Preview: An Electrifiying Twist To The Gunning Dory: G.E.M.A. – The Gentleman’s Electric Mess-About

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G.E.M.A, otherwise known as the Gentleman’s Electric Mess-About, has an electrifying new twist on the classic Chamberlain/John Gardner Gunning Dory.  She was designed and built by Eric Jacobssen, Owner and Master Builder at North Brooklin Boats, in 2014.  She is propelled by oar and an Aquamot A20 electric motor.

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12 Responses So Far to “An Electrifiying Twist To The Gunning Dory: G.E.M.A. – The Gentleman’s Electric Mess-About

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    Jon Arcuni says:

    When I looked at this boat I said to myself “WOW”. I was a member of the Manhasset Bay Sportsmans Club in Manhasset Bay Long Island N.Y. and we had fishing competitions with other sportsmen’s clubs on the North Shore of Long Island. There were six clubs. competing. This was in the sixties. It probably still goes on today.

    Almost all of our fishing was done at night, and mostly by trolling sand worms at a slow rate around and among the rocks on the points. At night the begalls would not eat the worms, it was either striped bass or big eels. Although we had many fine fishermen in our club, we were constantly getting beat by other clubs where the members had “sneak boats”.

    There was no member in our club that had a “sneak boat”. We were at a disadvantage.

    A “sneak boat” was narrow, made of wood, approximately 16 ft long and powered by a single cylinder, “make and break” Arcadia gas engine with a big flywheel. It was steered by foot petals, leaving the hands free for landing striped bass fish. A “sneak” boat could troll at 1/2 a knot, just enough to keep the worm off the bottom, and if you hit a rock, it would just bounce off.

    At that time these boats were being handed down from father to son and there were no Arcadia “make and break” engines available. I fished with a 18ft Thunderbird, 110 HP Evenrude, and a 6HP 2 cyl Evenrude on a transom mount with separate controls. Steering was done with a post through the gunwale and pulleys on the starboard side. It never seemed to go slow enough or be quiet enough. I did catch a lot of fish however. Never the winner.

    Now, when I see this electric boat, I can think of nothing better for fishing striped bass at night.

    If I still lived back on Long Island, I would make one tomorrow. There is nothing like fishing at night for striped bass around the points, dragging sand worms. I really miss the night fishing.

    It is a whole different ball game fishing the Hanibal Bank in the Pacific off of Panama. No sense of serenity like night fishing in Long Island Sound.

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    John Sims says:

    Beautiful boat! GREAT idea!

    I’m hoping that you can put me in touch with someone who can give me very in-depth technical information on GEMA.
    Thank you!

    • Steve Stone

      Steve Stone says:

      Hi John. The link to North Brooklin Boatyard and Eric Jacobssen is above in the Nav Further section.

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    Rich Dirks says:

    Having completed the construction of a 15′ Joel White designed cat boat with a beautiful Mahogany transom, I just couldn’t bear putting an outboard on it so I began the journey of adapting an 80lb thrust Minnkota electric trolling motor as aux power.

    I started by stripping the motor down to just its carbon fiber shaft and the pod. An 80lb thrust motor is designed to work on up to a 25′ bass boat. The Marsh Cat weighs just shy of 1250 lbs. With 4 people it easily pushes it at 3-4 knots with the standard 2 blade prop.

    I fabricated a motor mount using black delron like plastic and attached it to the transom using 3 Ronstan 1/4″ pintels & gudgeons. The shaft was cut such that there is just enough length to allow the pod to be in the water far enough to get a good “bite” but the pod can be raised up and turned parallel to the transom so as to eliminate and drag through the water. Total length of pod & shaft is about 36″ but only 18″ rises above the transom.

    When the shaft was taken off the standard head it left an opening in the top of the shaft where the two motor wires came out. The top had to be sealed so that no water could enter the inside of the shaft and get down to the inside of the electric motor. After considerable searching, a solid polyethylene shovel handle was purchased, cut down to a small stub and placed over the top of the shaft. This serves as both a watertight seal and a nob for raising the motor up and out of the water.

    The 24v motor is powered by 2 group 27 batteries, each mounted under the seats about mid-ship so that they balance each other out. The PWM motor controller was purchased from Minnkota and provides for variable speed in both forward and reverse.

    After using it for one season last year I’m very satisfied with the results. It is very similar to the way the motor is incorporated into the GEMA described above. I’ve probably got about $1,000 into the parts but a whole lot of sweat equity in designing and fabricating it as I went along. Would I do it again? Probably.
    Rich Dirks, Egg Harbor, WI

    • Avatar

      Guy Pepin says:

      Very curious to know how long you can run this motor on those batteries. Naturally it will depend on speed, and how low you are willing to drain the batteries before re-charging. Any data you can provide will be appreciated.

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    Larry Cheek says:

    Just for the record, here’s my experience with electric boating:

    When I built my Devlin Winter Wren (19′ gaff-rigged sloop, 1900 lb.) I decided on electric auxiliary power for a variety of reasons: environmentally friendly, quiet, lightweight and easily removable outboard motor. I bought Torqeedo’s first-generation 801 motor, which they advertised as equivalent to a 2HP gasoline outboard.

    The Torqeedo had adequate power; it would propel my boat at 4.4 kt in still air at about an 80% throttle setting. However, when I launched the boat in 2011 I didn’t yet understand the reality of Puget Sound cruising: extremely fickle summer wind, where if the day’s destination is 20 nm distant, you’d better be prepared to motor half to three-fourths of the distance. With an estimated practical range of about 12 nm with two 105 AH AGMN batteries, I was mostly limited to daysailing.

    Worse, the Torqeedo proved to be grossly unreliable. It repeatedly stranded me in 0 wind situations a mile or more from my home marina. It had to be repaired three times under factory warranty. Torqeedo refused my request for a full or partial refund.

    After about the sixth stranding and third repair I donated it to a charity rummage sale and bought a new Tohatsu 4HP gas outboard.

    Now in its third season, the Tohatsu has proven to be 100% reliable. A three-gallon tank gives me a range of 40 nm. It’s heavy and noisy, but it does its job perfectly.

    The cost differential is also significant. The electric outboard, two batteries, charger and wiring totaled about $1900. The gas outboard and auxiliary tank came to about $1200.

    I’ve had no other experience with marine electric propulsion, and I hope this G.E.M.A. enjoys long and excellent service from its Aquamot. The concept of electric power remains alluring. But it’s still awfully expensive, and I found it didn’t work for me.

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    Jeffrey Kopczynski says:

    Wonderful ! Having recently acquired a Torqeedo electric outboard for our Porta- Bote, we appreciate a good G E M A. Carry on ! Jeffrey A. Kopczynski

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    David Brannon says:

    I love the concept. My question is about how long to do batteries last for this type of motor?

    • Avatar

      Maine Classic Boats says:

      Hi David,

      At a little under half throttle, say 2 – 3 knots she will go for 6 – 8 hours. At full throttle, a touch under 6 knots, she will go for about 1 hour. These estimates are from full charge to 20% of charge which you really do not want to get below very often. There are batteries with more capacity both AGM’s that are a little larger and heavier and Lithium Ion which are lighter, smaller but considerably more expensive.

      Eric Jacobssen

  • Avatar

    Steven Wallace says:

    Beautiful, so sweet. Is this boat S.C.R. controlled ?

    • Avatar

      Maine Classic Boats says:

      Hi Steven,

      The charger on this boat is a NOCO Genius charger. I do not believe they are SCR. That said, my knowledge of the SCR Thyristor technology is limited to knowing it exists and has advantages and disadvantages in specific circumstances. If you would like to educate me, and others, please do so.

      Eric Jacobssen


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