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03-06-2014, 04:50 PM
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#1
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Guru
City: Stuart FL
Vessel Name: Lucky Lucky
Vessel Model: Pacific Mariner 65
Join Date: Aug 2013
Posts: 2,760
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A Davit Question
We have an electric crane davit on our boat and will be lifting a 650# Boston Whaler to the boat deck. I am curious if anyone has ever had an electric crane "fail" mid-lift, and if so, how do you get the tender down? Input would be appreciated; please don't say cut the cable!
Thanks, Howie
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03-06-2014, 05:58 PM
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#2
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Guru
City: Longboat Key, FL
Vessel Name: Bucky
Vessel Model: Krogen Manatee 36 North Sea
Join Date: Oct 2009
Posts: 5,196
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Howie:
The answer is no and I've taken steps to avoid that possible incident. My davit crane is a custom build but the plan is to utilize the already mounted 900 lb. hand winch as the base point for one end of the line. From there, it goes out the boom of the davit, over one of two pulleys at the end and down to the load (snatch block) and back up to the boom, over the second pulley and down the boom to an electric hoist. That way if the hoist fails, I can simply lower the load by the hand winch at the other end of the line. All this, of course, has to be sized to the load you plan on lifting. If you don't trust a geared hand winch, there are heavy duty rack and pinion style hand winches that are slow to operate, but who cares if you only need to use it in an emergency.
Doing all this, I'll have less than 1300 bucks total in the building and assembly, 600 lb. working load rating with Amsteel 5400 lb. line.
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Larry
"When life gets hard, eat marshmallows”.
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03-06-2014, 06:09 PM
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#3
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Guru
City: Biloxi, MS
Vessel Name: Cajun Rose
Vessel Model: Biloxi Lugger
Join Date: Jul 2011
Posts: 1,384
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Howie, I've had the opposite problem a lot. I do a lot of 4 wheeling and I've had multiple electric winches' fail while pulling me out of the mud. I always have a come-a-long handy, back at the camp or sometimes on my 4 wheeler. I would think the same could apply to your davit. If it fails you could attach it to the davit and the cradle and winch buy hand your whaler and be on your way.
Paul
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03-07-2014, 08:04 AM
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#4
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Senior Member
City: Hampton Bays, N.Y.
Vessel Name: Grand Yankee
Vessel Model: 1981 49' Grand Banks Classic
Join Date: Oct 2007
Posts: 328
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Why not ask on the Grand Banks Owners site as to how many owners would or do carry a heavy Whaler on their Banks and what system is mounted on board to handle that weight.
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03-07-2014, 08:33 AM
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#5
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Guru
City: LI or Fla
Join Date: Jul 2013
Posts: 1,148
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Actually I think this is a great idea and cost effective:
Quote:
Originally Posted by swampu
Howie, I always have a come-a-long handy, back at the camp or sometimes on my 4 wheeler. I would think the same could apply to your davit. If it fails you could attach it to the davit and the cradle and winch buy hand your whaler and be on your way.
Paul
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03-07-2014, 09:09 AM
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#6
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Guru
City: North Carolina for now
Join Date: Aug 2011
Posts: 6,348
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Here is what people concerned about this use. I never got round to installing one; you have to have the winch as a maintenance item just like any other system on board. And, a back up alternative power source. There are variations of this, such as those you can open by inserting a fid on the end of a boat hook, rather than having line, I just couldn't quickly find an example. They must be designed to release under load.
Wichard Snap Shackle
OK , here is an example of one that uses a fid, Wichard makes all sorts of vaiations, so does Tylaska:
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George
"There's the Right Way, the Wrong Way, and what some guy says he's gotten away with"
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03-07-2014, 11:32 AM
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#7
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Guru
City: Powell River, BC
Vessel Name: Northern Spy
Vessel Model: Nordic Tug 26
Join Date: Feb 2012
Posts: 4,075
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A little chain hoist would work. Kito makes some nice small ones.
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03-07-2014, 02:45 PM
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#8
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Guru
City: Ft Pierce
Vessel Name: Sold
Vessel Model: Was an Albin/PSN 40
Join Date: Oct 2011
Posts: 28,148
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I thought just a knot or shackle to the boat bridle thrown over top of the davit or through a snatch block and then a couple round turns of the bitter end around something...that should be able to lower 1000-2000 pounds even by hand...can't get much simpler than that...
....raising it to the boat deck is a whole nother story....
I like chain falls over come-alongs to for up and down....
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03-07-2014, 02:52 PM
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#9
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Guru
City: Miami
Join Date: Jul 2013
Posts: 800
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Quote:
Originally Posted by hmason
We have an electric crane davit on our boat and will be lifting a 650# Boston Whaler to the boat deck. I am curious if anyone has ever had an electric crane "fail" mid-lift, and if so, how do you get the tender down? Input would be appreciated; please don't say cut the cable! Thanks, Howie
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On my current hydraulic Davit I had electronic controls which failed, but never a hose or a pump. I lowered the dinghy with a block and tackle then I figured a way to hot wire the controls in order to lift and stow it. Fwiw I cruised for four years with a 13' whaler and a 35 hp Johnson which made the package around 500 pounds. All we ever used to handle it were a pair of 5:1 blocks rigged bow and stern. Dink deployment and retrieval were usually a one man operation.
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03-07-2014, 04:13 PM
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#10
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Guru
City: Solomons Island Md
Vessel Name: Fryedaze
Vessel Model: MC 42 (Overseas Co) Monk 42
Join Date: Sep 2011
Posts: 1,721
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Our back up is to shift back to the old backup manual winch with a block and tackle.
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03-07-2014, 06:58 PM
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#11
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Guru
City: Biloxi, MS
Vessel Name: Cajun Rose
Vessel Model: Biloxi Lugger
Join Date: Jul 2011
Posts: 1,384
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Thanks MarlinMike. The come-a-long is galv. cable and very durable.
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