"engsol" writes:

Now that I have a boat, I need to replace a couple of
gate valves used as seacocks.

Yep, you sure do.

Nigel Calder et all recommend using a wood block and bronze
bolts to secure the seacock to the hull, rather then simply
screwing it to the through hull. Makes sense to me.

The diagrams all show a perfectly flat hull, but as we all know,
real hulls are generally curved. My question is: what's the
best way to contour the wood block (actually a ring) to conform
to the hull? Any hints?

IMHO, forget the wood, here are a couple of alternatives.

1) Substitute standard gray filled PVC plastic for the wood, then bond to
the hull with epoxy based filler, covered with knitted glass.

(Find an industrial plastics distributor in your area and get a remnant
piece of 3/4" PVC.)

Use knitted glass and epoxy to lay up a pad for the seacock.

You don't have to be fussy about the weave since this is basically a
compression load.

Use odd ball scraps if you have any like I do.

The process will take several days since you will only be able to lay a
couple of layers of glass at a time, then wait at least 24 hours before
laying more glass.


HTH

Have fun.

Lew