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Re: [bolger] How would Mr Bolger update Cynthia J?

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  • Gene T.
    Graeme, Doubling or trippling the bottom will only help righting on a boat that is not flooded. Once the boat is filled, all that plywood becomes flotation
    Message 1 of 15 , Oct 6, 2006
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      Graeme,
      Doubling or trippling the bottom will only help righting on
      a boat that is not flooded. Once the boat is filled, all that plywood
      becomes flotation and will have the opposite effect. I think you need
      some dense weight down there, lead, steel, at least epoxy filled with
      something heavy. Then extra flotation to make sure you don't go right
      to the bottom! 8^D

      Sincerely,

      "A house ashore is but a boat, so poorly
      built it will not float ---- "

      ----- Original Message ----
      From: graeme19121984 <graeme19121984@...>
      To: bolger@yahoogroups.com
      Sent: Thursday, October 5, 2006 11:49:25 PM
      Subject: [bolger] How would Mr Bolger update Cynthia J?

      The designer got around to Otter ll himself, but to my knowledge
      hasn't and is, I suppose, unlikely to get around to CynthiaJ ll. So,
      guided by study of developments of other PCB&F designs over the
      years, how would Cynthia J be improved/modified? Modified, that is,
      to be a bit more suited to pursuits other than just pond picnic
      daysailing with a gaggle of fun, kids, and family aboard. To really
      be self rescueing at the least.



      RIG.
      PCB&F wrote, when considering the Beach Cat design, of the issues
      some have nowadays with the long footed gaff cat rig. I'd like to
      keep the basic long foot rig to try it for fast and weatherly, but
      there may be other worthwhile modifications. How about a Camper, or
      other tabernacle; or a Wandervogel vang for instance?

      Place a stop on the mast to bear its weight at the partner and not
      the floor, and so eliminate both the doubling of the bottom member
      of frame #1 and the through-hull bolt located there.

      Place halyards cleat on the mast and eliminate their compressive
      load transference that required the strengthening floor bolt in the
      first place.



      BOTTOM.
      Double or triple plywood layer. This should allow removal of most of
      the bottom shoes, and also the irksome inside bottom stiffening
      cleats that muck up a lovely flat cuddy floor for lying on.

      Sheath bottom in fibreglass before fixing bottom shoes etc.

      Will this be stiff enough?



      BOUYANCY/BALLAST.
      As the flooded boat is reported difficult to get to remain upright,
      and impossible to do so with the rig in place, these aspects need
      attention. The increased bottom thickness already mentioned will
      help put weight where needed, but is it enough? Transferring
      flotation situated down low, as per the underseat foam blocks, to a
      higher location also should help, but again is it enough?

      Also as in the changes from Otter to Otter ll, watertight
      compartmentalisation seems required. The cuddy should be very flood
      resistant, or watertight. Altering Frame #1 to a watertight bulkhead
      will have very little effect on cuddy space. There's still enough to
      lie down in. The space in front of the then Bulkhead #1 should
      perhaps then be made a free draining flooded well? And perhaps the
      large triangular foam block there in the bow could be done away
      with?

      Bulkhead #3 needs altering by filling in the swinging cuddy doors
      and replacing with cuddy access much higher up. Duckboard in the
      bulkhead with decktop sliding hatch; or just a deck hatch, perhaps
      hinged?

      Box-in the entire space aft of the cockpit seats from floor to rails
      and make a huge bouyancy/storage compartment with top hatch access.
      It may be more convenient to shorten the seats and box-in aft from
      Frame #4 ( how many people are to be carried anyway? You won't be
      able to stretch out on the cockpit floor any more, but a great
      galley box and cooler could be built into the forward side of that
      aft compartment.). Offset the rudder to allow a small outboard
      mounted on the transom. Recess the end of the compartment in way of
      the outboard.

      Fix foam blocks under aft compartment deck, and foam sheet under
      fore part of cuddy deck as insurance.

      Use two ballast sandbags; one beneath each seat, both shifted to
      windward side when under sail.

      LEEBOARDS.
      I'd be inclined to try assymetrics, even though it seems PCB doesn't
      think they're needed. They'd be even easier to shape, assuming the
      designed ones are not merely flat plates

      YULOH.
      Leave the outboard at home, take a yuloh and Cynthia J may just be a
      very competitive Everglades Challenge short course entrant. What do
      you think?

      What else could be done, or needs doing?

      Graeme

      http://groups.yahoo.com/group/bolger/files/CynthiaJ/

      http://groups.yahoo.com/group/Bolger2/files/Cynthia%20J/

      http://groups.yahoo.com/group/bolger_study_plans_only/files/Cynthia%
      20J./









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    • captreed48
      As ... on her ... bottom to ... capsize is ... Well....capsize is a major concern. A friend of mine capsized his Cynthia J and could not get it upright. A
      Message 2 of 15 , Oct 6, 2006
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        As
        > designed, I believe Cynthia J would, if capsized, float fairly high
        on her
        > side, supported by the cabin and the bouyancy of the mast and gaff.
        > Righting her would require a swimmer to grab the stringers on the
        bottom to
        > pull her up or, more likely, a line to parbuckle the boat up. If
        capsize is
        > a major concern,

        Well....capsize is a major concern. A friend of mine capsized his
        Cynthia J and could not get it upright. A helpful park ranger boat and
        crew couldn't either but towed the boat submerged back to the launch
        ramp. By that time my friend was very hypothermic.


        I think bouyancy tanks in each quarter or across the entire transom and
        under the seats in addition to making the cabin watertight would vastly
        improve the situation. In that case the heavier bottom would help
        right her. (Not so if the boat isn't watertight..wood floats, but not
        very high.)

        Let us know how it goes.

        Reed
      • John and Kathy Trussell
        The standard approach for recovering a capsized dinghy is to put weight on the centerboard to lever the boat back on her feet. This doesn t work with
        Message 3 of 15 , Oct 7, 2006
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          The standard approach for recovering a capsized dinghy is to put weight on the centerboard to lever the boat back on her feet. This doesn't work with leeboards. If the leeboard is on the high side, it is too high for a swimmer to reach; if it is on the low side, a swimmer can't exert much force on it. Probably the best approach is to keep a length of line fastened to the gunwale amidships. If capsize occurs, throw the line over the high side of the boat, swim around to the bottom of the boat, and use the line to try to pull the boat up (with your feet on the bottom and pulling on the line).

          Obviously a boat floating high on it's side will be easier to right than one floating low. It would be relatively simple to add a bulkhead immediately behind the seats and deck in the space for substantial added bouyancy. If the seats were made wider to meet the sides and the joint between the outer edge of the seats and the side were made watertight (with fiberglass tape set in an epoxy fillet) the seats woud also provide some bouyancy (assuming thet the boat would float high enough on her side so that the inboard edge of the seat was above water).

          To make the boat truly self righting, it is necessary to add ballast either in the form of hard ballast or water ballast. If you are going to do that, it would probably be necessary to make the curve of the bottom deeper to float the additional weight.

          Another alternative is to add a 'Birdwatcher' cabin.

          All of these modifications a) increase the amount of plywood needed, b) increase the weight of the boat (degrading performance), and c) change the concept. If you want a small, self righting boat, maybe there are better designs than Cynthia J (see PCB's Old Shoe and Supermouse designs, for his approaches).

          JohnT
          ----- Original Message -----
          From: captreed48
          To: bolger@yahoogroups.com
          Sent: Saturday, October 07, 2006 12:22 AM
          Subject: [bolger] Re: How would Mr Bolger update Cynthia J?


          As
          > designed, I believe Cynthia J would, if capsized, float fairly high
          on her
          > side, supported by the cabin and the bouyancy of the mast and gaff.
          > Righting her would require a swimmer to grab the stringers on the
          bottom to
          > pull her up or, more likely, a line to parbuckle the boat up. If
          capsize is
          > a major concern,

          Well....capsize is a major concern. A friend of mine capsized his
          Cynthia J and could not get it upright. A helpful park ranger boat and
          crew couldn't either but towed the boat submerged back to the launch
          ramp. By that time my friend was very hypothermic.

          I think bouyancy tanks in each quarter or across the entire transom and
          under the seats in addition to making the cabin watertight would vastly
          improve the situation. In that case the heavier bottom would help
          right her. (Not so if the boat isn't watertight..wood floats, but not
          very high.)

          Let us know how it goes.

          Reed






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        • graeme19121984
          Hi Reed, is that your 15July95 MAIB Capsised ! article? Good article mate. Did you know Jim Michalak now includes it in one of his catalogues? I ve liked
          Message 4 of 15 , Oct 8, 2006
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            Hi Reed,

            is that your 15July95 MAIB "Capsised !" article? Good article
            mate. Did you know Jim Michalak now includes it in one of his
            catalogues?

            I've liked Cynthia J forever (and not just because from adolescence
            on I'll always have an elevated pulse at merely the mention of the
            name Cynthia, but that's another story :)). I assumed she'd float
            alright, but when I read in the article that a repeat Bolger
            prototypes builder, a guy in Bolger's books, Tony Groves, had that
            trouble self rescueing her I sat up and took notice. Presumably,
            Tony is a competent sailor, so that's not the trouble with righting
            the boat. He would have included the designed flotation foam,
            wouldn't he? So that's not the trouble either.

            I'm not sure, but I think in addition to the rig weight, it's the
            low, under-seat flotation that would tend to keep her rolling over.
            I think the foam block in the bow would float the bow end a bit, but
            would be almost neutral as to orientation. Then there's an awful lot
            of water to bail, a problem if it's warm; let alone icy.

            In addittion to extra watertightness, chambers and sandbags, maybe
            a little weight bolted to the lower bulkhead 3# frame member would
            help? A little weight to aid in self rescue, not self right.

            For self righting, how about a lifting Single Handed Schooner type
            keel at bulkhead #3? You could possibly go coastwise then. Put a
            bridgedeck across there to support it that's boxed in either side
            for, say, more cockpit coolers. ( Yeah.., the CJ rig could be
            dropped into Micro, but CJ has her own certain cuteness in styling
            that's not only in her perky rig.) If that seems too much space
            subtracted from the cockpit, CJ with her plumb sides would really
            suit the outside, ballasted, twin daggerboards from Centennial ll;
            if the loss of the pivoting leeboards positioning flexibility could
            be stood. Right there, at the high sided cockpit rail, that type of
            lightly ballasted daggerboard would be a cinch to raise or lower.
            The flare that causes some trouble in their use on Centennial ll is
            absent.

            Did Tony report his experience to PCB, as it seems both PCB and
            Bernie Wolfard were reluctant to include Cynthia J in the CSD
            catalogue?

            It would at first appear a quick and easy thing for PCB to improve
            the self rescuing of CJ before catalogue inclusion, but he didn't
            (note: self -rescuing, not -righting). CJ seems to be from an
            earlier period where PCB was happy to hop between dinkum sharpie
            designs arising from either his own flow theory, or Chapelleian
            aprioristic postulate. Perhaps a time came when he was no longer
            able to do so, and would not update such designs having firmly moved
            to a new sharpie paradigm. He updated Bolger Flow Theory conforming
            Otter #231 much later to Otter ll #375, but couldn't do so to
            Chapellian Cynthia J #289. If an exception proves the rule then he
            has a bob each way with the later Jesse Cooper #389; but even here
            he then could not update, and moved instead entirely to the new
            paradigm with AS29 #547.

            Graeme

            --- In bolger@yahoogroups.com, "captreed48" <captreed@...> wrote:
            >
            > As
            > > designed, I believe Cynthia J would, if capsized, float fairly
            high
            > on her
            > > side, supported by the cabin and the bouyancy of the mast and
            gaff.
            > > Righting her would require a swimmer to grab the stringers on
            the
            > bottom to
            > > pull her up or, more likely, a line to parbuckle the boat up.
            If
            > capsize is
            > > a major concern,
            >
            > Well....capsize is a major concern. A friend of mine capsized his
            > Cynthia J and could not get it upright. A helpful park ranger
            boat and
            > crew couldn't either but towed the boat submerged back to the
            launch
            > ramp. By that time my friend was very hypothermic.
            >
            >
            > I think bouyancy tanks in each quarter or across the entire
            transom and
            > under the seats in addition to making the cabin watertight would
            vastly
            > improve the situation. In that case the heavier bottom would help
            > right her. (Not so if the boat isn't watertight..wood floats, but
            not
            > very high.)
            >
            > Let us know how it goes.
            >
            > Reed
            >
          • graeme19121984
            ... needed, b) increase the weight of the boat (degrading performance), and c) change the concept. If you want a small, self righting boat, maybe there are
            Message 5 of 15 , Oct 8, 2006
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              --- In bolger@yahoogroups.com, "John and Kathy Trussell"
              <jtrussell2@...> wrote:
              >
              > All of these modifications a) increase the amount of plywood
              needed, b) increase the weight of the boat (degrading performance),
              and c) change the concept. If you want a small, self righting boat,
              maybe there are better designs than Cynthia J (see PCB's Old Shoe
              and Supermouse designs, for his approaches).
              >
              > JohnT

              Hi John,

              all you say is true, and the increased plywood pile would nearly
              complete AS19, a boat designed to serve close to the original
              intention, I think, of a group day sailer with a cuddy, but with
              much deck space for sprawling. However, for instance, in AS19 PCB&F
              wanted to get away from people being confined to the cockpit and I
              would like one that provides deep shelter. As PCB wrote about
              Cynthia J it is rare to find a boat nowadays that you can sit in. He
              has studied Herreshoff's Rozinante closely, and as Herreshoff
              observed about the Rozinante that cockpit type tops all.

              The sublime Anhinga could be got out from a slightly smaller pile of
              wood than AS19 requires. She has the best cockpit. Wonderful.
              However, she carries capsize and flooding concerns similar to the
              unrevised Marth Jane. Doing away with the aft ventilation, and a
              truly watertight hatch to the aft compartment might fix. The
              ventilation as designed is very elegant, as is the truly amazing
              system of apparent aft ballast COG shifting athwartships with
              associated negative pitching that leads to the flooding concern as a
              knock on effect.

              Modification to Cynthia J might be easier, and she has that rig. The
              boom on a gallows provides a great ridge pole for a cockpit tent.
              Makes a nice place to sit out a sunny day under with lots of
              ventilation and cooled sustenance close by. Carry the tent forward
              to the mast and both cudddy hatches could be off in the rain.

              Graeme
            • John and Kathy Trussell
              This is an example of conflicting demands. Big, deep, open cockpits are wonderful things for a crew to enjoy, but they are subject to flooding in a knockdown
              Message 6 of 15 , Oct 8, 2006
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                This is an example of conflicting demands. Big, deep, open cockpits are wonderful things for a crew to enjoy, but they are subject to flooding in a knockdown or from a breaking wave. Bolger has expressed concerns about what would happen if Rozinante were flooded (he thinks she would sink due to the weight of her ballast). Possible solutions to the vulnerability of large, open cockpits are: a) a large volume of enclosed, watertight cabin and/or bulkheaded and decked area behind the cockpit; or b) enclosing the cockpit in a Birdwatcher type cabin.

                I wish there was a way to have all the features that I want in a boat with none of the drawbcks, but I haven't found it yet!

                John T
                ----- Original Message -----
                From: graeme19121984
                To: bolger@yahoogroups.com
                Sent: Sunday, October 08, 2006 11:06 AM
                Subject: [bolger] Re: How would Mr Bolger update Cynthia J?


                --- In bolger@yahoogroups.com, "John and Kathy Trussell"
                <jtrussell2@...> wrote:
                >
                > All of these modifications a) increase the amount of plywood
                needed, b) increase the weight of the boat (degrading performance),
                and c) change the concept. If you want a small, self righting boat,
                maybe there are better designs than Cynthia J (see PCB's Old Shoe
                and Supermouse designs, for his approaches).
                >
                > JohnT

                Hi John,

                all you say is true, and the increased plywood pile would nearly
                complete AS19, a boat designed to serve close to the original
                intention, I think, of a group day sailer with a cuddy, but with
                much deck space for sprawling. However, for instance, in AS19 PCB&F
                wanted to get away from people being confined to the cockpit and I
                would like one that provides deep shelter. As PCB wrote about
                Cynthia J it is rare to find a boat nowadays that you can sit in. He
                has studied Herreshoff's Rozinante closely, and as Herreshoff
                observed about the Rozinante that cockpit type tops all.

                The sublime Anhinga could be got out from a slightly smaller pile of
                wood than AS19 requires. She has the best cockpit. Wonderful.
                However, she carries capsize and flooding concerns similar to the
                unrevised Marth Jane. Doing away with the aft ventilation, and a
                truly watertight hatch to the aft compartment might fix. The
                ventilation as designed is very elegant, as is the truly amazing
                system of apparent aft ballast COG shifting athwartships with
                associated negative pitching that leads to the flooding concern as a
                knock on effect.

                Modification to Cynthia J might be easier, and she has that rig. The
                boom on a gallows provides a great ridge pole for a cockpit tent.
                Makes a nice place to sit out a sunny day under with lots of
                ventilation and cooled sustenance close by. Carry the tent forward
                to the mast and both cudddy hatches could be off in the rain.

                Graeme






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              • pvanderwaart
                As a former Cynthia J. owner, I have mixed bag of comments and reactions. I never capsized mine, but I realized that it would be a major mess if it ever
                Message 7 of 15 , Oct 8, 2006
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                  As a former Cynthia J. owner, I have mixed bag of comments and
                  reactions. I never capsized mine, but I realized that it would be a
                  major mess if it ever happened. My boat had the flotation as designed,
                  and eventually I bought, but never installed, some additional
                  flotation. My idea was to run a section of the rigid baulk as
                  purchased vertically in the cabin. I suppose that would have been
                  about 10" x2' section, about 3' long. My idea was that it would lift
                  the boat while it was on its side. Just a guess; no calculations, no
                  experience. In a letter to me when I bought the plans, PCB suggested
                  lining the interior of the cabin top with foam.

                  As to standing on a leeboard to right the boat, I think that could
                  result in major damage.

                  In the MAIB that arrived at my house yesterday, PCB says he would now
                  give the boat a mast slot like the Chebacco, etc. I did find stepping
                  the mast to be a little closer to the end of my range of capabilities
                  than I liked. He also suggested reducing the size of the cabin.

                  As to major modifications to the design, I wonder if it makes much
                  sense to take that approach. PCB's ply boat techniques have changed a
                  lot, and a new design to the same spec would be a lot different. And
                  there is little point in modifying it in the direction of Micro.

                  Peter
                • graeme19121984
                  ... Peter, thanks for this news, you ve given cause for me now to subscribe. This is a must read. Then I ll read again your considered Cynthia J observations
                  Message 8 of 15 , Oct 9, 2006
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                    --- In bolger@yahoogroups.com, "pvanderwaart" <pvanderwaart@...> wrote:
                    >
                    > ...In the MAIB that arrived at my house yesterday,...

                    Peter, thanks for this news, you've given cause for me now to
                    subscribe. This is a must read. Then I'll read again your considered
                    Cynthia J observations based on use, here, and in the files.

                    Cheers
                    Graeme
                  • graeme19121984
                    Gene, Here s a rough comparison of two flat irons as is. No account taken of where the c.o.g. in each boat actually is. 400lbs added for crew and stuff.
                    Message 9 of 15 , Oct 11, 2006
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                      Gene,

                      Here's a rough comparison of two "flat irons" as is. No account
                      taken of where the c.o.g. in each boat actually is. 400lbs added for
                      crew and stuff. Michalak's estimate used for total constructed boat
                      weight of 35 lbs and 50 lbs per sheet respectively for 1/4 or 3/8
                      ply. No rig weight included. Go stormin' in CJ? Easy mod?

                      Cynthia J
                      Displacement to LWL 130
                      Hull Speed 5.01
                      Sail Area to Displacement 27.48
                      LWL to Beam 2.55
                      Motion Comfort 8.96
                      Capsize Ratio 2.37
                      Sailing Category racer
                      Pounds/Inch 275





                      Storm Petrel

                      Displacement to LWL 130
                      Hull Speed 5.19
                      Sail Area to Displacement 13.3
                      LWL to Beam 2.9
                      Motion Comfort 10.95
                      Capsize Ratio 2.08
                      Sailing Category cruiser/racer
                      Pounds/Inch 277

                      http://www.image-ination.com/sailcalc.html

                      Graeme




                      --- In bolger@yahoogroups.com, "Gene T." <goldranger02-boats@...>
                      wrote:
                      >
                      > Graeme,
                      > Doubling or trippling the bottom will only help righting on
                      > a boat that is not flooded. Once the boat is filled, all that
                      plywood
                      > becomes flotation and will have the opposite effect. I think you
                      need
                      > some dense weight down there, lead, steel, at least epoxy filled
                      with
                      > something heavy. Then extra flotation to make sure you don't go
                      right
                      > to the bottom! 8^D
                      >
                      > Sincerely,
                      >
                      > "A house ashore is but a boat, so poorly
                      > built it will not float ---- "
                      >
                    • graeme19121984
                      Ok, Ive read that MAIB article now and it hasn t changed my perspective on Cynthia J very much, if any. The boat would still be better, from a self rescuing
                      Message 10 of 15 , Oct 16, 2006
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                        Ok, Ive read that MAIB article now and it hasn't changed my
                        perspective on Cynthia J very much, if any. The boat would still be
                        better, from a self rescuing and comfort point of view, for updates
                        made along the lines of Otter ll and similar. Yep, there is little
                        point in modifying Micro in the current Cynthia J direction, and
                        losing the stability and offshore capability, but Cynthia J would
                        benefit enormously from small attention to bouyancy and ballast.

                        PCB suggests the increased bottom thickness, and some extra
                        flotation in the quarters, also the 290lbs water ballast Rick
                        included to stop her going over and flooding like Martha Jane un-
                        revised, and Anhinga. I think a bow well would be better than a mast
                        slot alone as he suggests. The forward frame, middle bulkheads,
                        companion way, and storage mentioned in earlier posts would be
                        worthwhile little modifications IMHO.

                        In this article I think PCB looks at this hull as a big family's day
                        sailing dinghy rather than the comfy camp cruiser she might be. He
                        observes that more than one up, indeed with only two crew, it is
                        hard to trim the boat as it should be. If the seating places two
                        crew's weight too far aft of the C.O.B might not correct placement
                        of stuff stored in the cuddy balance it?

                        On the other hand, if the cabin is shortened to allow forward
                        extension of the side seats a comfortable cabin is lost for little
                        gain. This hull is not of his advanced sharpie type as PCB implies
                        in the article. It is a flat iron, as I understand the term. It
                        follows H I Chapelle's doctrine for sharpies of a long, dead-flat
                        run to the turn of the bottom. As such, crew weight placed further
                        than just a bit forward of where the seats are now will have the
                        undesirable effect of burying the chine forward with all the bad
                        follow-on effects that PCB has warned of so often. So, if crew sits
                        forward extra weight will have to be placed in the stern, and the
                        cabin is gone. With more crew this could be easily arranged, and
                        would suit, but it then is a very high sided dinghy.

                        As a cuddy camper this boat would be so good. Awaken, coffee, then
                        so easily bulk sail is hoisted to ghost off on the day's adventure
                        with the breeze hardly stirred in morning's first light.

                        Graeme



                        --- In bolger@yahoogroups.com, "pvanderwaart" <pvanderwaart@...>
                        wrote:
                        > ...In the MAIB that arrived at my house yesterday, PCB says he
                        would now
                        > give the boat a mast slot like the Chebacco, etc. I did find
                        stepping
                        > the mast to be a little closer to the end of my range of
                        capabilities
                        > than I liked. He also suggested reducing the size of the cabin.
                        >
                        > As to major modifications to the design, I wonder if it makes much
                        > sense to take that approach. PCB's ply boat techniques have
                        changed a
                        > lot, and a new design to the same spec would be a lot different.
                        And
                        > there is little point in modifying it in the direction of Micro.
                        >
                        > Peter
                        >
                      • John and Kathy Trussell
                        Graeme-- It would be nice if all the things we want could be combined in a very short boat. Here are the problems that must be addressed in very smallboats.
                        Message 11 of 15 , Oct 17, 2006
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                          Graeme--

                          It would be nice if all the things we want could be combined in a very short boat. Here are the problems that must be addressed in very smallboats.

                          1) On small boats, crew weight makes up a very large portion of the boat's total displacement. Placement of crew weight has a major impact on performance.

                          2) A 'cabin' needs to be long enough so that an adult can lie down--for average folks, this is around 75 ". If two people are to sleep in the cabin, the sleeping area should be between 42'' and 48' wide at the head and at least 36" wide at the foot.

                          3) There are three possible ways to get a decent cabin in a very short boat. You can have a cockpit behind the cabin; this will put crew weight in the back of the boat, possibly trimming the boat down by the stern. You can stack the cockpit on top of part of the cabin (examples are Peephen, Lynx, and the origunal West Wight Potter). You can combine the cabin and cockpit, sailing from inside the cabin (Birdwatcher, Supermouse, and several of Michalak's designs).

                          4) One of the things that drove the Cynthis J design was to have a very simple boat which was styled to look sort of like a Cape Cod Catboat. (And I think that PCB was very successful in this regard.) I know that Cynthia J's looks were (and are) one of the main reasons that I continue to admire this design. The desire for this catboat effect precludes a Birdwatcher cabin (which PCB tried, without success on the Flatfish design).

                          If I were going to play naval architect and revamp Cynthia J, I would move the main bulkhead forward and add a bulkhead and deck to the aft end of the cockpit. This would move crew weight forward. I would then close in the seats and cut holes in the bulkhead to create two quarter berths (these would not be very satisfactory and would often be damp, but what can you expect). Lastly, I would beef up the bottom to as much as an inch, adding a fair amount of ballast. Even with all this, Cynthis J is a sailor for sheltered waters, and I would consider her a character daysailor with the capability for an occassional one night cruise.

                          JohnT
                          ----- Original Message -----
                          From: graeme19121984
                          To: bolger@yahoogroups.com
                          Sent: Monday, October 16, 2006 10:51 PM
                          Subject: [bolger] Re: How would Mr Bolger update Cynthia J?


                          Ok, Ive read that MAIB article now and it hasn't changed my
                          perspective on Cynthia J very much, if any. The boat would still be
                          better, from a self rescuing and comfort point of view, for updates
                          made along the lines of Otter ll and similar. Yep, there is little
                          point in modifying Micro in the current Cynthia J direction, and
                          losing the stability and offshore capability, but Cynthia J would
                          benefit enormously from small attention to bouyancy and ballast.

                          PCB suggests the increased bottom thickness, and some extra
                          flotation in the quarters, also the 290lbs water ballast Rick
                          included to stop her going over and flooding like Martha Jane un-
                          revised, and Anhinga. I think a bow well would be better than a mast
                          slot alone as he suggests. The forward frame, middle bulkheads,
                          companion way, and storage mentioned in earlier posts would be
                          worthwhile little modifications IMHO.

                          In this article I think PCB looks at this hull as a big family's day
                          sailing dinghy rather than the comfy camp cruiser she might be. He
                          observes that more than one up, indeed with only two crew, it is
                          hard to trim the boat as it should be. If the seating places two
                          crew's weight too far aft of the C.O.B might not correct placement
                          of stuff stored in the cuddy balance it?

                          On the other hand, if the cabin is shortened to allow forward
                          extension of the side seats a comfortable cabin is lost for little
                          gain. This hull is not of his advanced sharpie type as PCB implies
                          in the article. It is a flat iron, as I understand the term. It
                          follows H I Chapelle's doctrine for sharpies of a long, dead-flat
                          run to the turn of the bottom. As such, crew weight placed further
                          than just a bit forward of where the seats are now will have the
                          undesirable effect of burying the chine forward with all the bad
                          follow-on effects that PCB has warned of so often. So, if crew sits
                          forward extra weight will have to be placed in the stern, and the
                          cabin is gone. With more crew this could be easily arranged, and
                          would suit, but it then is a very high sided dinghy.

                          As a cuddy camper this boat would be so good. Awaken, coffee, then
                          so easily bulk sail is hoisted to ghost off on the day's adventure
                          with the breeze hardly stirred in morning's first light.

                          Graeme

                          --- In bolger@yahoogroups.com, "pvanderwaart" <pvanderwaart@...>
                          wrote:
                          > ...In the MAIB that arrived at my house yesterday, PCB says he
                          would now
                          > give the boat a mast slot like the Chebacco, etc. I did find
                          stepping
                          > the mast to be a little closer to the end of my range of
                          capabilities
                          > than I liked. He also suggested reducing the size of the cabin.
                          >
                          > As to major modifications to the design, I wonder if it makes much
                          > sense to take that approach. PCB's ply boat techniques have
                          changed a
                          > lot, and a new design to the same spec would be a lot different.
                          And
                          > there is little point in modifying it in the direction of Micro.
                          >
                          > Peter
                          >






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                        • graeme19121984
                          ... Me too. Graeme
                          Message 12 of 15 , Oct 17, 2006
                          • 0 Attachment
                            --- In bolger@yahoogroups.com, "John and Kathy Trussell"
                            <jtrussell2@...> wrote:
                            >
                            >I know that Cynthia J's looks were (and are) one of the main
                            >reasons that I continue to admire this design.

                            <long sigh> Me too.

                            Graeme
                          • pvanderwaart
                            On the subject of crew position, I agree with the notion that having the crew a bit too far forward is worse that having it aft. As designed, crew weight
                            Message 13 of 15 , Oct 18, 2006
                            • 0 Attachment
                              On the subject of crew position, I agree with the notion that having
                              the crew a bit too far forward is worse that having it aft. As
                              designed, crew weight causes the boat to pivot about a point near the
                              forward end of the lwl, and the new immersed shape is a heavier
                              displacement version of the original. (Note PCB kept the stern up out
                              of the water to make this possible.) I found the boat went upwind very
                              well with skipper plus two lightish crew, or one heavy one. The low
                              seating position is a plus.

                              I only sailed the boat solo once or twice, and was surprised by how
                              quickly she heeled with a light load.

                              If you look at the plans carefully, you will note the extreme
                              simplicity that PCB had in mind. He did not draw any blocks or
                              mechanical advantages, leeboard pendants, lifts or stops for the
                              swinging rudder blade, etc. Partly, I think this was to save drawing
                              board time. Partly, just for simplicity. My boat took 300-400 hours by
                              a average-skilled professional in a well equipped boatshop.
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