Andy,

My personal preference is to use EPOXY, rather then the poly. While it does
cost more {actually not so bad when you buy in quantity . . . and not at
your local 'marine store'. 3-gallon 'kits' of RAKA cost about $100, with
shipping}, your concern becomes a 'non-issue'.

From your description, this will be a 'one-time' build and you have a lot of
intentions for the boat. Most builders & designers say that the actual hull
ply is the smallest portion of the total cost, and one shouldn't skimp on
it. You have already decided to save money with your choice of 'substrate',
now think of balancing the equation. The sheathing & resin is the actual
INTERFACE between you and the 'deep blue'. I do have experience with Lauan
as a substrate . . . and the customer's hull was still solid as rock after a
rough 7-years. {exterior sheathed, interior only painted}

While I don't detect any odor from cured epoxy, there is only a mild one
when it is being mixed. For ease of application, in the beginning as well as
later assembly stages, I 'paint' the entire sheet with an initial coat of
epoxy. I may even thin it a bit for increased absorption. Then parts are
lofted, or laid out from templates, and the sheets cut. After trimming to
final size, the edges are sealed with epoxy.

I happen to like a 'hot' 5-to-1 formulation hardener. What I like about the
RAKA Brand is that the 'kits' are based on 'quart volumes' . . . I can order
2 gallons of Resin and 4 quarts of Hardener - a couple of the 'fast' 5-to-1,
one of the 'slow' 2-to 1, and one of the others available. This allows me to
'custom mix' a batch depending on the particular project, what I expect the
material to do, and the environmental conditions. I find POLY to be
'brittle'. The 5-1 epoxy formulations are 'hard' compared to the 2-1 and 3-1
mixes. THOSE tend to be more 'flexible - which would directly apply to your
concern {although as I stated, to me it is a non-issue}.

Do some research, then do what ever YOU are most comfortable with. Just make
sure you have PHYSICAL ACCESS to every compartment. Screw lids, tops, sides,
etc., on but don't glue them shut. That way they can be occasionally
inspected, ventilated, and repaired or repainted.

Regards & Good Luck,
Ron Magen
Backyard Boatshop

"Andrew Butchart" wrote in message
. ..
SNIP - a Stevenson's Weekender -
SNIP - The sides will be 1/4" luan coated with polyester resin (no
fiberglass on the inside).
I'll fiberglass the outside after assembly.

My concern is whether the resin will be able to take the bending after it
sets up, or will it crack?

SNIP -
--
Andrew Butchart