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Convenient way to tow a boat from a yacht

Discussion in 'Technical Discussion' started by theav8r, Nov 24, 2008.

  1. theav8r

    theav8r New Member

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    Is there an especially convenient way to tow a fun/performance boat from a yacht ??
    Let's say you have a 90ft yacht and you want to bring along a 30ft fun/performance boat .....
  2. K1W1

    K1W1 Senior Member

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    Hi,

    Welcome to YF.

    If you are going to tow a 30' Performance Boat behind your 90' Yacht you will need to take several precautions.

    A towing bridle is an important piece of kit. If you are serious about long distance towing you will be best served by having some strong points added to your boat purely for towing.

    The standard cleats and or trailer fitting are not designed to tow the boat long distance at sea. The use of a towing point anywhere above the chine will also cause chafing damage and extra wear to the towing lines.

    If you are towing overnight and deep sea the addition of a radar reflector to your towed boat is also not a bad idea because if the tow parts unseen you have more chance of finding it with something that will stand out on radar.

    Also carefully pick your weather as towing places a lot more strain on the boat in general the last thing you want to be doing is towing it in marginal conditions, the fuel consumption of the boat doing the towing will also go up some.

    You should also check with your insurance Co to see if you are already covered for this practice or if you need additional cover.
  3. revdcs

    revdcs Senior Member

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    You can also reckon on cutting your cruising speed by at least half, if not two thirds! That might be okay if you are just popping to the next bay, but towing another vessel of that size is not really practical under normal crusing conditions.
  4. NYCAP123

    NYCAP123 Senior Member

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    If you're talking about cruising the Bahamas there's not much problem, but in any kind of weather you may prefer to send it with a crewmember (Give him a little bonus for getting his butt kicked). If you're talking about running long distance (say up the coast) then put it on a truck. Also, reinforce the bow eye (or add one) to the towed vessel. Seperate the vessels before entering any close quarters situations. That means you'll be one crewmember short for docking. P.S. That bridal and long heavy duty tow line will be a lot to stow.
  5. Pascal

    Pascal Senior Member

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    it's pretty common around here (so Fl / Bahamas), you see quite a few of these center console fitted with a SS plate, 3 to 4" wide and extending up to 12" on each side to reinforce the tow eye. It obviously limits the speed often down to hull speed and you need adjust the length to get the smoothest ride inthe wake.

    monitoring the tow with a CC camera isn't a bad idea either
  6. MacMcL

    MacMcL Senior Member

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    Pascal,

    I saw one of those towing bridles that had been thru bolted with counter sunk bolt heads. The boat and the tow got caught in a storm. The bracket came right off. If you mount one of those tow brackets, use backer plates and flat head bolts. Yes, counter sunk bolts make for a neater appearance, but they do not hold up in rough weather. Any one seen a 33' Contender floating around out there?
  7. NYCAP123

    NYCAP123 Senior Member

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    Doubt that had much to do with the bridal or the countersunk bolts. Although the bow is usually a pretty well reinforced section it's designed to withstand push more than pull. Most likely the whole eye got pulled out. So it bears repeating that this is not for running in rough water.
  8. K1W1

    K1W1 Senior Member

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    Hi,

    The poster you are replying to in your post says quite clearly that the bracket came off and lays a lot of the blame on the use of countersunk bolts.

    Are you suggesting that he doesn't know what he is talking about of needs a visit to his eye doctor?

    I would agree with the suggestion to use flat or hex head bolts and washers with a backing plate on the inside with Nyloc nuts and flat washers there as well.
  9. Pascal

    Pascal Senior Member

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    indeed, he's not talking about an eye, but those large plates. I'm no engineer or rocket scientist but it seems pretty clear that counter sunk bolts woudl not have the strength of flat or hex...

    as to beefy backing plates, it's seems pretty obvious that you'd add the on the inside of the hull as well, but we all know how yards and builders love to cut corners!

    In addition to CC TV, i think that if i was going to rig a large tender/CC to be towed, i'd add a wire in the briddle/tow line to rig an "oh s..t we lost the tender" alarm!
  10. NYCAP123

    NYCAP123 Senior Member

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    Actually he began talking about the bridle and later alluded to the fact that there was no backer plate. No 33' boat's bow eye is going to take that for long in rough weather without backer plates whether the bolts are countersunk or not.
  11. Pascal

    Pascal Senior Member

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    Bow eyes usually don't have any bolts, they bolted on the other side with a backing plate. not sure what the exact name for those "bridle plates" are although they are shape as a bridle... this is where you need heavy backing plates but as important flat bolts with washers on the outside. otherwise, the metal might be too thin and the countersunk bolt heads could pull thru.
  12. PropBet

    PropBet Senior Member

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    K1W1 pretty much hit all of the important points.

    If you have not set it up before, you'll want to check with someone who has and insure that your cleats and rigging are correct. Getting set up is one important part, and then getting off / going in tow is your next critical stage. Take a little practice, and care.

    We do it regularly. This is a 32' center console Century in tow.

    Attached Files:

  13. Marmot

    Marmot Senior Member

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    "... this is where you need heavy backing plates but as important flat bolts with washers on the outside. otherwise, the metal might be too thin and the countersunk bolt heads could pull thru."

    CS bolt heads are OK in tension so long as the counterbore is less than 70 percent of the material thickness ( I would shoot for less than 50). Also, and this is probably the most applicable element in this discussion, CS fasteners should not be used in shear. Eyes mounted either side of the stem to allow for a bridle connection will almost certainly be in shear rather than tension. A single eye mounted on the centerline of the stem will be loaded cyclically in shear as the towed vesse ... shears. Eyes mounted on deck are definitely feeling shear loads.
  14. Capt J

    Capt J Senior Member

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    I've done it before. A boat I occassionally worked on towed a 26' Whaler from a 74' Sunseeker and at cruise (24 knots). You're going to want a very reinforced larger bow eye on the tender. A stout short piece of line with shackel on the tender (usually around 10')comes in very very handy for unhooking in heavy seas and you just pull the end up and secure on the bow of the tender. Then a spectrabraid tow line, I think the proper ratio is 1.5 times the towboats length. And a spectrabride bridal for the stern of the towing vessel, you can usually get away with the vessels cleats on the towing vessel as they are usually pretty stout on a 70'+ vessel. A company in Fort Lauderdale does a lot of these and can set it all up. I forget the name of them right now. Depending on the towing vessel and stern wake many times you'll have to tow at 12 knots or under. Some fast boats with a lot of power like a sportfish can get away with towing at near cruise speeds.

    It's relatively easy, however you'll have to unhook before going into marina's and ports usually and likewise, hook up after leaving port....... I did once have to swim to the tender in 10' seas with a lifevest on, to get into the tender and unhook it because it was too rough to safely get close enough to it to jump in it to disconnect it........NOT FUN. Also people that tow at cruise speeds will usually drag 30' of heavy chain 1" or so with 10' of lighter nylon rope 3/8" or even less. in front of it (a breakaway in case your in shallow water and the chain hooks something) behind the tender, this keeps enough drag to keep the tender tracking straight without all of the drag of the 2+ outboard motors.....

    Outboard boats are much easier to tow. If you get into towing an inboard boat you have to lock down the shafts, and it's recommended that you remove the propellors also, otherwise you're pulling a lot of drag. It also never seems to work out right with inboard boats towing them......

    Also, ANYONE who has lost a tender in rough seas obviously was not maintaining a proper radar watch. If you cannot see a 32' center console trailing off behind you on radar, it's either not tuned right or you're not paying attention or both.

    Also I wouldn't get too greedy with the size of the vessel you are towing. If it's a 80' yacht I wouldn't go much past 26' for the towed vessel.......100+ feet and you can tow a 30'. If you get too much weight back there, a following sea can be downright scary.
  15. NYCAP123

    NYCAP123 Senior Member

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    Thank you Capt. J for a very informative answer. You pretty much covered all the bases. I learned a few things.
  16. K1W1

    K1W1 Senior Member

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    Hi,

    Reading a lot of what has been posted above is not what Poster No 1 asked about.

    Big bolts. big plates , washers, big head bolts, 5200 joints and you will be good to go within 24 hrs of 5200 application. Prove me wrong.
  17. Capt Bill11

    Capt Bill11 Senior Member

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    Actually, what he asked was: "Is there an especially convenient way to tow a fun/performance boat from a yacht ??"

    And the short answer is, no, there is not a convenient way to tow a big tender.

    Unless it's behind some one elses boat. :)

    While it's well worth doing, it can be a PITA.

    Now if you have one of those built in power winch tow line systems I guess that lessens the PITA factor. And using Spectra in your tow line and bridle system sure helps. But as some one else mentioned, sooner or later it's going to kick up and some one will have to go in the water to unhook the **** thing.
  18. Garry Hartshorn

    Garry Hartshorn Senior Member

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    I have done a little towing over the years and just about everthing said I agree with. Except for the spectra, I know it's strong thats not the issue. I have always used polypropelene because it floats usually about 1 1/2" for a 27 ft tender, and I have never sucked it into a wheel. But I have seen more than once that problem with other types of line.
  19. Capt Bill11

    Capt Bill11 Senior Member

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    Spectra floats.

    "With outstanding toughness and extraordinary visco-elastic properties, Spectra® fiber can withstand high-load strain-rate velocities. Light enough to float, it also exhibits high resistance to chemicals, water, and ultraviolet light. It has excellent vibration damping, flex fatigue and internal fiber-friction characteristics, and Spectra® fiber's low dielectric constant makes it virtually transparent to radar."
  20. Capt J

    Capt J Senior Member

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    Yes Spectra floats, and it's a heck of a lot better working with and storing then polypropelene. But, in the end is it worth it to tow a tender. The short answer is YES.

    We were able to see 4x the distance and 10x the amount of places in the tender then we would've been able to in the yacht. We could get in and out of many of the islands in the Bahamas, that you could only get close enough to see with binoculars in the yacht. In 5 days, we were able to go ALL, from Paradise Island. We did the Berry's, The Abacos, The Exumas, etc. etc. At 40-50 mph, they were all short hops......less then 2 hours running time. It was really easy to stop for lunch, jump in and hit another island......see a cool spot and snorkle.......a very up close and personal way of doing things that you could've never done with a 15' Inflatable tender.

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