wood is somewhat compressable so the thin edge will compress. however it
could also deform so when the wood dries out again the gap is larger.

it was common for boat hauled out over the winter to leak when first put
back in the water in the spring because the wood (and calking) had dried
out and opened over the winter. the boat would be left in shallow water to
soak up tight and stop leaking. it would them be bailed out and used for
the season.

there is an antique boat club near here which uses pumps in the spring to
keep the boats from sinking while they are soaking up.

"Steve" ) writes:
the boat was built, the inner plank edges were touching, the outer edges
were angled away so you can put in caulking.

Plank edges do not normally touch there is a gap that will allow for the
ultimate swelling or expansion of the plank. If the caulking cotton is
driven to tight (or you fill the seam with glue or epoxy) the plank will
'pull it's fastenings". The expanding plank has to go someplace.


--
My opinion and experience. FWIW

Steve
s/v Good Intentions




--
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Correct: hybrid solutions could cause problems.
I share your doubts about glued seams. There are some epoxies that are
sufficiently flexible but why take a chance?
Either build her as wooden boat or as a composite (fiberglassed boat).

--
Jacques
http://www.bateau.com

"Jim Conlin" wrote in message
...
However, if the planking cannot be fully encapsulated, meaning kept DRY,
then
i'd hesitate to fill seams with something firm like splines or epoxy
putty. If
the planking gets wet and tries to expand, something has to give. It
might be
frames or fastenings.
Only if the planking is of a species that doesn't swell much, might you
get away
with this.

I heard that some Scandinavian builders built carvel boats with no gap
at all, just perfect seams, no glue, no caulking. Don't know details,
it's been a while since I looked into it. I believe they were sailing
vessels, 35' and more, they were built thus to provide more hull
stiffness, amoung other things, and they didn't seap/leak at all.

Sorry, can't recall how/where I found the info. But it means there's
more than one way to skin a cat...

Here's an interesting post I found while doing a quick search to see if
I could find any more info:
http://www.rtpnet.org/robroy/baidark.../Nov/0020.html

Search "no caulking" on this page:
http://www.mastmate.com/a-f.html

Another mention:
http://personal.riverusers.com/~emkay/building2.html

Well, I haven't found the references I wanted, but that's it for now.

Rufus


Jacques Mertens wrote:

Correct: hybrid solutions could cause problems.
I share your doubts about glued seams. There are some epoxies that are
sufficiently flexible but why take a chance?
Either build her as wooden boat or as a composite (fiberglassed boat).

--
Jacques
http://www.bateau.com

"Jim Conlin" wrote in message
...

However, if the planking cannot be fully encapsulated, meaning kept DRY,

then

i'd hesitate to fill seams with something firm like splines or epoxy

putty. If

the planking gets wet and tries to expand, something has to give. It

might be

frames or fastenings.
Only if the planking is of a species that doesn't swell much, might you

get away

with this.

Hi

"Rufus" skrev i en meddelelse
news:ehJHb.158921$8y1.474281@attbi_s52...
I heard that some Scandinavian builders built carvel boats with no gap
at all, just perfect seams, no glue, no caulking. Don't know details,
it's been a while since I looked into it. I believe they were sailing
vessels, 35' and more, they were built thus to provide more hull
stiffness, amoung other things, and they didn't seap/leak at all.
Snip

Sure you need no caulking if you don't want any, ------ this was common
knowleage and there are a number of tricks to make sure the seam work tight
without caulking ;
Hammer down a long rod along the plank edge and plane away untill you reach
the bottom of the grove made by deforming the plank edge. Then when soaked
the compressed wood will swell.
Place the planking forgetting about the seam ,as long as the seam is not
wider than a router bit, when you are sure the wood stabilised router away
along the seam and glue in a wood spline.
Still these old tricks work for true wooden boats ,Im'e not sure it's worth
the efford with any ply boat, even if a routered in wood spline along a
tortured seam is there from the start within the plans ,it's proberly a very
good idea but I wonder if any box boat plans ask this, ------ case so I
would like to se the naval architect recomend from his own hands-on
experience.

P.C.
http://www.designcommunity.com/scrap...mages/2985.jpg

Hi

"Meindert Sprang" skrev i en meddelelse
...
"Scott Downey" wrote in message
...

Yes. But in a conventional carvel hull, the caulking absorbs the extra
dimension of the expanding wood.

WHAT ?????

Don't anyone in this forum have any hands-on experience ?
Caulking is done at the outher third of the seam and the seam is prepared
for caulking, ------- It's bloddy _not_ the damned caulking that make the
hull watertight when you build a cravel planked boat, as the bloody seams
are TIGHT even before the caulking is there.
Do you realy think cravel build boats are just a bunch of planks with seems
inbetween that you look right thru , and that you just forget about the
craftmanship as you just Bang in caulking ???
Well that's _not_ how you build a cravel planked boat hull ------- and be
glad for that, as if this was how, no craftmanship or respect for the crafts
would survive the sailers counting on boatbuilders having the knowleage to
make a safe vessel.
Just becaurse you as amature builder, seen an old mistreated hull, with
inverts opened seams, do damn'ed not mean that this sort of bad
craftmanship, was what made these beautifull vessels ------ all it mean is,
that some ignorant Amature been doing a temp. repair, where a profesional
would have replaced the plank. ( nice case you trust your life upon ).

Bet you even think that caulking is just about banging in stuffing untill
the whole plank is forced to destroy the seams around and above, ------ seem
like you even mix two compleatly different technikes by talking about
caulking with Lapstrake building ; YOU DO NOT CAULK A LAPSTRAKE HULL, unless
it's old and worn , unless the planks shuld have been replaced decades ago,
don't you Amature boatbuilders know the difference between Lapstrake and
Cravel ; then how the hell can you avoid to crack the plank edge if you
start caulking a Lapstrake hull -------- don't you se it, don't you even
know that you can destroy a lapstrake hull by caulking it ????

P.C.

"P.C." wrote in message
k...
Hi

"Meindert Sprang" skrev i en meddelelse
...
"Scott Downey" wrote in message
...

Yes. But in a conventional carvel hull, the caulking absorbs the extra
dimension of the expanding wood.

WHAT ?????

It is my understanding that a carvel hull has a slight bevel on each plank,
so the planks only touch at the inside of the hull. The cotton used for
caulking is then driven about halfway in the seam, in order to form a sort
of watertight 'rope' slightly indenting the planksides.

Don't anyone in this forum have any hands-on experience ?
Caulking is done at the outher third of the seam and the seam is prepared
for caulking, ------- It's bloddy _not_ the damned caulking that make the
hull watertight when you build a cravel planked boat, as the bloody seams
are TIGHT even before the caulking is there.

Mmmm, I quote from the Boatbuilding Manual from Robert Steward:
"Carvel planking is usually made with the seams tight on the inside and open
on the outside to receive the cotton caulking, which makes the planking
watertight".

Bet you even think that caulking is just about banging in stuffing untill
the whole plank is forced to destroy the seams around and above, ------
seem
like you even mix two compleatly different technikes by talking about
caulking with Lapstrake building ; YOU DO NOT CAULK A LAPSTRAKE HULL,
unless
it's old and worn , unless the planks shuld have been replaced decades
ago,

Ehhrr, where exaclty was I referring to lapstake construction?

don't you Amature boatbuilders know the difference between Lapstrake and
Cravel ; then how the hell can you avoid to crack the plank edge if you
start caulking a Lapstrake hull -------- don't you se it, don't you even
know that you can destroy a lapstrake hull by caulking it ????

Well, at a boatbuilding school here in the Netherlands they build clinker
lapstrake hulls and they do put sikaflex between the strakes for caulking.
Nothing is destroyed by that.

Geez Per, why on earth ary you reacting so offensive????

Meindert