Loading ...
Sorry, an error occurred while loading the content.
 

Epoxy over Polyester?

Expand Messages
  • Bill
    This is my 16 year old son s idea: I was discussing the pros and cons of both polyester and epoxy resins with him. He says Why don t you just build your boat
    Message 1 of 8 , Aug 31, 2011
      This is my 16 year old son's idea:

      I was discussing the pros and cons of both polyester and epoxy resins with him.
      He says "Why don't you just build your boat with polyester then coat the whole
      thing with epoxy?".

      What say you?
    • Mark Albanese
      Fresh epoxy sticks to cured polyester; polyester not to epoxy. Why, though? Unless a very large boat or solid fg, not much economy in it. ... [Non-text
      Message 2 of 8 , Aug 31, 2011
        Fresh epoxy sticks to cured polyester; polyester not to epoxy. Why,
        though? Unless a very large boat or solid fg, not much economy in it.


        On Aug 31, 2011, at 6:14 PM, Bill wrote:

        > This is my 16 year old son's idea:
        >
        > I was discussing the pros and cons of both polyester and epoxy
        > resins with him.
        > He says "Why don't you just build your boat with polyester then
        > coat the whole
        > thing with epoxy?".
        >
        > What say you?
        >
        >



        [Non-text portions of this message have been removed]
      • Andres Espino
        Polyester is cheaper and hardens to a more brittle consistency.. Epoxy is more expensive and remains slightly more flexible but over polyester who cares. Your
        Message 3 of 8 , Aug 31, 2011
          Polyester is cheaper and hardens to a more brittle consistency.. Epoxy is more expensive and remains slightly more flexible but over polyester who cares.

          Your son's idea would certainly work but at a cost of serious overkill.  The additional costs could amount to several hundred dollars for a whole boat.

          One usually matches what was there and only if in doubt uses epoxy.

          Remember epoxy will bond over polyester but polyester will not bond well over epoxy.

          Most use epoxy when they need a spot repair over an unknown sublayer.

          Andrew



          ________________________________
          From: Bill <billwrin@...>
          To: Michalak@yahoogroups.com
          Sent: Wednesday, August 31, 2011 8:14 PM
          Subject: [Michalak] Epoxy over Polyester?


           
          This is my 16 year old son's idea:

          I was discussing the pros and cons of both polyester and epoxy resins with him.
          He says "Why don't you just build your boat with polyester then coat the whole
          thing with epoxy?".

          What say you?




          [Non-text portions of this message have been removed]
        • Carl
          If your going to build your boat out of fiberglass it might work but if wood, poly s not a good adhesive. ... From: Bill To: Michalak@yahoogroups.com Sent:
          Message 4 of 8 , Aug 31, 2011
            If your going to build your boat out of fiberglass it might work but if wood, poly's not a good adhesive.
            ----- Original Message -----
            From: Bill
            To: Michalak@yahoogroups.com
            Sent: Wednesday, August 31, 2011 6:14 PM
            Subject: [Michalak] Epoxy over Polyester?



            This is my 16 year old son's idea:

            I was discussing the pros and cons of both polyester and epoxy resins with him.
            He says "Why don't you just build your boat with polyester then coat the whole
            thing with epoxy?".

            What say you?





            [Non-text portions of this message have been removed]
          • KEN
            if the concern is for hardness-toughness abrasion resistance.. get some graphite powder to mix into one part of the epoxy resin thoroughly before mixing in the
            Message 5 of 8 , Sep 1, 2011
              if the concern is for hardness-toughness abrasion resistance.. get some graphite powder to mix into one part of the epoxy resin thoroughly before mixing in the other part to harden?
              it'd do a bottom good, possibly better if covered in epoxy and light cloth first, then another layer cloth with the epoxy+graphite mix. the lighter cloth like 6oz isnt all that spendy and comes in like 52-54" width sure is convenient for a 48" wide bottom to overlap up the sides a couple inches.. same for sides overlapping onto the bottom so the chines get double layered over, so if going 2 layers bottom its now 3 at the chines, 4 if the seams are taped first is getting into being darn near bulletproof. after 1/2 sanding and dust cleaning, the last smoothing coats being epoxy with the graphite in it too, to cover-fill any cloth texture before sanding primering sanding and painting.. much as I dislike sanding I do an awful lot of it.. but its nice when its time for washing-waxing etc.
               
              I've worked polyester and epoxy both, with a preference for the epoxy for it being thinner and runnier. I think it goes further and saturates the cloth better, so it really doesnt come up being more expensive is my opinion, when it comes to covering the sq footage.
              it might be just my opinion again, I'd rather go 2 layers in lighter cloth than one layer of thicker stuff, kinda thinking more control, more laminations, maybe higher thread count too.
              thats how I'd go at it, if wanting to make a wood hull much tougher.
               
              fiberglasssite.com is pretty reasonable on supplies, cloth and fresh resins as well as the powdered graphite stuff.
               
               


              --- On Thu, 9/1/11, Carl <shnarg@...> wrote:


              From: Carl <shnarg@...>
              Subject: Re: [Michalak] Epoxy over Polyester?
              To: Michalak@yahoogroups.com
              Date: Thursday, September 1, 2011, 1:08 AM


               



              If your going to build your boat out of fiberglass it might work but if wood, poly's not a good adhesive.
              ----- Original Message -----
              From: Bill
              To: Michalak@yahoogroups.com
              Sent: Wednesday, August 31, 2011 6:14 PM
              Subject: [Michalak] Epoxy over Polyester?

              This is my 16 year old son's idea:

              I was discussing the pros and cons of both polyester and epoxy resins with him.
              He says "Why don't you just build your boat with polyester then coat the whole
              thing with epoxy?".

              What say you?

              [Non-text portions of this message have been removed]
            • Robert
              When deciding whether to purchase polyester or epoxy for my first build (just starting) I found out that the price did not have to be that much different for
              Message 6 of 8 , Sep 1, 2011
                When deciding whether to purchase polyester or epoxy for my first build
                (just starting) I found out that the price did not have to be that much
                different for epoxy. I was unable to find $20 polyester locally. It was
                $35 or more. I found this site and the 1 1/2 gallon epoxy kit (slow)
                worked out to $48 a gallon in the gallon and a half kit for the slow
                hardner and less for medium or fast. I got the slow and it is a dream to
                work with in 95 degree Florida weather. Anywhere else, get medium or
                fast!

                http://www.uscomposites.com/epoxy.html
                <http://www.uscomposites.com/epoxy.html>


                --- In Michalak@yahoogroups.com, "Bill" <billwrin@...> wrote:
                >
                > This is my 16 year old son's idea:
                >
                > I was discussing the pros and cons of both polyester and epoxy resins
                with him.
                > He says "Why don't you just build your boat with polyester then coat
                the whole
                > thing with epoxy?".
                >
                > What say you?
                >




                [Non-text portions of this message have been removed]
              • Andres Espino
                I like epoxy for a building project. HOWEVER if you have bought a vintagebefopre the 80 s  plastic classic to make into your microcruiser.. it was probably
                Message 7 of 8 , Sep 1, 2011
                  I like epoxy for a building project.

                  HOWEVER if you have bought a vintagebefopre the 80's  'plastic classic' to make into your microcruiser.. it was probably built using polyester resin, so in that case polyester is okay to use to patch it.

                  I admit that i use far more epoxy than polyester anymore.

                  Andrew




                  ________________________________
                  From: Robert <footstepfollower@...>
                  To: Michalak@yahoogroups.com
                  Sent: Thursday, September 1, 2011 4:58 AM
                  Subject: [Michalak] Re: Epoxy over Polyester?


                   

                  When deciding whether to purchase polyester or epoxy for my first build
                  (just starting) I found out that the price did not have to be that much
                  different for epoxy. I was unable to find $20 polyester locally. It was
                  $35 or more. I found this site and the 1 1/2 gallon epoxy kit (slow)
                  worked out to $48 a gallon in the gallon and a half kit for the slow
                  hardner and less for medium or fast. I got the slow and it is a dream to
                  work with in 95 degree Florida weather. Anywhere else, get medium or
                  fast!

                  http://www.uscomposites.com/epoxy.html
                  <http://www.uscomposites.com/epoxy.html>

                  --- In Michalak@yahoogroups.com, "Bill" <billwrin@...> wrote:
                  >
                  > This is my 16 year old son's idea:
                  >
                  > I was discussing the pros and cons of both polyester and epoxy resins
                  with him.
                  > He says "Why don't you just build your boat with polyester then coat
                  the whole
                  > thing with epoxy?".
                  >
                  > What say you?
                  >

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




                  [Non-text portions of this message have been removed]
                • Chris
                  The cost difference between polyester resin and epoxy is not that great. For example US Composites pricing Epoxy 7.5 gallon kit cost $303.00 7.5 gallons of
                  Message 8 of 8 , Sep 1, 2011
                    The cost difference between polyester resin and epoxy is not that great. For example

                    US Composites pricing
                    Epoxy 7.5 gallon kit cost $303.00
                    7.5 gallons of polyester resin at $30.00 would cost $225.00

                    That's just a $75.00 difference on a fairly large project. This much epoxy would be enough to build a fairly large boat.

                    --- In Michalak@yahoogroups.com, "Bill" <billwrin@...> wrote:
                    >
                    > This is my 16 year old son's idea:
                    >
                    > I was discussing the pros and cons of both polyester and epoxy resins with him.
                    > He says "Why don't you just build your boat with polyester then coat the whole
                    > thing with epoxy?".
                    >
                    > What say you?
                    >
                  Your message has been successfully submitted and would be delivered to recipients shortly.