Marine

Mini electric boat takes to the water for pint-sized motoring fun

Bay Area maker Josh Tulberg pushes off to motor along at up to 4 knots in his electric Mini Boat
Bay Area maker Josh Tulberg pushes off to motor along at up to 4 knots in his electric Mini Boat
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The Mini Boat can take two SLA deep cycle batteries, which are strapped in behind the seat
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The Mini Boat can take two SLA deep cycle batteries, which are strapped in behind the seat
To the right of the Mini Boat's plexiglass steering wheel is a dead-man's switch and throttle control, while on the left is a volt meter and power switch
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To the right of the Mini Boat's plexiglass steering wheel is a dead-man's switch and throttle control, while on the left is a volt meter and power switch
The Mini Boat's flat-bottomed hull is reported to offer excellent stability
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The Mini Boat's flat-bottomed hull is reported to offer excellent stability
The Mini Boat has a top speed of 4 knots
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The Mini Boat has a top speed of 4 knots
It looks like quite a tight fit, but the Mini Boat is designed to take a single occupant under 6 ft tall and weighing 100 lb or less
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It looks like quite a tight fit, but the Mini Boat is designed to take a single occupant under 6 ft tall and weighing 100 lb or less
Bay Area maker Josh Tulberg pushes off to motor along at up to 4 knots in his electric Mini Boat
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Bay Area maker Josh Tulberg pushes off to motor along at up to 4 knots in his electric Mini Boat
The Mini Boat is mainly constructed from marine grade plywood
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The Mini Boat is mainly constructed from marine grade plywood
Polyester rope runs from the steering column of the Mini Boat to a pulley at the rear, which is connected to the craft's electric trolling motor
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Polyester rope runs from the steering column of the Mini Boat to a pulley at the rear, which is connected to the craft's electric trolling motor
Carpeting on the floor and a thickly padded foam and vinyl seat offer single occupant comfort in the Mini Boat's teeny cockpit
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Carpeting on the floor and a thickly padded foam and vinyl seat offer single occupant comfort in the Mini Boat's teeny cockpit
Juice from the sealed lead acid battery is connected to the electric trolling motor via a cable running outside the Mini Boat's plywood shell
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Juice from the sealed lead acid battery is connected to the electric trolling motor via a cable running outside the Mini Boat's plywood shell
Polyester rope runs from the steering column of the Mini Boat to a pulley at the rear, which is connected to the craft's electric trolling motor
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Polyester rope runs from the steering column of the Mini Boat to a pulley at the rear, which is connected to the craft's electric trolling motor
Rapid Whale's Mini Boat is now available as a build-it-yourself kit
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Rapid Whale's Mini Boat is now available as a build-it-yourself kit

After seeing a few fine mini boat examples online, like the 8ft (2.4 m)-long Little Miss Sally by Paul Elkins, Bay Area maker Josh Tulberg of Rapid Whale decided to embark on a build of his own. But he wanted his Mini Boat to be shorter than the rest, so took to sketching, modeling in Solidworks and testing a 1:2.2 scale model in a hot tub before laser cutting and 3D-printing a petite electric single-seater and sploshing it in the water. Now the teeny electric boat is being made available as a build-it-yourself kit.

Tulberg's dinky little electric boat is 6 foot (1.8 m) long and weighs just over 100 lb (48 kg). It can be transported to the water in the back of a family car (with the back seats folded down) and the motor/battery installed at the river bank. It has a flat-bottomed hull for on-the-water stability and is constructed mainly from laser cut plywood, with some 3D-printed components and epoxy for waterproofing. Internal bulkheads keep it afloat even when the craft takes on water.

A rope-tie control system runs over a pulley at the rear and connects to the chunky plexiglass steering wheel to the front. To the right of the steering wheel is a dead-man's switch and 5 forward/3 reverse throttle control, and to the left a volt meter and a power switch. And there's a small amount of storage above the dash for stowing essentials. There's a handy safety light at the front for improved visibility, too.

A removable 12 V sealed lead acid battery provides the juice (though two can be strapped in if required), which is positioned behind the thickly-padded seat and cabled to the outboard trolling motor via a four-pronged connector. The Mini Boat can take a single occupant under 6'2" (188 cm) tall and weighing 200 lb (91 kg) or less, and is reported capable of motoring along at 3.5 knots (4 mph/6.4 km/h).

The Mini Boat's flat-bottomed hull is reported to offer excellent stability
The Mini Boat's flat-bottomed hull is reported to offer excellent stability

Rapid Whale is making a basic build kit available for US$950, which will include laser cut ply, 3D-printed components, steering wheel and shaft bearings, and various gaskets.

Home makers will need to add about $500 to $1,100 of off-the-shelf components before putting it all together and taking it to the local lake, canal or river though, including a Newport Vessels NV-Series electric motor, one or two deep cycle SLA batteries, double-braided polyester rope and a zinc-plated pulley for the steering mechanism, a foam and vinyl single seat, and chemical foam for the bulkheads. A full materials list and build instructions are available via the source link below.

It's an impressive, straightforward build and sure looks like fun, as you can see from the first launch video below.

Source: Rapid Whale

Mini Boat - First Launch

5 comments
PaleDale
That is cool :)
Buellrider
Make one bigger and you have something that other's might purchase.
ljaques
Wow, only $950 for 50# of plywood? Cool. Only add another $1,100 and week of your time to make it real? I hope they enjoy their windfall when the total sales number comes up to 8 units. LOL
MarcelH
It looks too tippy. One little wave from a passing bigger boat and you are swimming. Too small for the average American....by miles. For that kind of size it's better to use a sit-on-top kayak. I easily paddle 6 km/h in a sit-on-top. Maybe a good vehicle for amusement park's....for small adults and small kids. Sorry for negative feedback but I just don't see it taking off.
Riaanh
Very cool, but you do need a good sense of humour to appreciate it.