He's washing the inside and if anything the raw polyester is even more
porous than gelcoat. That's why I recomended the fans and lengthy drying
time. But it's important that he get a really clean surface to bond the new
glass and stringers too.

But I would not worry about pressure washing the exterior. The extremely
short period of pressurized water is not going to cause any noticable amount
of water to be absorbed. It's sitting in water for years that does that.

"Harry Krause" wrote in message
...
JamesgangNC wrote:
A pressure washer is a good idea. I'd try to spray it down well with
some degreaser first too. When I did what you're doing I also put a
bunch of cheap fans on everything for a couple weeks to make sure I had
drawn out all the moisture before I started the new glass work. Are you
replacing the stringers with wood again? I was able to make stringers
from that new composite deck material. I also left the foam out and
added drain holes. You have my sympathies, replacing wood in a fiberglass
boat was about the most underestimated home project I ever undertook.

"JR North" wrote in message
...
A pressure washer will remove the mildew/mold which looks black and
dingy.
JR

Steve Lortie wrote:
I am just about done putting in a new transom and moving on to the
stringers. The hull/old glass roven that I will be bonding the new
roven to
is extremely dirty looking, mostly black from years of being wet I
think.
What is the best way to get it as clean as possible for bonding the new
stuff to. Is sanding the only thing to do? Has anyone used TSP for boat
cleaning, paint preping etc?

Thanks



I've never used a pressure washer on any of my boats. Perhaps it is just
an old wives' tale, but someone my foggy brain internalized the idea that
a pressure washer would force water through the gelcoat and compromise it
and wet down the fiberglass underneath.

I don't know whether there is a lick of truth to this belief, but I do
know that gel coat is porous, and that water under high pressure can
certainly push its way through a membrane and that is all gel coat really
is.

Or am I inhaling too much smoke from that burning manilla rope?