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

"Brian Nystrom" wrote in message
...
MMC wrote:

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.

MMC wrote:
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.

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.

On Tue, 27 Jul 2004 16:06:02 GMT, "MMC" wrote:

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

"Brian Nystrom" wrote in message
...
MMC wrote:

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.

Brian and Pete,
Thanks for the good answers. I'm trying to learn something here too.
MMC
"Pete C" wrote in message
...
On Tue, 27 Jul 2004 16:06:02 GMT, "MMC" wrote:

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

"Brian Nystrom" wrote in message
...
MMC wrote:

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.