wrote in message
oups.com...
Thanks for the prompt response and the really helpful information, I'm
totally new to this whole area sp please excuse any seemingly stupid
questions.
I intended to use the the epoxy as the assembly adhesive alright but I
have to ask why I have to wash and sand before laying the primer onto
the Epoxy? I'm not sure if the primer I was sold will bond well to the
epoxy I got but I'll do some other research besides on this. When all
is done and if I do apply the UV varnish ontop of the topcoat, how long
should the whole Water Wheel last before maintenance is required? Also,
is Marine Plywood the correct material to be using for this type of
product or could you recommend any better materials?

Again, the information you have provided me is invaluable, thanks.

As I said, epoxy develops a waxy film called amine blush on the surface as
it cures that limits the bond with the next coat, what ever it is. Amine is
water soluable so it can be washed off. Sanding without washing just grinds
the amine into the surface. Sanding also gives the surface some tooth for a
better mechanical bond.

How long a finish lasts is related to the UV exposure, heat and the
transparency of the coating. A clear coat boat finish in the tropics might
get a year before a new top coat is required. A good quality marine paint
might last 3 or 4 years or longer. Further north you can probably expect
twice that. What usually happens is that the pigments start bleaching and
paint surfaces start chalking up long before the coating looses its
protective ability. That might actually add a nice patina to the wheels
over time. Cracking and flaking would be a problem though.

In your case marine plywood might be overkill. The main advantage of marine
grade over a good A/B exterior grade is that it has thinner plys and
(theoretically) no voids. It will bend more evenly and if it soaks in water
it will not develop pockets of moisture that can cause interior rotting.
Your designs don't seem to use many bent shapes and as they are largely
ornamental, don't seem to be constantly immersed and won't have the long
term soaking problem.

One thing you might consider is trying solid cypress. It is relatively
cheap, very durable, requires no finish and weathers to a beautiful silver.
Definitely will look more authentic for the real traditionalist.

--
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