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14-knot wall

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  • trbyah
    14-knot Wall This was my first season with a Weta and I absolutely love it. However, I seem to have hit a wall at about 14 knots that I can t seem to break
    Message 1 of 8 , Aug 30, 2012
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      14-knot Wall

      This was my first season with a Weta and I absolutely love it. However, I seem to have hit a wall at about 14 knots that I can't seem to break through.

      I've had the boat out in what I would estimate to be 20 knot winds and see the same behavior each time. On a broad reach, flying the screecher, the boat handles beautifully as I pass through 12 and then 13 knots. At that point, the leeward ama starts to tuck under and I have to bear off to keep from completely burying the forward beam. This isn't a heeling issue; the bow is being driven down. If I hold my line rather than bear off, the bow of the main hull will head toward submersion. My SpeedPuck confirms each time that the max I can hit is just under or over 14 knots. This happens either solo or carrying a crewmember. It also happens to a less dramatic extent without the screecher, on a beam or a broad reach. I'd summarize it by saying "13+ knots equals bow down".

      It seems to me it's either a rigging or a handling issue. Here's what I've tried...

      * After seeing this behavior with the side stays rigged in the third hole from the bottom as Chris Kitchen recommended, I dropped down to the second hole from the bottom to get even more mast rake. There was no noticeable change in behavior.

      * There's certainly no lack of tension in the head stay, jib halyard, and cunningham. I generally put quite a bit of tension on the screecher halyard, too, although Chris says that's not critical.

      * I've attached the mainsheet and jib sheets in various holes, without noticeable effect.

      Anything else to try when rigging?

      As for handling, I'm sitting as far aft as possible and generally as far out on the tramp as possible. Based on the telltales, the main and jib seem to be trimmed reasonably but I do wonder about the screecher. I don't think I'm overtrimming it but it's possible I am.

      Any advice would be appreciated. Thank you.

      Tom
      #546 on Lake Winnipesaukee, NH
    • eric e
      that s been pretty much my experience too the weta gets to 14knots reaching reasonable easy in medium winds but once there, basically all it s righting moment
      Message 2 of 8 , Aug 30, 2012
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        that's been pretty much my experience too

        the weta gets to 14knots reaching reasonable easy in medium winds

        but once there, basically all it's righting moment is used up and it tries to trip over the float bow

        to go faster then you would need to be sailing a much deeper course, to get more main hull bow buoyancy working for you

        that will mean strong winds so you are planing on the last 1.5 meter of the mainhull, like an 18ft skiff

        also you'd need to get further back and out, extra-hiking straps? with the rig raked all the way back

        or even Dave's "double-damned style" with the sidestay going direct to the hull fittings and the adjusters left off

        i haven't been able to string that all together yet

        not actually sure it's worth it just to go another 1-2knots? faster...



        --- On Fri, 8/31/12, trbyah <trbyah@...> wrote:

        From: trbyah <trbyah@...>
        Subject: [Weta-Trimarans] 14-knot wall
        To: Weta-Trimarans@yahoogroups.com
        Date: Friday, August 31, 2012, 4:34 AM
















         









        14-knot Wall



        This was my first season with a Weta and I absolutely love it. However, I seem to have hit a wall at about 14 knots that I can't seem to break through.



        I've had the boat out in what I would estimate to be 20 knot winds and see the same behavior each time. On a broad reach, flying the screecher, the boat handles beautifully as I pass through 12 and then 13 knots. At that point, the leeward ama starts to tuck under and I have to bear off to keep from completely burying the forward beam. This isn't a heeling issue; the bow is being driven down. If I hold my line rather than bear off, the bow of the main hull will head toward submersion. My SpeedPuck confirms each time that the max I can hit is just under or over 14 knots. This happens either solo or carrying a crewmember. It also happens to a less dramatic extent without the screecher, on a beam or a broad reach. I'd summarize it by saying "13+ knots equals bow down".



        It seems to me it's either a rigging or a handling issue. Here's what I've tried...



        * After seeing this behavior with the side stays rigged in the third hole from the bottom as Chris Kitchen recommended, I dropped down to the second hole from the bottom to get even more mast rake. There was no noticeable change in behavior.



        * There's certainly no lack of tension in the head stay, jib halyard, and cunningham. I generally put quite a bit of tension on the screecher halyard, too, although Chris says that's not critical.



        * I've attached the mainsheet and jib sheets in various holes, without noticeable effect.



        Anything else to try when rigging?



        As for handling, I'm sitting as far aft as possible and generally as far out on the tramp as possible. Based on the telltales, the main and jib seem to be trimmed reasonably but I do wonder about the screecher. I don't think I'm overtrimming it but it's possible I am.



        Any advice would be appreciated. Thank you.



        Tom

        #546 on Lake Winnipesaukee, NH
      • Bruce Fleming
        “As for handling, I m sitting as far aft as possible and generally as far out on the tramp as possible.” My suggestion: it’s time to get off the tramp!
        Message 3 of 8 , Aug 30, 2012
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          “As for handling, I'm sitting as far aft as possible and generally as far
          out on the tramp as possible.”



          My suggestion: it’s time to get off the tramp!



          1) Rig a hiking strap between the safety tether and mainsheet anchor
          points.



          2) Suspend the strap off the cockpit floor with some ¼” bungee laced
          across the cockpit in the same fittings as the piece used to suspend the
          lower mainsheet fiddle block. This helps you get your feet under it when you
          need to use it.



          3) When you get back on the water, unfurl the kite and work on ‘heating
          it up’ and gradually diving down with the speed. Remember that your main
          should be sheeted in more than you think. It will power up with the increase
          in apparent wind.



          4) Get your butt off the tramp and sit on the rear quarter of the vaka,
          the main hull, instead of on the ama, with your feet hooked under the strap.
          Take a deep breath and slide your rear end over the edge of the hull behind
          the beam frame, and hike a bit. This takes some courage the first time you
          do this, if you’re not accustomed to full-on hiking like Laser sailors, but
          it works by doing many things:



          + shifting your weight aft, pitching the bow up, and functionally reducing
          wetted surface area on the vaka,



          + pitching the leeward aka up, so it no longer digs in. Instead, it pops up
          and rides over the water, increasing righting moment.



          + effectively raking the rig back as the bow rises, (maybe directing a
          little bit of lift up instead of forward?



          + stuffing the rudder a little lower in the water, reducing the tendency to
          cavitate at speeds above 12 (which is a problem on my boat)





          The boat should break past your 14 kt barrier and get you closer to…who
          knows? Frankly, this is my half-baked theory of why it works, but I know it
          does!



          I can’t take credit for it. I’m not the originator—I saw Chris Kitchen
          sitting off the rear quarter of the vaka without a hiking strap during a
          visit to San Fran. I sailed one race in heavy air the next year and
          attempted the same technique, but got a lower leg entangled in the mainsheet
          system during a crash jibe and fell off the boat, being dragged by the foot
          still tied into the boat. I’m very lucky it didn’t blow out my knee.
          Therefore, I realized I needed to add a strap to do this right. With two
          kids recently graduated from car seats in 3 different cars, I had plenty of
          surplus webbing/straps to do this myself.



          Last thought: Be careful. I don’t think a hiking strap was expected to be
          rigged when Chris and Roger developed the boat design and chose the
          fittings, so adding one is something you do at your own risk.





          Aloha,



          Bruce Fleming

          Akahele!, #276

          San Diego, California



          [Non-text portions of this message have been removed]
        • Robert S.
          Interesting, it seems that I have finally justified my weight (100kg). Bruce, as a low weight sailor :) relies on skill and knowledge to make his fly... My all
          Message 4 of 8 , Aug 31, 2012
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            Interesting, it seems that I have finally justified my weight (100kg).
            Bruce, as a low weight sailor :) relies on skill and knowledge to make his
            fly... My all time favourite photo is the one of him flying the main hull :)

            In the right conditions, I have had no problem busting the 14kts (gps) and
            have clocked 16.9 in little or no tide effect. This was in about 20 kts,
            flattish sea, and on a two sail reach - totally blind due to spray -
            perfect sailing conditions :)

            I have done well over 15 sustained - both solo and two up - yes, it tries
            to dig in, but getting out / back as far as possible, and staying ready to
            bear away reduces the fear factor - as does not clearing the main. I think
            I am at 3 holes from the bottom on the shrouds too.

            I have played with the in-hull hiking strap, but strong winds are so rare
            here (dubai) that it's not worth the bother, as it is apparently best for
            sailing really deep downwind in a blow..

            Eat more pizza... Hike out further,...

            R..




            On Friday, 31 August 2012, Bruce Fleming wrote:

            > **
            >
            >
            > �As for handling, I'm sitting as far aft as possible and generally as far
            > out on the tramp as possible.�
            >
            > My suggestion: it�s time to get off the tramp!
            >
            > 1) Rig a hiking strap between the safety tether and mainsheet anchor
            > points.
            >
            > 2) Suspend the strap off the cockpit floor with some �� bungee laced
            > across the cockpit in the same fittings as the piece used to suspend the
            > lower mainsheet fiddle block. This helps you get your feet under it when
            > you
            > need to use it.
            >
            > 3) When you get back on the water, unfurl the kite and work on �heating
            > it up� and gradually diving down with the speed. Remember that your main
            > should be sheeted in more than you think. It will power up with the
            > increase
            > in apparent wind.
            >
            > 4) Get your butt off the tramp and sit on the rear quarter of the vaka,
            > the main hull, instead of on the ama, with your feet hooked under the
            > strap.
            > Take a deep breath and slide your rear end over the edge of the hull behind
            > the beam frame, and hike a bit. This takes some courage the first time you
            > do this, if you�re not accustomed to full-on hiking like Laser sailors, but
            > it works by doing many things:
            >
            > + shifting your weight aft, pitching the bow up, and functionally reducing
            > wetted surface area on the vaka,
            >
            > + pitching the leeward aka up, so it no longer digs in. Instead, it pops up
            > and rides over the water, increasing righting moment.
            >
            > + effectively raking the rig back as the bow rises, (maybe directing a
            > little bit of lift up instead of forward?
            >
            > + stuffing the rudder a little lower in the water, reducing the tendency to
            > cavitate at speeds above 12 (which is a problem on my boat)
            >
            > The boat should break past your 14 kt barrier and get you closer to�who
            > knows? Frankly, this is my half-baked theory of why it works, but I know it
            > does!
            >
            > I can�t take credit for it. I�m not the originator�I saw Chris Kitchen
            > sitting off the rear quarter of the vaka without a hiking strap during a
            > visit to San Fran. I sailed one race in heavy air the next year and
            > attempted the same technique, but got a lower leg entangled in the
            > mainsheet
            > system during a crash jibe and fell off the boat, being dragged by the foot
            > still tied into the boat. I�m very lucky it didn�t blow out my knee.
            > Therefore, I realized I needed to add a strap to do this right. With two
            > kids recently graduated from car seats in 3 different cars, I had plenty of
            > surplus webbing/straps to do this myself.
            >
            > Last thought: Be careful. I don�t think a hiking strap was expected to be
            > rigged when Chris and Roger developed the boat design and chose the
            > fittings, so adding one is something you do at your own risk.
            >
            > Aloha,
            >
            > Bruce Fleming
            >
            > Akahele!, #276
            >
            > San Diego, California
            >
            > [Non-text portions of this message have been removed]
            >
            >
            >


            [Non-text portions of this message have been removed]
          • trbyah
            Eric, ... For me, the wow-factor doubles with every two knots above 10. 14 is incredible compared to 12, so I just HAVE to see what 16 is like. 18? I may not
            Message 5 of 8 , Aug 31, 2012
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              Eric,

              > not actually sure it's worth it just to go another 1-2knots? faster...

              For me, the wow-factor doubles with every two knots above 10. 14 is incredible compared to 12, so I just HAVE to see what 16 is like. 18? I may not want to go there ...

              Tom
              #546 on Lake Winnipesaukee, NH
            • bjarthur123
              i ve rigged an alternative to the hiking strap. instead of attaching the tether to the D-ring on the cockpit floor, i anchor the tether to point a just
              Message 6 of 8 , Sep 2 5:34 AM
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                i've rigged an alternative to the hiking strap. instead of attaching the tether to the D-ring on the cockpit floor, i anchor the tether to point a just between the hatch and the daggerboard.

                one can still hike outboard as normal when going upwind, but it is now impossible to fall overboard to aft. it is also possible to crawl onto the foredeck to fix something gone awry without having to unclip.

                the new attachment point is a Y-shaped line going from the mast to each of the forward beams. see the new photos i've uploaded in the "358 chesapeake bay" folder titled "safety tether".

                it's a bit too far forward to hike off the stern as bruce described, but perfect for sitting on the stern quarter of the main hull just aft of the beam.

                the impetus for the re-design was an man overboard incident we had when a prospective 70-year old took a boat out for a test ride. in 15-20 knot winds he slipped while sitting on the edge of the tramp and was drug by the boat for about 10 minutes. could barely keep his head above water but didn't want to let go as the boat wasn't his and it was headed for a rocky shore.


                i've also uploaded a few pics of two other mods to the boat: replaced all metal shackles with homemade soft shackles, and added another beam to the road trailer after a couple welds broke.

                ben, #358
                chesapeake bay


                --- In Weta-Trimarans@yahoogroups.com, "Bruce Fleming" <wavejump@...> wrote:
                > 1) Rig a hiking strap between the safety tether and mainsheet anchor
                > points.
                >
                > 2) Suspend the strap off the cockpit floor with some ¼" bungee laced
                > across the cockpit in the same fittings as the piece used to suspend the
                > lower mainsheet fiddle block. This helps you get your feet under it when you
                > need to use it.
                >
                > 3) When you get back on the water, unfurl the kite and work on `heating
                > it up' and gradually diving down with the speed. Remember that your main
                > should be sheeted in more than you think. It will power up with the increase
                > in apparent wind.
                >
                > 4) Get your butt off the tramp and sit on the rear quarter of the vaka,
                > the main hull, instead of on the ama, with your feet hooked under the strap.
                > Take a deep breath and slide your rear end over the edge of the hull behind
                > the beam frame, and hike a bit. This takes some courage the first time you
                > do this, if you're not accustomed to full-on hiking like Laser sailors, but
                > it works by doing many things:
                >
                > + shifting your weight aft, pitching the bow up, and functionally reducing
                > wetted surface area on the vaka,
                >
                > + pitching the leeward aka up, so it no longer digs in. Instead, it pops up
                > and rides over the water, increasing righting moment.
                >
                > + effectively raking the rig back as the bow rises, (maybe directing a
                > little bit of lift up instead of forward?
                >
                > + stuffing the rudder a little lower in the water, reducing the tendency to
                > cavitate at speeds above 12 (which is a problem on my boat)
                >
                > The boat should break past your 14 kt barrier and get you closer to…who
                > knows? Frankly, this is my half-baked theory of why it works, but I know it
                > does!
                >
                > I can't take credit for it. I'm not the originator—I saw Chris Kitchen
                > sitting off the rear quarter of the vaka without a hiking strap during a
                > visit to San Fran. I sailed one race in heavy air the next year and
                > attempted the same technique, but got a lower leg entangled in the mainsheet
                > system during a crash jibe and fell off the boat, being dragged by the foot
                > still tied into the boat. I'm very lucky it didn't blow out my knee.
                > Therefore, I realized I needed to add a strap to do this right. With two
                > kids recently graduated from car seats in 3 different cars, I had plenty of
                > surplus webbing/straps to do this myself.
                >
                > Last thought: Be careful. I don't think a hiking strap was expected to be
                > rigged when Chris and Roger developed the boat design and chose the
                > fittings, so adding one is something you do at your own risk.
              • Mark Iverson
                So did the man buy a boat? : ) ... [Non-text portions of this message have been removed]
                Message 7 of 8 , Sep 2 7:10 AM
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                  So did the man buy a boat? : )



                  On Sep 2, 2012, at 5:34 AM, "bjarthur123" <bjarthur123@...> wrote:

                  >
                  >
                  > i've rigged an alternative to the hiking strap. instead of attaching the tether to the D-ring on the cockpit floor, i anchor the tether to point a just between the hatch and the daggerboard.
                  >
                  > one can still hike outboard as normal when going upwind, but it is now impossible to fall overboard to aft. it is also possible to crawl onto the foredeck to fix something gone awry without having to unclip.
                  >
                  > the new attachment point is a Y-shaped line going from the mast to each of the forward beams. see the new photos i've uploaded in the "358 chesapeake bay" folder titled "safety tether".
                  >
                  > it's a bit too far forward to hike off the stern as bruce described, but perfect for sitting on the stern quarter of the main hull just aft of the beam.
                  >
                  > the impetus for the re-design was an man overboard incident we had when a prospective 70-year old took a boat out for a test ride. in 15-20 knot winds he slipped while sitting on the edge of the tramp and was drug by the boat for about 10 minutes. could barely keep his head above water but didn't want to let go as the boat wasn't his and it was headed for a rocky shore.
                  >
                  > i've also uploaded a few pics of two other mods to the boat: replaced all metal shackles with homemade soft shackles, and added another beam to the road trailer after a couple welds broke.
                  >
                  > ben, #358
                  > chesapeake bay
                  >
                  > --- In Weta-Trimarans@yahoogroups.com, "Bruce Fleming" <wavejump@...> wrote:
                  > > 1) Rig a hiking strap between the safety tether and mainsheet anchor
                  > > points.
                  > >
                  > > 2) Suspend the strap off the cockpit floor with some ¼" bungee laced
                  > > across the cockpit in the same fittings as the piece used to suspend the
                  > > lower mainsheet fiddle block. This helps you get your feet under it when you
                  > > need to use it.
                  > >
                  > > 3) When you get back on the water, unfurl the kite and work on `heating
                  > > it up' and gradually diving down with the speed. Remember that your main
                  > > should be sheeted in more than you think. It will power up with the increase
                  > > in apparent wind.
                  > >
                  > > 4) Get your butt off the tramp and sit on the rear quarter of the vaka,
                  > > the main hull, instead of on the ama, with your feet hooked under the strap.
                  > > Take a deep breath and slide your rear end over the edge of the hull behind
                  > > the beam frame, and hike a bit. This takes some courage the first time you
                  > > do this, if you're not accustomed to full-on hiking like Laser sailors, but
                  > > it works by doing many things:
                  > >
                  > > + shifting your weight aft, pitching the bow up, and functionally reducing
                  > > wetted surface area on the vaka,
                  > >
                  > > + pitching the leeward aka up, so it no longer digs in. Instead, it pops up
                  > > and rides over the water, increasing righting moment.
                  > >
                  > > + effectively raking the rig back as the bow rises, (maybe directing a
                  > > little bit of lift up instead of forward?
                  > >
                  > > + stuffing the rudder a little lower in the water, reducing the tendency to
                  > > cavitate at speeds above 12 (which is a problem on my boat)
                  > >
                  > > The boat should break past your 14 kt barrier and get you closer to…who
                  > > knows? Frankly, this is my half-baked theory of why it works, but I know it
                  > > does!
                  > >
                  > > I can't take credit for it. I'm not the originator—I saw Chris Kitchen
                  > > sitting off the rear quarter of the vaka without a hiking strap during a
                  > > visit to San Fran. I sailed one race in heavy air the next year and
                  > > attempted the same technique, but got a lower leg entangled in the mainsheet
                  > > system during a crash jibe and fell off the boat, being dragged by the foot
                  > > still tied into the boat. I'm very lucky it didn't blow out my knee.
                  > > Therefore, I realized I needed to add a strap to do this right. With two
                  > > kids recently graduated from car seats in 3 different cars, I had plenty of
                  > > surplus webbing/straps to do this myself.
                  > >
                  > > Last thought: Be careful. I don't think a hiking strap was expected to be
                  > > rigged when Chris and Roger developed the boat design and chose the
                  > > fittings, so adding one is something you do at your own risk.
                  >
                  >


                  [Non-text portions of this message have been removed]
                • bjarthur123
                  no. his wife wouldn t let him after that. still sails his rhodes bantam every morning though. shame b/c it was his second test ride and he was pretty
                  Message 8 of 8 , Sep 4 4:45 AM
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                    no. his wife wouldn't let him after that. still sails his rhodes bantam every morning though. shame b/c it was his second test ride and he was pretty seriously in the market. that would've been our fifth boat at the same club.

                    a simpler solution to the Y anchor point might be to tie the tether to the daggerboard handle line. will try it out next time i single hand.

                    ben #358
                    chesapeake bay




                    --- In Weta-Trimarans@yahoogroups.com, Mark Iverson <rustysunners@...> wrote:
                    >
                    > So did the man buy a boat? : )
                    >
                    >
                    >
                    > On Sep 2, 2012, at 5:34 AM, "bjarthur123" <bjarthur123@...> wrote:
                    >
                    > >
                    > >
                    > > i've rigged an alternative to the hiking strap. instead of attaching the tether to the D-ring on the cockpit floor, i anchor the tether to point a just between the hatch and the daggerboard.
                    > >
                    > > one can still hike outboard as normal when going upwind, but it is now impossible to fall overboard to aft. it is also possible to crawl onto the foredeck to fix something gone awry without having to unclip.
                    > >
                    > > the new attachment point is a Y-shaped line going from the mast to each of the forward beams. see the new photos i've uploaded in the "358 chesapeake bay" folder titled "safety tether".
                    > >
                    > > it's a bit too far forward to hike off the stern as bruce described, but perfect for sitting on the stern quarter of the main hull just aft of the beam.
                    > >
                    > > the impetus for the re-design was an man overboard incident we had when a prospective 70-year old took a boat out for a test ride. in 15-20 knot winds he slipped while sitting on the edge of the tramp and was drug by the boat for about 10 minutes. could barely keep his head above water but didn't want to let go as the boat wasn't his and it was headed for a rocky shore.
                    > >
                    > > i've also uploaded a few pics of two other mods to the boat: replaced all metal shackles with homemade soft shackles, and added another beam to the road trailer after a couple welds broke.
                    > >
                    > > ben, #358
                    > > chesapeake bay
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