Raku 32

RAKU 32 PRICING FOR PLANS, KIT AND SUPPORT IS ANNOUNCED

 

We're offering a combination package of plans, comprehensive builder support and a foam/glass epoxy CNC Duflex kit from ATL Composites for USD69702. We think this is excellent value; but we're going to give early starters an incentive.

For the first three orders we will discount the package price by USD10702, making the total purchase price for the kit, plans and builder support USD59000. 

That discount can buy you a significant package of deck hardware or go towards the rig and sails.

The offer is subject to a 30 day quote for the kit from ATL Composites and is valid for the month of July 2018 only. 

 

 

Have any questions? We're going to set up a Q and A  page so your questions are welcomed as content to get it started. 

graingerdesigns@gmail.com

 

 

Raku 30 Mini Cruiser Catamaran

General Arrangement and Layout

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.

 

Saloon Space

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.

 

Closing Panels

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.

 

Navigation

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 and Wing Clearance

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.

 

 



Design Story. How the Raku 30 became the Raku 32

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.

 

Read the full story here.

 

 



Building Raku 32

We've chosen to work with ATL Composites and VDL Composites with the DuFlex kit build system. The construction method employs CNC cut PVC cored panels with glass/epoxy face laminates and a simple system of Z joins  for joining the panels. 

The kits save considerable building time and eliminate a lot of the laminating work that would otherwise be required.

Buy consistently using this system for all of the Raku cats we can develop an infrastructure where advice,  feedback and general information can be shared between builders.

Over time we expect that moulded components will be made available from various professional builders and this will further reduce the build time.

 

Can we purchase plans to build by another method?

The standard plan set and support infrastructure will be developed for building from the Duflex kit and other construction methods might require additional plans information. If you wish to build by another method please contact Grainger Designs to discuss.


SAIL PLAN RIG

LOA

Beam OA

Mast Length

Wing Clearance

Mainsail

J1 Headsail 

Code Zero

#1 Assymetric

#2 Assymetric 

Rig can be rotating or non rotating, aluminum or carbon.

 

The foredeck can have a conventional catwalk and forebeam or carbon longeron and forebeam.

9.8m/32'

5.16m/16'7"

13.537m

650mm/2'2"

38.08sq.m.

16.8sq.m.

35.3sq.m.

86.4sq.m.

 63.5sq.m.


Raku 30 steering and helm

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.

www.jefa.com/steering/steering.htm

 

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.



Tillers at the helm?

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.


What about the Rudders?

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.


Outboard Motor Installation

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.


The original Concept from January 2018

Builder Support

Materials Support will be provided by ATL Composites for builders world wide and VDL Composites for builders in Europe.

 

Build support will be provided by Grainger Designs by way of a Web Blog that will follow the build process similar to the blog for the R42 trimaran with added comments and tips.

R42 Build Gallery

 

Builders can also get support by contacting us direct by email. Emails are usually responded to within 24 hours. We guarantee a response within 48 hours.

It is our mission to provide our builders with comprehensive information on the build process and to get the materials quantities as accurate as possible to minimise wastage and avoid the need to reorder materials.

 

Until a number of boats have been built there will be a need to fine tune the materials list and provide additional building advice. We encourage builders to contact us with questions, problems they encounter, or suggestions  for improving the information we supply.

 

 


RAKU 32 Quick and Dirty Pricing Guide

We're going to be working with our partners to develop a realistic pricing guide for all of the products and services it takes to build a sail-away Raku 32.

 

For now here are some rough numbers to get the ball rolling. If you can help us to further precise these numbers (customers or suppliers) we are grateful to get your input.