How The Unique Shearwater Sleek & Stylish Speedboat Was Designed And Developed

The creator, James Oakley, tells his own story:

I have been boating most of my life and always wanted to build my own craft. The majority of my career has been spent developing ‘things’ of one sort or another and particularly small gas turbines for renewable power generation from waste gasses. This has exposed me to all sorts of skills and materials, and I have always been attracted to the use of aluminium, which is not only recyclable but is great to work with and form different shapes, while being lightweight, durable, and long lasting as well as maintenance free. A lot of the Superyachts are built from Aluminium.

For a long time I have harboured the desire to the possibility of building a small speedboat around 6 metres / 20 foot in length and of a classic design. But before I could start, I realised the best method of construction would be MIG welding as opposed to riveting. It is quicker and forms a continuous joint if required and is well suited to building this type of boat. I undertook some MIG welding during my apprenticeship at Rolls Royce though that was a long time ago!
I bought myself a new MIG welding set and then decided to research building a small-scale boat to start with, to fine tune my skills again.  I then bought the plans of a small 2.5 metre / 8 foot all aluminium dinghy and had a local laser cutting company cut out all the aluminium profiles for me. I then fabricated this dinghy over a period of a few weeks in my spare time and was really pleased with the result. I also became friendly with a professional boat builder in Newhaven and he showed me a lot of the techniques involved with building boats and using aluminium.

So now it was time to get serious!  I did a lot of research into the different types and styles of speed boat around the right length. I then arrived at the style I liked which was similar to the Riva, Chris Craft and Albatross boats built in the 1960s.
The next task was to find a marine architect who could design the boat so it could be built in aluminium and an all welded construction, as well as complying with all the regulations. (RCD Compliance and CE certification). Eventually, I found Hal Whiteacre in America, who designs yachts and power craft, including boats for the Great Lakes where the wind can blow up to become quite choppy. This seemed the ideal solution, so we reached an agreement for him to design the Shearwater 19 classic style speedboat (or runabout as it is known in America!)

Over a period of months, the design took shape and Hal produced a set of working drawings as well as all the CAD files that enables the aluminium panels to be cut out on a laser cutting machine. All the panels, hull plates, frames and bulkheads are cut out of flat sheet and numbered which shows their location to one another. Unlike fibreglass which requires an expensive mould, building in aluminium is self-jigging and therefore much easier and cost effective to make a one off. In order to build the speedboat I would need a steel cradle for the boat to sit on so this was also designed and fabricated by myself.

I began the Shearwater speedboat by welding the two bottom hull plates together, which sat on the build cradle and then working from bow to stern I tack welded the eight bulkhead and frame sections into position along with the stringers. Then the side panels and transom were fitted and these were just initially tacked in place to allow things to be realigned later if need be. Once this was complete the two deck sections (there is a join in the centre running across the deck) were also tacked into place, the entire boat being assembled the right way up. Most of the time this was undertaken on my own, occasionally helped by my wife Annie, holding pieces in position while I tack welded them.

After very many hours of welding over a period of months the hull was virtually complete and I purchased a new Mercury Marine engine that was then adapted with a suitable gearbox for an inboard drive particular to this boat, along with a prop shaft, 5 bladed propeller and stainless steel rudder designed specifically for this application. I then thought that the rest of the work, fitting out the boat would be quite quick and straight forward, but how wrong I was! This seemed to go on forever as it involved making lots of brackets for the seating, interior panels, fuel tank, steering and everything else that had to be fitted. I also had to design and make the windscreen, so I did this by starting with several cardboard templates until I got to a form that looked right. This was then copied to make a robust wooden template/former. I found a company in Norfolk who then hot moulded an Acrylic screen into shape using the former that I had made. It was then a question of making nice polished stainless steel brackets, centre support and a bespoke rear view mirror to finish it off.

Once I had installed the hydraulic steering system, fuel system, exhaust system and the basic electrics it was then time to get it on the water and try everything out before the interior was properly fitted out. I found a local lake that was normally used for sailing and they kindly gave me special permission to launch and test her out. This was an exciting day and the first time out she ran very well, and it was great to see her on the water powering along nicely. There were some adjustments and small items that needed resolving so this was completed and then another venture onto the lake proved that all was very well.

For the speed boat to be legal she had to be built to comply with the Recreational Craft Directive (RCD), she can then be given a unique hull number and CE marked. In order to do this, I decided to use the services of a third party that specialises in such things as there is a lot of testing and measuring to be undertaken. Many matters such as stability and buoyancy at full load, the ability to turn within a certain distance, noise level readings and many more aspects need to be proven. I was very pleased to pass all the tests including the exhaust noise test by just one decibel! So now the boat was compliant it was time to move on and finish off. Yet again I thought this would be easy but was wrong!

Preparing all the interior panels seemed to take forever to make as I had to first produce my own patterns and backing panels and weld in brackets to suit. These panels could then be professionally upholstered along with the seating. I was also incredibly lucky in meeting a semi-retired boat painter who had huge experience and was able to produce a first-class finish in a Gucci style colour scheme. Alongside this I was introduced to a variety of boatbuilders in Southampton who were able to make the mahogany rubbing strip and dashboard and advise on other finishing items. All of this took many months to complete.

Once the Shearwater 19 was finally finished she was taken to a lake in Chichester where, with special dispensation some maximum speed runs and drone photography were undertaken. She looked fantastic!  When starting up and leaving the jetty the exhaust has a lovely burbling sound as it comes out just above the waterline, so you get that special feeling of its effortless and smooth power.
It was very exhilarating to see her finally finished and performing as she should after all those years of work, and a real thrill to drive as she handles very smoothly and gives you a great buzz and feeling of something special as you skim over the water.

James now needs to move onto other projects and so this superb boat is for sale. Please see www.seacottmarine.com or call him on +44 (0)7860 711595.