Epoxy fairing compound and glassing hull

Epoxy fairing compound and glassing hull

Post by Ron Whit » Wed, 28 Jul 2004 02:05:12


I am helping a friend who is building a 35' motor trawler. It is planked
with marine ply and epoxy glued and it soon need fairing. Are there any
good commercially available epoxy fairing compounds in 5 gallon units?   He
is debating weather to fair the hull after the glass is laid or more likely
fairing before and lightly fairing after the glassing.
On the subject of glassing, the designer, Carl  Stambaugh, recommended
biaxial tape at the corners and  has left skin up to the builder and has
offered several suggestions. I am thinking that maybe a biaxial covering
would be easier for a small crew (2) to handle as compared to woven cloth?
The boat has a 2' wide box keel that among other things, will take most of
the grounding abuse. He is debating on the glass skin with a Kevlar overlay
or just add some roving to the bottom of the box for protection. Any
suggestions would be welcome.

--
Ron White
my boatbuilding web site is:
www.concentric.net/~knotreel

 
 
 

Epoxy fairing compound and glassing hull

Post by Jim Conli » Wed, 28 Jul 2004 07:20:48

Depending on the nature of the stitching that holds it together, it can be
harder to get a smoooth surface on biax.

System Three has an epoxy fairing compound in bucket quantities.  It cures
quickly.  To me, it looked expensive, but it might save enough labor to be
worth it.

Quote:

> I am helping a friend who is building a 35' motor trawler. It is planked
> with marine ply and epoxy glued and it soon need fairing. Are there any
> good commercially available epoxy fairing compounds in 5 gallon units?   He
> is debating weather to fair the hull after the glass is laid or more likely
> fairing before and lightly fairing after the glassing.
> On the subject of glassing, the designer, Carl  Stambaugh, recommended
> biaxial tape at the corners and  has left skin up to the builder and has
> offered several suggestions. I am thinking that maybe a biaxial covering
> would be easier for a small crew (2) to handle as compared to woven cloth?
> The boat has a 2' wide box keel that among other things, will take most of
> the grounding abuse. He is debating on the glass skin with a Kevlar overlay
> or just add some roving to the bottom of the box for protection. Any
> suggestions would be welcome.

> --
> Ron White
> my boatbuilding web site is:
> www.concentric.net/~knotreel


 
 
 

Epoxy fairing compound and glassing hull

Post by MMC » Wed, 28 Jul 2004 07:41:00

Jim,
If these guys are fairing before laying up with epoxy, can't they use poly
or vinylester resin with fairing filler or micro balloons? It'd be a lot
cheaper.
MMC

Quote:
> Depending on the nature of the stitching that holds it together, it can be
> harder to get a smoooth surface on biax.

> System Three has an epoxy fairing compound in bucket quantities.  It cures
> quickly.  To me, it looked expensive, but it might save enough labor to be
> worth it.


> > I am helping a friend who is building a 35' motor trawler. It is planked
> > with marine ply and epoxy glued and it soon need fairing. Are there any
> > good commercially available epoxy fairing compounds in 5 gallon units?
He
> > is debating weather to fair the hull after the glass is laid or more
likely
> > fairing before and lightly fairing after the glassing.
> > On the subject of glassing, the designer, Carl  Stambaugh, recommended
> > biaxial tape at the corners and  has left skin up to the builder and has
> > offered several suggestions. I am thinking that maybe a biaxial covering
> > would be easier for a small crew (2) to handle as compared to woven
cloth?
> > The boat has a 2' wide box keel that among other things, will take most
of
> > the grounding abuse. He is debating on the glass skin with a Kevlar
overlay
> > or just add some roving to the bottom of the box for protection. Any
> > suggestions would be welcome.

> > --
> > Ron White
> > my boatbuilding web site is:
> > www.concentric.net/~knotreel


 
 
 

Epoxy fairing compound and glassing hull

Post by Glenn Ashmor » Wed, 28 Jul 2004 10:30:05

Tape the joints first. Biax tape will be about a 32nd high and is a real
PITA to fair level with the rest of  the panel but it is needed for
strength so put up with it.  Do your rough fairing before laying the
glass and then skim coat for final fairing. You can make a very good
fairing putty a lot cheaper than the pre-made stuff with equal parts
epoxy resin and microballoons and enough cabosil to get the right
stiffness.

Wet woven cloth is a LOT easier to handle than wet Biax.  45/45 biax is
very unstable and will stretch in length and get narrow as you handle
it.  Dry layup byax is a little more stable but you still have to be
careful not to stretch it out of shape.

I used the Tom Sawyer approach and got a bunch of volunteers.  One
person mixing resin, two people wetting out and 3 people laying.  We did
two layers of DB170 biax and one 6 oz. woven on my 45' hull in 6 hours.
  After wetting out on a table made from a couple of sheets of melamine
we rolled the biax on 2" PVC pipe to carry it to the boat.  The only
significant increase in cost was a couple of cases of beer when we
finished.

Quote:

> I am helping a friend who is building a 35' motor trawler. It is planked
> with marine ply and epoxy glued and it soon need fairing. Are there any
> good commercially available epoxy fairing compounds in 5 gallon units?   He
> is debating weather to fair the hull after the glass is laid or more likely
> fairing before and lightly fairing after the glassing.
> On the subject of glassing, the designer, Carl  Stambaugh, recommended
> biaxial tape at the corners and  has left skin up to the builder and has
> offered several suggestions. I am thinking that maybe a biaxial covering
> would be easier for a small crew (2) to handle as compared to woven cloth?
> The boat has a 2' wide box keel that among other things, will take most of
> the grounding abuse. He is debating on the glass skin with a Kevlar overlay
> or just add some roving to the bottom of the box for protection. Any
> suggestions would be welcome.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at:  http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

 
 
 

Epoxy fairing compound and glassing hull

Post by Lew Hodget » Wed, 28 Jul 2004 10:38:53

Quote:
"Ron White" writes:
> I am helping a friend who is building a 35' motor trawler. It is planked
> with marine ply and epoxy glued and it soon need fairing. Are there any
> good commercially available epoxy fairing compounds in 5 gallon units?

You want to do the job cheap or do it right?

If it were my project, I'd start buying epoxy in 500 lb drums, hardner in 40
lb pails and Dic-A-Perl microballoons in 30 lb bags.

Use DB170, 17 oz double bias glass, comes in approximately 220 lb rolls.

The composites industry is going bonkers right now.

Both glass and foam are on allocation.

Don't even think about carbon fiber.

There is an outfit making 30,000 carbon fiber hockey sticks and they can't
keep up with demand.

Expect 8 wks for a roll of DB170.

If you can use vendors located in SoCal, contact me off list.

BTW, glass first, fairing last.

HTH

--
Lew

S/A: Challenge, The Bullet Proof Boat, (Under Construction in the Southland)
Visit: <http://home.earthlink.net/~lewhodgett> for Pictures

 
 
 

Epoxy fairing compound and glassing hull

Post by Brian Nystro » Wed, 28 Jul 2004 19:33:09

Quote:

> Jim,
> If these guys are fairing before laying up with epoxy, can't they use poly
> or vinylester resin with fairing filler or micro balloons? It'd be a lot
> cheaper.

Perhaps they're more interested in doing it right than doing it cheaply.
 
 
 

Epoxy fairing compound and glassing hull

Post by Jacqu » Thu, 29 Jul 2004 00:28:12

I am suprised that a good designer leaves out fiberglass
specifications on plans for a 35' trawler! Are you certain it's not
somewhere in the notes?
Anyway, here is what we would use:
- fiberglass covering on plywood, if only for protection and
resistance to abrasion: 9 oz. woven but, you could use 12 oz. biaxial
45/45 no matt and add strength to those panels. The biaxial fiber
orientation at 45/45 will complement the plywood fibers at 0-90. It
cost only a tiny little bit more, less than $ 50.00 extra for the
whole boat.
- fairing epoxy: it can not be done with Bondo type stuff. We sell a
unique product from System Three named QuickFair. It is an epoxy
fairing compound that is easy to apply, cures fast and is easy to sand
and it is not soft like WEST Microlight. See a complete description
here:
http://www.boatbuildercentral.com/products.php?id=17&Fairing
You can ask questions about application etc. on our message baord and
there, you will also read opinions and tips about fairing on epoxy:
http://bateau2.com/

Jacques from bateau.com

 
 
 

Epoxy fairing compound and glassing hull

Post by Joe » Thu, 29 Jul 2004 01:03:19

Quote:

> I am helping a friend who is building a 35' motor trawler. It is planked
> with marine ply and epoxy glued and it soon need fairing. Are there any
> good commercially available epoxy fairing compounds in 5 gallon units?   He
> is debating weather to fair the hull after the glass is laid or more likely
> fairing before and lightly fairing after the glassing.
> On the subject of glassing, the designer, Carl  Stambaugh, recommended
> biaxial tape at the corners and  has left skin up to the builder and has
> offered several suggestions. I am thinking that maybe a biaxial covering
> would be easier for a small crew (2) to handle as compared to woven cloth?
> The boat has a 2' wide box keel that among other things, will take most of
> the grounding abuse. He is debating on the glass skin with a Kevlar overlay
> or just add some roving to the bottom of the box for protection. Any
> suggestions would be welcome.

 ----------------------

For fairing that much, I would mix my own compound using microballoons
and epoxy.  It will be a lot cheaper than the System three quick fair
(which is good stuff, we sell it too).

While the biax will be stronger, it will require more fairing.  If you
need large quantities of epoxy and glass, I can give you a deal on a
"kit".

Joel
Boatbuildercentral.com

 
 
 

Epoxy fairing compound and glassing hull

Post by MMC » Thu, 29 Jul 2004 01:06:02

I posted a question on a open "discussion" group, and got a typical wise-ass
response, why am I surprised?
The question was based on the adage "epoxy over poly, but never poly over
epoxy". I don't know how well polyester or vinylester sticks to plywood, and
it was just a question.
If guys building boats or refitting old boats can afford not to budget the
funds, why bother with building or refitting? Why not just go buy the boat
they want?
MMC


Quote:

> > Jim,
> > If these guys are fairing before laying up with epoxy, can't they use
poly
> > or vinylester resin with fairing filler or micro balloons? It'd be a lot
> > cheaper.

> Perhaps they're more interested in doing it right than doing it cheaply.

 
 
 

Epoxy fairing compound and glassing hull

Post by Ron Whit » Thu, 29 Jul 2004 02:13:27

Oops, I may have stepped in it again. I think I should have said it is my
understanding that he made several suggested lay-ups leaving the final
choice to my friend, the builder. I thank you and the other's who have
offered advice.
The hull on this boat is three layers of 1/2" ply on the bottoms and two
layers of 1/2" on the sides. It seems quite stout so the glass is just a
covering, I guess.
I have never done any wet lay-ups like Glenn sugested so the idea of
handling wetted out cloth with it's tendancy to become distorted kind of
worries me just having a small lay-up crew of one or two people. I would
have thought biaxial would be easier to handle than cloth due to it's
stiching. I used all biaxial on my boat but it was stiched to mat and laid
down dry, very easy to handle.

--
Ron White
Boat building web address is
www.concentric.net/~knotreel

 
 
 

Epoxy fairing compound and glassing hull

Post by Brian Nystro » Thu, 29 Jul 2004 19:16:59

Quote:

> I posted a question on a open "discussion" group, and got a typical wise-ass
> response, why am I surprised?
> The question was based on the adage "epoxy over poly, but never poly over
> epoxy". I don't know how well polyester or vinylester sticks to plywood, and
> it was just a question.

Polyester is a poor substitute for epoxy when you're bonding to wood. It
doesn't bond nearly as well. If one were to apply epoxy over it, you'd
still have a weak bond between the wood and the filler, which would be
the weakest link in the chain, so to speak.

Quote:
> If guys building boats or refitting old boats can afford not to budget the
> funds, why bother with building or refitting? Why not just go buy the boat
> they want?

Good question.
 
 
 

Epoxy fairing compound and glassing hull

Post by Pete » Fri, 30 Jul 2004 20:19:40

Quote:

>I posted a question on a open "discussion" group, and got a typical wise-ass
>response, why am I surprised?
>The question was based on the adage "epoxy over poly, but never poly over
>epoxy". I don't know how well polyester or vinylester sticks to plywood, and
>it was just a question.

Hi,

The problem is that if the wood gets damp the polyester resin will let
go, it doesn't have the same adhesive properties of epoxy.

For sticking polyester to wood you would need a bonding agent between
them. Something like POR 15 or a moisture curing polyurethane pond
sealer might do it, a though a trial would definitely be necessary.

For small areas or $$$ projects epoxy is the way to go, but if it's a
budget project and needs a lot of resin it would be worth checking out
the above.

cheers,
Pete.

Quote:
>If guys building boats or refitting old boats can afford not to budget the
>funds, why bother with building or refitting? Why not just go buy the boat
>they want?
>MMC




>> > Jim,
>> > If these guys are fairing before laying up with epoxy, can't they use
>poly
>> > or vinylester resin with fairing filler or micro balloons? It'd be a lot
>> > cheaper.

>> Perhaps they're more interested in doing it right than doing it cheaply.

 
 
 

Epoxy fairing compound and glassing hull

Post by MMC » Fri, 30 Jul 2004 22:40:48

Brian and Pete,
Thanks for the good answers. I'm trying to learn something here too.
MMC

Quote:

> >I posted a question on a open "discussion" group, and got a typical
wise-ass
> >response, why am I surprised?
> >The question was based on the adage "epoxy over poly, but never poly over
> >epoxy". I don't know how well polyester or vinylester sticks to plywood,
and
> >it was just a question.

> Hi,

> The problem is that if the wood gets damp the polyester resin will let
> go, it doesn't have the same adhesive properties of epoxy.

> For sticking polyester to wood you would need a bonding agent between
> them. Something like POR 15 or a moisture curing polyurethane pond
> sealer might do it, a though a trial would definitely be necessary.

> For small areas or $$$ projects epoxy is the way to go, but if it's a
> budget project and needs a lot of resin it would be worth checking out
> the above.

> cheers,
> Pete.

> >If guys building boats or refitting old boats can afford not to budget
the
> >funds, why bother with building or refitting? Why not just go buy the
boat
> >they want?
> >MMC




> >> > Jim,
> >> > If these guys are fairing before laying up with epoxy, can't they use
> >poly
> >> > or vinylester resin with fairing filler or micro balloons? It'd be a
lot
> >> > cheaper.

> >> Perhaps they're more interested in doing it right than doing it
cheaply.

 
 
 

Epoxy fairing compound and glassing hull

Post by Jacqu » Fri, 30 Jul 2004 23:02:15

Quote:

> Oops, I may have stepped in it again. I think I should have said it is my
> understanding that he made several suggested lay-ups leaving the final
> choice to my friend, the builder. I thank you and the other's who have
> offered advice.
> The hull on this boat is three layers of 1/2" ply on the bottoms and two
> layers of 1/2" on the sides. It seems quite stout so the glass is just a
> covering, I guess.
> I have never done any wet lay-ups like Glenn sugested so the idea of
> handling wetted out cloth with it's tendancy to become distorted kind of
> worries me just having a small lay-up crew of one or two people. I would
> have thought biaxial would be easier to handle than cloth due to it's
> stiching. I used all biaxial on my boat but it was stiched to mat and laid
> down dry, very easy to handle.

With that kind of planking, I understand the designer's response. All
what he needs is some protection against abrasion etc. -> 9 oz. woven
would be great. Pick a fine weave: as Joel writes, it will require
less fairing and sanding.

Jacques
http://bateau.com

 
 
 

Epoxy fairing compound and glassing hull

Post by Evan Gatehous » Sat, 31 Jul 2004 14:18:52

Quote:

> I used the Tom Sawyer approach and got a bunch of volunteers.  One
> person mixing resin, two people wetting out and 3 people laying.  We did
> two layers of DB170 biax and one 6 oz. woven on my 45' hull in 6 hours.
>   After wetting out on a table made from a couple of sheets of melamine
> we rolled the biax on 2" PVC pipe to carry it to the boat.  The only
> significant increase in cost was a couple of cases of beer when we
> finished.

Glenn,

Did you ever get your home made fabric impregnator to work?

About how many yards / square meter of fabric did each 6 hour session manage
to lay up?

And how much experience did your wetting out team have?

Thanks

--
Evan Gatehouse

you'll have to rewrite my email address to get to me
ceilydh AT 3web dot net
(fools the spammers)