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Re: [Michalak] Re: Cracked mast

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  • Carl
    I broke a wooden mast on an FJ several years ago and repaired it with TBIII in the break and many clamps. It s still holding after much sailing in boisterous
    Message 1 of 19 , Nov 17, 2010
      I broke a wooden mast on an FJ several years ago and repaired it with TBIII in the break and many clamps. It's still holding after much sailing in boisterous conditions..

      ----- Original Message -----
      From: KEN
      To: Michalak@yahoogroups.com
      Sent: Wednesday, November 17, 2010 10:07 AM
      Subject: Re: [Michalak] Re: Cracked mast



      been reading along.. I've always been a fan of type3 wood glue and clamping, to the rough sawn wood, havent had anything come apart yet! (vs epoxy)
      prairiedog, best suggestion Ive seen so far, like 4" tape overlap spiral wrapping.

      I'd run a large 1/4 round router down all the corners, then spiral wrap one way,
      then sand that, spiral wrap the other way and sand, followed by a tighter (more overlap)
      wrap to the bottom 1/3 or 1/2 of it where it has the most leverage against it.

      I'm not any kind of pro with the stuff, but it makes sense to me the bi-directional cloth being spiral wrapped in opposite directions down it would come up being much stronger.
      epoxy being lighter and more flexible than polyester resin, but we're not talking about a whole lot of surface either. poly kept thin oughtta be flexible enough too, acetone isnt fun stuff but it helps polyester grab into wood pretty good. its also good if you grab some resin off the shelf at a store someplace as a thinner (gawd only knows how old the stuff is).

      --- On Wed, 11/17/10, prairiedog2332 <nelsarv@...> wrote:

      From: prairiedog2332 <nelsarv@...>
      Subject: [Michalak] Re: Cracked mast
      To: Michalak@yahoogroups.com
      Date: Wednesday, November 17, 2010, 12:05 PM



      Rob,

      You might enquire with Chuck over at duckworks about glassing the mast.
      I believe he has glassed at least one of his and maybe more. He makes
      masts oout of western red cedar which is not very strong.

      Not sure of the best way to do this. Would you wrap a length of say 4"
      wide strip of glass tape around the mast like a bandage and then epoxy
      it down or what? How far upwards past the crack should one go? Or should
      one overlap the tape over the cracked section and then spiral the tape
      further apart as one goes up to gradually spread the stress on the wood?

      Sort of like taping a hockey stick:-)

      Would the mast have to be sanded down to bare wood first?

      Nels

      --- In Michalak@yahoogroups.com, "Rob Kellock" <creditscorenz@...>
      wrote:
      >
      > I think I might have to use a chisel to rough up both surfaces,
      because I don't own a grinder. I'm assume that I'll need to get rid of
      as much of the existing expoxy as possible, because I doubt that epoxy
      on top of old expoxy will be much good.
      >
      > --- In Michalak@yahoogroups.com, "prairiedog2332" nelsarv@ wrote:
      > >
      > > I agree and was thinking the same thing.
      > >
      > > Peter Lenihan recommends hollowing both glue faces that are going
      to be
      > > epoxyfied and he does that using an angle grinder applied on an
      angle so
      > > it does not affect the outer edges of the joint. Then enough
      thickened
      > > epoxy is applied so that some of it squeezes out after clamping but
      most
      > > is trapped in the hollowed "trough" between the faces.
      > >
      > > You never get a starved joint that way.
      > >
      > > This works best with solid masts though, as well as rubrails,
      outwhales
      > > etc.
      > >
      > > Nels
      >

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





      [Non-text portions of this message have been removed]
    • Andres Espino
      Okay... I need to backup just a bit since I am in construction phase of a mast. What kind of mast does JM use on boats like Picara and so on... are they solid
      Message 2 of 19 , Nov 17, 2010
        Okay... I need to backup just a bit since I am in construction phase of a mast.

        What kind of mast does JM use on boats like Picara and so on... are they solid masts and tapered like Bolger boats?  Or are they hollow constructions?

        I want to add a mizzen mast (a-la-Bolger/Michalak) to my current boat for the weather-vane effect.

        Andrew



        --- On Wed, 11/17/10, Rob Kellock <creditscorenz@...> wrote:

        From: Rob Kellock <creditscorenz@...>
        Subject: [Michalak] Re: Cracked mast
        To: Michalak@yahoogroups.com
        Date: Wednesday, November 17, 2010, 1:39 AM







         









        Philsboat is the only boat I've built and the first thing I did was build my mast using a locally produced epoxy. Didn't like it and shifted to the West System for everything else. I didn't even own clamps back then so I wrapped the mast with packing tape to make the bond. I think the problem might be that the epoxy wasn't good stuff and the timber, being very dry old recycled rimu, didn't absorb it very well.



        --- In Michalak@yahoogroups.com, "Carl" <shnarg@...> wrote:

        >

        > You say it cracked on the glue line and that you were going to reglue and clamp. Could that be the problem? Clamping a close epoxy joint too tightly could create a glue starved joint. Epoxy doesn't like really tight joints...

























        [Non-text portions of this message have been removed]
      • Hajo Smulders
        AFAIK JM doesn t mess with hollow masts. Not worth it on the size of most of his boats or their intended use. I just finished shaping the spars on my mixer2.
        Message 3 of 19 , Nov 17, 2010
          AFAIK JM doesn't mess with hollow masts. Not worth it on the size of most of
          his boats or their intended use.
          I just finished shaping the spars on my mixer2. In his book he describes the
          standard way of rounding spars. I didn't. kept them square. Don't think it's
          gonna make a huge difference at 5 knots. They are tapered. my mast on a
          balanced lug 11'6" mast goes from 2" to 1.5" (Actually mine goes from 2 1/4"
          to 1.5" just easier dealing with three 3/4" planks laminated...)
          For a mizzen I would use a solid tapered squarish mast. When bored next non
          sailing season you can always go for a birdsmouth mast. But on a mizzen the
          advantages would be close to none. It's a fun build though; but do it on the
          main first since the difference will be bigger there.
          I don't think you're going to notice a difference on a picara between square
          or round either. The weight might make a slight difference. Also: having
          build a few boats: get on the water first; you'll tinker with it later
          anyway. And after some tinkering you'll probably build a new boat. And
          that's how it goes ;-) ...

          Hajo
          --
          �A human being should be able to change a diaper, plan an invasion, butcher
          a hog, conn a ship, design a building, write a sonnet, balance accounts,
          build a wall, set a bone, comfort the dying, take orders, give orders,
          cooperate, act alone, solve equations, analyze a new problem, pitch manure,
          program a computer, cook a tasty meal, fight efficiently, die gallantly.
          Specialization is for insects.� (R. Heinlein)


          On Wed, Nov 17, 2010 at 9:52 PM, Andres Espino <
          ima_very_cool_cowboy@...> wrote:

          >
          >
          > Okay... I need to backup just a bit since I am in construction phase of a
          > mast.
          >
          > What kind of mast does JM use on boats like Picara and so on... are they
          > solid masts and tapered like Bolger boats? Or are they hollow
          > constructions?
          >
          > I want to add a mizzen mast (a-la-Bolger/Michalak) to my current boat for
          > the weather-vane effect.
          >
          > Andrew
          >
          > --- On Wed, 11/17/10, Rob Kellock <creditscorenz@...<creditscorenz%40yahoo.com.au>>
          > wrote:
          >
          > From: Rob Kellock <creditscorenz@...<creditscorenz%40yahoo.com.au>
          > >
          > Subject: [Michalak] Re: Cracked mast
          > To: Michalak@yahoogroups.com <Michalak%40yahoogroups.com>
          > Date: Wednesday, November 17, 2010, 1:39 AM
          >
          >
          >
          > Philsboat is the only boat I've built and the first thing I did was build
          > my mast using a locally produced epoxy. Didn't like it and shifted to the
          > West System for everything else. I didn't even own clamps back then so I
          > wrapped the mast with packing tape to make the bond. I think the problem
          > might be that the epoxy wasn't good stuff and the timber, being very dry old
          > recycled rimu, didn't absorb it very well.
          >
          > --- In Michalak@yahoogroups.com <Michalak%40yahoogroups.com>, "Carl"
          > <shnarg@...> wrote:
          >
          > >
          >
          > > You say it cracked on the glue line and that you were going to reglue and
          > clamp. Could that be the problem? Clamping a close epoxy joint too tightly
          > could create a glue starved joint. Epoxy doesn't like really tight joints...
          >
          > [Non-text portions of this message have been removed]
          >
          >
          >


          [Non-text portions of this message have been removed]
        • Joe T
          Lest we forget... Epoxy gluing hints for porous surfaces: ---First get down to clean mating surfaces. Brush both surfaces with straight epoxy and allow it to
          Message 4 of 19 , Nov 17, 2010
            Lest we forget...

            Epoxy gluing hints for porous surfaces: ---First get down to clean mating surfaces. Brush both surfaces with straight epoxy and allow it to soak in. While still wet apply thickened epoxy. Join with enough pressure to get some squeeze out. Cure.
            When in doubt, Reread the manual.

            Works for me every time.

            Joe T
          • Joe T
            ...and one more hint: Lumber and ply could have a hard surface from the milling process. Glue absorption can be improved with a light sanding of mating
            Message 5 of 19 , Nov 17, 2010
              ...and one more hint: Lumber and ply could have a hard surface from the milling process. Glue absorption can be improved with a light sanding of mating surfaces.

              Joe T

              --- In Michalak@yahoogroups.com, "Joe T" <scsbmsjoe@...> wrote:
              >
              > Lest we forget...
              >
              > Epoxy gluing hints for porous surfaces: ---First get down to clean mating surfaces. Brush both surfaces with straight epoxy and allow it to soak in. While still wet apply thickened epoxy. Join with enough pressure to get some squeeze out. Cure.
              > When in doubt, Reread the manual.
              >
              > Works for me every time.
              >
              > Joe T
              >
            • Andres Espino
              THANKS for the input... what is the name of the JM book you are referring to?  I only knew to order specific boat plans. Andrew ... From: Hajo Smulders
              Message 6 of 19 , Nov 18, 2010
                THANKS for the input... what is the name of the JM book you are referring to?  I only knew to order specific boat plans.

                Andrew



                --- On Wed, 11/17/10, Hajo Smulders <hajosmulders@...> wrote:

                From: Hajo Smulders <hajosmulders@...>
                Subject: Re: [Michalak] Re: MASTS
                To: Michalak@yahoogroups.com
                Date: Wednesday, November 17, 2010, 8:13 PM

                AFAIK JM doesn't mess with hollow masts. Not worth it on the size of most of
                his boats or their intended use.
                I just finished shaping the spars on my mixer2. In his book he describes the
                standard way of rounding spars. I didn't. kept them square. Don't think it's
                gonna make a huge difference at 5 knots. They are tapered. my mast on a
                balanced lug 11'6" mast goes from 2" to 1.5" (Actually mine goes from 2 1/4"
                to 1.5" just easier dealing with three 3/4" planks laminated...)
                For a mizzen I would use a solid tapered squarish mast. When bored next non
                sailing season you can always go for a birdsmouth mast. But on a mizzen the
                advantages would be close to none. It's a fun build though; but do it on the
                main first since the difference will be bigger there.
                I don't think you're going to notice a difference on a picara between square
                or round either. The weight might make a slight difference. Also: having
                build a few boats: get on the water first; you'll tinker with it later
                anyway. And after some tinkering you'll probably build a new boat. And
                that's how it goes ;-) ...

                Hajo
                --
                “A human being should be able to change a diaper, plan an invasion, butcher
                a hog, conn a ship, design a building, write a sonnet, balance accounts,
                build a wall, set a bone, comfort the dying, take orders, give orders,
                cooperate, act alone, solve equations, analyze a new problem, pitch manure,
                program a computer, cook a tasty meal, fight efficiently, die gallantly.
                Specialization is for insects.” (R. Heinlein)


                On Wed, Nov 17, 2010 at 9:52 PM, Andres Espino <
                ima_very_cool_cowboy@...> wrote:

                >
                >
                > Okay... I need to backup just a bit since I am in construction phase of a
                > mast.
                >
                > What kind of mast does JM use on boats like Picara and so on... are they
                > solid masts and tapered like Bolger boats?  Or are they hollow
                > constructions?
                >
                > I want to add a mizzen mast (a-la-Bolger/Michalak) to my current boat for
                > the weather-vane effect.
                >
                > Andrew
                >
                > --- On Wed, 11/17/10, Rob Kellock <creditscorenz@...<creditscorenz%40yahoo.com.au>>
                > wrote:
                >
                > From: Rob Kellock <creditscorenz@...<creditscorenz%40yahoo.com.au>
                > >
                > Subject: [Michalak] Re: Cracked mast
                > To: Michalak@yahoogroups.com <Michalak%40yahoogroups.com>
                > Date: Wednesday, November 17, 2010, 1:39 AM
                >
                >
                >
                > Philsboat is the only boat I've built and the first thing I did was build
                > my mast using a locally produced epoxy. Didn't like it and shifted to the
                > West System for everything else. I didn't even own clamps back then so I
                > wrapped the mast with packing tape to make the bond. I think the problem
                > might be that the epoxy wasn't good stuff and the timber, being very dry old
                > recycled rimu, didn't absorb it very well.
                >
                > --- In Michalak@yahoogroups.com <Michalak%40yahoogroups.com>, "Carl"
                > <shnarg@...> wrote:
                >
                > >
                >
                > > You say it cracked on the glue line and that you were going to reglue and
                > clamp. Could that be the problem? Clamping a close epoxy joint too tightly
                > could create a glue starved joint. Epoxy doesn't like really tight joints...
                >
                > [Non-text portions of this message have been removed]
                >

                >


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



                ------------------------------------

                Yahoo! Groups Links








                [Non-text portions of this message have been removed]
              • Hajo Smulders
                Boatbuilding for Beginners (and Beyond): Everything You Need to Know to Build a Sailboat, a Rowboat, a Motorboat, a Canoe, and More!
                Message 7 of 19 , Nov 18, 2010
                  Boatbuilding for Beginners (and Beyond): Everything You Need to Know
                  to Build a Sailboat, a Rowboat, a Motorboat, a Canoe, and More!

                  http://www.amazon.com/Boatbuilding-Beginners-Beyond-Everything-Motorboat/dp/1891369296/ref=sr_1_1?ie=UTF8&qid=1290094677&sr=8-1

                  I recommend this book to every beginning boat builder. Even when
                  you're building a non-Michalak design, this book is really good.

                  Hajo
                  --
                  “A human being should be able to change a diaper, plan an invasion,
                  butcher a hog, conn a ship, design a building, write a sonnet, balance
                  accounts, build a wall, set a bone, comfort the dying, take orders,
                  give orders, cooperate, act alone, solve equations, analyze a new
                  problem, pitch manure, program a computer, cook a tasty meal, fight
                  efficiently, die gallantly. Specialization is for insects.” (R.
                  Heinlein)


                  On Thu, Nov 18, 2010 at 10:27 AM, Andres Espino
                  <ima_very_cool_cowboy@...> wrote:

                  > THANKS for the input... what is the name of the JM book you are referring to?  I only knew to order specific boat plans.
                  >
                  > Andrew
                • Rob Kellock
                  Thanks very much to all of you for your thoughts about repairing my mast. Now it s time to get my tools out and start doing something! Cheers, Rob.
                  Message 8 of 19 , Nov 18, 2010
                    Thanks very much to all of you for your thoughts about repairing my mast. Now it's time to get my tools out and start doing something!

                    Cheers,

                    Rob.
                  • Andres Espino
                    COOL!  Now that I know the name of it, I also found it on the Duckworks page  http://duckworksbbs.com/media.htm I have been using the building with plywood
                    Message 9 of 19 , Nov 18, 2010
                      COOL!  Now that I know the name of it, I also found it on the Duckworks page  http://duckworksbbs.com/media.htm

                      I have been using the building with plywood manual from Glen-L which is good for basic technique and glassing over the wood.

                      Thanks for the book info!  I will get it!

                      Andrew


                      --- On Thu, 11/18/10, Hajo Smulders <hajosmulders@...> wrote:

                      From: Hajo Smulders <hajosmulders@...>
                      Subject: Re: [Michalak] Re: MASTS
                      To: Michalak@yahoogroups.com
                      Date: Thursday, November 18, 2010, 8:39 AM

                      Boatbuilding for Beginners (and Beyond): Everything You Need to Know
                      to Build a Sailboat, a Rowboat, a Motorboat, a Canoe, and More!

                      http://www.amazon.com/Boatbuilding-Beginners-Beyond-Everything-Motorboat/dp/1891369296/ref=sr_1_1?ie=UTF8&qid=1290094677&sr=8-1

                      I recommend this book to every beginning boat builder. Even when
                      you're building a non-Michalak design, this book is really good.

                      Hajo
                      --
                      “A human being should be able to change a diaper, plan an invasion,
                      butcher a hog, conn a ship, design a building, write a sonnet, balance
                      accounts, build a wall, set a bone, comfort the dying, take orders,
                      give orders, cooperate, act alone, solve equations, analyze a new
                      problem, pitch manure, program a computer, cook a tasty meal, fight
                      efficiently, die gallantly. Specialization is for insects.” (R.
                      Heinlein)


                      On Thu, Nov 18, 2010 at 10:27 AM, Andres Espino
                      <ima_very_cool_cowboy@...> wrote:

                      > THANKS for the input... what is the name of the JM book you are referring to?  I only knew to order specific boat plans.
                      >
                      > Andrew


                      ------------------------------------

                      Yahoo! Groups Links








                      [Non-text portions of this message have been removed]
                    • JeffreyM
                      Actually, epoxy sticks to itself very well, provided the surface isn t too smooth. So sand first. I m not sure I have a clear image of this mast break, but
                      Message 10 of 19 , Nov 18, 2010
                        Actually, epoxy sticks to itself very well, provided the surface isn't too smooth. So sand first. I'm not sure I have a clear image of this mast break, but one thing to keep in mind is that all glues, epoxy included, get their strength from the size of the surfaces being glued. That's why joints with small surface area get mechanical fastenings like screws. So this may be a mast design problem and call for more than just epoxy. Fiberglass is good, but is really a bandage in this case: continuous lengths of good lumber is better.
                        Jeff Michals-Brown

                        --- In Michalak@yahoogroups.com, "Joe T" <scsbmsjoe@...> wrote:
                        >
                        > ...and one more hint: Lumber and ply could have a hard surface from the milling process. Glue absorption can be improved with a light sanding of mating surfaces.
                        >
                        > Joe T
                        >
                        > --- In Michalak@yahoogroups.com, "Joe T" <scsbmsjoe@> wrote:
                        > >
                        > > Lest we forget...
                        > >
                        > > Epoxy gluing hints for porous surfaces: ---First get down to clean mating surfaces. Brush both surfaces with straight epoxy and allow it to soak in. While still wet apply thickened epoxy. Join with enough pressure to get some squeeze out. Cure.
                        > > When in doubt, Reread the manual.
                        > >
                        > > Works for me every time.
                        > >
                        > > Joe T
                        > >
                        >
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