505 type dinghy as a cruiser

Discussion in 'Sailboats' started by milessmiles, Oct 3, 2013.

  1. PAR
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    PAR Yacht Designer/Builder

    My bad, though a cruiser typical would carry a cuddy or cabin. Maybe a raid boat or camp cruiser, would be a better term for your intended uses. Most will think of the term cruiser as you've described it, casual sailing, but this usually means Fidel the wonder dog, the better half and a cooler full of beer, maybe some camping gear, etc. Please excuse my assumptions.

    You can use a ballast bulb, if you like, though considerable reinforcement at the case and boat's centerline will be necessary. You'll still heel quite a bit (it's the nature of the hull form), but you will not have to hike as much.
  2. milessmiles
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    milessmiles Junior Member

    Thanks for reply. Reinforcement of the centreboard case was my fear, how would that be done. My ballast torpedo I want to hang on short wires so when the boat is heeling it hangs verical rather than carrying on the centreboard/sail angle. I think it might collect debris though. I think all up weight of boat will be approx 140kg and crew weight should be140/200kg so what weight do you think the ballast torpedo would need to be to have a very positive effect, am I right to assume not that heavy as will be on bottom of centreboard.
  3. bregalad
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    bregalad Senior Member

    That's not a good idea from several standpoints:

    •If it hangs vertical it won't be contributing to the righting moment. It's just dead weight along for the ride.

    • Normal canting keels are 'winched' out to windward to increase the righting moment. Several really high stress points are involved in designing such a keel. Probably not stresses you would want to try to accommodate in your boat.

    • If you did manage to fit that type of keel to a 505 you be in instant heartburn if caught aback, the weight now being to leeward in an open boat with low form stability.

    IMO ... reduce the size of the rig a bit and go sailing. Either it will meet your needs and you can have fun, or deficiencies and solutions will become more apparent. They may involve putting a different hull under the rig.
  4. PAR
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    PAR Yacht Designer/Builder

    Bregalad is correct, for ballast to be effective, it must cant to windward. Dangling on wires will do absolutely nothing, the boat will just roll and flop over. It has to be fixed to an appendage, which could live in your case. You could raise and lower this bulb with the appendage, though some tackle will likely be required.

    To improve the righting ability of a fixed or retractable bulb, you can cant it to windward, though as pointed out, this can be a difficult engineering exercise to retro fit into your boat.
  5. gggGuest
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    gggGuest ...

    Don't forget though Chris, the original Sharpie was barking heavy, much more so than the Australian version, which might affect things.

    I guess the key sentence from the original post is "prototype like a 505" and "like a 505" might mean many things. If it means "about the same size as a 505 but with one inch of rocker" then increasing the displacement greatly might have unhappy results. If on the other hand the boat was designed with light airs in mind, has generous rocker, and a lightweight crew had trouble getting both ends in the water at the same time then the outlook for sailing it with more weight in would be considerably rosier.

    I suppose the thing that concerns me most about this as a project is the experience of the prospective owner. "Frankenboats" can be very entertaining projects, and teach you a hell of a lot, but really developing one is in many ways as difficult as developing a new boat, with the added complication that what you are starting with may be the wrong platform. So there are kinda three possibilities. One is that the boat will roughly work fairly easily, one is that it could be made to vaguely work given an awful lot of time effort and money, and the third possibility is that it will never be good no matter how much effort is put in. This development process will inevitably be even harder for someone with only moderate dinghy experience than for someone with a great deal.

    We can also say that the development of a prototype into a first class racing boat for the mass manufacturers is about a two year process, which probably involves a number of partial redesigns on the way. See published accounts of the 29er for instance to back this up.

    So for someone fairly new to sailing a project like this has a pretty low chance of being a success without spending an awful lot of time and money. We can be pretty sure of this by considering how many full on professional design projects have turned out to be less than successful long term - few new dinghy classes seem to gain long term popularity.

    Now, if you're prime interest is in playing with boats on the shore (and why the hell not) then this may not matter. I remember seeing in another forum recently the observation that many plans one can buy on the internet seem to be of boats that are for building more than sailing (and again why the hell not). However if your prime aim is to get out on the water and go sailing, rather than fiddle with boats on the beach then I reckon you'll be far better off with something that already works and doesn't need alteration to fit your needs. And what's more it will probably be a damn sight cheaper in the long run, because developing boats absorbs cash like a sponge!
  6. Herman
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    Herman Senior Member

    I would definately not take disabled or crippled people abord something that is not suitable for it. The hull shape of a 505 makes for fun racing by 2 fit people, but whatever you do with it, it will never be the safe and stable boat you want.

    If you run into a mishap, you might regret things.
  7. CT 249
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    CT 249 Senior Member

    Agree with all that, Gg. But re the Usual 20/Sharpie and the one-off converted Sharpie; both used on the 77kg (IIRC) "Lightweight Sharpie" hull and scantlings, not the heavweight's construction. As noted below, the Sharpie is a tiny boat for a 20 footer and the fact that the hull has been used successfully for a micro cruiser (with cabin) seems to show that the 505 could work as a cruising dayboat, even if it's not ideal for the reasons you noted.

    PAR: After sailing today I was looking down at the dinghy park and noting once again how small the Sharpie is for a 20 footer; the 420 next door didn't look small against it. The nearest 5-0 looked a bigger boat but I couldn't get both in the same visual frame. It was similar to the Fireball and Contender that were lined up with the Tasar; the longer boats were smaller in every way bar LOA.I'm far from convinced that a 20 footer that is much skinnier, lighter and lower is a 'bigger boat' than a wider, heavier, higher boat just 2'6" shorter. It's hard to say from sailing them 'cause our Sharpie has three crew.
  8. John Perry
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    John Perry Senior Member

    Yes, of course you can do it!

    I disagree with most of the other posters here, including the couple of professionals that have replied. Yes, you can go cruising in a racing dinghy such as a 505 and you don't need to make a lot of modifications to the boat. I base that on decades of experience of fairly long distance cruising in a 4.5m (15foot) open sailing dinghy, including many passages across the English Channel.

    The main thing I think you need to do is to have an efficient arrangement for reefing the sails, and you need to be able to reef down further than most people think necessary. As a rough guide, I think you should be able to reef your mainsail to something like one third of its maximum area and its probably a good idea to carry a smaller jib as well as the normal jib. When your mainsail is fully reefed you may find it best not to set a jib at all (I find that is the case with my boat). That means that you need to have an arrangement to remove or furl the jib without having to struggle onto the foredeck - you said you have a roller furler on the forestay so that sounds good. In addition to having effective reefing for your mainsail you may like to consider carrying a smaller flat cut mainsail (we do) for use when windy weather is anticipated. I dont think this is essential, at least not for a tryout cruise, but a small mainsail may set better than a deeply reefed full size one.

    Another thing you probably need is some auxiliary propulsion, if only for when you have to maneuver the boat in close quarters. (Some harbors and marinas will actually prohibit you from entering under sail). I am a bit of a sailing purist so I will not recommend an outboard, which apart from anything else would be an absolute pain to stow away on a boat like yours. With two reasonably fit persons you may manage with a couple of paddles but oars are better. The beam of the 505 is almost the same as the wayfarer and I know that the wayfarer is not a nice boat for rowing, but oars are still the best option I think. You may need sealed rowlock sockets if the bouyancy tanks extend to the gunwhale.

    I am not sure what you mean when you talk about hanging ballast under your boat on wires! Maybe you have some revolutionary new idea in mind and within a few years we will all be copying you, on the other hand maybe not! Think about the drag coefficient of circular section wires under the water, also the weed catching potential.

    Generally, I dont think adding a deep ballast keel to an existing racing dinghy is a good idea - just having cruising equipment on board is going to increase the displacement to much more than it was designed to be. On a boat that is designed to be sailed fairly upright, a deep ballast keel will not be all that useful for normal sailing, the main reason to include it would I think be to assist recovery from capsize. You have to judge whether that advantage is worth the extra weight, lots of work to build it, probable difficulty in raising the keel in a hurry when in shallow water.

    For shelter at night I think a cabin would be heavy and would excessively restrict you moving around the boat during the day time. You just dont need it - we use a simple boom tent.

    I suspect that the 505 has less inherent form stability than, for example, the wayfarer dinghy that is a popular choice for cruising. You are going to need to use your body weight to advantage just as you would for racing. However, I dont think your boat is any worse in that respect than the numerous narrow beam traditional style wood built 'sail and oar' designs that are now being promoted for open boat cruising. After all, people are successfully going cruising in canoes fitted with sails - the main thing is to match the sail area to the available righting moment.
  9. SukiSolo
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    SukiSolo Senior Member

    You should also check out the Paul Hobson designed K1 made in the UK. Although a single hander with self tacking jib, it has 60Kg of 'wing' keel. I can assure you it is a nicely balanced boat that handles well and goes upwind well and it planes on reaches. If you can use some of the ideas from the K1 in modifying a 505 hull you may get something to work OK.
    I have only sailed it on a lake so cannot vouch for behaviour in a big seaway but do not doubt it has no real vices.
  10. milessmiles
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    milessmiles Junior Member

    Thanks everybody, lots of helpful input. I shall leave the hull alone, go for smaller jib that is self tacking and roller furling, smaller main reefable to about a third of what the original would of been. If possible I may mount the boom a little higher. This plan should get me out sailing quickly and I can learn about the boats handling, play about with adjusting the rigging and see what my mates capabilities are. Cheers
  11. Skyak
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    Skyak Senior Member

    Our work is done. Great solution.

    About cruising in small boats -I saw this site the other day about a couple cruising the east coast and the Bahamas in a simple little sharpie -not to prove anything, just for the joy of it. It tilts the idea of ho much boat is needed.

  12. milessmiles
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    milessmiles Junior Member

    Wow, thats inspirational
  13. PAR
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    PAR Yacht Designer/Builder

    Most cruisers wouldn't find crossing the English channel in a 505 cruising, but more white knuckle stuff for the really serious about getting wet and testing their skill. The same would be true of long passages in a micro. Yes, some would (a small percentage), but when you mention cruising, these aren't the craft typically pictured in their imaginations.

    The best thing you can do is go sailing, so you can find out what type of cruiser you actually are. You may indeed be a micro or raid type of sailor, but I don't think you know this yet. Cruisers are developed through evolution. You don't know what you want or like, until you've discovered what you don't, which requires a fair bit of experience. You first cruising boat will be vastly different from your last, as a result of this self imposed evolution.

    Go sailing, have fun, take weekend trips and see what you need, which will be the beginning of your development as a cruiser.
  14. DCockey
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    DCockey Senior Member

    A ballast torpedo hanging on wires will have exactly the same effect on static stability as if it was fastened to the boat with the CG of the ballast torpedo in line with the positions the wires would be fastened to the hull in the same fore/aft position.

  15. Skyak
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    Skyak Senior Member

    I am a big fan of small human/sail powered craft, and simplified living in general.

    The things that fry my mind are;
    -where do you find a woman for these adventures? And she's the one writing so positively! I think long and hard before bringing a date for a couple hour float down the river. Nobody asked where they poop -every time I tell a woman about sailing more than a day they ask.
    -Three months cruising the Bahamas in in a skinny 14 ft sharpie -and they are PALE? I passed though in 3 weeks, dead of winter, in a 47ft and I was tanner. That cabin would violate the Geneva convention for POWs.
    -I would love to see their log for the Bahamas vs the weather -what is the tipping point of sitting in that tiny space rocking for the day or sailing? As sailors say -schedules kill.
    -4 to 5 knot average speed crossings? That's pretty good in a 14 ft that doesn't shift ballast isn't it? Must be a tail wind.
    -In that limited space they carry 4, 9, and 25lb anchors, and a drogue, and a folding Dingy? What the hell, throw in two parrots in two cages!

    It is inspiring. As PAR says, you need to figure what kind of cruiser you are. I think I could design a rig that would only weigh ~350lbs that could do what they do but 'comfy' to the point it is no hardship. Something I could drag up a beach or off a sand bar. My dream is to design such a craft that can be carried on a plane or bus.
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