Polyester vs Epoxy resin for dinghy/kayak construction?

<koosvander.RemoveThis@gmail.com> wrote:

> What are the relative merits of polyester resin vs epoxy resin?

Trying to compare polyester and woven roving to epoxy and knitted
glass is like trying to compare oranges and apples.

Both are "fiberglass" laminates, but the similarity ends there.

About the best you get is 35%glass/65%resin using woven roving, mat,
and polyester.

OTOH, it is quite common to get a 50%glass/50%resin using knitted
glass and epoxy. This laminate does not require any mat.

Bottom line....................

Polyester/roving produces a rather brittle, heavy laminate.

Epoxy/knitted glass produces a more ductile, lighter weight laminate.

Pound for pound, polyester and woven roving cost less per pound, but
you use more pounds, so the cost differences tend to disappear.

Epoxy, knitted glass and a 1/2" Airex foam core would produce a very
light weight, bullet proof, dinghy or kayak.

Just remember three things.

1)You will buy a commercial dinghy for less money than you will spend
to build one.

2)You build one because you want to do it.

3)Once you use epoxy and knitted glass, you will never consider
polyester again.

Lew
 >> Stay informed about: Polyester vs Epoxy resin for dinghy/kayak construction? 

<koosvander DeleteThis @gmail.com> wrote:

> What are the relative merits of polyester resin vs epoxy resin?

Trying to compare polyester and woven roving to epoxy and knitted
glass is like trying to compare oranges and apples.

Both are "fiberglass" laminates, but the similarity ends there.

About the best you get is 35%glass/65%resin using woven roving, mat,
and polyester.

OTOH, it is quite common to get a 50%glass/50%resin using knitted
glass and epoxy. This laminate does not require any mat.

Bottom line....................

Polyester/roving produces a rather brittle, heavy laminate.

Epoxy/knitted glass produces a more ductile, lighter weight laminate.

Pound for pound, polyester and woven roving cost less per pound, but
you use more pounds, so the cost differences tend to disappear.

Epoxy, knitted glass and a 1/2" Airex foam core would produce a very
light weight, bullet proof, dinghy or kayak.

Just remember three things.

1)You will buy a commercial dinghy for less money than you will spend
to build one.

2)You build one because you want to do it.

3)Once you use epoxy and knitted glass, you will never consider
polyester again.

Lew
 >> Stay informed about: Polyester vs Epoxy resin for dinghy/kayak construction? 

<koosvander.DeleteThis@gmail.com> wrote:

> What are the relative merits of polyester resin vs epoxy resin?

Trying to compare polyester and woven roving to epoxy and knitted
glass is like trying to compare oranges and apples.

Both are "fiberglass" laminates, but the similarity ends there.

About the best you get is 35%glass/65%resin using woven roving, mat,
and polyester.

OTOH, it is quite common to get a 50%glass/50%resin using knitted
glass and epoxy. This laminate does not require any mat.

Bottom line....................

Polyester/roving produces a rather brittle, heavy laminate.

Epoxy/knitted glass produces a more ductile, lighter weight laminate.

Pound for pound, polyester and woven roving cost less per pound, but
you use more pounds, so the cost differences tend to disappear.

Epoxy, knitted glass and a 1/2" Airex foam core would produce a very
light weight, bullet proof, dinghy or kayak.

Just remember three things.

1)You will buy a commercial dinghy for less money than you will spend
to build one.

2)You build one because you want to do it.

3)Once you use epoxy and knitted glass, you will never consider
polyester again.

Lew
 >> Stay informed about: Polyester vs Epoxy resin for dinghy/kayak construction? 

On Aug 20, 8:18 pm, "Lew Hodgett" <lewhodg....RemoveThis@earthlink.net> wrote:
>
> 3)Once you use epoxy and knitted glass, you will never consider
> polyester again.
>
> Lew


You got that right!!
 >> Stay informed about: Polyester vs Epoxy resin for dinghy/kayak construction? 

On Aug 20, 1:31 pm, koosvan....RemoveThis@gmail.com wrote:
> On Aug 20, 1:01 pm, Paul Oman <i....RemoveThis@epoxyproducts.com> wrote:
>
>
>
>
>
> > koosvan....RemoveThis@gmail.com wrote:
> > >I am planning to build a hard dodger for my sailboat. I'm fairly
> > >mechanically skilled, and accustomed to working with my hands, but
> > >have never worked with fiberglass repair/construction.
>
> > >So I'm planning to make a dinghy or kayak before I make the dodger, to
> > >gain some experience.
>
> > >So far I like the Foamee Glen-L dinghy, it's a foam and fiberglass
> > >construction, which I like because of the fair lines (good for
> > >dodger). Search the 'net for links, I'm not promoting it..
>
> > >Two questions..
>
> > >What are the relative merits of polyester resin vs epoxy resin?
>
> > >Any recommendations on other dingy plans or kayak plans which have
> > >smooth lines instead of the hard corners seen with plywood
> > >construction?
>
> > >Thanks,
> > >-Koos
>
> > Epoxy resins don't dissolve foam but I believe polyester resins do.
> > Your options would seem to be a small boat or a puddle of foam goo.
>
> > paul oman
> > progressive epoxy polymers
>
> Very good! That's helps me with that question.
>
> Anyone with suggestions on alternate plans, dinghy or kayak with
> smooth lines?
>
> Thanks,
> -Koos.- Hide quoted text -
>
> - Show quoted text -

I use this site for info on constructions methods for my outrigger
canoe project. He has a few plywood kayak designs.

http://oneoceankayaks.com/stitchglue/stitchkayaks.htm
 >> Stay informed about: Polyester vs Epoxy resin for dinghy/kayak construction? 

Lew Hodgett wrote:

snip

> 3)Once you use epoxy and knitted glass, you will never consider
> polyester again.
>
> Lew
>
>
>

Amen, brudder!
 >> Stay informed about: Polyester vs Epoxy resin for dinghy/kayak construction? 

On Aug 20, 1:01 pm, Paul Oman <i....DeleteThis@epoxyproducts.com> wrote:
> koosvan....DeleteThis@gmail.com wrote:
> >I am planning to build a hard dodger for my sailboat. I'm fairly
> >mechanically skilled, and accustomed to working with my hands, but
> >have never worked with fiberglass repair/construction.
>
> >So I'm planning to make a dinghy or kayak before I make the dodger, to
> >gain some experience.
>
> >So far I like the Foamee Glen-L dinghy, it's a foam and fiberglass
> >construction, which I like because of the fair lines (good for
> >dodger). Search the 'net for links, I'm not promoting it..
>
> >Two questions..
>
> >What are the relative merits of polyester resin vs epoxy resin?
>
> >Any recommendations on other dingy plans or kayak plans which have
> >smooth lines instead of the hard corners seen with plywood
> >construction?
>
> >Thanks,
> >-Koos
>
> Epoxy resins don't dissolve foam but I believe polyester resins do.
> Your options would seem to be a small boat or a puddle of foam goo.
>
> paul oman
> progressive epoxy polymers


Very good! That's helps me with that question.

Anyone with suggestions on alternate plans, dinghy or kayak with
smooth lines?

Thanks,
-Koos.
 >> Stay informed about: Polyester vs Epoxy resin for dinghy/kayak construction? 

<koosvander.TakeThisOut@gmail.com> wrote in message
news:1187641905.794630.57100@x40g2000prg.googlegroups.com...
> Anyone with suggestions on alternate plans, dinghy or kayak with
> smooth lines?

Ian Oughtred's Puffin?

See www.customware.nl/boats
And that one is entirely glued with epoxy.

Meindert
 >> Stay informed about: Polyester vs Epoxy resin for dinghy/kayak construction? 

> 3)Once you use epoxy and knitted glass, you will never consider
> polyester again.
>
> Lew

Thanks Lew, I have worked with epoxy before, rebuilding a hatch for my
son's 24-foot sailboat.

I don't know why I though that polyester would be an option, just
ignorance I suppose.. Thus my question..

Best wishes,
-Koos.
 >> Stay informed about: Polyester vs Epoxy resin for dinghy/kayak construction? 

On Aug 21, 1:26 am, "Meindert Sprang" <m... RemoveThis @NOJUNKcustomORSPAMware.nl>
wrote:
>
> Ian Oughtred's Puffin?
>
> Seewww.customware.nl/boats
> And that one is entirely glued with epoxy.
>
> Meindert

That's a beautiful dinghy!

Perhaps I should make one like that, for the experience. I'm doing
this as a prelude to making a hard dodger on my sailboat. It won't be
a lapstrake dodger, but perhaps the skills will be beneficial. I don't
know if I need to invest so much time into woodwork skills.. Perhaps I
do?

I really plan to make a fiberglass hard dodger and bimini, with smooth
lines, hard windows, and some wood trim.

-Koos.
 >> Stay informed about: Polyester vs Epoxy resin for dinghy/kayak construction? 

On Mon, 20 Aug 2007 19:43:45 -0000, koosvander.DeleteThis@gmail.com wrote:

>What are the relative merits of polyester resin vs epoxy resin?
I think epoxy is somewhat stronger, and kayaks are famous for hitting
rocks. For a dingy that may not matter as much. I heard epoxy costs
more, but if you end up with a lot of work in it, why end up with
something second rate.

Casady
 >> Stay informed about: Polyester vs Epoxy resin for dinghy/kayak construction? 

On Mon, 20 Aug 2007 17:18:24 -0700, "Lew Hodgett"
<lewhodgett.DeleteThis@earthlink.net> wrote:

><koosvander.DeleteThis@gmail.com> wrote:

Did you know that you seem to have posted three copies of the same
message? I don't really mind all that much, but I thought you might
like to know.

Casady
 >> Stay informed about: Polyester vs Epoxy resin for dinghy/kayak construction? 

"Richard Casady" writes:

> Did you know that you seem to have posted three copies of the same
> message?

After the fact, yes.

It was my problem.

Lew
 >> Stay informed about: Polyester vs Epoxy resin for dinghy/kayak construction?