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Natural alternatives to Fibreglass cloth?

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  • Marius Lubbe - Creative MindsR HQ
    Dear Friends, I am a novice in these things and therefore ask that you bear with me if my thoughts seem weird. 1. What is the reason for using a glass - based
    Message 1 of 28 , Jun 28, 2004
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      Dear Friends,

      I am a novice in these things and therefore ask that you bear with me if my
      thoughts seem weird.

      1. What is the reason for using a glass - based cloth?

      why not something that will accept proper impregnation like silk or cotton
      or other natural fibre.


      2. In the same area of thought. can one use something like corn flour or
      some other plant flour as a thickening agent for epoxy fillets, if not why?

      Thanks
      Marius

      Marius Lubbe
      Creative MindsR HQ
      Cape Town, South Africa
      Phone: 082 785 7763
      www.minds.co.za


      [Non-text portions of this message have been removed]
    • craig o'donnell
      ... Any flour will work. Cornstarch, powdered limestone, wood flour. -- Craig O Donnell Sinepuxent Ancestors & Boats
      Message 2 of 28 , Jun 28, 2004
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        >2. In the same area of thought. can one use something like corn flour or
        >some other plant flour as a thickening agent for epoxy fillets, if not why?

        Any flour will work. Cornstarch, powdered limestone, wood flour.
        --
        Craig O'Donnell
        Sinepuxent Ancestors & Boats
        <http://freepages.genealogy.rootsweb.com/~fassitt/>
        The Proa FAQ <http://boat-links.com/proafaq.html>
        The Cheap Pages <http://www.friend.ly.net/~dadadata/>
        Sailing Canoes, Polytarp Sails, Bamboo, Chinese Junks,
        American Proas, the Bolger Boat Honor Roll,
        Plywood Boats, Bamboo Rafts, &c.
        _________________________________

        -- Professor of Boatology -- Junkomologist
        -- Macintosh kinda guy
        Friend of Wanda the Wonder Cat, 1991-1997.
        _________________________________
      • craig o'donnell
        ... Strength, I imagine. You could use any cloth. Burlap, for example. Note that epoxy is heavier than the cloth, so you want something that will fill with
        Message 3 of 28 , Jun 28, 2004
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          >1. What is the reason for using a glass - based cloth?
          >
          >why not something that will accept proper impregnation like silk or cotton
          >or other natural fibre.

          Strength, I imagine. You could use any cloth. Burlap, for example.

          Note that epoxy is heavier than the cloth, so you want something that will
          fill with epoxy without soaking it up. Soaking the cloth only means more
          weight and more $ spent for epoxy.
          --
          Craig O'Donnell
          Sinepuxent Ancestors & Boats
          <http://freepages.genealogy.rootsweb.com/~fassitt/>
          The Proa FAQ <http://boat-links.com/proafaq.html>
          The Cheap Pages <http://www.friend.ly.net/~dadadata/>
          Sailing Canoes, Polytarp Sails, Bamboo, Chinese Junks,
          American Proas, the Bolger Boat Honor Roll,
          Plywood Boats, Bamboo Rafts, &c.
          _________________________________

          -- Professor of Boatology -- Junkomologist
          -- Macintosh kinda guy
          Friend of Wanda the Wonder Cat, 1991-1997.
          _________________________________
        • Roger Derby
          ... From: Marius Lubbe - Creative MindsR HQ ... Strength! Glass which is free of impurities and small fractures is one of the
          Message 4 of 28 , Jun 28, 2004
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            ----- Original Message -----
            From: "Marius Lubbe - Creative MindsR HQ" <marius@...>

            > 1. What is the reason for using a glass - based cloth?

            Strength! Glass which is free of impurities and small fractures is one of
            the strongest materials on earth. With fibers, the flaws have already
            broken. The combination of incredibly strong glass fibers with the elastic
            nature of the cured epoxy is what makes the result better than either
            element alone.

            > why not something that will accept proper impregnation like silk or cotton
            > or other natural fibre.

            Pretty weak stuff. Why add something that won't make the final product
            better? Fiberglass cloth from an epoxy vendor is coated to promote the
            bond.

            > 2. In the same area of thought. can one use something like corn flour or
            > some other plant flour as a thickening agent for epoxy fillets, if not
            why?

            Wood flour would seem to fall into this category, and it is my favorite
            filler. Other fillers offer different characteristics; e.g. lime for a hard
            coating, silica thickener for colorless coating, silicon carbide for
            incredible hardness, ...

            One purpose for a filler is to provide thixotropic properties. Unthickened
            epoxy runs and runs and runs. (A model railroader cast a fine lake of
            unthickened epoxy. The next morning, all of the epoxy was on the floor.
            He'd left a pinhole in the lake bed.) Not all additives provide this.

            Quoting from System Three's "The Epoxy Book:"
            SECTION VI C
            USING FILLERS WITH EPOXY RESIN
            System Three epoxy properly mixed is intended for both coating and
            fiberglassing. When used "right out of the jug", the mixture is said to be
            "unfilled" and it is too thin to be used as a gap filling adhesive or for
            fairing and filleting compounds. For these applications certain fillers are
            added. These materials change the flow and density characteristics of the
            epoxy system.

            All fillers sold for use with System Three epoxy products are solid
            materials, falling into four general classes: thixotropic agents, bulking
            agents, fibrous fillers, and pigments. There is some overlapping as to
            function of certain fillers. For example, plastic minifibers is both fibrous
            and acts also as a thixotropic agent.
            Silica thickener (Cab-O-Sil), plastic minifibers and wood flourare
            thixotropic agents. They turn the epoxy into a thixotropic fluid. Most
            people are not familiar with the term "thixotropic" though everyone is
            familiar with the properties of these fluids. They flow under shear stress
            but do not flow once the stress is removed. Ketchup and latex house paints
            are thixotropic fluids. Adding these agents to the mixed resin and hardener
            produces a fluid which will easily flow under the spreading stress of a
            putty knife. Once the stress is removed the thickened epoxy retains shape.
            In short, these fillers make the epoxy non-sagging, being added to restrict
            drainage and make gap filling adhesives.

            Phenolic microballoons, quartz microspheres, and wood flour are bulking
            agents. They "bulk out" the epoxy making a lightweight putty like mix.
            Although all these thicken the epoxy, only wood flour will make it
            thixotropic. Attempting to add sufficient microballoons or microspheres to
            make a non-sagging fairing putty will result in one that spreads poorly.
            These materials should be used along with a thixotropic agent. Silica
            thickener is the best choice because it produces the smoothest compound.

            Chopped glass strands, milled glass fibers, and plastic minifibers are
            fibrous materials that can be incorporated into structural filleting putties
            to improve tensile strength, and are listed above in descending order of
            tensile strength improvement.

            +++++++++++++++++++++++
            Lots of good stuff in this free publication, and it applies to most epoxy
            vendor's products.

            Roger
          • pvanderwaart
            ... They do say that silk is very strong. However, the has to be a match between the tensile and compressive strength coefficients between the fiber and the
            Message 5 of 28 , Jun 28, 2004
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              > > 1. What is the reason for using a glass - based cloth?
              > Strength!


              They do say that silk is very strong. However, the has to be a match
              between the tensile and compressive strength coefficients between
              the fiber and the resin. And I don't know if it would wet out
              properly, or if there is chemical compatibility.
            • Roger Derby
              Silk does ring a bell, but I ve no idea where to look further After pricing vinyl for smoothing, I m going to experiment further with Peel-Ply ... but that s
              Message 6 of 28 , Jun 28, 2004
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                Silk does ring a bell, but I've no idea where to look further After pricing
                vinyl for smoothing, I'm going to experiment further with Peel-Ply ... but
                that's the approach we don't want for reinforcing..

                Spider webs do well too, and here in Southern Indiana we have many, many,
                very industrious spiders drifting around on their one strand parachutes.
                You may be onto something here.

                Don't you need some kind of special tree to encourage/optimize silk worm
                production?

                Roger (Dow-Corning doesn't have the only effective spinerets.)
                derbyrm@...
                derbyrm.mystarband.net/default.htm

                ----- Original Message -----
                From: "pvanderwaart" <pvanderwaart@...>


                > > > 1. What is the reason for using a glass - based cloth?
                > > Strength!
                >
                > They do say that silk is very strong. However, the has to be a match
                > between the tensile and compressive strength coefficients between
                > the fiber and the resin. And I don't know if it would wet out
                > properly, or if there is chemical compatibility.
              • pvanderwaart
                ... silk worm ... Mulberry bushes, IIRC from elementary school. There was an annoucement lately about artifical silk production. I forget if it was straight
                Message 7 of 28 , Jun 28, 2004
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                  > Don't you need some kind of special tree to encourage/optimize
                  silk worm
                  > production?

                  Mulberry bushes, IIRC from elementary school.

                  There was an annoucement lately about artifical silk production. I
                  forget if it was straight chemical or if, more likely, it had to do
                  with putting a silkworm gene in a spider (or some other, more
                  tractable animal). I hope they don't put it in a cow!

                  Peter
                • Jason Stancil
                  They have put a spider gene in goats, so as the silk is produced in the goat s mammary glands. When the goat is milked the silk somehow precipitates into
                  Message 8 of 28 , Jun 28, 2004
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                    They have put a spider gene in goats, so as the silk is produced in
                    the goat's mammary glands. When the goat is milked the "silk"
                    somehow precipitates into strands out of the milk. Folks are looking
                    at develping this stuff for biodegradible fishing line and as a
                    suture material. Something like 200+ times(total guess i read this a
                    while back) stronger than steel

                    Glad to see biodegradable fishing line but kind of a scary way to go
                    about it.

                    Jason
                    --- In bolger@yahoogroups.com, "pvanderwaart" <pvanderwaart@y...>
                    wrote:
                    > > Don't you need some kind of special tree to encourage/optimize
                    > silk worm
                    > > production?
                    >
                    > Mulberry bushes, IIRC from elementary school.
                    >
                    > There was an annoucement lately about artifical silk production. I
                    > forget if it was straight chemical or if, more likely, it had to
                    do
                    > with putting a silkworm gene in a spider (or some other, more
                    > tractable animal). I hope they don't put it in a cow!
                    >
                    > Peter
                  • grant corson
                    I guess my first question would be why not use fiberglass cloth as it is a proven effective product. Aside from the fact that fibers can be irritating if used
                    Message 9 of 28 , Jun 28, 2004
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                      I guess my first question would be why not use fiberglass cloth as it is a
                      proven effective product. Aside from the fact that fibers can be irritating
                      if used carelessly it works well in boat building. To get away from the
                      itch dynel fabric is an excellent but more expensive alternative. Strong,
                      reliable and no itch.
                      Grant in Vermont about two weeks away from launching my repro 1929 cabin
                      cruiser (I hope)

                      on 6/28/04 6:12 AM, Marius Lubbe - Creative MindsR HQ at
                      marius@... wrote:

                      > Dear Friends,
                      >
                      > I am a novice in these things and therefore ask that you bear with me if my
                      > thoughts seem weird.
                      >
                      > 1. What is the reason for using a glass - based cloth?
                      >
                      > why not something that will accept proper impregnation like silk or cotton
                      > or other natural fibre.
                      >
                      >
                      > 2. In the same area of thought. can one use something like corn flour or
                      > some other plant flour as a thickening agent for epoxy fillets, if not why?
                      >
                      > Thanks
                      > Marius
                      >
                      > Marius Lubbe
                      > Creative MindsR HQ
                      > Cape Town, South Africa
                      > Phone: 082 785 7763
                      > www.minds.co.za
                      >
                      >
                      > [Non-text portions of this message have been removed]
                      >
                      >


                      >
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                      > (978) 282-1349
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                      >
                    • pvanderwaart
                      ... The cow idea was too close for comfort. But, if they put it in a fish, maybe it could net itself!
                      Message 10 of 28 , Jun 28, 2004
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                        > They have put a spider gene in goats,..

                        The cow idea was too close for comfort.

                        But, if they put it in a fish, maybe it could net itself!
                      • sacalman
                        ... Kind of brings a whole new meaning to belly button lint...8^0 Scott Calman
                        Message 11 of 28 , Jun 28, 2004
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                          --- In bolger@yahoogroups.com, "Jason Stancil" <jasonstancil@h...>
                          wrote:
                          > They have put a spider gene in goats, so as the silk is produced in
                          > the goat's mammary glands. When the goat is milked the "silk"
                          > somehow precipitates into strands out of the milk.

                          Kind of brings a whole new meaning to belly button lint...8^0

                          Scott Calman
                        • Lincoln Ross
                          Glass fibers are extremely strong, fairly elastic, and don t break down easily. If the proper type is used (especially don t use mat), they wet out just fine
                          Message 12 of 28 , Jun 28, 2004
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                            Glass fibers are extremely strong, fairly elastic, and don't break down
                            easily. If the proper type is used (especially don't use mat), they wet
                            out just fine with epoxy. I'm sure "natural" fibers are MUCH weaker. I
                            have used very small amounts of glass cloth with nitrocellulose dope
                            with good results, but I'd guess this is weaker than epoxy. In my
                            experience, 1 oz. glass and epoxy are enough to prevent checking and are
                            very light when applied carefully..

                            Some people have reported successful use of flour. You want something
                            very fine and smooth, like white wheat flour. I'm guessing mechanical
                            properties are much worse than fumed silica, but maybe enough if the
                            fillet is glassed over.

                            >Marius Lubbe - Creative MindsR HQ
                            >Dear Friends,
                            >
                            >I am a novice in these things and therefore ask that you bear with me if my
                            >thoughts seem weird.
                            >
                            >1. What is the reason for using a glass - based cloth?
                            >
                            >why not something that will accept proper impregnation like silk or cotton
                            >or other natural fibre.
                            >
                            >
                            >2. In the same area of thought. can one use something like corn flour or
                            >some other plant flour as a thickening agent for epoxy fillets, if not why?
                            >
                            >Thanks
                            >Marius
                            >
                          • Lincoln Ross
                            I m not sure what your source is, but I don t believe this figure. I just did a quick web search and got a figure of 200,000 psi. Then the same site says it s
                            Message 13 of 28 , Jun 28, 2004
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                              I'm not sure what your source is, but I don't believe this figure. I
                              just did a quick web search and got a figure of 200,000 psi. Then the
                              same site says it's several times that of steel. Not true. If you take a
                              piece of fine music wire, you can expect it to be stronger than that.
                              (Small Parts claims min. 220kpsi on their music wire). I recall Kevlar
                              and glass fibers are even stronger than that. And spider silk is very
                              stretchy, so the epoxy may fail first. THere are reasons we use glass
                              cloth on boats. (Kevlar, besides being expensive, is lousy in compression)

                              >snip Something like 200+ times(total guess i read this a
                              >while back) stronger than steel
                              >
                              >Glad to see biodegradable fishing line but kind of a scary way to go
                              >about it.
                              >
                              >Jason
                              >
                            • Howard Stephenson
                              And glass would be unattractive to micro-organisms (e.g. bacteria, fungi), whereas certain kinds might like to eat plant material or silk. Glass is also
                              Message 14 of 28 , Jun 28, 2004
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                                And glass would be unattractive to micro-organisms (e.g. bacteria,
                                fungi), whereas certain kinds might like to eat plant material or
                                silk. Glass is also more-or-less unaffected by most chemicals.

                                Same possible problem with using wood flour to thicken epoxy, both
                                chemical and biological. Limestone could be attacked by acids,
                                possibly even mildly acidic rainwater/ Think of how limestone caves
                                are formed.

                                Howard

                                --- In bolger@yahoogroups.com, "Roger Derby" <derbyrm@s...> wrote:
                                > ----- Original Message -----
                                > From: "Marius Lubbe - Creative MindsR HQ" <marius@c...>
                                >
                                > > 1. What is the reason for using a glass - based cloth?
                                >
                                > Strength! Glass which is free of impurities and small fractures is
                                one of
                                > the strongest materials on earth. With fibers, the flaws have
                                already
                                > broken. The combination of incredibly strong glass fibers with the
                                elastic
                                > nature of the cured epoxy is what makes the result better than
                                either
                                > element alone.
                                >
                                > > why not something that will accept proper impregnation like silk
                                or cotton
                                > > or other natural fibre.
                                >
                                > Pretty weak stuff. Why add something that won't make the final
                                product
                                > better? Fiberglass cloth from an epoxy vendor is coated to promote
                                the
                                > bond.
                                >
                                > > 2. In the same area of thought. can one use something like corn
                                flour or
                                > > some other plant flour as a thickening agent for epoxy fillets,
                                if not
                                > why?
                                >
                                > Wood flour would seem to fall into this category, and it is my
                                favorite
                                > filler. Other fillers offer different characteristics; e.g. lime
                                for a hard
                                > coating, silica thickener for colorless coating, silicon carbide for
                                > incredible hardness, ...
                                >
                                > One purpose for a filler is to provide thixotropic properties.
                                Unthickened
                                > epoxy runs and runs and runs. (A model railroader cast a fine lake
                                of
                                > unthickened epoxy. The next morning, all of the epoxy was on the
                                floor.
                                > He'd left a pinhole in the lake bed.) Not all additives provide
                                this.
                                >
                                > Quoting from System Three's "The Epoxy Book:"
                                > SECTION VI C
                                > USING FILLERS WITH EPOXY RESIN
                                > System Three epoxy properly mixed is intended for both coating and
                                > fiberglassing. When used "right out of the jug", the mixture is
                                said to be
                                > "unfilled" and it is too thin to be used as a gap filling adhesive
                                or for
                                > fairing and filleting compounds. For these applications certain
                                fillers are
                                > added. These materials change the flow and density characteristics
                                of the
                                > epoxy system.
                                >
                                > All fillers sold for use with System Three epoxy products are solid
                                > materials, falling into four general classes: thixotropic agents,
                                bulking
                                > agents, fibrous fillers, and pigments. There is some overlapping as
                                to
                                > function of certain fillers. For example, plastic minifibers is
                                both fibrous
                                > and acts also as a thixotropic agent.
                                > Silica thickener (Cab-O-Sil), plastic minifibers and wood flourare
                                > thixotropic agents. They turn the epoxy into a thixotropic fluid.
                                Most
                                > people are not familiar with the term "thixotropic" though everyone
                                is
                                > familiar with the properties of these fluids. They flow under
                                shear stress
                                > but do not flow once the stress is removed. Ketchup and latex house
                                paints
                                > are thixotropic fluids. Adding these agents to the mixed resin and
                                hardener
                                > produces a fluid which will easily flow under the spreading stress
                                of a
                                > putty knife. Once the stress is removed the thickened epoxy retains
                                shape.
                                > In short, these fillers make the epoxy non-sagging, being added to
                                restrict
                                > drainage and make gap filling adhesives.
                                >
                                > Phenolic microballoons, quartz microspheres, and wood flour are
                                bulking
                                > agents. They "bulk out" the epoxy making a lightweight putty like
                                mix.
                                > Although all these thicken the epoxy, only wood flour will make it
                                > thixotropic. Attempting to add sufficient microballoons or
                                microspheres to
                                > make a non-sagging fairing putty will result in one that spreads
                                poorly.
                                > These materials should be used along with a thixotropic agent.
                                Silica
                                > thickener is the best choice because it produces the smoothest
                                compound.
                                >
                                > Chopped glass strands, milled glass fibers, and plastic minifibers
                                are
                                > fibrous materials that can be incorporated into structural
                                filleting putties
                                > to improve tensile strength, and are listed above in descending
                                order of
                                > tensile strength improvement.
                                >
                                > +++++++++++++++++++++++
                                > Lots of good stuff in this free publication, and it applies to most
                                epoxy
                                > vendor's products.
                                >
                                > Roger
                              • Roger Derby
                                Sure, but glass is a fluid, and in a few thousand years, your hull shape will be quite pear shaped. Roger derbyrm@starband.net
                                Message 15 of 28 , Jun 28, 2004
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                                  Sure, but glass is a fluid, and in a few thousand years, your hull shape
                                  will be quite pear shaped.

                                  Roger
                                  derbyrm@...
                                  derbyrm.mystarband.net/default.htm

                                  ----- Original Message -----
                                  From: "Howard Stephenson" <stephensonhw@...>


                                  > And glass would be unattractive to micro-organisms (e.g. bacteria,
                                  > fungi), whereas certain kinds might like to eat plant material or
                                  > silk. Glass is also more-or-less unaffected by most chemicals.
                                  >
                                  > Same possible problem with using wood flour to thicken epoxy, both
                                  > chemical and biological. Limestone could be attacked by acids,
                                  > possibly even mildly acidic rainwater/ Think of how limestone caves
                                  > are formed.
                                  >
                                  > Howard

                                  > --- In bolger@yahoogroups.com, "Roger Derby" <derbyrm@s...> wrote:
                                  > > ----- Original Message -----
                                  > > From: "Marius Lubbe - Creative MindsR HQ" <marius@c...>
                                  > >
                                  > > > 1. What is the reason for using a glass - based cloth?
                                  > >
                                  > > Strength! Glass which is free of impurities and small fractures is
                                  > one of
                                  > > the strongest materials on earth. With fibers, the flaws have
                                  > already
                                  > > broken. The combination of incredibly strong glass fibers with the
                                  > elastic
                                  > > nature of the cured epoxy is what makes the result better than
                                  > either
                                  > > element alone.
                                  > >
                                  > > > why not something that will accept proper impregnation like silk
                                  > or cotton
                                  > > > or other natural fibre.
                                  > >
                                  > > Pretty weak stuff. Why add something that won't make the final
                                  > product
                                  > > better? Fiberglass cloth from an epoxy vendor is coated to promote
                                  > the
                                  > > bond.
                                  > >
                                  > > > 2. In the same area of thought. can one use something like corn
                                  > flour or
                                  > > > some other plant flour as a thickening agent for epoxy fillets,
                                  > if not
                                  > > why?
                                  > >
                                  > > Wood flour would seem to fall into this category, and it is my
                                  > favorite
                                  > > filler. Other fillers offer different characteristics; e.g. lime
                                  > for a hard
                                  > > coating, silica thickener for colorless coating, silicon carbide for
                                  > > incredible hardness, ...
                                  > >
                                  > > One purpose for a filler is to provide thixotropic properties.
                                  > Unthickened
                                  > > epoxy runs and runs and runs. (A model railroader cast a fine lake
                                  > of
                                  > > unthickened epoxy. The next morning, all of the epoxy was on the
                                  > floor.
                                  > > He'd left a pinhole in the lake bed.) Not all additives provide
                                  > this.
                                  > >
                                  > > Quoting from System Three's "The Epoxy Book:"
                                  > > SECTION VI C
                                  > > USING FILLERS WITH EPOXY RESIN
                                  > > System Three epoxy properly mixed is intended for both coating and
                                  > > fiberglassing. When used "right out of the jug", the mixture is
                                  > said to be
                                  > > "unfilled" and it is too thin to be used as a gap filling adhesive
                                  > or for
                                  > > fairing and filleting compounds. For these applications certain
                                  > fillers are
                                  > > added. These materials change the flow and density characteristics
                                  > of the
                                  > > epoxy system.
                                  > >
                                  > > All fillers sold for use with System Three epoxy products are solid
                                  > > materials, falling into four general classes: thixotropic agents,
                                  > bulking
                                  > > agents, fibrous fillers, and pigments. There is some overlapping as
                                  > to
                                  > > function of certain fillers. For example, plastic minifibers is
                                  > both fibrous
                                  > > and acts also as a thixotropic agent.
                                  > > Silica thickener (Cab-O-Sil), plastic minifibers and wood flourare
                                  > > thixotropic agents. They turn the epoxy into a thixotropic fluid.
                                  > Most
                                  > > people are not familiar with the term "thixotropic" though everyone
                                  > is
                                  > > familiar with the properties of these fluids. They flow under
                                  > shear stress
                                  > > but do not flow once the stress is removed. Ketchup and latex house
                                  > paints
                                  > > are thixotropic fluids. Adding these agents to the mixed resin and
                                  > hardener
                                  > > produces a fluid which will easily flow under the spreading stress
                                  > of a
                                  > > putty knife. Once the stress is removed the thickened epoxy retains
                                  > shape.
                                  > > In short, these fillers make the epoxy non-sagging, being added to
                                  > restrict
                                  > > drainage and make gap filling adhesives.
                                  > >
                                  > > Phenolic microballoons, quartz microspheres, and wood flour are
                                  > bulking
                                  > > agents. They "bulk out" the epoxy making a lightweight putty like
                                  > mix.
                                  > > Although all these thicken the epoxy, only wood flour will make it
                                  > > thixotropic. Attempting to add sufficient microballoons or
                                  > microspheres to
                                  > > make a non-sagging fairing putty will result in one that spreads
                                  > poorly.
                                  > > These materials should be used along with a thixotropic agent.
                                  > Silica
                                  > > thickener is the best choice because it produces the smoothest
                                  > compound.
                                  > >
                                  > > Chopped glass strands, milled glass fibers, and plastic minifibers
                                  > are
                                  > > fibrous materials that can be incorporated into structural
                                  > filleting putties
                                  > > to improve tensile strength, and are listed above in descending
                                  > order of
                                  > > tensile strength improvement.
                                  > >
                                  > > +++++++++++++++++++++++
                                  > > Lots of good stuff in this free publication, and it applies to most
                                  > epoxy
                                  > > vendor's products.
                                  > >
                                  > > Roger
                                  >
                                  >
                                  >
                                  >
                                  > Bolger rules!!!
                                  > - no cursing, flaming, trolling, spamming, or flogging dead horses
                                  > - stay on topic, stay on thread, punctuate, no 'Ed, thanks, Fred' posts
                                  > - Pls add your comments at the TOP, SIGN your posts, and snip away
                                  > - Plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA, 01930, Fax:
                                  (978) 282-1349
                                  > - Unsubscribe: bolger-unsubscribe@yahoogroups.com
                                  > - Open discussion: bolger_coffee_lounge-subscribe@yahoogroups.com
                                  > Yahoo! Groups Links
                                  >
                                  >
                                  >
                                  >
                                  >
                                  >
                                • chodges31711
                                  ... cotton ... You can use a polyester like Xynole. It is not a natural fiber but it does not itch like glass. That alone makes it easier to work with. Charles
                                  Message 16 of 28 , Jun 28, 2004
                                  • 0 Attachment
                                    >
                                    > 1. What is the reason for using a glass - based cloth?
                                    >
                                    > why not something that will accept proper impregnation like silk or
                                    cotton
                                    > or other natural fibre.

                                    You can use a polyester like Xynole. It is not a natural fiber but it
                                    does not itch like glass. That alone makes it easier to work with.

                                    Charles
                                  • Marius Lubbe - Creative MindsR HQ
                                    Hi Guys, This has been very interesting; especially those replies that says we use glass because its better......??? I take the point of the writer who said
                                    Message 17 of 28 , Jun 28, 2004
                                    • 0 Attachment
                                      Hi Guys,

                                      This has been very interesting; especially those replies that says we use
                                      glass because its better......???

                                      I take the point of the writer who said that natural fibres will suck up
                                      more epoxy and make the work heavier. That makes a lot of sense, and would
                                      be valid if you constructed a whole boat of just glass and resin. We however
                                      a looking for the most durable, easiest to work and most affordable solution
                                      for a single thin skin, that will also not check, (I believe its because the
                                      fibres repel the resin, somewhat)!

                                      My thoughts are (and please I not a scientist) that it seems to me that the
                                      resin is the thing that actually does the power thing, whereas the glass, or
                                      cloth or whatever seems to be the matrix that hold it all in shape and give
                                      it some bulk all over a large area in a uniform kind of way. My thinking was
                                      impregnated natural fibre would be stronger than glass strands which is (it
                                      seems to me at least) a weak material. For example: If they made a cheap
                                      stainless steel cloth would that not be a fantastic almost bullet-proof base
                                      cloth?

                                      You must please excuse my ignorance, but I am sure you will bear with my
                                      thinking somewhat out of the box. Actually it started with the book Backyard
                                      boatbuilding which suggest using anything that gets a boat together and
                                      floating. I am not looking to do that, but am wondering whether we are
                                      conditioned by DuPont & co.to use the glass, without thinking about it. BTW
                                      what was invented first ? the glass or the epoxy? Was glass fibres invented
                                      first and then they started looking for a binding agent, to make it useful
                                      as a construction material?

                                      I read somewhere about glass fibre boats not standing well up to knocks and
                                      cracking and crazing. Have you seen the little statuettes and models molded
                                      of resin. They look like they can stand being fired from a cannon, but still
                                      is not too heavy!

                                      Hope this is not starting to bore you, but I think we should explore all the
                                      alternatives.

                                      Regards
                                      Marius


                                      _____

                                      From: Lincoln Ross [mailto:lincolnr@...]
                                      Sent: Monday, June 28, 2004 9:28 PM
                                      To: bolger@yahoogroups.com
                                      Subject: [bolger] Re: Natural alternatives to Fibreglass cloth?


                                      Glass fibers are extremely strong, fairly elastic, and don't break down
                                      easily. If the proper type is used (especially don't use mat), they wet
                                      out just fine with epoxy. I'm sure "natural" fibers are MUCH weaker. I
                                      have used very small amounts of glass cloth with nitrocellulose dope
                                      with good results, but I'd guess this is weaker than epoxy. In my
                                      experience, 1 oz. glass and epoxy are enough to prevent checking and are
                                      very light when applied carefully..

                                      Some people have reported successful use of flour. You want something
                                      very fine and smooth, like white wheat flour. I'm guessing mechanical
                                      properties are much worse than fumed silica, but maybe enough if the
                                      fillet is glassed over.

                                      >Marius Lubbe - Creative MindsR HQ
                                      >Dear Friends,
                                      >
                                      >I am a novice in these things and therefore ask that you bear with me if my
                                      >thoughts seem weird.
                                      >
                                      >1. What is the reason for using a glass - based cloth?
                                      >
                                      >why not something that will accept proper impregnation like silk or cotton
                                      >or other natural fibre.
                                      >
                                      >
                                      >2. In the same area of thought. can one use something like corn flour or
                                      >some other plant flour as a thickening agent for epoxy fillets, if not why?
                                      >
                                      >Thanks
                                      >Marius
                                      >




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                                      [Non-text portions of this message have been removed]
                                    • David Romasco
                                      Yes, and it absorbs epoxy like a sponge! I like most of xynole s properties, but unless you are very careful in wetting it out it will turn into a heavy and
                                      Message 18 of 28 , Jun 29, 2004
                                      • 0 Attachment
                                        Yes, and it absorbs epoxy like a sponge! I like most of xynole's
                                        properties, but unless you are very careful in wetting it out it will turn
                                        into a heavy and expensive coating.

                                        David

                                        _____

                                        From: chodges31711 [mailto:chodges@...]
                                        Sent: Monday, June 28, 2004 9:27 PM
                                        To: bolger@yahoogroups.com
                                        Subject: [bolger] Re: Natural alternatives to Fibreglass cloth?


                                        >
                                        > 1. What is the reason for using a glass - based cloth?
                                        >
                                        > why not something that will accept proper impregnation like silk or
                                        cotton
                                        > or other natural fibre.

                                        You can use a polyester like Xynole. It is not a natural fiber but it
                                        does not itch like glass. That alone makes it easier to work with.

                                        Charles



                                        Bolger rules!!!
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                                        (978) 282-1349
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                                        [Non-text portions of this message have been removed]
                                      • Roger Derby
                                        ... From: Lincoln Ross ... Amen! I overdid it on Dadink and it came out at 100 lbs instead of the 80 lbs it was supposed to. Glassing
                                        Message 19 of 28 , Jun 29, 2004
                                        • 0 Attachment
                                          ----- Original Message -----
                                          From: "Lincoln Ross" <lincolnr@...>

                                          > Actually, for small boats of 1/4" (6mm) plywood, the
                                          > fabric and epoxy weight can be very significant.

                                          Amen! I overdid it on Dadink and it came out at 100 lbs instead of the 80
                                          lbs it was supposed to. Glassing the inside was a mistake.

                                          > I have the impression that glass cloth was used with
                                          > polyester resin first.

                                          I think it was probably phenolic (which may be the same thing) and the
                                          initial boards used paper, then linen, then fiberglass. I've got some
                                          circuit components from the WW I era, and most steps in between. Anybody in
                                          the market for a few dozen vacuum tube shields?

                                          Roger
                                          derbyrm@...
                                          derbyrm.mystarband.net/default.htm
                                        • Lincoln Ross
                                          ... Actually, for small boats of 1/4 (6mm) plywood, the fabric and epoxy weight can be very significant. Particularly if you have to pick the boat up. I seem
                                          Message 20 of 28 , Jun 29, 2004
                                          • 0 Attachment
                                            >
                                            >
                                            >Marius Lubbe wrote:
                                            >Hi Guys,
                                            >snip
                                            >I take the point of the writer who said that natural fibres will suck up
                                            >more epoxy and make the work heavier. That makes a lot of sense, and would
                                            >be valid if you constructed a whole boat of just glass and resin. We however
                                            >a looking for the most durable, easiest to work and most affordable solution
                                            >for a single thin skin, that will also not check, (I believe its because the
                                            >fibres repel the resin, somewhat)!
                                            >
                                            Actually, for small boats of 1/4" (6mm) plywood, the fabric and epoxy
                                            weight can be very significant. Particularly if you have to pick the
                                            boat up. I seem to recall using most of a gallon on a dinghy. Probably 7
                                            or 8 lbs. of epoxy and some additional weight of fabric. I'm not sure,
                                            but I think the total weight of that boat is 60 lbs or less, so a large
                                            fraction is in the coating and in the tapes. . I used 1 oz glass for the
                                            coating, but it's not all that easy to use. Sure is cheap, tho.

                                            >
                                            >My thoughts are (and please I not a scientist) that it seems to me that the
                                            >resin is the thing that actually does the power thing, whereas the glass, or
                                            >cloth or whatever seems to be the matrix that hold it all in shape and give
                                            >it some bulk all over a large area in a uniform kind of way. My thinking was
                                            >impregnated natural fibre would be stronger than glass strands which is (it
                                            >seems to me at least) a weak material. For example: If they made a cheap
                                            >stainless steel cloth would that not be a fantastic almost bullet-proof base
                                            >cloth?
                                            >
                                            Glass fibers are very different from glass in your window. They are VERY
                                            strong, comparable to carbon fiber (but not as stiff), 500,000 psi for
                                            e glass (s glass is even stronger) according to a quick web search.
                                            Glass fibers are pretty floppy compared to carbon, though. Also, any
                                            such composite (including carbon, kevlar, etc.) will be much weaker than
                                            the individual fibers. My guess is that on really thin coatings (less
                                            epoxy, mind you), the glass helps to prevent checking with its superior
                                            strength. I also guess that a coating with natural fibers would have to
                                            be thicker to do the same job.

                                            >
                                            >You must please excuse my ignorance, but I am sure you will bear with my
                                            >thinking somewhat out of the box. Actually it started with the book Backyard
                                            >boatbuilding which suggest using anything that gets a boat together and
                                            >floating. I am not looking to do that, but am wondering whether we are
                                            >conditioned by DuPont & co.to use the glass, without thinking about it. BTW
                                            >what was invented first ? the glass or the epoxy? Was glass fibres invented
                                            >first and then they started looking for a binding agent, to make it useful
                                            >as a construction material?
                                            >
                                            Well, I don't think anyone has a monopoly anymore, if they ever did, and
                                            glass is as cheap as any other fabric I've seen, or maybe cheaper. I
                                            believe glass cloth and epoxy were invented seperately. I recall hearing
                                            that lots of circuit boards were made out of glass cloth for WW2 and
                                            afterwards all this surplus material was lying around.... I have the
                                            impression that glass cloth was used with polyester resin first.

                                            >
                                            >I read somewhere about glass fibre boats not standing well up to knocks and
                                            >cracking and crazing. Have you seen the little statuettes and models molded
                                            >of resin. They look like they can stand being fired from a cannon, but still
                                            >is not too heavy!
                                            >
                                            >
                                            I'll bet these boats were made with polyester resin, which is not as
                                            resilient as epoxy. And even then, in my experience polyester resin and
                                            glass can stand up to some pretty hard knocks. I suspect those "resin"
                                            models are something else entirely. THere are about a gazillion plastics
                                            available these days. Epoxy would probably be too slow to make any money
                                            out of those expensive molds.

                                            >Hope this is not starting to bore you, but I think we should explore all the
                                            >alternatives.
                                            >
                                            >Regards
                                            >Marius
                                            >
                                          • donschultz8275
                                            ........My thoughts are (and please I not a scientist) that it seems to me that the resin is the thing that actually does the power thing, whereas the glass,
                                            Message 21 of 28 , Jun 29, 2004
                                            • 0 Attachment
                                              ........My thoughts are (and please I not a scientist) that it seems
                                              to me that the resin is the thing that actually does the power thing,
                                              whereas the glass, or cloth or whatever seems to be the matrix that
                                              hold it all in shape and give it some bulk all over a large area in a
                                              uniform kind of way............


                                              Actually you have it almost entirely backwards. The resin holds the
                                              shape and resists some compression loads, while the fibers provide
                                              the strength in most every tension load.

                                              This is always true, even in ferro/cement construction. The steel is
                                              the strength. The cement does little more than keep the water out.

                                              It is also true that the fibers MUST resist tension loads as even a
                                              little stretch will crack, crumble, and otherwise wreck the resin.

                                              30 years ago there was a homebuilt aircraft which became popular
                                              using a polyester varient fabric and epoxy w' foam as a internal
                                              mold. If overstressed, the the epoxy broke up and the plane became a
                                              cloth bag as it fell to earth.
                                            • Marius Lubbe - Creative MindsR HQ
                                              Listen guys, I want to thank you for sharing, I am learning quickly. Thanks to everyone, there are too many to name, but I am grateful, and hope to be able to
                                              Message 22 of 28 , Jun 29, 2004
                                              • 0 Attachment
                                                Listen guys,

                                                I want to thank you for sharing, I am learning quickly. Thanks to everyone,
                                                there are too many to name, but I am grateful, and hope to be able to ask
                                                some more "dumb" questions in the future, and being treated in the same kind
                                                and respectful way!

                                                Kind regards
                                                Marius

                                                Marius Lubbe
                                                Creative MindsR HQ
                                                Cape Town, South Africa
                                                Phone: 082 785 7763

                                                _____

                                                From: donschultz8275 [mailto:donschultz@...]
                                                Sent: Wednesday, June 30, 2004 12:27 AM
                                                To: bolger@yahoogroups.com
                                                Subject: [bolger] Re: Natural alternatives to Fibreglass cloth?


                                                ........My thoughts are (and please I not a scientist) that it seems
                                                to me that the resin is the thing that actually does the power thing,
                                                whereas the glass, or cloth or whatever seems to be the matrix that
                                                hold it all in shape and give it some bulk all over a large area in a
                                                uniform kind of way............


                                                Actually you have it almost entirely backwards. The resin holds the
                                                shape and resists some compression loads, while the fibers provide
                                                the strength in most every tension load.

                                                This is always true, even in ferro/cement construction. The steel is
                                                the strength. The cement does little more than keep the water out.

                                                It is also true that the fibers MUST resist tension loads as even a
                                                little stretch will crack, crumble, and otherwise wreck the resin.

                                                30 years ago there was a homebuilt aircraft which became popular
                                                using a polyester varient fabric and epoxy w' foam as a internal
                                                mold. If overstressed, the the epoxy broke up and the plane became a
                                                cloth bag as it fell to earth.



                                                Bolger rules!!!
                                                - no cursing, flaming, trolling, spamming, or flogging dead horses
                                                - stay on topic, stay on thread, punctuate, no 'Ed, thanks, Fred' posts
                                                - Pls add your comments at the TOP, SIGN your posts, and snip away
                                                - Plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA, 01930, Fax:
                                                (978) 282-1349
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                                                [Non-text portions of this message have been removed]
                                              • Marius Lubbe - Creative MindsR HQ
                                                Thanks Lincoln, I did not think of it that way, the cloth absorbing could actually make the hull a hell of a lot heavier. Not good!! hey? Thanks for the
                                                Message 23 of 28 , Jun 30, 2004
                                                • 0 Attachment
                                                  Thanks Lincoln,

                                                  I did not think of it that way, the cloth absorbing could actually make the
                                                  hull a hell of a lot heavier. Not good!! hey?

                                                  Thanks for the answers I appreciate the kindness.

                                                  Whenever in stunning Cape Town - South Africa, you know my number!!

                                                  Regards
                                                  Marius

                                                  Marius Lubbe
                                                  Creative MindsR HQ
                                                  Cape Town, South Africa
                                                  Phone: 082 785 7763
                                                  w <http://www.minds.co.za> ww.minds.co.za


                                                  _____

                                                  From: Lincoln Ross [mailto:lincolnr@...]
                                                  Sent: Tuesday, June 29, 2004 11:31 PM
                                                  To: bolger@yahoogroups.com
                                                  Subject: [bolger] RE: Re: Natural alternatives to Fibreglass cloth?


                                                  >
                                                  >
                                                  >Marius Lubbe wrote:
                                                  >Hi Guys,
                                                  >snip
                                                  >I take the point of the writer who said that natural fibres will suck up
                                                  >more epoxy and make the work heavier. That makes a lot of sense, and would
                                                  >be valid if you constructed a whole boat of just glass and resin. We
                                                  however
                                                  >a looking for the most durable, easiest to work and most affordable
                                                  solution
                                                  >for a single thin skin, that will also not check, (I believe its because
                                                  the
                                                  >fibres repel the resin, somewhat)!
                                                  >
                                                  Actually, for small boats of 1/4" (6mm) plywood, the fabric and epoxy
                                                  weight can be very significant. Particularly if you have to pick the
                                                  boat up. I seem to recall using most of a gallon on a dinghy. Probably 7
                                                  or 8 lbs. of epoxy and some additional weight of fabric. I'm not sure,
                                                  but I think the total weight of that boat is 60 lbs or less, so a large
                                                  fraction is in the coating and in the tapes. . I used 1 oz glass for the
                                                  coating, but it's not all that easy to use. Sure is cheap, tho.

                                                  >
                                                  >My thoughts are (and please I not a scientist) that it seems to me that the
                                                  >resin is the thing that actually does the power thing, whereas the glass,
                                                  or
                                                  >cloth or whatever seems to be the matrix that hold it all in shape and give
                                                  >it some bulk all over a large area in a uniform kind of way. My thinking
                                                  was
                                                  >impregnated natural fibre would be stronger than glass strands which is (it
                                                  >seems to me at least) a weak material. For example: If they made a cheap
                                                  >stainless steel cloth would that not be a fantastic almost bullet-proof
                                                  base
                                                  >cloth?
                                                  >
                                                  Glass fibers are very different from glass in your window. They are VERY
                                                  strong, comparable to carbon fiber (but not as stiff), 500,000 psi for
                                                  e glass (s glass is even stronger) according to a quick web search.
                                                  Glass fibers are pretty floppy compared to carbon, though. Also, any
                                                  such composite (including carbon, kevlar, etc.) will be much weaker than
                                                  the individual fibers. My guess is that on really thin coatings (less
                                                  epoxy, mind you), the glass helps to prevent checking with its superior
                                                  strength. I also guess that a coating with natural fibers would have to
                                                  be thicker to do the same job.

                                                  >
                                                  >You must please excuse my ignorance, but I am sure you will bear with my
                                                  >thinking somewhat out of the box. Actually it started with the book
                                                  Backyard
                                                  >boatbuilding which suggest using anything that gets a boat together and
                                                  >floating. I am not looking to do that, but am wondering whether we are
                                                  >conditioned by DuPont & co.to use the glass, without thinking about it. BTW
                                                  >what was invented first ? the glass or the epoxy? Was glass fibres invented
                                                  >first and then they started looking for a binding agent, to make it useful
                                                  >as a construction material?
                                                  >
                                                  Well, I don't think anyone has a monopoly anymore, if they ever did, and
                                                  glass is as cheap as any other fabric I've seen, or maybe cheaper. I
                                                  believe glass cloth and epoxy were invented seperately. I recall hearing
                                                  that lots of circuit boards were made out of glass cloth for WW2 and
                                                  afterwards all this surplus material was lying around.... I have the
                                                  impression that glass cloth was used with polyester resin first.

                                                  >
                                                  >I read somewhere about glass fibre boats not standing well up to knocks and
                                                  >cracking and crazing. Have you seen the little statuettes and models molded
                                                  >of resin. They look like they can stand being fired from a cannon, but
                                                  still
                                                  >is not too heavy!
                                                  >
                                                  >
                                                  I'll bet these boats were made with polyester resin, which is not as
                                                  resilient as epoxy. And even then, in my experience polyester resin and
                                                  glass can stand up to some pretty hard knocks. I suspect those "resin"
                                                  models are something else entirely. THere are about a gazillion plastics
                                                  available these days. Epoxy would probably be too slow to make any money
                                                  out of those expensive molds.

                                                  >Hope this is not starting to bore you, but I think we should explore all
                                                  the
                                                  >alternatives.
                                                  >
                                                  >Regards
                                                  >Marius
                                                  >




                                                  Bolger rules!!!
                                                  - no cursing, flaming, trolling, spamming, or flogging dead horses
                                                  - stay on topic, stay on thread, punctuate, no 'Ed, thanks, Fred' posts
                                                  - Pls add your comments at the TOP, SIGN your posts, and snip away
                                                  - Plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA, 01930, Fax:
                                                  (978) 282-1349
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                                                • Justin Meddock
                                                  Not really natural, but I have a couple of old delaminating Mylar/Kevlar sails laying around. I was thinking of pulling the mylar off and using the kevlar
                                                  Message 24 of 28 , Jun 30, 2004
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                                                    Not really natural, but I have a couple of old delaminating
                                                    Mylar/Kevlar sails laying around. I was thinking of pulling the mylar off
                                                    and using the kevlar cloth for FG repair work.

                                                    Justin
                                                  • Roger Derby
                                                    You probably want to test the bond between epoxy and the salvaged Kevlar real well before you invest too much labor. I understand that most fibers for our work
                                                    Message 25 of 28 , Jun 30, 2004
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                                                      You probably want to test the bond between epoxy and the salvaged Kevlar
                                                      real well before you invest too much labor.

                                                      I understand that most fibers for our work are coated with something to
                                                      encourage the epoxy to "wet" them. The sail material might be coated
                                                      differently. (One can't imagine the many different kinds of glass until
                                                      he's visited the Corning Glass Museum in Corning, New York.)

                                                      Roger
                                                      derbyrm@...
                                                      derbyrm.mystarband.net/default.htm

                                                      ----- Original Message -----
                                                      From: "Justin Meddock" <jmeddock@...>
                                                      To: <bolger@yahoogroups.com>
                                                      Sent: Wednesday, June 30, 2004 7:21 AM
                                                      Subject: Re: [bolger] Re: Natural alternatives to Fibreglass cloth?


                                                      > Not really natural, but I have a couple of old delaminating
                                                      > Mylar/Kevlar sails laying around. I was thinking of pulling the mylar off
                                                      > and using the kevlar cloth for FG repair work.
                                                    • Lincoln Ross
                                                      The fiber provides compression strength too. The epoxy (or polyester resin) just holds it in place so it doesn t buckle. And maybe some local strength across
                                                      Message 26 of 28 , Jun 30, 2004
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                                                        The fiber provides compression strength too. The epoxy (or polyester
                                                        resin) just holds it in place so it doesn't buckle. And maybe some local
                                                        strength across the fibers. I seem to recall typical figures for
                                                        strength of laminates in the tens of thousands of psi, but strength
                                                        figures for epoxy under 10kpsi. I think with ferro cement, the cement
                                                        might be able to take more of the compression load, as you describe,
                                                        and as I recall portland cement is ok in compression and terrible in
                                                        tension. I also seem to recall epoxy has some strength in both tension
                                                        and compression, but nothing like what you see with glass added.

                                                        >donschultz8275 wrote:
                                                        >snip
                                                        >Actually you have it almost entirely backwards. The resin holds the
                                                        >shape and resists some compression loads, while the fibers provide
                                                        >the strength in most every tension load.
                                                        >
                                                        >This is always true, even in ferro/cement construction. The steel is
                                                        >the strength. The cement does little more than keep the water out.
                                                        >
                                                        >It is also true that the fibers MUST resist tension loads as even a
                                                        >little stretch will crack, crumble, and otherwise wreck the resin.
                                                        >
                                                        >
                                                        snip
                                                        BTW, what was that aircraft that turned into a bag?
                                                      • chodges31711
                                                        Standard concrete like that in your driveway and most structural concrete is 3000 psi minimum in 28 days. You can buy harder mixes, up to 6000 psi, if you need
                                                        Message 27 of 28 , Jul 1, 2004
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                                                          Standard concrete like that in your driveway and most structural
                                                          concrete is 3000 psi minimum in 28 days. You can buy harder mixes,
                                                          up to 6000 psi, if you need it to resist higher point loading like
                                                          bulldozer cleats or vibrating machines. There are different types of
                                                          cement and many different admixtures.

                                                          Structural steel, ASTM A36, has a minimum yield point of 36,000 psi.
                                                          Most structural shapes are also available in a high strength steel
                                                          that is 50,000 psi minimum.

                                                          Charles

                                                          but strength
                                                          > figures for epoxy under 10kpsi. I think with ferro cement, the
                                                          cement
                                                          > might be able to take more of the compression load, as you
                                                          describe,
                                                          > and as I recall portland cement is ok in compression and terrible
                                                          in
                                                          > tension. I also seem to recall epoxy has some strength in both
                                                          tension
                                                          > and compression, but nothing like what you see with glass added.
                                                          ?
                                                        • rogerleroy
                                                          Just buy the darn fiberglass and be done with it! It ll be much easier to deal with, as strong, and your boat will be back in the water in no time! It is
                                                          Message 28 of 28 , Jul 1, 2004
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                                                            Just buy the darn fiberglass and be done with it!
                                                            It'll be much easier to deal with, as strong, and your boat will be
                                                            back in the water in no time!
                                                            It is summer after all... at least here on Cape Cod...!
                                                            Cheers!
                                                            :-)

                                                            --- In bolger@yahoogroups.com, "Justin Meddock" <jmeddock@n...>
                                                            wrote:
                                                            > Not really natural, but I have a couple of old delaminating
                                                            > Mylar/Kevlar sails laying around. I was thinking of pulling the
                                                            mylar off
                                                            > and using the kevlar cloth for FG repair work.
                                                            >
                                                            > Justin
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