Trailer Modifications for Launching/Retrieval

Discussion in 'Sailboats' started by Paul Calder, Jul 6, 2019.

  1. Paul Calder
    Joined: Jul 2019
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    Location: Maine

    Paul Calder New Member

    I hope this is the right place for this post, it's my first on here.

    I have a 27' full keeled but centerboarding sailboat weighing in at about 5 tons and draft 3'. I'm hoping for some opinions on a launching and retrieval setup for the trailer/boat combination.

    I've acquired a hefty home-built trailer that I intend to modify for the boat. On lighter boats I've used tongue extenders and I don't see a reason why I couldn't add one to this trailer as long as it was strong enough but I've never loved that setup with keelboats. With 3' draft I would prefer to use a winch and cable system. I think I have a good design but I'm surprised by how uncommon it is for people to launch boats this size directly from a ramp and I've never seen exactly the setup I would like to build which is not always a good sign!

    My solution would be a simple removable wheel for the tongue of the trailer and a 12v winch. You pull up on the ramp, line everything up straight, roll the trailer in on the cable and winch the boat back out. The wheel would have to be strong, of course, but since it could be taken on and off on the ramp I don't think it would need to swivel which simplifies the fabrication a lot.

    I don't have a vehicle where I keep my boat that can haul it so I would like a winch on the trailer so I have more options for a tow vehicle. Just a 4x4 winch with a battery box and I'd pull the cranking battery off the boat for power (it comes off the boat anyway). I suppose I would want a fairlead for the winch so that the cable is drawing in line with the tongue but the winch itself stays well out of the water. Probably mount the winch 4' up or so.

    To me this setup would be better than a hitch extender because it allows me to use someone else's truck without even putting the tires in the water and I can easily put the trailer in deep enough that I'm not fighting to get a 3' draft boat on there. Obviously the winch is going to hate the salt and there's more maintenance than a simple hitch extender but is the design sound, fundamentally? Why don't I ever see this setup?
  2. Blueknarr
    Joined: Aug 2017
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    Location: Colorado

    Blueknarr Senior Member

    Welcome to the forum.

    Your concern over not seeing simular arrangements is warranted.

    Tongue extenders both push and pull.

    Winches are great pullers but lousy pushers.

    Work out how to push the trailer into deep water with a winch and someone will nominate you for a Nobel Prize.

    Keep dreaming and experimenting.

    Good luck
    philSweet likes this.
  3. Paul Calder
    Joined: Jul 2019
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    Location: Maine

    Paul Calder New Member

    I'm not sure I see the issue here. The trailer is C-channel and plate, easily 500lbs with no enclosed air spaces, probably more like 750. I would think it will roll down the ramp under its own weight above or under water. This isn't a standard issue powerboat trailer with lots of square tubing and rubber bits. Maybe the concrete 'tread' on many ramps will catch the wheels enough to make this an issue? I don't think it will on the ramp I have in mind.
  4. Barry
    Joined: Mar 2002
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    Barry Senior Member

    You did not specify the number of tires which will provide a large degree of floatation but not enough to float the trailer
    You will have to ensure that when the boat is on the trailer that there is enough tongue weight to ensure that the higher center of gravity will not let the tongue of the trailer come up off
    the ground.
    The above may not be relevant but you certainly do not want to dump the transom of the boat on the ground part way through the extraction process

    Re a 4x4 winch
    Most US made winches use a load sensing brake that activates the brake on the inside of the drum under load. Due to the winch design, ie motor on one side with a long drive shaft that goes
    through the drum, to the planetary gear set on the opposing side that drives the drum. Warn as an example

    The brake is attached to the shaft that takes the torque from the motor to opposing side gear train. The speed of the shaft is different than the speed of the drum, due to the gear train so
    that when you are reversing the drum WHEN THE BRAKE IS ENGAGED DUE TO ITS FUNCTION OF SENSING THE LOAD, the brake has to in essence slip in the inside diameter of
    drum. This can burn out the brake or even make the drum not want to reverse with light loads which activate the brake.

    (when you reverse a winch of this configuration, WITHOUT a load, the drum is driven, and there is no load to engage the brake.

    A better suited winch that will allow the cable to be braked when reversing would be a worm gear winch, Ramsey electric, would be a better choice

    Perhaps at your loads, this will not be an issue, but with heavy loading, the brake will not last a long time
  5. DCockey
    Joined: Oct 2009
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    Location: Midcoast Maine

    DCockey Senior Member

    In theory if everything stays straight and the trailer doesn't shift sideways the wheel under the tongue won't need to swivel. In practice the ability of the wheel to swivel may be very beneficial. Trailer jacks with swivel wheels rated up to 1500 lbs are available. If you are currently in Maine then Hamilton Marine carries several. One concern with any type of wheel under the tongue would be the wheel catching on the ramp and the assembly being bent.

    With a wheel under the tongue you could do an initial test using a length of suitable rope or chain to connect the trailer and tow vehicle.

    I assume you would float the boat on and off the trailer. Ramps are generally steep enough in Maine to cope with 10' plus tides that the trailer will want to roll down the ramp into the water. If the ramp is shallow enough that the trailer does not roll down the ramp then the ramp is unlikely to be long enough to float a boat which draws 3.5 feet. With many "full tide" ramps in Maine you will probably need to launch at one quarter tide or higher to have enough submerged length of ramp. Other ramps might require even higher tide. Ramps elsewhere with small tides or no tide may not have enough length underwater or go deep enough to launch a boat drawing 3.5 feet.
  6. tpenfield
    Joined: Dec 2016
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    Location: Cape Cod, MA

    tpenfield Senior Member

    Not sure if you have done any launches of boat/trailer this way. Keeping the trailer on a straight course into the water may not be 100%, so you will want to consider the ability to steer the trailer a bit as well as winch it. A steeper ramp is better, since you won't have to go in as far. However, disconnecting and re-connecting the trailer hitch on the ramp slope may not be a slam-dunk.

    Also, a 10K lb. trailer/load presumably has brakes, so you will want to have a way to disconnect the braking system accordingly.

    FWIW - I made a trailer tongue extension 'system' for my Catalina 22 trailer (see link below). IIRC, the extension was only about 8 feet, but it saved from having to disconnect the brake line and kept the electrical harness connector from getting submerged.
    Tongue Extension System
  7. philSweet
    Joined: May 2008
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    Location: Beaufort, SC and H'ville, NC

    philSweet Senior Member

    You can't load a boat onto a loose trailer. I've seen 4 ton diesel duallies get pushed around during boat loadings. (I've also seen boats end up on the cab and hood of them when the throttle got advanced as the bow bumped the trailer's bowpost.) There isn't a dolly wheel in existence that can handle a loading.

    I managed to break a 1000 pound tongue dolly with a 300 pound boat. I'm just clever that way.

    750 pounds sounds way too light a trailer for a 5 ton boat. Like 2.5 times too light. For a 5 ton payload, you need twin 7000 pound axles or preferably a triple. Frame size should be at least 5" for the triple and 6" for the tandem. Ought to weigh about 2000 pounds empty.
    Last edited: Jul 8, 2019

  8. waikikin
    Joined: Jan 2006
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    Location: Australia

    waikikin Senior Member

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