Get home propulsion - strange ideas
- Thread starter DDW
- Start date
The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.
If you have answers, please help by responding to the unanswered posts.
mcarthur
Senior Member
- Joined
- May 9, 2018
- Messages
- 297
- Location
- Australia
- Vessel Name
- Blu Emu
- Vessel Make
- Ligure 50' aluminium power catamaran
We have contacted OmegaSails about a get-home option. They are still selling their chute/kite. Upto 45 degrees either side of downwind, no need to active manage (but I would watch it!). The Lagoon 43 it was/is attached to is for sale at the moment.
I have a air-cooled 9hp Lister diesel that I was thinking about setting up to drive my shaft with a belt drive. Any reduction that matches the propeller would be possible, no gearbox but with 100 gals of fuel you could run it for 300 hrs.. Even if you could only get 3kts that's 900 miles of simple, reliable backup that's relatively cheap. According to my calculations it would push a 15000 lb boat with a 30 ft. waterline at 4.5kts. in calm water.
O C Diver
Guru
- Joined
- Dec 16, 2010
- Messages
- 12,878
- Location
- USA
- Vessel Name
- Slow Hand
- Vessel Make
- Cherubini Independence 45
I think a push boat is the answer.
The SkipJacks of Chesapeake Bay are sailing vessels (some over 100 years old) that drag dredges to harvest oysters. To compete with power boats, they are allowed to be pushed 3 or 4 days a week but must sail the rest of the time.
This is the Kathryn (over 100 years old).
Off her stern are a pair of davits to carry her push boat when not in use.
Her stern has a chock (between the ladder sides) that the bow of the push boat fits into.
This is her push boat. Its probably about 12' long and has a keel cooled, dry stacked Cummins 6BT 210 HP for propulsion.
When used, the bow of the push boat is set into the chock and either 2 steel poles or 2 sets of blocks and tackles link the stern corners of the push boat and the stern corners of the Skipjack. The rig is steered with the large rudder of the Skipjack. Shift and throttle cables are run to the Skipjack, so no one actually rides in the push boat. Thought you would find this interesting.
I like the concept of a diesel powered dinghy that could be side tied near the stern. Fortunately my cruising doesn't require this level of redundancy, but it's fun to consider the possibilities.
Ted
The SkipJacks of Chesapeake Bay are sailing vessels (some over 100 years old) that drag dredges to harvest oysters. To compete with power boats, they are allowed to be pushed 3 or 4 days a week but must sail the rest of the time.
This is the Kathryn (over 100 years old).
Off her stern are a pair of davits to carry her push boat when not in use.
Her stern has a chock (between the ladder sides) that the bow of the push boat fits into.
This is her push boat. Its probably about 12' long and has a keel cooled, dry stacked Cummins 6BT 210 HP for propulsion.
When used, the bow of the push boat is set into the chock and either 2 steel poles or 2 sets of blocks and tackles link the stern corners of the push boat and the stern corners of the Skipjack. The rig is steered with the large rudder of the Skipjack. Shift and throttle cables are run to the Skipjack, so no one actually rides in the push boat. Thought you would find this interesting.
I like the concept of a diesel powered dinghy that could be side tied near the stern. Fortunately my cruising doesn't require this level of redundancy, but it's fun to consider the possibilities.
Ted
jimisbell
Guru
- Joined
- Jan 13, 2018
- Messages
- 643
- Location
- USA
- Vessel Name
- Papillon
- Vessel Make
- 1978 Mainship 34 Trawler #95
Didnt want to join the fray because I started a similar thread and was trashed by people who thought I was an idiot for even suggesting it. Where I cruise, up to 100 miles offshore, the water is warm (probably couldnr keep a "bubbler" cool when the water is 90F, the bottom is only 100' down, and the winds are toward the land. If the wind is foul, you can drop an anchor and wait. With onshore wind, rig a sail (got much derision for that idea). People kept saying what if the wind isnt in the right direction and they did not understand "wait" A sailor knows how to wait for the wind.
I also suggested a 10hp electric motor run of the genset (Mine is a 8kw) belted to the drive shaft. People said, "but thats slow." Sure is, but if its all you got, its faster than walking. They also said, it will ruin the tranny. I responded, "I dont care if I dont die of thirst in the ocean". There are more naysayers than you can shake a stick at that dont understand not wanting to die at sea because you are not inventive.
0 knot into the wind is better than 3 knots backwards because you have a dead engine.
I also suggested a 10hp electric motor run of the genset (Mine is a 8kw) belted to the drive shaft. People said, "but thats slow." Sure is, but if its all you got, its faster than walking. They also said, it will ruin the tranny. I responded, "I dont care if I dont die of thirst in the ocean". There are more naysayers than you can shake a stick at that dont understand not wanting to die at sea because you are not inventive.
0 knot into the wind is better than 3 knots backwards because you have a dead engine.
cardude01
Guru
- Joined
- Nov 26, 2012
- Messages
- 5,290
- Location
- USA
- Vessel Name
- Bijou
- Vessel Make
- 2008 Island Packet PY/SP
That’s really interesting. Thanks for those pics and explanation.
This guy did just that.
http://janice142.com/Articles/ManateeMoves.html
Last edited:
Having a secondary aux motor (of course smaller) may be a easier permanent fix running a separate smaller propeller like this.... but it would only work on a larger boat. The normal size prop. may be too big to turn but the small motor on it's own.
They should probably have a feathering prop on that wing engine.
Wing engines are fine in a large boat. Won't fit in mine. There is a dilemma in a certain size range, around 30 - 38 ft or so. Too small for a wing engine, but big enough to go places where TowUS doesn't operate. This is the sweet spot for a solution that uses the diesel onboard to make slow progress towards civilization. It seems logical to use the diesel energy converter I already have installed and maintain (the genset) to supply this if possible.
Wing engines are fine in a large boat. Won't fit in mine. There is a dilemma in a certain size range, around 30 - 38 ft or so. Too small for a wing engine, but big enough to go places where TowUS doesn't operate. This is the sweet spot for a solution that uses the diesel onboard to make slow progress towards civilization. It seems logical to use the diesel energy converter I already have installed and maintain (the genset) to supply this if possible.
markpierce
Master and Commander
- Joined
- Sep 25, 2010
- Messages
- 12,557
- Location
- USA
- Vessel Name
- Carquinez Coot
- Vessel Make
- penultimate Seahorse Marine Coot hull #6
Agree about the feathering prop.
Ok see where you are coming from, so how about a, Yanmar D27 Diesel outboard engine or similar? An outboard but runs on diesel, hooked on the back and just run a temporary hose back to your diesel tank ( with it's own inline filter).
Small enough to be stowed off season and could tilt up till required.
Allan
Last edited:
BruceK
Moderator Emeritus
- Joined
- Oct 31, 2011
- Messages
- 13,347
- Vessel Name
- Sojourn
- Vessel Make
- Integrity 386
Memory says Marty`s Bay Pelican KK has a wing engine with separate shaft drive, regularly exercised for docking etc, giving the handling plus of twins and economy of a single. Ideal set up imo,but anything that gives some back up is good for a single.
We have a lot of Clipper 40s here,rare with twins, most with singles, yet to see a wing engine in one but it would make a lot of sense.
We have a lot of Clipper 40s here,rare with twins, most with singles, yet to see a wing engine in one but it would make a lot of sense.
Something like that but smaller would be ideal. If you can find one of those, it's around 200 lbs +, and way more power than is necessary.
I have a sailboat. But the powerboat is in the PNW where there is no wind an no towing service. You are in SF Bay where there is nearly always wind - though it is nearly always from the same direction. How's the tacking angle on that Duck?Get a sailboat but motor as long as the engine works. Subscribe to a towing service if available.Not a sailboat:
It appear that it should not be just thrust but also velocity what needs to be correlated to the motor's horsepower. For very low speeds, I am sure that a slow velocity will result in a higher thrust.
Now to the question: the idea of an electric out drive interfaced to a 120VAC generator is not new as there is a very simple and inexpensive configuration that would match two 60 V DC out drive motors to an 120 VAC generator.
It is a good idea that I have investigated. In fact, there are DC and AC motors that work at 120 volts AC or DC that may be retro-fitted into the out drives. Two "get-home" out drives would allow the vessel to be electrically steered with them.
08-08-2018, 02:33 AM
Now to the question: the idea of an electric out drive interfaced to a 120VAC generator is not new as there is a very simple and inexpensive configuration that would match two 60 V DC out drive motors to an 120 VAC generator.
It is a good idea that I have investigated. In fact, there are DC and AC motors that work at 120 volts AC or DC that may be retro-fitted into the out drives. Two "get-home" out drives would allow the vessel to be electrically steered with them.
balder8
Senior Member
- Joined
- Aug 15, 2018
- Messages
- 107
- Location
- France
- Vessel Name
- BALDER VIII
- Vessel Make
- North Sea Trawler 57' OC
Hello,
It is always a great pleasure to read comments and post on this forum.Here in Europe, we are more focused on fast planning motorboats or sailboats!
I have a KEY POWER get home drive fitted on my North Sea Trawler 57' OC and I am happy with it. Of course, I should be more happy with a second option like kite or bipode mast to be raised with some genoa or furling main sail.( we call that in french, " ceinture et bretelles!")
Kites are becoming more and more popular here. The question is: how launch it and recover it when in rough seas, offshore. A small german company is developping a system fitted on fore deck with an interface like autopilot. Maximum size is more or less 17 metres carres, not enough to move my 60 metric tons steel trawler! I do not know if the french owner of Lagoon 43 was happy with the omegasails, I tried to contact him but had no response.The sky sail system for cargo ships is another story and the cost prohibitive for leasure yachts under 60 feet.
I expected to use my passive stabilization rig ( I have KEY POWER STABS aboard) but I do not know if two small sails on starboard and portside should be usefull.( like on TEKA III pictured page 46 fourth edition of "Voyaging under power" by Captain Robert P.Beebe)
Aboard MY BALDER VIII
MMSI 227 399 280
call sign FAD4970
Currently underway GIBRALTAR
It is always a great pleasure to read comments and post on this forum.Here in Europe, we are more focused on fast planning motorboats or sailboats!
I have a KEY POWER get home drive fitted on my North Sea Trawler 57' OC and I am happy with it. Of course, I should be more happy with a second option like kite or bipode mast to be raised with some genoa or furling main sail.( we call that in french, " ceinture et bretelles!")
Kites are becoming more and more popular here. The question is: how launch it and recover it when in rough seas, offshore. A small german company is developping a system fitted on fore deck with an interface like autopilot. Maximum size is more or less 17 metres carres, not enough to move my 60 metric tons steel trawler! I do not know if the french owner of Lagoon 43 was happy with the omegasails, I tried to contact him but had no response.The sky sail system for cargo ships is another story and the cost prohibitive for leasure yachts under 60 feet.
I expected to use my passive stabilization rig ( I have KEY POWER STABS aboard) but I do not know if two small sails on starboard and portside should be usefull.( like on TEKA III pictured page 46 fourth edition of "Voyaging under power" by Captain Robert P.Beebe)
Aboard MY BALDER VIII
MMSI 227 399 280
call sign FAD4970
Currently underway GIBRALTAR
Airstream345
Guru
- Joined
- Jul 3, 2017
- Messages
- 1,015
- Location
- United States
- Vessel Name
- FORTITUDE
- Vessel Make
- Kadey Krogen 54-8
I vaguely remember a KK42 I toured had a hydraulic driven chain drive powered off a generator PTO. Seems like a pretty cool solution (assuming the prop/shaft are functional).
Sealife
Guru
This was the set up I had. Issue was the 12kw genset was way oversized for genset duty. Originally sized for engine hp, not gen head. Also had issues with heat build up. It workd but according to previous owner not very well.
Side note the BW gearbox was able to freewheel w/o damage in this set up.
Side note the BW gearbox was able to freewheel w/o damage in this set up.
dochip
Member
Get home
We have (and love) a Torqeedo electric outboard for our Portland Pudgy dinghy, and we carry two batteries for the Torqeedo. In the scenario described, if we lost our single Cummins, we'd use the Pudgy as a tug to move our trawler, and use our diesel generator to recharge the battery that was not in use. Voila!
We have (and love) a Torqeedo electric outboard for our Portland Pudgy dinghy, and we carry two batteries for the Torqeedo. In the scenario described, if we lost our single Cummins, we'd use the Pudgy as a tug to move our trawler, and use our diesel generator to recharge the battery that was not in use. Voila!
I would dearly like to know how fast the Tq on the Pudge will push your AT34, since that's what I want to push. Please do that experiment and report back!!
Not sure of the specifics, but I think you can discharge the in-use battery on the Tq much faster than you can recharge the spare from the genset, with typical equipment anyway. So you'd go a little, then rest a little. Which is better than not going. Wires (and suitable converters) from the genset to the Tq would allow continuous use.
TowLou
Senior Member
I never looked how did he fare? Them motors moved weight but then again in 8 hours would drain a 36v battery weighing over 1500 pounds plus the hydro pump motor running so im on the fence for my opinion on it. Even tho those motors were maybe 150 or so pounds. But I guess would run if you had a genny wired right.
