I first saw this boat on the front cover of a radio controlled boat magazine, and instantly I wanted one. The picture showed the boat speeding through the water with a big plume of spray coming off the back. Unfortunately at the time money was quite tight so I had to save over quite a few months to afford it, but finally I had enough and ordered one.
The first time around I never added the thin handrails round the back and along the sides, mainly as I didnít know how to do it. So with brass rod, solder and blowtorch in hand in barely an hour I had made railings to go round the back and sides. They were then sprayed white, and when dry stuck in place.
My next job was to transform the white ABS vac formed plastic cabin area into something more worthy of a power boat. For this I used some thin mahogany strips to make a new floor and areas where you would step. I also replace the tacky vac formed door into the lower cabin into a nice wooden one to match the decking.
Then onto the seats and sun deck area, which I had just the thing for. A while ago I started re-trimming my car in cream leather, so as I have several cow hides knocking around, I used a few off cuts to do the boat. The rear sun deck area and back seat where neatly covered, but the front seats were just painted cream as the leather was to thick to crease and fold around them. I then made new bases for the front seats and a new console where the steering wheel and dials would be using pictures of proper power boats as examples of what to do.
The first thing I done was remove the old red paint. I had originally painted two wide red strips down the side with a brush which was tacky to say the least as my painting skills back then left a lot to be desired.
So going for the upmarket sleek power boat look I always wanted, I chose bright red for the colour and went for flames at the front and flickering down the side. I also sprayed the large aerofoil over the cabin red, and brought the red down to the front in the form of two sharp lines. I also had to airbrush the windows in as my masking tape stuck and pulled some of the transfer off, but I think they look much better in black rather than the dirty grey sticker they were originally done in.
So with the paint taken care of, it was down to the cabin trim.
As with all things in life we wait for, when they finally arrive everything does not go as planned. I did build it and fit radio control gear to it, and took it down the boating pond, but it was then my illusions of this boat speeding through the water evaporated. The main reason was the twin speed controllers were graupners own units, but they were not very variable, and went from off to fast then faster still, then when you let off the throttle, the speed controller cut the power with a very abrupt reverse action causing the boat to shudder.
The other thing was the noise off the reduction cog gearing which could be heard from across the other side of the pond. So gone were my dreams of a sleek shiny boat speeding through the water, what I had was a rather a noisy barely controllable boat, that brought no pleasure to use whatsoever.
Then one day when my dad had took me down the boating pond the boat started having a mind of its own, and headed straight for the side at full power. I just managed to grab the front before it hit the side of the pond, but my dreams of a sleek power boat model were over. After that I didnít have the money or knowledge to put it right so it went in the loft, and thatís where it stayed for nearly 20 years.
As with everything in life you learn as you get older, and with more spare time on my hands, and more than enough knowledge to build it from scratch myself, out it came again for a refit.
I didnít think to take pictures before starting, as once I thought about it, I was a tad eager as normal and just got on with it. The following pictures show it as it is today, and the improvements I have made over the standard model
Everything was removed from the boat so I could start work. I shortened the prop shaft and made a housing to hold a bearing the motor end, then made a bracket out of carbon fibre to hold that and the motor in place. Going from two motors to one I thought I would loose a bit of power, but after a bit of research I found upping the pitch and size of the prop, plus losing as much weight as I could I could more than compensated for the loss of a motor.
I also decided to run the motor on 12v instead of 9.6, but this made it run hotter so as I had water cooling in and outlets fitted I decided to use them. My first test with just one coil and the two inlet and outlet pipes joined with tee pieces didnít work just having thru water forced through them by forward momentum. My solution to this was use two coils and shorten them both and feed each one through just one inlet and outlet. It seems adding a tee piece causes the water to not flow properly where with one on one it flows fine just through going forwards.
To keep things as light as possible I bought a micro servo for the steering, and removed anything that wasnít essential. This meant sticking receiver and speed controller to the hull, which in the case of the speed controller it aid cooling as it now sit against the constantly cold hull.
With the inside taken care of, I set about the rudder and prop.
I did away with the original props which were built into the rudders, and my first attempt at a rudder mounting plate, as it was a bit off and chunky and settled for a shaped mounting plate made form carbon fibre. Using thin ally sheet I made the shape to fit neatly under the back section then made it in carbon fibre. This is now very thin but stronger than both the other set-up thanks to the carbon fibre.
I also done away with my very heavy brass rudder and went for a super light weight carbon fibre tri-fin version. I came up with this rudder design as a conventional rudder only uses half the prop wash being passed over it when its turning, due to the other half misses the prop and continues going straight back. By adding a blade either side of the centre one, when turning the rudder now catches all the wash from the prop meaning it turns much mire responsively.
Next I swapped the standard graupner prop for a slightly larger diameter with more pitch and also added trim tabs to be able to control the angle the boat planes at better.
Now running on 12 volts with the single motor and much lighter than it was before, the boat actually goes quicker and handles more responsively than the twin motor set-up, plus you get a longer run time as well which was the main aim.