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Tosk

In article ,
says...

On Tue, 3 Nov 2009 17:33:12 -0700, "SteveB"
wrote:

Questions: Can I steam and bend a piece of cut plywood to go across the bow
portion of my boat, or will the steaming cause delaminating?

Probably not your best option. Plywood can be bought in thicknesses
down to 1/64". A glued-up lamination of thin sections of plywood would
accomplish your goal and make splitting or delamination (which I
suspect is very likely) a non-event.

3/4 inch is gonna' be tough depending on how much of a bend you need. I
would suggest like Gene said, only use 1/4 inch thickness. Now, because
it lacks voids, you would have a better chance with marine or Occoume
plywood. If you wish to try to bend it, a real steam bend would be
tough. You need constant steam for iirc 15 minutes per quarter inch and
that is not easy unless you have a real steamer and closed box. Plywood
is tough to steam even with that as it's hard to get consistent steam
around the whole surface. Once wood gets soft from steam, even a few
seconds break in the steam will cause the cell walls to set, and they
can not be re-softened, it only happens once. My suggestion is to use
heat and moisture without steaming. Boil some blankets and lay them over
the wood hot and wet and try to bend it slowly like that, without ever
actually softening the cell walls within the wood.

All that being said, I would try the hot blanket first, plywood does
bend ok, sometimes I use a Spanish windlass and bend it over a period of
days or in the case of 2x6's weeks. If that doesn't work, try three
thicknesses of 1/4 inch. Just my $0.02.

Another better source of info might be rec.boats.builders..

Good luck, Scotty from Smallboats.com aka Tosk...

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