Carbon fiber&fiber glass

Carbon fiber&fiber glass

Post by Trelbi » Mon, 11 Aug 1997 04:00:00


I am building a 21 ft.plywood boat,and I plan to cover it with carbon
fiber and fiber glass,is this a good idea or bad,and I plan to use carbon
fiber and fiber glass for the tanks,can someone help with this?
Thanks LB4475

 
 
 

Carbon fiber&fiber glass

Post by Jim Cha » Thu, 14 Aug 1997 04:00:00

Quote:

>I am building a 21 ft.plywood boat,and I plan to cover it with carbon
>fiber and fiber glass,is this a good idea or bad,and I plan to use carbon
>fiber and fiber glass for the tanks,can someone help with this?
>Thanks LB4475

It depends... carbon is almost certainly OTT. Glass can be beneficial,
depending on the situation, ply size etc. You might want to check out
http://www.paw.com/sail/cherub/bldwood.htm, which discusses ply
sandwich construction for a smaller - but very likely higher stressed
and much more lightly uilt - dinghy class.

Jim C

 
 
 

Carbon fiber&fiber glass

Post by craig o'donne » Sun, 17 Aug 1997 04:00:00


 >  I am building a 21 ft.plywood boat,and I plan to cover it with carbon
 >  fiber and fiber glass,is this a good idea or bad,and I plan to use carbon
 >  fiber and fiber glass for the tanks,can someone help with this?
 >  Thanks LB4475

Carbon? I hope you're rich. I've used carbon over 3mm ply on double
paddles successfully but I'd hate to pay for sheathing an entire boat in
it.

Email me and I can give you some more info and a few web links to check out.

-- COD
   craig o'donnell             |||  author of Cool Mac Sounds

   The Proa FAQ    
      <http://www.***-dyne.com/~jkohnen/proafaq.html>
   The Cheap Pages
      <http://SportToday.org/

 
 
 

Carbon fiber&fiber glass

Post by Robert Taylo » Sun, 17 Aug 1997 04:00:00


:  >  I am building a 21 ft.plywood boat,and I plan to cover it with carbon
:  >  fiber and fiber glass,is this a good idea or bad,and I plan to use carbon
:  >  fiber and fiber glass for the tanks,can someone help with this?
:  >  Thanks LB4475

   My experience with carbon fiber has been mixed,  I've never actually
   used it for a boat, usually on rc airplanes, it's tensile strength is
   incredible, but after you put epoxy on it it's sheer strength is bad.
   In other words if you pull along with the fiber it is incredibly strong
   if you pull or bend the fiber any other way it will break.  I would
   look carefully at the type of stress on the boat before adding it.  Kevlar
   reinforced fiber glass might be a better choice?  Hope this helps
                                              Robert

 
 
 

Carbon fiber&fiber glass

Post by robert sho » Mon, 18 Aug 1997 04:00:00

Carbon fiber is VERY expensive and probably an overkill for your
project.

As for tanks, buy poly tanks. They are vey light, tested & approved,
will last almost forever, are virtually bomb proof, and relatively
cheap.

I've replaced several owner built fiberglass tanks in the last couple of
years, for a variety of reasons. In addition to the problems they had,
these tanks were all extremely HEAVY.

The last job, which I just finished, involved replacing two 45 gal.
diesel fuel tanks in a coastal cruiser. It took three men, breaking
their backs, to get them out. I easily lifted the new poly tanks in
alone.

Good luck on your project.

 
 
 

Carbon fiber&fiber glass

Post by Russell Turp » Tue, 19 Aug 1997 04:00:00

-*--------

Quote:

> Kevlar with epoxy is a most excellent combination.  Wetting it out is
> absolutely no problem using System Three epoxy.  Chopped strand kevlar
> mat is quite a bit tougher to wet out. I like to wet the substrate
> before laying the mat. It assures a quicker and better wetting and
> penetration even at temps low as 65F.

While Kevlar is an expensive fiber, I am surprised it is not
more used as the outermost layer on the keel and the forward
portions of the hull below the water line, because of its
resistance to penetration and abrasion.  How many boats lost
to collision or grounding would still be afloat if they had
just one layer of Kevlar in these frequently abused portions
of the hull?  If I were building (or having built) a boat with
FRP hull, I think I would insist on this.

Russell

--
An atheist doesn't have to be someone who thinks he has a proof that
there can't be a god.  He only has to be someone who believes that
the evidence on the God question is at a similar level to the evidence
on the werewolf question.            --  John McCarthy

 
 
 

Carbon fiber&fiber glass

Post by edecke » Tue, 19 Aug 1997 04:00:00

On 16 Aug 1997 11:29:17 -0600, Robert Taylor

Quote:

>>   My experience with carbon fiber has been mixed,  I've never actually
>>   used it for a boat, usually on rc airplanes, it's tensile strength is
>>   incredible, but after you put epoxy on it it's sheer strength is bad.
>>   In other words if you pull along with the fiber it is incredibly strong
>>   if you pull or bend the fiber any other way it will break.  I would

What is your experience with woven carbon fiber?  That should produce
strength in both directions, y/n?

Quote:
>>   look carefully at the type of stress on the boat before adding it.  Kevlar
>>   reinforced fiber glass might be a better choice?  Hope this helps

Kevlar with epoxy is a most excellent combination.  Wetting it out is
absolutely no problem using System Three epoxy.  Chopped strand kevlar
mat is quite a bit tougher to wet out. I like to wet the substrate
before laying the mat. It assures a quicker and better wetting and
penetration even at temps low as 65F.
 
 
 

Carbon fiber&fiber glass

Post by Glenn Ashmor » Thu, 21 Aug 1997 04:00:00

Quote:

> -*--------

> While Kevlar is an expensive fiber, I am surprised it is not
> more used as the outermost layer on the keel and the forward
> portions of the hull below the water line, because of its
> resistance to penetration and abrasion.  How many boats lost
> to collision or grounding would still be afloat if they had
> just one layer of Kevlar in these frequently abused portions
> of the hull?  If I were building (or having built) a boat with
> FRP hull, I think I would insist on this.

        My layup schedule includes a layer of Kevlar as the second of 4
interior plys for impact resistance.  Kevlar is impact and penetration
resistant but not so good for abrasion so it should not be used as an
exposed ply.

        Glenn