Hi Shipmates,

The Polycarbonate Hull
the only part I will use.

The rest will be scraped
(Equipped with Twin 380 Motors Vector-push design for easy control
Radio Controller with antenna Wall Battery Charger 7.2v NiCD 1800 mAh NiCD Rechargeable battery Extra Pair of Propellers English Manual
Length: 32 Inches Battery Type: 7.2V 1800 mAh Transmitter: 3 Channel Motor Type: Twin 380 Charger: Supplied
Skill Level: Beginner / All Levels Speed: 20 - 25 mph+ Battery Requirements: Vehicle: 7.2V 1800 mAh NiCd Rechargeable Battery (Included) Transmitter😊

I have stripped out all hardware, filled holes in the transom and affixed polystyrene to the hatch / cabin to make it buoyant, so it will not sink if it falls in the water.

Regards
Roy

Hi shipmates,

The Hull is a well designed double stepped hull made of Polycarbonate (The same stuff they made crash helmets from).

Have reinforced the transom with some epoxy resin.
Added insulating foam for pipes into the rounded part of the hull.
Added some hardware to the transom.

Motors are on order, gave myself a choice of two
A 3670 1900kv or a 4074 1550kv the latter may be better in theory.

Regards Roy

Hi Shipmates,
After a few too many bad experiences with expanding foam I though of a less dangerous way to stop my boat sinking (experimental).

Basically it is polystyrene balls and acrylic paint (white) mixed together so the balls are covered and stick together (patient pending) joke.

Thus will follow the rough shape of the hull, but will take some time to dry.

Regards Roy

Hi Shipmates,

Received the motor today!
It is a 4074 at 1550kv with water cooling jacket, picture to compare to a 3660 at 3800kv.

Regards Roy

Hi Shipmates,

RECAP
After a few too many bad experiences with expanding foam I though of a less dangerous way to stop my boat sinking (experimental).

Basically it is polystyrene balls and acrylic paint (white) mixed together so the balls are covered and stick together (patient pending) joke.

Thus will follow the rough shape of the hull, but will take some time to dry.

UPDATE
Unfortunately after a few days the stuff was only dry on the exposed surface.
So I had to remove it all by hand and wash out the interior of the boat before refilling with dry polystyrene balls and fitting a solid polystyrene bulkhead, which appears to have worked ok.

Regards Roy

Hi shipmates,

Today I received my stinger by post, after a lot of cutting and filing I got it to fit and made it adjustable up 1 degree and down 2 degrees.

I have cut down the rudder as a bit too deep.

I've fitted the motor and had a bit of luck with that by changing the mount to a narrower based one I am able to fit it snuggly between two of the spray rails.

I have just epoxied the bent shaft into position.

Regards Roy

Hi Shipmates,

I add some epoxy resin under the motor after making some small dams to keep it in place.

Add a small strengthing bar across the front and rear of the motor

Added a battery rack to port stern, to counter prop torque, and keep the COG towards the stern.

Motor specs.
no load 1.8A
Max voltage 38v
Max current 73A
Max power 2800w

but will only run on 4s

Regards Roy

Hi Shipmates,

Added water cooling, servo and water outlets. a bit of soldering for the ESC (125A 6S ) setup a Radio and receiver and a test in the test tank No1 (the bath).

Test
Fail No1, Forgot to do up grub screw on the dog drive so prop moved up the shaft a bit, easy fix.

Fail No2, I've had this before on boats with a low level prop-shaft that is below the water line, yes water slowly ingresses up the shaft, especially when not in motion.

Cures,
a) Add grease between outer metal tube and the liner as there is a small gap between them.
b) Grease the flexi-shaft, but normally a thin oil is used.
c) The most invasive is to build a grease box around the shaft end in the boat, and fill it with grease as last resort.

Regards
Roy

Hi Shipmates,

Re Hi Roy, it seems like a very valuable electrical setup, especially the motor and the ESC (they are very expensive I imagine).
The brushless motor has remarkable performance.
Can you attach some photos of the propeller area and the point where the water enters?

The motor cost £56 including water jacket, the ESC has been modified by myself to add water cooling it is a dual direction 125A cost £31.

I only oiled the shaft but I need to disassemble and add a heavier grease to parts of the assembly, to prevent water ingress.

Please note that there is meant to be a gap between the prop and the end of the stinger of about 1mm, this is to allow for shrinkage of the flexi-shaft when under load.

Regards Roy

Hi Shipmates,

After second trial run, still leaks. so have added a grease bucket (not shown). but see above post.
Also I found it was turning too quick, no control, I guessed this was lack of turn fins, so have fitted a couple of carbon fibre and red anodised fins. see pics
Have not tested them out, that will be on my next visit!

Regards Roy