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Re: [Michalak] Re: Woobo Revisited

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  • jhargrovewright2@juno.com
    Nels, That is the way I build now. 1/8 ply glued to 1/2 or 3/4 blue foam from Low s. If it really needs more strength several layers. I use FG tape on
    Message 1 of 25 , Aug 18, 2013
      Nels, That is the way I build now. 1/8" ply glued to 1/2" or 3/4" blue foam from Low's. If it really needs more strength several layers. I use FG tape on the plywood joints inside and out and apply the foam very carefully fitted, after the hull is built. I use a shop vac to vacuum bag or a venture vacuum pump to laminate depending on the arrangement size and difficulty. It is very difficult to get 100% of the panel laminated without vacuum. The interior surface is cloth painted on the foam. I use cheap bed sheets. It works and lasts lasts longer than I would anticipate. It becomes a very stiff sandwich panel since the cloth is in tension in an impact or water pressure load. The foam is comfortable to sit and sleep on and is warm in the cold. JIB
      ---------- Original Message ----------
      From: "prairiedog2332" <nelsarv@...>





      [Non-text portions of this message have been removed]
    • Samantha Roberts
      Hi Nels, For a quick hull surface area estimate, I went from the body plan online (I don t have plans for Woobo) and estimate about 78 sq feet for the hull
      Message 2 of 25 , Aug 19, 2013
        Hi Nels,

        For a quick hull surface area estimate, I went from the body plan online (I don't have plans for Woobo) and estimate about 78 sq feet for the hull skin (no bulkheads, decking or other structure).  That should be pretty close if the indicated dimensions of 15' x 4' mean 15'-0" x 4'-0".

        To reduce weight, what do you think of a SOF version of Woobo built fuselage-style?

        -- Sam



        ________________________________
        From: prairiedog2332 <nelsarv@...>


         
        Great information Chris. Thing is I am a bit hung up on the square
        sterned motor canoe thing now in my older age. Never had one but have
        been out on ones as long as 25+ feet with the RCMP up in Arctic. Wood
        and canvas and a Big OB of course and I am thinking a 2 HP Honda
        probably. I have canoed many miles with pointy stern canoes with a
        kicker mounted off to the side on a outboard mount and don't care for
        that option. Very inefficient really. The little self-draining well also
        seems a really good option.

        Any estimate on the area of the hull itself on a Woobo? That way I
        could estimate the hull weight with various material options.

        [Non-text portions of this message have been removed]
      • prairiedog2332
        Thanks John, sounds like the way to go. What kind of adhesive do you use for the laminating? I never thought of bed sheets, but I bet the cheap ones that are
        Message 3 of 25 , Aug 19, 2013
          Thanks John, sounds like the way to go. What kind of adhesive do you
          use for the laminating? I never thought of bed sheets, but I bet the
          cheap ones that are made from polyester would work great. So you have
          not only a built-in mattress but bottom sheet as well:-) Not only would
          it be warmer than plywood but may drum less in a chop I bet.

          I don't quite understand why the 12' Mixer is only at the 90 lb. mark
          and Woobo, 3' longer is 150 lb. - both with identical cross-sections
          from the Piccup Pram - only narrowed 6".

          http://www.duckworksbbs.com/ProductDetails.asp?ProductCode=JM-Mixer
          <http://www.duckworksbbs.com/ProductDetails.asp?ProductCode=JM-Mixer>


          Covered decking and hatches really add a lot of weight and might be
          shortened if one is carrying waterproof portage packs anyway but then
          the top covered shelter would have to made longer. One could add a
          fabric "tonneau cover" under which the packs could be stored and
          accessed from inside the closed in top or lifted out when portaging.
          Things really can get complicated quickly.


          Nels



          --- In Michalak@yahoogroups.com, "jhargrovewright2@..." wrote:
          >
          > Nels, That is the way I build now. 1/8" ply glued to 1/2" or 3/4"
          blue foam from Low's. If it really needs more strength several layers.
          I use FG tape on the plywood joints inside and out and apply the foam
          very carefully fitted, after the hull is built. I use a shop vac to
          vacuum bag or a venture vacuum pump to laminate depending on the
          arrangement size and difficulty. It is very difficult to get 100% of
          the panel laminated without vacuum. The interior surface is cloth
          painted on the foam. I use cheap bed sheets. It works and lasts lasts
          longer than I would anticipate. It becomes a very stiff sandwich panel
          since the cloth is in tension in an impact or water pressure load. The
          foam is comfortable to sit and sleep on and is warm in the cold. JIB
          > ---------- Original Message ----------
          > From: "prairiedog2332" nelsarv@...
          >
          >
          >
          >
          >
          > [Non-text portions of this message have been removed]
          >



          [Non-text portions of this message have been removed]
        • jhargrovewright2@juno.com
          Nels, I am considerably weaker as I age sooo weight becomes more than just convenience. I have used epoxy for laminating but am experimenting with TB-III. It
          Message 4 of 25 , Aug 19, 2013
            Nels, I am considerably weaker as I age sooo weight becomes more than just convenience. I have used epoxy for laminating but am experimenting with TB-III. It seems to work well. Decks and compartments do add a lot of weight and take up room but they both stiffen up the torsional rigidity of the boat. That is not so important now with the way we build boats today....with an adhesive on each join. Good design requires good compromise. The tonneau type cover can work well if constructed thoughtfully. I find them difficult to get "right". The weight of the two boats seem off, which one? or both. I do not have the plan so can't calculate.
            The fabric/foam/paint works well for me but many or most would not like it.....but I get to make the choices, don't I. JIB
            ---------- Original Message ----------
            From: "prairiedog2332" nelsarv@...



            Thanks John, sounds like the way to go. What kind of adhesive do you
            use for the laminating? I never thought of bed sheets, but I bet the
            cheap ones that are made from polyester would work great. So you have
            not only a built-in mattress but bottom sheet as well:-) Not only would
            it be warmer than plywood but may drum less in a chop I bet.

            I don't quite understand why the 12' Mixer is only at the 90 lb. mark
            and Woobo, 3' longer is 150 lb. - both with identical cross-sections
            from the Piccup Pram - only narrowed 6".

            http://www.duckworksbbs.com/ProductDetails.asp?ProductCode=JM-Mixer
            <http://www.duckworksbbs.com/ProductDetails.asp?ProductCode=JM-Mixer>

            Covered decking and hatches really add a lot of weight and might be
            shortened if one is carrying waterproof portage packs anyway but then
            the top covered shelter would have to made longer. One could add a
            fabric "tonneau cover" under which the packs could be stored and
            accessed from inside the closed in top or lifted out when portaging.
            Things really can get complicated quickly.

            Nels

            --- In Michalak@yahoogroups.com, "jhargrovewright2@..." wrote:
            >
            > Nels, That is the way I build now. 1/8" ply glued to 1/2" or 3/4"
            blue foam from Low's. If it really needs more strength several layers.
            I use FG tape on the plywood joints inside and out and apply the foam
            very carefully fitted, after the hull is built. I use a shop vac to
            vacuum bag or a venture vacuum pump to laminate depending on the
            arrangement size and difficulty. It is very difficult to get 100% of
            the panel laminated without vacuum. The interior surface is cloth
            painted on the foam. I use cheap bed sheets. It works and lasts lasts
            longer than I would anticipate. It becomes a very stiff sandwich panel
            since the cloth is in tension in an impact or water pressure load. The
            foam is comfortable to sit and sleep on and is warm in the cold. JIB
            > ---------- Original Message ----------
            > From: "prairiedog2332" nelsarv@...
            >
            >
            >
            >
            >
            > [Non-text portions of this message have been removed]
            >

            [Non-text portions of this message have been removed]







            [Non-text portions of this message have been removed]
          • prairiedog2332
            Fine Woodworking did some glue tests quite awhile back now and they showed regular TB had a higher sheer strength than TBII or III but they of course had
            Message 5 of 25 , Aug 19, 2013
              Fine Woodworking did some glue tests quite awhile back now and they
              showed regular TB had a higher sheer strength than TBII or III but they
              of course had perfectly fitting clamped joints and no testing about
              joining wood to foam board. I am wondering if a person ran some shallow
              kerfs in the back of the structural foam and then when pressed into
              place against the curved hull sections, the kerfs would open and a glue
              slurry might ooze up to fill them, and make for some nice smooth joints
              with no gaps and the foam board sort of "locked" in place?


              Taking Sam's hull area estimate of 78 sq. ft. and my weight calcs for
              3mm Baltic birch and 1" foam board. Those materials come to about 41
              pounds for a bare hull. Of course that is bare with no framing, decks, 4
              oz glass, epoxy, paints and bed sheets:) I am thinking cedar for frames,
              slotted whales, aluminum tubes for spars, but a heavier transom for
              the motor.

              Sam also asked about SOF but I don't have a lot of faith in them for
              sailing. First to get them stiff enough and second a sailboat doesn't
              have very good brakes if something sharp suddenly appears. I have sailed
              in a Klepper Aerius II rigged to spec with the sloop rig and it was not
              as great as advertised going to weather. Keeping the stays from sagging
              almost impossible, so we ended up accepting a tow. Plus there are a lot
              of sharp rocks in places I might go, plus the SOF's I have seen are not
              that light. Also I had a Folbot that was heavier than my 18' canoe and
              still have a 15' Pakboat. The worst canoes for getting scraped open by
              rocks were the Grumman aluminum lightweights.


              I think JIB's ideas are opening a whole new field of potential design
              options when one takes weight into consideration as we get older and
              feebler. We have some older cowgirls and canoeists around here that are
              really stronger than I and would be great crew. I'll do the cooking if
              they help with the lifting. "Tote that barge, lift that bale." LOL.

              Nels

              --- In Michalak@yahoogroups.com, "jhargrovewright2@..." wrote:
              >
              > Nels, I am considerably weaker as I age sooo weight becomes more than
              just convenience. I have used epoxy for laminating but am experimenting
              with TB-III. It seems to work well. Decks and compartments do add a lot
              of weight and take up room but they both stiffen up the torsional
              rigidity of the boat. That is not so important now with the way we build
              boats today....with an adhesive on each join. Good design requires good
              compromise. The tonneau type cover can work well if constructed
              thoughtfully. I find them difficult to get "right". The weight of the
              two boats seem off, which one? or both. I do not have the plan so can't
              calculate.
              > The fabric/foam/paint works well for me but many or most would not
              like it.....but I get to make the choices, don't I. JIB




              [Non-text portions of this message have been removed]
            • jhargrovewright2@juno.com
              Nels, Just make up a small panel let it dry well... then try to tear apart. Plenty of shear strength. I sand the foam with very coarse sandpaper before
              Message 6 of 25 , Aug 19, 2013
                Nels, Just make up a small panel let it dry well... then try to tear apart. Plenty of shear strength. I "sand" the foam with very coarse sandpaper before applying the glue....actually just drag it over. I have gone through the kerf, poking holes, knife cuts and see no difference. The important, critical, necessary thing to consider is that the glue must D R Y , the epoxy just needs to cure. SO, the plywood must not be coated with anything. The foam is impermeable and two sheets must be epoxied together. If you glue it together with TB it will not dry this year or next. JIB

                ---------- Original Message ----------
                From: "prairiedog2332" <nelsarv@...>
                To: Michalak@yahoogroups.com
                Subject: [Michalak] Re: Woobo Revisited
                Date: Mon, 19 Aug 2013 19:05:18 -0000



                Fine Woodworking did some glue tests quite awhile back now and they
                showed regular TB had a higher sheer strength than TBII or III but they
                of course had perfectly fitting clamped joints and no testing about
                joining wood to foam board. I am wondering if a person ran some shallow
                kerfs in the back of the structural foam and then when pressed into
                place against the curved hull sections, the kerfs would open and a glue
                slurry might ooze up to fill them, and make for some nice smooth joints
                with no gaps and the foam board sort of "locked" in place?

                Taking Sam's hull area estimate of 78 sq. ft. and my weight calcs for
                3mm Baltic birch and 1" foam board. Those materials come to about 41
                pounds for a bare hull. Of course that is bare with no framing, decks, 4
                oz glass, epoxy, paints and bed sheets:) I am thinking cedar for frames,
                slotted whales, aluminum tubes for spars, but a heavier transom for
                the motor.

                Sam also asked about SOF but I don't have a lot of faith in them for
                sailing. First to get them stiff enough and second a sailboat doesn't
                have very good brakes if something sharp suddenly appears. I have sailed
                in a Klepper Aerius II rigged to spec with the sloop rig and it was not
                as great as advertised going to weather. Keeping the stays from sagging
                almost impossible, so we ended up accepting a tow. Plus there are a lot
                of sharp rocks in places I might go, plus the SOF's I have seen are not
                that light. Also I had a Folbot that was heavier than my 18' canoe and
                still have a 15' Pakboat. The worst canoes for getting scraped open by
                rocks were the Grumman aluminum lightweights.

                I think JIB's ideas are opening a whole new field of potential design
                options when one takes weight into consideration as we get older and
                feebler. We have some older cowgirls and canoeists around here that are
                really stronger than I and would be great crew. I'll do the cooking if
                they help with the lifting. "Tote that barge, lift that bale." LOL.

                Nels

                --- In Michalak@yahoogroups.com, "jhargrovewright2@..." wrote:
                >
                > Nels, I am considerably weaker as I age sooo weight becomes more than
                just convenience. I have used epoxy for laminating but am experimenting
                with TB-III. It seems to work well. Decks and compartments do add a lot
                of weight and take up room but they both stiffen up the torsional
                rigidity of the boat. That is not so important now with the way we build
                boats today....with an adhesive on each join. Good design requires good
                compromise. The tonneau type cover can work well if constructed
                thoughtfully. I find them difficult to get "right". The weight of the
                two boats seem off, which one? or both. I do not have the plan so can't
                calculate.
                > The fabric/foam/paint works well for me but many or most would not
                like it.....but I get to make the choices, don't I. JIB

                [Non-text portions of this message have been removed]







                [Non-text portions of this message have been removed]
              • prairiedog2332
                JIB, I consider this an invaluable piece of information - thanks for it as your experience saves me having to discover it meself:-) The more I think about it
                Message 7 of 25 , Aug 20, 2013
                  JIB,
                  I consider this an invaluable piece of information - thanks for it as
                  your experience saves me having to discover it meself:-) The more I
                  think about it the more attracted I am to going to a lightweight option
                  even though epoxy is pretty pricey were I am located. Getting the hull
                  "right" is the thing to do and then consider other options for saving
                  weight.

                  Using your method of constructing the hull first with 3mm plywood and
                  THEN installing the foam after must make a pretty loosey goosey hull at
                  first. But the hull of Woobo is sort of like a monoque shape as all
                  major panels are curved except for the bulkheads and decking. Still
                  thinking of installing all the foam first just using weights instead of
                  vacuum- bagging and wonder if the foam will bend enough in the gradual,
                  rather long narrow curves on that hull.

                  Must add I am also attracted to Mixer now as well. I think a slower
                  design under sail but adding the Woobo draining motor well for a small
                  OB and just might end up using the motor more often is all. Certainly it
                  would load into the back of the pick-up more easily. Be even lighter
                  portaging with wheels stored on deck, easier to row, and a smaller
                  lighter sail rig. Only thing one would really have to go minimal
                  backpacking mode especially with two. Solo would be great!

                  What gets me is that waterline length on Woobo. About 14 ft. on a 15 ft.
                  hull and a narrow cross-section at that waterline if kept light. Can`t
                  stop drooling when looking at that!

                  http://www.duckworksbbs.com/ProductDetails.asp?ProductCode=JM-Woobo
                  <http://www.duckworksbbs.com/ProductDetails.asp?ProductCode=JM-Woobo>

                  Yeah! Nels

                  --- In Michalak@yahoogroups.com, "jhargrovewright2@..." wrote:
                  >
                  > Nels, Just make up a small panel let it dry well... then try to tear
                  apart. Plenty of shear strength. I "sand" the foam with very coarse
                  sandpaper before applying the glue....actually just drag it over. I
                  have gone through the kerf, poking holes, knife cuts and see no
                  difference. The important, critical, necessary thing to consider is
                  that the glue must D R Y , the epoxy just needs to cure. SO, the
                  plywood must not be coated with anything. The foam is impermeable and
                  two sheets must be epoxied together. If you glue it together with TB it
                  will not dry this year or next. JIB
                  >




                  [Non-text portions of this message have been removed]
                • jhargrovewright2@juno.com
                  Nels, Woobo and Ladybug are fast and able boats and relatively easy to build. Marvelous both. I never got to sail or even see Chucks (Duckworks) Ladybug.
                  Message 8 of 25 , Aug 20, 2013
                    Nels, Woobo and Ladybug are fast and able boats and relatively easy to build. Marvelous both. I never got to sail or even see Chucks (Duckworks) Ladybug. They both are excellent candidates for the thin ply/foam construction method.
                    Your comment about 3mm hull being loosey goosey is not any more so than thicker ply after it is joined together. 1/2" foam is easily bent in any kind of radius's that ply can bend. No problem. When you get really tight the inside side will start wrinkling before it pops. 3/4 is significantly stiffer but still as bendable as plywood. Again the most difficult quality control is getting 100% of the panel glued. It is not easy!!! It is difficult. JIB
                    ---------- Original Message ----------
                    From: "prairiedog2332" <nelsarv@...>


                    JIB,
                    I consider this an invaluable piece of information - thanks for it as
                    your experience saves me having to discover it meself:-) The more I
                    think about it the more attracted I am to going to a lightweight option
                    even though epoxy is pretty pricey were I am located. Getting the hull
                    "right" is the thing to do and then consider other options for saving
                    weight.

                    Using your method of constructing the hull first with 3mm plywood and
                    THEN installing the foam after must make a pretty loosey goosey hull at
                    first. But the hull of Woobo is sort of like a monoque shape as all
                    major panels are curved except for the bulkheads and decking. Still
                    thinking of installing all the foam first just using weights instead of
                    vacuum- bagging and wonder if the foam will bend enough in the gradual,
                    rather long narrow curves on that hull.

                    Must add I am also attracted to Mixer now as well. I think a slower
                    design under sail but adding the Woobo draining motor well for a small
                    OB and just might end up using the motor more often is all. Certainly it
                    would load into the back of the pick-up more easily. Be even lighter
                    portaging with wheels stored on deck, easier to row, and a smaller
                    lighter sail rig. Only thing one would really have to go minimal
                    backpacking mode especially with two. Solo would be great!

                    What gets me is that waterline length on Woobo. About 14 ft. on a 15 ft.
                    hull and a narrow cross-section at that waterline if kept light. Can`t
                    stop drooling when looking at that!

                    http://www.duckworksbbs.com/ProductDetails.asp?ProductCode=JM-Woobo
                    <http://www.duckworksbbs.com/ProductDetails.asp?ProductCode=JM-Woobo>

                    >

                    [Non-text portions of this message have been removed]







                    [Non-text portions of this message have been removed]
                  • prairiedog2332
                    Just thought I would add a bit of background history on Woobo. A contest sponsored by Woodenboat back in 91 for the perfect skiff . That was for one that
                    Message 9 of 25 , Aug 20, 2013
                      Just thought I would add a bit of background history on Woobo. A
                      contest sponsored by Woodenboat back in '91 for the "perfect skiff".
                      That was for one that would sail, row and motor equally well, and could
                      be camped out in. As Jim says it never won.
                      "The usual result is that the winning boat is the slickest looking boat
                      but not the best functionally. The winning design in this case was quite
                      good but I'd still bet that Woobo is superior functionally in every
                      way." I recall the winner was reviewed after it was built and I agree
                      it was not that impressive.

                      Ironically Bolger entered as well and he called his "The Perfect Skiff"
                      He later renamed it as the "Common Sense Skiff" as the owner of Common
                      Sense designs marketed the plans. An excerpt from A Bolger group post:

                      "Also known as the Common Sense Skiff, design no. 571, it was an entry
                      in the 1991 WB contest. There's an article about it in the 15 Feb
                      1996 issue of MAIB, as well as in an old Bernie Wolfard CSD catalog.

                      It's 15'6" x 4'2" with a gunter sloop rig of 107 sq.ft. There is an
                      off-centreboard and a swing-up rudder. It's also designed to row or
                      use a small outboard. It has a flat, rockered bottom, unflared sides
                      and a smallish bow transom. Wolfard said it would be more complicated
                      to build than other small Bolger instant boats because of its Swiss-
                      army-knife capability."

                      I think the plans are $100 last I saw. Hmm - $22.50 for Jim's version?

                      Nels






                      [Non-text portions of this message have been removed]
                    • Robert
                      Nels, I am going to have to order plans! After checking various charts online it seems 1/4 pine ply weighs roughly 25 pounds. Jim usually quotes finished
                      Message 10 of 25 , Aug 20, 2013
                        Nels,

                        I am going to have to order plans! After checking various charts online it seems 1/4" pine ply weighs roughly 25 pounds. Jim usually quotes finished weight to equal the stack of ply used. In this case Woobo uses 6 sheets of 1/4" hence the 150 pound estimate. I am assuming this includes glass on the bottom?

                        The chart on CLC's website indicates 4 mm okoume (5/32) weighs only 13 pounds. As mentioned lighter glass like 4 ounce could be used. Using the same formula yields a 78 pound boat! It might cost more but careful attention to using light framing lumber, smaller fillets etc would get you a strong, long lasting hull at under 90 pounds. 4mm okoume, BS1088, might be better than typical 5 mm (1/4") big box ply.


                        --- In Michalak@yahoogroups.com, "prairiedog2332" <nelsarv@...> wrote:
                        >
                        > Not letting this thread die out:-)
                        >
                        > I am doing some research online on what may work best for a convertible
                        > shelter topper on a Woobo. At the moment the Enigma design strikes me as
                        > being the best option with perhaps a few mods as seen on other shelter
                        > versions on small hulls. The Enigma version is great as it can be left
                        > open aft and still work as a spray hood and for using a yuloh. Starts
                        > to rain and can be zipped up tight and slept under.
                        >
                        > Rene Vidmer's bimini design can do that too but also serves as a bimini
                        > for sun and bug protection. Bit too tall for this sailboat though. Scott
                        > Widmier made a great innovation on his PDR in the Everglades challenge.
                        > He added a 2nd layer of polytarp to the roof on his shelter top that
                        > prevents condensation under it. Could this be extendable aft over the
                        > rear of the Enigma design to provide sun shade as well with the aft
                        > section open to the breeze? Probably would require an additional
                        > removable bimini frame on the transom. Add some bug protection screens
                        > and can sleep comfortably even in temps too warm for zipping down the
                        > Enigma design. So an adaptable option.
                        >
                        > My other thought is that for me the standard Woobo is just too heavy at
                        > 150 lb. Would prefer to get it down to about 80-90 lbs so that two
                        > people could handle, launch and retrieve in some situations. So am
                        > researching the foam core option over the plans that call for solid 1/4"
                        > plywood.
                        >
                        >
                        > So I wonder if I have to bite the bullet and go for marine grade
                        > plywood on the hull or would 3mm baltic birch suffice if protected by 4
                        > oz glass and graphite on the bottom? $20 a sheet at my retailer.
                        >
                        >
                        > I have some of this foam insulation and it really looks stiff but only
                        > comes in the 1" as least thick. Wondering what I could seal it off with?
                        > I would add a light grating over the living area to take crew weight,
                        > remove some of the foam for a sump and pump out collected water with a
                        > kayak hand pump.
                        >
                        >
                        > http://insulation.owenscorning.ca/builders/products/c-200.aspx
                        > <http://insulation.owenscorning.ca/builders/products/c-200.aspx>
                        >
                        >
                        > As mentioned the Woobo panels could have the foam glued on them while
                        > flat prior to assembly, probably using epoxy. Maybe adding some tapes
                        > where they bend around the bulkheads for added stiffness.
                        >
                        >
                        > May sound totally nuts but a motor canoe with capable sailing
                        > performance, weather tight sleep aboard capability , wheels, and
                        > two-person handling, I bet has never been seen on the rivers, lakes and
                        > canals of this country. Let alone at this financial commitment level.
                        >
                        > Nels
                        >
                        >
                        >
                        >
                        > --- In Michalak@yahoogroups.com, "Robert" wrote:
                        > >
                        > > Not nutty at all Nels. I love Woobo, and struggled deciding between
                        > Woobo and Piccup. I opted for Piccup for ease of cartopping, but Woobo
                        > meets the weight limits of my SUV roof rack, and could be lifted there
                        > with help or a ladder type leverage assistance. Easily handled on land
                        > solo for me. Lillistone's Flint is cartopped at the same 150 lbs.
                        >
                        >
                        >
                        >
                        > [Non-text portions of this message have been removed]
                        >
                      • Robert
                        I replied about using 4 mm okoume, but after reading this post realized you could shave a good bit of weight off by using framing lumber to stiffen the hull
                        Message 11 of 25 , Aug 20, 2013
                          I replied about using 4 mm okoume, but after reading this post realized you could shave a good bit of weight off by using framing lumber to stiffen the hull but replacing the decks and bulkheads with airbags and a fabric spray skirt

                          In the sailing canoe I'm fitting out I am toying with the idea of using closed cell foam sheets glued together, cut and sanded into the shape of the hull instead of airbags. A woman in an inflatable kayak was attacked by an alligator near me in June. I just don't like the idea of deflatable flotation!



                          --- In Michalak@yahoogroups.com, "prairiedog2332" <nelsarv@...> wrote:
                          >
                          > Thanks John, sounds like the way to go. What kind of adhesive do you
                          > use for the laminating? I never thought of bed sheets, but I bet the
                          > cheap ones that are made from polyester would work great. So you have
                          > not only a built-in mattress but bottom sheet as well:-) Not only would
                          > it be warmer than plywood but may drum less in a chop I bet.
                          >
                          > I don't quite understand why the 12' Mixer is only at the 90 lb. mark
                          > and Woobo, 3' longer is 150 lb. - both with identical cross-sections
                          > from the Piccup Pram - only narrowed 6".
                          >
                          > http://www.duckworksbbs.com/ProductDetails.asp?ProductCode=JM-Mixer
                          > <http://www.duckworksbbs.com/ProductDetails.asp?ProductCode=JM-Mixer>
                          >
                          >
                          > Covered decking and hatches really add a lot of weight and might be
                          > shortened if one is carrying waterproof portage packs anyway but then
                          > the top covered shelter would have to made longer. One could add a
                          > fabric "tonneau cover" under which the packs could be stored and
                          > accessed from inside the closed in top or lifted out when portaging.
                          > Things really can get complicated quickly.
                          >
                          >
                          > Nels
                          >
                          >
                          >
                          > --- In Michalak@yahoogroups.com, "jhargrovewright2@" wrote:
                          > >
                          > > Nels, That is the way I build now. 1/8" ply glued to 1/2" or 3/4"
                          > blue foam from Low's. If it really needs more strength several layers.
                          > I use FG tape on the plywood joints inside and out and apply the foam
                          > very carefully fitted, after the hull is built. I use a shop vac to
                          > vacuum bag or a venture vacuum pump to laminate depending on the
                          > arrangement size and difficulty. It is very difficult to get 100% of
                          > the panel laminated without vacuum. The interior surface is cloth
                          > painted on the foam. I use cheap bed sheets. It works and lasts lasts
                          > longer than I would anticipate. It becomes a very stiff sandwich panel
                          > since the cloth is in tension in an impact or water pressure load. The
                          > foam is comfortable to sit and sleep on and is warm in the cold. JIB
                          > > ---------- Original Message ----------
                          > > From: "prairiedog2332" nelsarv@
                          > >
                          > >
                          > >
                          > >
                          > >
                          > > [Non-text portions of this message have been removed]
                          > >
                          >
                          >
                          >
                          > [Non-text portions of this message have been removed]
                          >
                        • prairiedog2332
                          Robert, What you say sounds probably correct and Jim generally figures in 10 oz. glass. Jim doesn t say how many sheets of what thickness Mixer uses so
                          Message 12 of 25 , Aug 21, 2013
                            Robert,

                            What you say sounds probably correct and Jim generally figures in 10
                            oz. glass. Jim doesn't say how many sheets of what thickness Mixer
                            uses so maybe got the weight of 90 lb. from one of the builders.

                            The BS1088 Okoume is really sweet stuff from what I have heard. My yard
                            doesn't bring it in and the shipping is very expensive for a few sheets.
                            But if you can get it, 4mm should work great for Woobo or Mixer. If you
                            think you might need thicker than that for the bottom, you can test it
                            once it is built and inverted by pressing down on the bottom and bilge
                            panels and just use heavier glass on the outside if it seems to flex too
                            much.

                            I have this table for weights of marine plywoods. The 3mm Oko1088 is 8.8
                            lbs a sheet!

                            http://www.noahsmarine.com/itemMatrix.asp?GroupCode=OKO1088&MatrixType=1
                            <http://www.noahsmarine.com/itemMatrix.asp?GroupCode=OKO1088&MatrixType=\
                            1>

                            Nels

                            -- In Michalak@yahoogroups.com, "Robert" wrote:
                            > Nels,
                            >
                            > I am going to have to order plans! After checking various charts
                            online it seems 1/4" pine ply weighs roughly 25 pounds. Jim usually
                            quotes finished weight to equal the stack of ply used. In this case
                            Woobo uses 6 sheets of 1/4" hence the 150 pound estimate. I am assuming
                            this includes glass on the bottom?
                            >
                            > The chart on CLC's website indicates 4 mm okoume (5/32) weighs only 13
                            pounds. As mentioned lighter glass like 4 ounce could be used. Using the
                            same formula yields a 78 pound boat! It might cost more but careful
                            attention to using light framing lumber, smaller fillets etc would get
                            you a strong, long lasting hull at under 90 pounds. 4mm okoume, BS1088,
                            might be better than typical 5 mm (1/4") big box ply.
                            >
                            >
                            > --- In Michalak@yahoogroups.com, "prairiedog2332" nelsarv@ wrote:
                            > >
                            > > Not letting this thread die out:-)
                            > >
                            > > I am doing some research online on what may work best for a
                            convertible
                            > > shelter topper on a Woobo. At the moment the Enigma design strikes
                            me as
                            > > being the best option with perhaps a few mods as seen on other
                            shelter
                            > > versions on small hulls. The Enigma version is great as it can be
                            left
                            > > open aft and still work as a spray hood and for using a yuloh.
                            Starts
                            > > to rain and can be zipped up tight and slept under.
                            > >
                            > > Rene Vidmer's bimini design can do that too but also serves as a
                            bimini
                            > > for sun and bug protection. Bit too tall for this sailboat though.
                            Scott
                            > > Widmier made a great innovation on his PDR in the Everglades
                            challenge.
                            > > He added a 2nd layer of polytarp to the roof on his shelter top that
                            > > prevents condensation under it. Could this be extendable aft over
                            the
                            > > rear of the Enigma design to provide sun shade as well with the aft
                            > > section open to the breeze? Probably would require an additional
                            > > removable bimini frame on the transom. Add some bug protection
                            screens
                            > > and can sleep comfortably even in temps too warm for zipping down
                            the
                            > > Enigma design. So an adaptable option.
                            > >
                            > > My other thought is that for me the standard Woobo is just too heavy
                            at
                            > > 150 lb. Would prefer to get it down to about 80-90 lbs so that two
                            > > people could handle, launch and retrieve in some situations. So am
                            > > researching the foam core option over the plans that call for solid
                            1/4"
                            > > plywood.
                            > >
                            > >
                            > > So I wonder if I have to bite the bullet and go for marine grade
                            > > plywood on the hull or would 3mm baltic birch suffice if protected
                            by 4
                            > > oz glass and graphite on the bottom? $20 a sheet at my retailer.
                            > >
                            > >
                            > > I have some of this foam insulation and it really looks stiff but
                            only
                            > > comes in the 1" as least thick. Wondering what I could seal it off
                            with?
                            > > I would add a light grating over the living area to take crew
                            weight,
                            > > remove some of the foam for a sump and pump out collected water with
                            a
                            > > kayak hand pump.
                            > >
                            > >
                            > > http://insulation.owenscorning.ca/builders/products/c-200.aspx
                            > >
                            > >
                            > >
                            > > As mentioned the Woobo panels could have the foam glued on them
                            while
                            > > flat prior to assembly, probably using epoxy. Maybe adding some
                            tapes
                            > > where they bend around the bulkheads for added stiffness.
                            > >
                            > >
                            > > May sound totally nuts but a motor canoe with capable sailing
                            > > performance, weather tight sleep aboard capability , wheels, and
                            > > two-person handling, I bet has never been seen on the rivers, lakes
                            and
                            > > canals of this country. Let alone at this financial commitment
                            level.
                            > >
                            > > Nels
                            > >
                            > >
                            > >
                            > >
                            > > --- In Michalak@yahoogroups.com, "Robert" wrote:
                            > > >
                            > > > Not nutty at all Nels. I love Woobo, and struggled deciding
                            between
                            > > Woobo and Piccup. I opted for Piccup for ease of cartopping, but
                            Woobo
                            > > meets the weight limits of my SUV roof rack, and could be lifted
                            there
                            > > with help or a ladder type leverage assistance. Easily handled on
                            land
                            > > solo for me. Lillistone's Flint is cartopped at the same 150 lbs.
                            > >
                            > >
                            > >
                            > >
                            > > [Non-text portions of this message have been removed]
                            > >
                            >



                            [Non-text portions of this message have been removed]
                          • daniel brown
                            a woobo built of 3/16 lightweight ply? i dont think of woobo as being a canoe. its a skiff. there arent many canoes with a 4 beam i consider 1/4 ply to be
                            Message 13 of 25 , Aug 21, 2013
                              a woobo built of 3/16" lightweight ply? i dont think of woobo as being a canoe. its a skiff. there arent many canoes with a 4' beam
                              i consider 1/4" ply to be minimal for a 15' skiff



                              To: Michalak@yahoogroups.com
                              From: nelsarv@...
                              Date: Wed, 21 Aug 2013 15:18:27 +0000
                              Subject: [Michalak] Re: Woobo Revisited





                              Robert,

                              What you say sounds probably correct and Jim generally figures in 10
                              oz. glass. Jim doesn't say how many sheets of what thickness Mixer
                              uses so maybe got the weight of 90 lb. from one of the builders.

                              The BS1088 Okoume is really sweet stuff from what I have heard. My yard
                              doesn't bring it in and the shipping is very expensive for a few sheets.
                              But if you can get it, 4mm should work great for Woobo or Mixer. If you
                              think you might need thicker than that for the bottom, you can test it
                              once it is built and inverted by pressing down on the bottom and bilge
                              panels and just use heavier glass on the outside if it seems to flex too
                              much.

                              I have this table for weights of marine plywoods. The 3mm Oko1088 is 8.8
                              lbs a sheet!

                              http://www.noahsmarine.com/itemMatrix.asp?GroupCode=OKO1088&MatrixType=1
                              <http://www.noahsmarine.com/itemMatrix.asp?GroupCode=OKO1088&MatrixType=\
                              1>

                              Nels

                              -- In Michalak@yahoogroups.com, "Robert" wrote:
                              > Nels,
                              >
                              > I am going to have to order plans! After checking various charts
                              online it seems 1/4" pine ply weighs roughly 25 pounds. Jim usually
                              quotes finished weight to equal the stack of ply used. In this case
                              Woobo uses 6 sheets of 1/4" hence the 150 pound estimate. I am assuming
                              this includes glass on the bottom?
                              >
                              > The chart on CLC's website indicates 4 mm okoume (5/32) weighs only 13
                              pounds. As mentioned lighter glass like 4 ounce could be used. Using the
                              same formula yields a 78 pound boat! It might cost more but careful
                              attention to using light framing lumber, smaller fillets etc would get
                              you a strong, long lasting hull at under 90 pounds. 4mm okoume, BS1088,
                              might be better than typical 5 mm (1/4") big box ply.
                              >
                              >
                              > --- In Michalak@yahoogroups.com, "prairiedog2332" nelsarv@ wrote:
                              > >
                              > > Not letting this thread die out:-)
                              > >
                              > > I am doing some research online on what may work best for a
                              convertible
                              > > shelter topper on a Woobo. At the moment the Enigma design strikes
                              me as
                              > > being the best option with perhaps a few mods as seen on other
                              shelter
                              > > versions on small hulls. The Enigma version is great as it can be
                              left
                              > > open aft and still work as a spray hood and for using a yuloh.
                              Starts
                              > > to rain and can be zipped up tight and slept under.
                              > >
                              > > Rene Vidmer's bimini design can do that too but also serves as a
                              bimini
                              > > for sun and bug protection. Bit too tall for this sailboat though.
                              Scott
                              > > Widmier made a great innovation on his PDR in the Everglades
                              challenge.
                              > > He added a 2nd layer of polytarp to the roof on his shelter top that
                              > > prevents condensation under it. Could this be extendable aft over
                              the
                              > > rear of the Enigma design to provide sun shade as well with the aft
                              > > section open to the breeze? Probably would require an additional
                              > > removable bimini frame on the transom. Add some bug protection
                              screens
                              > > and can sleep comfortably even in temps too warm for zipping down
                              the
                              > > Enigma design. So an adaptable option.
                              > >
                              > > My other thought is that for me the standard Woobo is just too heavy
                              at
                              > > 150 lb. Would prefer to get it down to about 80-90 lbs so that two
                              > > people could handle, launch and retrieve in some situations. So am
                              > > researching the foam core option over the plans that call for solid
                              1/4"
                              > > plywood.
                              > >
                              > >
                              > > So I wonder if I have to bite the bullet and go for marine grade
                              > > plywood on the hull or would 3mm baltic birch suffice if protected
                              by 4
                              > > oz glass and graphite on the bottom? $20 a sheet at my retailer.
                              > >
                              > >
                              > > I have some of this foam insulation and it really looks stiff but
                              only
                              > > comes in the 1" as least thick. Wondering what I could seal it off
                              with?
                              > > I would add a light grating over the living area to take crew
                              weight,
                              > > remove some of the foam for a sump and pump out collected water with
                              a
                              > > kayak hand pump.
                              > >
                              > >
                              > > http://insulation.owenscorning.ca/builders/products/c-200.aspx
                              > >
                              > >
                              > >
                              > > As mentioned the Woobo panels could have the foam glued on them
                              while
                              > > flat prior to assembly, probably using epoxy. Maybe adding some
                              tapes
                              > > where they bend around the bulkheads for added stiffness.
                              > >
                              > >
                              > > May sound totally nuts but a motor canoe with capable sailing
                              > > performance, weather tight sleep aboard capability , wheels, and
                              > > two-person handling, I bet has never been seen on the rivers, lakes
                              and
                              > > canals of this country. Let alone at this financial commitment
                              level.
                              > >
                              > > Nels
                              > >
                              > >
                              > >
                              > >
                              > > --- In Michalak@yahoogroups.com, "Robert" wrote:
                              > > >
                              > > > Not nutty at all Nels. I love Woobo, and struggled deciding
                              between
                              > > Woobo and Piccup. I opted for Piccup for ease of cartopping, but
                              Woobo
                              > > meets the weight limits of my SUV roof rack, and could be lifted
                              there
                              > > with help or a ladder type leverage assistance. Easily handled on
                              land
                              > > solo for me. Lillistone's Flint is cartopped at the same 150 lbs.
                              > >
                              > >
                              > >
                              > >
                              > > [Non-text portions of this message have been removed]
                              > >
                              >

                              [Non-text portions of this message have been removed]







                              [Non-text portions of this message have been removed]
                            • prairiedog2332
                              I agree Woobo is a skiff. There have been countless canoes with 4-6 beams built in this country, probably dating back 10,000 years if you include log canoes.
                              Message 14 of 25 , Aug 21, 2013
                                I agree Woobo is a skiff. There have been countless canoes with 4-6 '
                                beams built in this country, probably dating back 10,000 years if you
                                include log canoes. A few weeks ago 23 canoes came down the river here
                                all with beams at least 4 ft. Not sure if this will work from my
                                Facebook page.

                                https://www.facebook.com/photo.php?fbid=10200692030756335&set=a.37237648\
                                45865.2136725.1028169261&type=1&theater
                                <https://www.facebook.com/photo.php?fbid=10200692030756335&set=a.3723764\
                                845865.2136725.1028169261&type=1&theater>

                                You can also Google "Freighter canoes". One photo I saw was of Jim's
                                "Bruceboat"(?) design which is like a longer wider version of Woobo with
                                a flat run aft so it will plane. That is like what most of the freighter
                                canoes had so did not sail except downwind with a jury-rigged square
                                sail. I have seen First Nations people run rapids in big wood and canvas
                                freighter canoes with square sterns and 15-20 hp motors. If it was too
                                shallow for the motor it was raised and both sexes used big long paddles
                                like the early voyagers did, whoopin and singing as they did so. Then
                                when the water got slow they fired up the OB and left us far behind as
                                we only paddled:-)

                                Nels

                                --- In Michalak@yahoogroups.com, daniel brown wrote:
                                >
                                > a woobo built of 3/16" lightweight ply? i dont think of woobo as being
                                a canoe. its a skiff. there arent many canoes with a 4' beam
                                > i consider 1/4" ply to be minimal for a 15' skiff




                                [Non-text portions of this message have been removed]
                              • daniel brown
                                right, canoes can be big. think viking. woobo is a skiff : ) To: Michalak@yahoogroups.com From: nelsarv@hotmail.com Date: Wed, 21 Aug 2013 18:57:58 +0000
                                Message 15 of 25 , Aug 21, 2013
                                  right, canoes can be big. think viking. woobo is a skiff : )






                                  To: Michalak@yahoogroups.com
                                  From: nelsarv@...
                                  Date: Wed, 21 Aug 2013 18:57:58 +0000
                                  Subject: [Michalak] Re: Woobo Revisited





                                  I agree Woobo is a skiff. There have been countless canoes with 4-6 '
                                  beams built in this country, probably dating back 10,000 years if you
                                  include log canoes. A few weeks ago 23 canoes came down the river here
                                  all with beams at least 4 ft. Not sure if this will work from my
                                  Facebook page.

                                  https://www.facebook.com/photo.php?fbid=10200692030756335&set=a.37237648\
                                  45865.2136725.1028169261&type=1&theater
                                  <https://www.facebook.com/photo.php?fbid=10200692030756335&set=a.3723764\
                                  845865.2136725.1028169261&type=1&theater>

                                  You can also Google "Freighter canoes". One photo I saw was of Jim's
                                  "Bruceboat"(?) design which is like a longer wider version of Woobo with
                                  a flat run aft so it will plane. That is like what most of the freighter
                                  canoes had so did not sail except downwind with a jury-rigged square
                                  sail. I have seen First Nations people run rapids in big wood and canvas
                                  freighter canoes with square sterns and 15-20 hp motors. If it was too
                                  shallow for the motor it was raised and both sexes used big long paddles
                                  like the early voyagers did, whoopin and singing as they did so. Then
                                  when the water got slow they fired up the OB and left us far behind as
                                  we only paddled:-)

                                  Nels

                                  --- In Michalak@yahoogroups.com, daniel brown wrote:
                                  >
                                  > a woobo built of 3/16" lightweight ply? i dont think of woobo as being
                                  a canoe. its a skiff. there arent many canoes with a 4' beam
                                  > i consider 1/4" ply to be minimal for a 15' skiff

                                  [Non-text portions of this message have been removed]







                                  [Non-text portions of this message have been removed]
                                • prairiedog2332
                                  Doing some outside renos in my yard right now and it just gets too hot for this Swedish descendant and so have to take a break. And of course the mind wonders
                                  Message 16 of 25 , Aug 21, 2013
                                    Doing some outside renos in my yard right now and it just gets too hot
                                    for this Swedish descendant and so have to take a break. And of course
                                    the mind wonders to boats while I work. Bet JIB can relate:-)

                                    First time I visited the Viking museum in Oslo I was kind of shocked to
                                    see the design of a really ancient one that had a cross-section very
                                    similar to Woobo. Flat bottom and double chines - where I had assumed
                                    they had more rounded hulls - and also had had very vertical stems at
                                    each end - some even re-curved.

                                    The reasoning apparently was when rowed or sailed in light wind only the
                                    bottom was going through the water, thus less whetted area and less
                                    resistance. Once the winds pick up it heels over and the bilge panel
                                    immerses, it stiffens up and the 2nd hard chine offers resistance to
                                    leeway even though it has a very shallow keel and was intended to sail
                                    free, and not pinched going to weather. And of course the plumb stems
                                    give the longest waterline length per overall length.

                                    Granted Woobo looks nothing like a Viking ship but if you look at the
                                    mid-hull cross-section it is almost identical to one. The flat bottom
                                    allows beaching capability. The pointy stern allowed backing off
                                    quickly, to quote Bolger; "...in a hurry if the enterprise ashore
                                    doesn't go well." So we can do without a pointy stern and instead use an
                                    OB if that happens:-)

                                    Canoes, with slacker bilges don't stiffen up like that so will not sail
                                    like that either. And Jim's leeboard and rudder design probably make for
                                    a bit better upwind ability than the Vikings had.

                                    I did also realize that if Woobo gets too light then probably one has to
                                    consider ballast. The Vikings used rocks, so could one do it with
                                    supplies instead - maybe not. But the range of self-righting can be
                                    improved with higher topsides and Chris' thoughts on Robsboat - a hard
                                    shelter extended right out the gunnels. Maybe a removable one if going
                                    out on some larger lakes and having a soft cover that could be rolled
                                    back to have it open on top in good weather. So it would be like an
                                    older sports car. Soft top like Enigma and a hard top option. Both the
                                    late Phil Bolger and the late Don Elliot were doing design work along
                                    that line.

                                    Nels


                                    --- In Michalak@yahoogroups.com, "prairiedog2332" wrote:
                                    >
                                    > I agree Woobo is a skiff.



                                    [Non-text portions of this message have been removed]
                                  • tlclarke1414
                                    What if we used contact cement on the 3mil play and the foam... put down a bunch of thin battens... lay foam on top and pull out the battens... trim the foam
                                    Message 17 of 25 , Aug 21, 2013
                                      What if we used contact cement on the 3mil play and the foam... put down a bunch of thin battens... lay foam on top and pull out the battens... trim the foam as needed...

                                      --- In Michalak@yahoogroups.com, "jhargrovewright2@..." <jhargrovewright2@...> wrote:
                                      >
                                      > Nels, Woobo and Ladybug are fast and able boats and relatively easy to build. Marvelous both. I never got to sail or even see Chucks (Duckworks) Ladybug. They both are excellent candidates for the thin ply/foam construction method.
                                      > Your comment about 3mm hull being loosey goosey is not any more so than thicker ply after it is joined together. 1/2" foam is easily bent in any kind of radius's that ply can bend. No problem. When you get really tight the inside side will start wrinkling before it pops. 3/4 is significantly stiffer but still as bendable as plywood. Again the most difficult quality control is getting 100% of the panel glued. It is not easy!!! It is difficult. JIB
                                      > ---------- Original Message ----------
                                      > From: "prairiedog2332" <nelsarv@...>
                                      >
                                      >
                                      > JIB,
                                      > I consider this an invaluable piece of information - thanks for it as
                                      > your experience saves me having to discover it meself:-) The more I
                                      > think about it the more attracted I am to going to a lightweight option
                                      > even though epoxy is pretty pricey were I am located. Getting the hull
                                      > "right" is the thing to do and then consider other options for saving
                                      > weight.
                                      >
                                      > Using your method of constructing the hull first with 3mm plywood and
                                      > THEN installing the foam after must make a pretty loosey goosey hull at
                                      > first. But the hull of Woobo is sort of like a monoque shape as all
                                      > major panels are curved except for the bulkheads and decking. Still
                                      > thinking of installing all the foam first just using weights instead of
                                      > vacuum- bagging and wonder if the foam will bend enough in the gradual,
                                      > rather long narrow curves on that hull.
                                      >
                                      > Must add I am also attracted to Mixer now as well. I think a slower
                                      > design under sail but adding the Woobo draining motor well for a small
                                      > OB and just might end up using the motor more often is all. Certainly it
                                      > would load into the back of the pick-up more easily. Be even lighter
                                      > portaging with wheels stored on deck, easier to row, and a smaller
                                      > lighter sail rig. Only thing one would really have to go minimal
                                      > backpacking mode especially with two. Solo would be great!
                                      >
                                      > What gets me is that waterline length on Woobo. About 14 ft. on a 15 ft.
                                      > hull and a narrow cross-section at that waterline if kept light. Can`t
                                      > stop drooling when looking at that!
                                      >
                                      > http://www.duckworksbbs.com/ProductDetails.asp?ProductCode=JM-Woobo
                                      > <http://www.duckworksbbs.com/ProductDetails.asp?ProductCode=JM-Woobo>
                                      >
                                      > >
                                      >
                                      > [Non-text portions of this message have been removed]
                                      >
                                      >
                                      >
                                      >
                                      >
                                      >
                                      >
                                      > [Non-text portions of this message have been removed]
                                      >
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