much the case with the companionway entries to the hulls on the Raku 32.
It took quite a bit of reworking to get to the solution and in the process we weren't thinking of another issue that ultimately resulted in a change to the length overall.
Rig can be rotating or non rotating, aluminum or carbon.
The foredeck can have a conventional catwalk and forebeam or carbon longeron and forebeam.
We would like the Raku 32 to steer more like a sports car than a bus. There's probably some pretty damn good engineering in bus steering systems these days but I think you understand where we want to go.
We designed the linkage system to be as direct, as friction free, and as simple as possible.
Two idler shafts, four tiller levers (not including the rudder fittings) two adjustable drag links and a single link bar that we tucked up inside the aft beam because we want Raku 32 to look as cool from behind as she does from other view points.
The whole assembly can be built up from standard components you can find on Jefa's web pages. Jefa even have the pricing on line.
Go to their steering systems web site, not the rudder web site.
Not sure which components to select? Fear not, we'll be working with Jefa's design team to specify the complete steering kit and we'll provide a drawing with the all the parts specified as part of the plans set.
It looks as though they might be blocking access and taking up valuable seating space when you're not under sail? Yes, that would be an issue but we've thought about that and there are two options.
One is to have the tiller swing up so you can park them in the vertical position while you're not sailing.
The other is to be able to pin the tiller fore and aft and then release it so it can rest athwartships while not being used. We will have that sorted before have the rig up.
Rather than reinvent the wheel (the rudder in this case) we would like to find an existing rudder and case that could be incorporated in the kit or as an additional module to the kit, even if some modification is required.
It could be a kick up system or a dagger style system as shown in the renderings.
We do have existing drawings for both systems for our trimarans but we would prefer to use something of the shelf is we can find something suitable. More to come on this.
Can the rudders have T foils? Yes, no reason why not as long as the system is adequately engineered for the loads.
The motors mount under the aft beam protected from waves by the chamfer panel which provides a fairing for the mounting block and stern bracket.
The drawing here shows the geometry for a Suzuki DT9.9/DT15 long shaft.
If the boat is light and the transom is clear of the water it may be necessary to lower the height of the mounting block. Most outboards tilt between 70˚ and 75˚. In this drawing the motor is tilted 71˚ leaving the lowest point of the motor 426mm above the water.
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