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Re: [Cedar Strip Canoes] Re: Another build question

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  • James D. Marco
    Steve, I like my canoes set to run pretty level or a little bow high. So, a light paddler would not hurt the trim of the canoe. Basically, seat placement is
    Message 1 of 18 , Apr 7, 2010
      Steve,
      I like my canoes set to run pretty level or a little bow high. So, a light paddler
      would not hurt the trim of the canoe. Basically, seat placement is more of an art
      than science. Too much weight in the stern can leave you in with an unstable
      boat for solo use. And the windage will be terrible. My Minnesota II is a bit tippy
      and the front is unmanageable as a solo without about 70# of ballast in the bow
      and my pack. Bucket seats are NOT reversible. This is ignoring thwart placement
      as seat back rests.
      Suggest you wet it down before placing the seats. Usually a couple blocks
      of wood and clamp will hold the center thwart/yoke in. With no load, this will let
      you position each paddler where you need them to be. (I guess I am a bit lucky
      in that regard, I have a 150 yard pond about 3 minutes portage from my little
      barn to test that stuff.) Kneeling should let you center the loads on the canoe.
      Measure both sides at each end and do a quick average...subtract this from the
      depth to get the waterline. Pretty easy. I allow about a half inch bow rise and
      place my seats accordingly. You can place them both closer to center to give
      you a better solo boat (with some ballast.) Or, Do as Tim suggests, place the
      rear seat all the way back (till you are comfortable,) then have Penny move
      forward till the boat trims. This will require a lot of ballast for solo, unless you
      kneel in the center. For a few pounds, you can add a third seat, too.
      As I remember, you had changed the bow a little...this may or may not
      have effected the factory seat recommendations, soo they will be off a bit. Same
      for the yoke.
      Use epoxy for splicing. Even Titebond II will soften with moisture. The
      diagonal should be seen from the top, as Tim was saying. I don't think it really
      matters, though. This is how I have always seen them. Make sure your grain
      runs to the outside on the feather edge. Easier to plane smooth on the outside,
      that way. Clamp it firm, but not too tight. Epoxy will want to slip.
      Gunnels are easy if you have extra length. Yes, they do require a lot of
      clamps. I use spring clamps every 1" or so, soo, I guess on a 14' boat I would use
      about 50 or so. Probably a couple screw type to get you started. The dual curve
      can be a bear and requires some extra effort compared to stripping the hull. It
      is a long thin piece and should form easily, though. A few screw clamps will be
      needed, at any rate. At the bow and stern, you may need two longer screws going
      through the gunnel, hull, deck plate and gunnel. I use 3" coated deck screws and
      2-1/2" coated screws at each stem. Start at one end, alternate sides. Measure
      widths, as you go. A little stress can induce a bulge. Play with the clamps a bit,
      and, pull or tap the end. It will change the width about 1/32. A little fussing will be
      needed, but worth it.
      Most people put the decks in backwards. The stress is outwards on the
      gunnel. Soo, the grain should run along the hand grip. Make sure they are drilled
      properly, it could split the wood. Do not go through the same grain line with both
      screws. The rest kind'a just lays. I use a little dovetail on the inner gunnel, but this
      is probably not necessary, I like to see it locked.
      Butternut is nice, better than cedar, spruce or Doug fir for durability by far.
      And it has good rot resistance. If you don't want it ,send it to me...I'll find a use for
      it somewhere....;-)
      My thoughts only . . .
      jdm






      At 06:48 PM 4/6/2010, you wrote:
      >Tim,
      >
      >Thanks.
      >
      >I originally bought the butternut wood to make a furniture grade tack trunk for Penny. It's become a coffee table in the family room. I bought enough for two trunks but never built the second one. I've been around and around with this gunwale material issue. I initially found a piece of mahagony, barely wide enough but 18' feet long. When I got it home and ripped it to width I rejected it. Although it was clear it had grain issues in a couple of places. I was going to use black walnut(I have it in short lengths), then cherry (I have it in short lengths), then red oak (I have it in short lengths)and then butternut which I milled last night. Looking back I should have gone to my local hardwood supplier, picked up some nice 12' lengths of clear, milled ash, and been done with it. It's kind of frustrating but I'm learning a lot about trimming a cedar strip canoe.
      >
      >I like you assessment of seat location. I'm going to borrow your seat location logic for my HC. As for a sliding seat my Prism has a sliding bucket seat. I like the bucket seat design but in the HC who knows what seat and in what direction I'll be sitting in?
      >
      >Anyway, thanks for the advise.
      >
      >Newbie Steve
      >
      >--- In cedarstripcanoes@yahoogroups.com, "Tim" <casey51234@...> wrote:
      >>
      >> Steve-
      >>
      >> As far as seat placement & type, I am of the school for putting them as close to the ends as is comfortable. The bow seat determined by whether or not you are putting in a flotation chamber, but place it so a tall person (you) can stretch out completely but not any further back. The stern seat where the hull is wide enough for your torso and just a little clearance. This way the hull is narrower where you paddle, and you don't have to shift your weight sideways as far when switching paddle sides, and sweep strokes are more effective. As far as a sliding bow seat, IMO they are a nearly useless complication. If the bow paddler is a little lighter than the stern (usual state- Penny) you can't slide them clear up to the front deck to trim anyway, you ballast for trim- dog, rocks, heavy gear up front. If they're a lot lighter (like a 10 yr old nephew) the best advice I've heard is to turn the boat around "solo" style and have them sit in the stern seat backwards while you sit !
      b!
      > ackwards on the bow seat.
      >>
      >> The gunwale splice should be oriented to give the most surface area, usually see the diagonal from above. I don't know about Butternut for wales...it is light but not very strong or impact resistant. It carves well, would be an excellent choice for decks with decorative carvings. If you are having a hard time bending it in construction, it is going to be weak in use also. I would stick with epoxy on the scarf, you're not using much and it's a critical joint. You could cover the Butternut wales with 2 oz cloth & epoxy to beef them up.
      >>
      >> Tim Greiner
      >>
      >> --- Steve wrote:
      >> >
      >> > Corky, I haven't referred back to the plans to see where the seats are to be located. I'm guessing the plans do specify where the seats are to be located. The instructions that BMB sends with the plans are actually for another much smaller hull. They want you to apply the techniques to whichever of the BMB plans you happen to be building.
      >> >
      >> > After the responses I got about my choice to use red oak and about the suitibility of butternut I inspected my butternut stock and found enough straight-grained stock to make both the inwales and outwales. I planed and ripped enough 3/4" x 7/8" x 8' and made a scarf taper (7 to 1 angle)jig for my table saw. Each gunwale piece will have two scarf splices. My new question is: How should I orient the splice for maximum strength? Should the angled (7:1) seam of the scarf joint be located on the top face or the vertical face of the gunwales?
      >> >
      >> > Next question: An 8' piece of gunwale stock seems too unflexible to easily take the shape of the hull. Has anyone had problems getting the gunwale stock to bend around the hull?
      >> >
      >> > Last question: Is there a problem using Titebond II glue in the scarf joint in stead of epoxy?
      >> >
      >> > Thanks.
      >> >
      >> > Newbie Steve
      >> > --- Corky wrote:
      >> > >
      >> > > Hi Steve, do the plans not tell you where the seats and thwarts should be
      >> > > located? One way to plan for various weight bow paddlers is to install a
      >> > > movable front seat. Then, not only can you adjust for the bow paddler's
      >> > > weight, you can also make adjustments while you are out to counter wind
      >> > > conditions.
      >> > >
      >> > >
      >> > >
      >> > > Corky Scott
      >> > >
      >> > >
      >> >
      >>
      >
      >
      >
      >
      >------------------------------------
      >
      >Yahoo! Groups Links
      >
      >
      >
      James Marco, Computer Operations Manager & Desktop Support
      Chemical and Biomolecular Engineering, and, Biomedical Engineering Departments
      B59 Olin Hall, Cornell University
      Ithaca, NY 14853 Office Phone: 607-255-7312


      [Non-text portions of this message have been removed]
    • Charles & Dana Scott
      Regarding the first question below, if the thwarts and seat frames are the specified length, then the hull will (should) take the shape the designers planned.
      Message 2 of 18 , Apr 7, 2010
        Regarding the first question below, if the thwarts and seat frames are the
        specified length, then the hull will (should) take the shape the designers
        planned. Like I said previously, the hull at the waterline will remain
        pretty much the same regardless whether the hull width at the center thwart
        is slightly larger or smaller than specified. In my opinion.



        As to the glue, within the past year I read a test of glues in one of my
        woodwork magazines. The editors tested a number of glues including the
        typical water soluble carpenters glue like Tightbond, an epoxy glue, a
        gorilla glue type and at least several others. They used the glue to bond
        blocks of wood together, waited till all the glues had properly bonded, and
        then tested the pieces by destroying them using a press that read out the
        pressure required to bust the pieces apart. Notes were made as to whether
        the joint failed at the glue line or if the glue held and the wood split
        elsewhere.



        Guess which glue won the prize as the strongest glue? Surprisingly, to me
        anyway, the water soluble carpenters glue not only beat out all the
        competitors, it was cheaper by far than any other. Plus, it cleans up with
        water.



        Corky Scott



        _____

        From: cedarstripcanoes@yahoogroups.com
        [mailto:cedarstripcanoes@yahoogroups.com] On Behalf Of drippy70
        Sent: Tuesday, April 06, 2010 3:33 PM
        To: cedarstripcanoes@yahoogroups.com
        Subject: Re: [Cedar Strip Canoes] Another build question





        Next question: An 8' piece of gunwale stock seems too unflexible to easily
        take the shape of the hull. Has anyone had problems getting the gunwale
        stock to bend around the hull?

        Last question: Is there a problem using Titebond II glue in the scarf joint
        in stead of epoxy?

        Thanks.

        Newbie Steve



        [Non-text portions of this message have been removed]
      • galeria
        Agree with both points. Changing the yoke length by 1 to 3 inches won´t change much the width at waterline, but it may change the shape of bottom (more or
        Message 3 of 18 , Apr 7, 2010
          Agree with both points. Changing the yoke length by 1 to 3 inches won´t change much the width at waterline, but it may change the shape of bottom (more or less rocker). When you let the hull close on top (smaller yoke), the ends of the canoe will move down (less rocker), but it may get to a point where you have a "negative rocker" at bow and stern, changing the hull performance by a great margin. Just check it by forcing the hull at middle point before you install the yoke thwart.

          On the glue subject, I used to hear that the weak point is usually not on the glue, but the wood itself right beside the glued joint. Most failures occur because the wood surface will fracture at the joint. The tests should include an "after imersion" variable too, although imersion is not really expected after the glass/epoxy lamination... :)

          I use water based glue on all my canoes and some are over 15 years old and holding quite well.... :) Enough epoxy on the outside!!! :)

          TonyBR, from Brazil



          ----- Original Message -----
          From: Charles & Dana Scott
          To: cedarstripcanoes@yahoogroups.com
          Sent: Wednesday, April 07, 2010 10:20 AM
          Subject: RE: [Cedar Strip Canoes] Another build question



          Regarding the first question below, if the thwarts and seat frames are the
          specified length, then the hull will (should) take the shape the designers
          planned. Like I said previously, the hull at the waterline will remain
          pretty much the same regardless whether the hull width at the center thwart
          is slightly larger or smaller than specified. In my opinion.

          As to the glue, within the past year I read a test of glues in one of my
          woodwork magazines. The editors tested a number of glues including the
          typical water soluble carpenters glue like Tightbond, an epoxy glue, a
          gorilla glue type and at least several others. They used the glue to bond
          blocks of wood together, waited till all the glues had properly bonded, and
          then tested the pieces by destroying them using a press that read out the
          pressure required to bust the pieces apart. Notes were made as to whether
          the joint failed at the glue line or if the glue held and the wood split
          elsewhere.

          Guess which glue won the prize as the strongest glue? Surprisingly, to me
          anyway, the water soluble carpenters glue not only beat out all the
          competitors, it was cheaper by far than any other. Plus, it cleans up with
          water.

          Corky Scott

          _____

          From: cedarstripcanoes@yahoogroups.com
          [mailto:cedarstripcanoes@yahoogroups.com] On Behalf Of drippy70
          Sent: Tuesday, April 06, 2010 3:33 PM
          To: cedarstripcanoes@yahoogroups.com
          Subject: Re: [Cedar Strip Canoes] Another build question

          Next question: An 8' piece of gunwale stock seems too unflexible to easily
          take the shape of the hull. Has anyone had problems getting the gunwale
          stock to bend around the hull?

          Last question: Is there a problem using Titebond II glue in the scarf joint
          in stead of epoxy?

          Thanks.

          Newbie Steve

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






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        • Carel Ruysink
          I completely agree with Tim but have a few things to add if you dont mind. If you are not too familiar with canoebuilding and canoeing it is best to have the
          Message 4 of 18 , Apr 7, 2010
            I completely agree with Tim but have a few things to add if you dont mind.
            If you are not too familiar with canoebuilding and canoeing it is best to have the seats where the designer planned them. Only if you are in a not normal situation or have your own specific reasons (from experience) you would like to have the seats in another place.

            You can place the seats as close to the ends as is comfortable for different reasons.
            - The canoe tracks better.
            - Less prone to windeffects.
            - Less influence on tracking from the waves
            - Have the most room for your luggage (one big pile)

            With the seats close to the middle.
            - Boat reacts faster ( most of the mass close to the center of bouyancy)
            - Can handle bigger waves, she "dances"over the waves (less inertia at the ends).
            - More cosy to be close to one another.

            There is hardly/no need to have adjustable seats. I have designed an built my favorite canoe with adjustable seats but I have in all those years never placed the seats in another position. If I paddle her solo I have campinggear to trim her and when empty I use a box/saddle to kneel somewhere at 2/3 from the bow (loose at the bottom).

            And as for switching sides to paddle; the more experienced you become the less you will switch sides. For many years now I never switch sides anymore. I allways paddle at the starboardside. Only in our C10 I paddle at the bow at port because the skipper steers at starboard.
            Anything you want your canoe to do you can do it from one and the same side trough the years you can pick up a lot of tricks.
            It is a thing of beauty to see Marc Ornstein perform some beautyfull maneouvres at youtube like the Omerstroke, sideways etc. that is freestyle at its best and for everyone usefull too ( I only see no direct use in tilting the canoe and paddle over the high side, still even that is funny)

            In short I would say leave it as designed unless you know what you want and know what you are doing.

            Succes, Carel.

            ----- Original Message -----
            From: Tim
            To: cedarstripcanoes@yahoogroups.com
            Sent: Tuesday, April 06, 2010 11:49 PM
            Subject: [Cedar Strip Canoes] Re: Another build question



            Steve-

            As far as seat placement & type, I am of the school for putting them as close to the ends as is comfortable. The bow seat determined by whether or not you are putting in a flotation chamber, but place it so a tall person (you) can stretch out completely but not any further back. The stern seat where the hull is wide enough for your torso and just a little clearance. This way the hull is narrower where you paddle, and you don't have to shift your weight sideways as far when switching paddle sides, and sweep strokes are more effective. As far as a sliding bow seat, IMO they are a nearly useless complication. If the bow paddler is a little lighter than the stern (usual state- Penny) you can't slide them clear up to the front deck to trim anyway, you ballast for trim- dog, rocks, heavy gear up front. If they're a lot lighter (like a 10 yr old nephew) the best advice I've heard is to turn the boat around "solo" style and have them sit in the stern seat backwards while you sit backwards on the bow seat.

            The gunwale splice should be oriented to give the most surface area, usually see the diagonal from above. I don't know about Butternut for wales...it is light but not very strong or impact resistant. It carves well, would be an excellent choice for decks with decorative carvings. If you are having a hard time bending it in construction, it is going to be weak in use also. I would stick with epoxy on the scarf, you're not using much and it's a critical joint. You could cover the Butternut wales with 2 oz cloth & epoxy to beef them up.

            Tim Greiner





            [Non-text portions of this message have been removed]
          • Tim
            Corky- Is this the test you are speaking of? http://www.titebond.com/Download/pdf/HowStrongisYourGlue_FWW.pdf I wish they would have put more details in the
            Message 5 of 18 , Apr 7, 2010
              Corky-

              Is this the test you are speaking of?

              http://www.titebond.com/Download/pdf/HowStrongisYourGlue_FWW.pdf

              I wish they would have put more details in the results. It also isn't aimed at boatbuilders so waterproofing wasn't factored. I think Titebond III is supposed to be completely waterproof, altho I & II weren't. Gorilla sure is a waste of money. Like to see a test of some of the construction adhesives, too, like PL Premium & Liquid Nails.

              Titebond II or III would be OK for the splice, if the II could be guaranteed to be protected from water. They seemed to hint that it is as good as epoxy for gap-filling, contrary to convention. Once again, not providing enough test details makes it harder to get the real lessons.

              Tim Greiner

              --- Corky wrote:
              >
              > Regarding the first question below, if the thwarts and seat frames are the
              > specified length, then the hull will (should) take the shape the designers
              > planned. Like I said previously, the hull at the waterline will remain
              > pretty much the same regardless whether the hull width at the center thwart
              > is slightly larger or smaller than specified. In my opinion.
              >
              >
              >
              > As to the glue, within the past year I read a test of glues in one of my
              > woodwork magazines. The editors tested a number of glues including the
              > typical water soluble carpenters glue like Tightbond, an epoxy glue, a
              > gorilla glue type and at least several others. They used the glue to bond
              > blocks of wood together, waited till all the glues had properly bonded, and
              > then tested the pieces by destroying them using a press that read out the
              > pressure required to bust the pieces apart. Notes were made as to whether
              > the joint failed at the glue line or if the glue held and the wood split
              > elsewhere.
              >
              >
              >
              > Guess which glue won the prize as the strongest glue? Surprisingly, to me
              > anyway, the water soluble carpenters glue not only beat out all the
              > competitors, it was cheaper by far than any other. Plus, it cleans up with
              > water.
              >
              >
              >
              > Corky Scott
              >
              >
              > Subject: Re: [Cedar Strip Canoes] Another build question
              >
              > Next question: An 8' piece of gunwale stock seems too unflexible to easily
              > take the shape of the hull. Has anyone had problems getting the gunwale
              > stock to bend around the hull?
              >
              > Last question: Is there a problem using Titebond II glue in the scarf joint
              > in stead of epoxy?
              >
              > Thanks.
              >
              > Newbie Steve
              >
              >
            • James D. Marco
              Corky, Yeah I agree with that. But, I believe Newbie Steve changed the hull design slightly when he changed the stem and first station. It may not matter, but
              Message 6 of 18 , Apr 7, 2010
                Corky,
                Yeah I agree with that. But, I believe Newbie Steve changed the hull
                design slightly when he changed the stem and first station. It may not matter,
                but at a three thousand mile distance, I cannot say for sure. And it will change
                the rocker, as Galeria was saying. Thwarts, yoke and gunnels need to be computed
                together. Soo, if he is changing the inner gunwale, then that too will effect things.
                I often hang my seats, so their width is secondary, but cleated seats will effect the
                waterline width a small fraction, also. Likely this is all very minor.
                As far as using white glue, I have seen similar tests. No one takes into
                account soaking in the sun for a few hours(getting good and warm), though.
                My thoughts only . . .
                jdm


                At 09:20 AM 4/7/2010, you wrote:
                >Regarding the first question below, if the thwarts and seat frames are the
                >specified length, then the hull will (should) take the shape the designers
                >planned. Like I said previously, the hull at the waterline will remain
                >pretty much the same regardless whether the hull width at the center thwart
                >is slightly larger or smaller than specified. In my opinion.
                >
                >
                >
                >As to the glue, within the past year I read a test of glues in one of my
                >woodwork magazines. The editors tested a number of glues including the
                >typical water soluble carpenters glue like Tightbond, an epoxy glue, a
                >gorilla glue type and at least several others. They used the glue to bond
                >blocks of wood together, waited till all the glues had properly bonded, and
                >then tested the pieces by destroying them using a press that read out the
                >pressure required to bust the pieces apart. Notes were made as to whether
                >the joint failed at the glue line or if the glue held and the wood split
                >elsewhere.
                >
                >
                >
                >Guess which glue won the prize as the strongest glue? Surprisingly, to me
                >anyway, the water soluble carpenters glue not only beat out all the
                >competitors, it was cheaper by far than any other. Plus, it cleans up with
                >water.
                >
                >
                >
                >Corky Scott
              • Anthony Spezio
                Corky, I still use this to glue up some of my Bamboo fly rods I make. It sets quick so I do have to work fast to glue up six splines. But here is the kicker. I
                Message 7 of 18 , Apr 7, 2010
                  Corky,
                  I still use this to glue up some of my Bamboo fly rods I make. It sets quick so I do have to work fast to glue up six splines. But here is the kicker. I glued up a sample section and soaked it in water for a week, It de-laminated. My first rod is glued up with it and it has gotten a lot of use for 11 years, it is still solid as a rock. It gets wet but not soaked for long periods of time.
                  Just passing this on.
                  Arkansas Tony




                  Guess which glue won the prize as the strongest glue? Surprisingly, to me

                  anyway, the water soluble carpenters glue not only beat out all the

                  competitors, it was cheaper by far than any other. Plus, it cleans up with

                  water.



                  Corky Scott<br>


                  _____



                  From: cedarstripcanoes@ yahoogroups. com

                  [mailto:cedarstripcanoes@ yahoogroups. com] On Behalf Of drippy70

                  Sent: Tuesday, April 06, 2010 3:33 PM

                  To: cedarstripcanoes@ yahoogroups. com

                  Subject: Re: [Cedar Strip Canoes] Another build question



                  Next question: An 8' piece of gunwale stock seems too unflexible to easily

                  take the shape of the hull. Has anyone had problems getting the gunwale

                  stock to bend around the hull?



                  Last question: Is there a problem using Titebond II glue in the scarf joint

                  in stead of epoxy?



                  Thanks.



                  Newbie Steve



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

























                  [Non-text portions of this message have been removed]
                • Charles & Dana Scott
                  That sure looks like it. Yes, Titebond III is sold as a waterproof glue. The only thing I d comment on regarding the use of epoxy for gluing pieces as opposed
                  Message 8 of 18 , Apr 7, 2010
                    That sure looks like it. Yes, Titebond III is sold as a waterproof glue.



                    The only thing I'd comment on regarding the use of epoxy for gluing pieces
                    as opposed to using PVA type glue (carpenters glue) is that you can mix a
                    thickener with the epoxy, which makes it a great gap filler. Also, epoxy
                    has a longer pot life. When gluing gunwales to the sides of the hull, a
                    long pot life is extremely helpful.



                    Corky Scott



                    _____

                    From: cedarstripcanoes@yahoogroups.com
                    [mailto:cedarstripcanoes@yahoogroups.com] On Behalf Of Tim
                    Sent: Wednesday, April 07, 2010 10:24 AM
                    To: cedarstripcanoes@yahoogroups.com
                    Subject: [Cedar Strip Canoes] Re: Another build question





                    Corky-

                    Is this the test you are speaking of?

                    http://www.titebond
                    <http://www.titebond.com/Download/pdf/HowStrongisYourGlue_FWW.pdf>
                    .com/Download/pdf/HowStrongisYourGlue_FWW.pdf

                    I wish they would have put more details in the results. It also isn't aimed
                    at boatbuilders so waterproofing wasn't factored. I think Titebond III is
                    supposed to be completely waterproof, altho I & II weren't. Gorilla sure is
                    a waste of money. Like to see a test of some of the construction adhesives,
                    too, like PL Premium & Liquid Nails.

                    Titebond II or III would be OK for the splice, if the II could be guaranteed
                    to be protected from water. They seemed to hint that it is as good as epoxy
                    for gap-filling, contrary to convention. Once again, not providing enough
                    test details makes it harder to get the real lessons.

                    Tim Greiner
                    _



                    [Non-text portions of this message have been removed]
                  • naicrafts
                    It has been my experience that Titebond III is not waterproof. It is very water resistance but when exposed to warm water it will soften and allow the joint to
                    Message 9 of 18 , Apr 9, 2010
                      It has been my experience that Titebond III is not waterproof. It is very water resistance but when exposed to warm water it will soften and allow the joint to separate. This can be a good thing, I had to remove some strips during construction and was able to remove them using water and a hair dryer. After a few minutes the glue softened and the strip could be removed.

                      For gluing joints which will be exposed to water I will only use epoxy with a filler. Scarf joints on a gunwale is a great place for any epoxy joint. From my research a good scarf joint should have a slope of 8:1 to get good surface area. I've seen some post recommend 45 degree (1:1) slopes and don't see how there is enough surface to get good strength.

                      --- In cedarstripcanoes@yahoogroups.com, "Charles & Dana Scott" <charles.k.scott@...> wrote:
                      >
                      > That sure looks like it. Yes, Titebond III is sold as a waterproof glue.
                      >
                      >
                      >
                      > The only thing I'd comment on regarding the use of epoxy for gluing pieces
                      > as opposed to using PVA type glue (carpenters glue) is that you can mix a
                      > thickener with the epoxy, which makes it a great gap filler. Also, epoxy
                      > has a longer pot life. When gluing gunwales to the sides of the hull, a
                      > long pot life is extremely helpful.
                      >
                      >
                      >
                      > Corky Scott
                      >
                      >
                      >
                      > _____
                      >
                      > From: cedarstripcanoes@yahoogroups.com
                      > [mailto:cedarstripcanoes@yahoogroups.com] On Behalf Of Tim
                      > Sent: Wednesday, April 07, 2010 10:24 AM
                      > To: cedarstripcanoes@yahoogroups.com
                      > Subject: [Cedar Strip Canoes] Re: Another build question
                      >
                      >
                      >
                      >
                      >
                      > Corky-
                      >
                      > Is this the test you are speaking of?
                      >
                      > http://www.titebond
                      > <http://www.titebond.com/Download/pdf/HowStrongisYourGlue_FWW.pdf>
                      > .com/Download/pdf/HowStrongisYourGlue_FWW.pdf
                      >
                      > I wish they would have put more details in the results. It also isn't aimed
                      > at boatbuilders so waterproofing wasn't factored. I think Titebond III is
                      > supposed to be completely waterproof, altho I & II weren't. Gorilla sure is
                      > a waste of money. Like to see a test of some of the construction adhesives,
                      > too, like PL Premium & Liquid Nails.
                      >
                      > Titebond II or III would be OK for the splice, if the II could be guaranteed
                      > to be protected from water. They seemed to hint that it is as good as epoxy
                      > for gap-filling, contrary to convention. Once again, not providing enough
                      > test details makes it harder to get the real lessons.
                      >
                      > Tim Greiner
                      > _
                      >
                      >
                      >
                      > [Non-text portions of this message have been removed]
                      >
                    • James D. Marco
                      Mike, Yeah, I pretty much agree, even though it is not as strong as other glues. Even with a thickener, epoxy doesn t loose strength, though. Your observations
                      Message 10 of 18 , Apr 9, 2010
                        Mike,
                        Yeah, I pretty much agree, even though it is not as strong as other glues.
                        Even with a thickener, epoxy doesn't loose strength, though. Your observations
                        pretty much agree with mine. I have a couple old pieces of laminates I did with
                        titebond II. Never tried the titebond III. The 3 year old laminates all broke apart
                        quite easily at the joints after a year of being outside. But, it is not billed as an
                        outside glue, soo, it works well for what it is. At least the table top is still intact.
                        Anyway, the mitered joints were a surprise to me, too. They were quite
                        strong. I did a couple dog "coffins" for the ashes and blocked the joints as
                        is usual. Shortly after, I read in Woodworkers Journal that they tested various
                        joints and the miter did almost as well as a finger joint. But, they hesitated to
                        recommend it due to expansion and contraction issues, even though it tested
                        pretty well. This would be a 1:1 scarf.
                        Depending on the wood you are using, the scarf angle is not absolute.
                        Some of the really oily woods, like rosewood, require a really long angle, 10:1.
                        Even this is a bit weak, because, the glues do not like to bond to rosewood.
                        Pine and softer woods like the firs, you can get away with 5:1 or even 4:1. Some
                        of the japanese framing joints do not use glue at all, simply keys locking them
                        in place. Never tried those, though. I am sure there is some loss of strength.
                        Anyway, the rule of thumb is 7 or 8 to 1. Lots'a debate, soo, I do not think it really
                        matters. For butternut, I would go with 7:1. This is a non oily wood that takes a
                        good glue bond. As always, a matter of choice....going a bit longer will certainly
                        not hurt it.
                        My thoughts only . . .
                        jdm
                        At 11:04 AM 4/9/2010, you wrote:

                        >It has been my experience that Titebond III is not waterproof. It is very water resistance but when exposed to warm water it will soften and allow the joint to separate. This can be a good thing, I had to remove some strips during construction and was able to remove them using water and a hair dryer. After a few minutes the glue softened and the strip could be removed.
                        >
                        >For gluing joints which will be exposed to water I will only use epoxy with a filler. Scarf joints on a gunwale is a great place for any epoxy joint. From my research a good scarf joint should have a slope of 8:1 to get good surface area. I've seen some post recommend 45 degree (1:1) slopes and don't see how there is enough surface to get good strength.
                        >
                        >--- In cedarstripcanoes@yahoogroups.com, "Charles & Dana Scott" <charles.k.scott@...> wrote:
                        >>
                        >> That sure looks like it. Yes, Titebond III is sold as a waterproof glue.
                        >>
                        >>
                        >>
                        >> The only thing I'd comment on regarding the use of epoxy for gluing pieces
                        >> as opposed to using PVA type glue (carpenters glue) is that you can mix a
                        >> thickener with the epoxy, which makes it a great gap filler. Also, epoxy
                        >> has a longer pot life. When gluing gunwales to the sides of the hull, a
                        >> long pot life is extremely helpful.
                        >>
                        >>
                        >>
                        >> Corky Scott
                      • James D. Marco
                        I got thinking about the scarf joints a bit. Soo, I went out to the shop and laid one out. My usual layout is by eye, so, I measured it when I was done. Looks
                        Message 11 of 18 , Apr 11, 2010
                          I got thinking about the scarf joints a bit. Soo, I went out to the shop and
                          laid one out. My usual layout is by eye, so, I measured it when I was done.
                          Looks like about 8.3:1 angle or measured about 11-1/8" long over 3/4"
                          thickness. This is about the best I can manage with a hand plane, without
                          worrying about feather rise at the end. (Likely a little less after cleaning the
                          two pieces to match.)
                          This looks a bit better than 7:1, as I said. So, I am changing to the 8:1
                          angle. The angle, often used for strength in boat building, also has a lot of
                          variations. I googled it this mornng, but came up with a lot of odd joints.
                          Many only apply about 50% of the structural strength of the wood (a half lap
                          for example, was listed as a type of scarf, a bit odd. Others I do not think of
                          as scarfs, like the really common finish miter was listed first.) Again, longer
                          is always better... especially with glues.
                          My apologies for my mistake.
                          jdm
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