Ok for "stripper" construction :-)
Substance is the same.
We have not yet an acceptable italian translation ;-).

Centerboard slot and deck stepped mast are always risk areas, where loads
are very high.
That's true on every small sailboat, specially in homebuilding, whichever
material or technique You use.

As You know, Polyester has not high adhesive properties on wood.
In the the early 1980's there was a low knowledge of epoxies.
Now the risks of crash, leaking or delamination are a bit reduced

Ciao
Leo

"William R. Watt" wrote :

people used to use the term "strip planking" to describe what you are
planning but now its used more widely for any very narrow planks, like the
thin planks used on canoes and kayaks, called "stripper" construction.

I owned a boat much like what you are describing, 3/4 x 3/4 "mahogany"
(probably luaun) strips, sheathed in fibreglass cloth and polyester resin,
21 ft long, moulded fibreglass deck and cabin. I bought it used. I didn't
trust my sailing ability enough to buy a new boat. I tried to estimate the
dispalcement from lookign at the waterline adn got about 1200 lb but
that's suspect. It had a flat steel plate centreboard weighing 75 lb. It
was not built to sail but to be used as a plug for a mould for a class of
fibreglass sailboats but the fibreglass prototype was too heavy and they
gave it up. too bad they did not do their calaclutions before wasting all
the time and money. the plug made a lovely light dispalcement sailboat and
of course the hull was faired to perfection.

This boat was a bit too lightly built and had stress lines in the hull
from bow sheer to the base of the mast support and the same to stern. It
leaked at the centerboard slot and that also might have been due to the
compressive forces on the mast not being routed properly. But then all
wooden centerboard boats leak, don't they? The mast pushed down and the
shrouds pulled up and it was too much for the light hull. I don't think it
altered the shape of the boat, and I don't know if it weakened the hull,
but
the stress lines in the wooden hull were plain to see.

The choice of wood was fine. I can't claim any expertise but I do think
I'd favour the 3/4" strips and I'd check the routing of those compressive
forces the mast and shrouds transfer to the hull. The hull had been
bleached on the outside before the polyester resin was put on giving it a
light colour. The polyester bond was fine except where the water leaked at
the centreboard and the polyester was coming away. I had the loose
skin cut away, the slot sealed, and new polyester put on. The slot
actually stopped leaking for one whole season.

I had it in the early 1980's. It was my first sailboat. It was old and
cheap, mostly because nobody wanted a wooden boat. I knew nothing about
boatbuilding at the time. I had to replace one small piece of plank where
some Sunday sailor in a Laser II rammed his solid fibreglass bow into it.
(I was on starboard, he was on port, but I doubt he knew the difference
let alone the rules of the road.) I can't recall very well what I saw when
making that small repair, but I think the planks were edge nailed with no
adhesive or bedding between planks.

I liked the boat. I'd buy another strip planked boat.



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"Leo" wrote:
"Paolo Zini" wrote:

exist one organization for paulonia wood promotion
also in Italy.... You can try a googgle search....

http://www.paulownia.it/
Thank You Paolo,
I will contact them

I received a reply from paulownia.it.
Mechanical properties of this wood are very good, really comparable with
the best Red Cedar.
There are large areas of new platations in growing, mostly in the North
Italy plans, but not yet considerable productions.
Price is still too high: 800-1000 Euro / cube meter.
We have to wait for some (few) years.

Ciao
Leo

In article ,
Leo wrote:

I know cedar is better: lighter and more durable .
In Italy (I think so in all the Europe) western red cedar is 1,200 Euro x
cube meter (sorry, metric, but ratio is the same), much more expensive than
Okoumè.

Western Red Cedar is 2800EUR a cubic meter in Finland, also in Europe.


Sakari Aaltonen

"Sakari Aaltonen" wrote:

In Italy (I think so in all the Europe) western red cedar is
1,200 Euro x cube meter (sorry, metric, but ratio is the
same), much more expensive than Okoumè.

Western Red Cedar is 2800EUR a cubic meter in Finland, also in Europe.

So we are lucky to pay only 1200euro here :-((
Which wood do You use? Spruce Fir?

Ciao
Leo

In article , Leo wrote:

So we are lucky to pay only 1200euro here :-((
Which wood do You use? Spruce Fir?

Spruce/fir would be light, but what I see is very knotty. Pine is heavy.
I think some people use aspen. (Me, I haven't done any strip planking,
but would like to try it some time, just out of curiosity.)

As regards the price of wood, its importance obviously depends on the
size of the boat - on a small boat, you might not save much by using
a cheaper wood. I think strip planking also needs a lot of glue, which
is not free.


Sakari Aaltonen

I received a reply from paulownia.it.
Mechanical properties of this wood are very good, really comparable with
the best Red Cedar.
There are large areas of new platations in growing, mostly in the North
Italy plans, but not yet considerable productions.
Price is still too high: 800-1000 Euro / cube meter.

1000 euro for what? green wood, plank or strips? It would be different...
Anyway 1000 euro/cube meter is interesting...
Last year, I was evaluating Woods designs and I have requested the price for
WRC, planks to be cut in strips, and it was higher... and I was forced to go
the extreme north or to extreme south of Italy to find some WRC.
For a cat similar to the one that I am building (cat 254 from Fisher) 1 M^3
of wood is more than enough for hulls, if memory helps...
I would gather more info...
A comment... Designs like Dudley Dix radius chine, can be built using strip
planking for the chine sections, in place of cold molded panels... You
agree? :-)

Paolo

"Leo" ) writes:
"Sakari Aaltonen" wrote:

In Italy (I think so in all the Europe) western red cedar is
1,200 Euro x cube meter (sorry, metric, but ratio is the
same), much more expensive than Okoumè.

Western Red Cedar is 2800EUR a cubic meter in Finland, also in Europe.

So we are lucky to pay only 1200euro here :-((
Which wood do You use? Spruce Fir?

European Common Market?

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"Paolo Zini" wrote:

Price is still too high: 800-1000 Euro / cube meter.

1000 euro for what? green wood, plank or strips? It would be different...
Anyway 1000 euro/cube meter is interesting...

Price is for planks.
I wish it will reduce dramatically in few years ;-)

Last year, I was evaluating Woods designs and I have requested the price
for WRC, planks to be cut in strips, and it was higher... and I was
forced
to go the extreme north or to extreme south of Italy to find some WRC.

I did not find any merchant with WRC in stock, in South Italy
Could'You send me their address in private, if You have still them ?
You know, for my costumers ;-) (leave "s" from nautikits dot com).

For a cat similar to the one that I am building (cat 254 from Fisher)
1 M^3 of wood is more than enough for hulls, if memory helps...
I would gather more info...

Yes, almost two boats ;-)
If You like, I will send You the pouwlonia.it reply in attachment (about
600Kb with a .pdf document).

A comment... Designs like Dudley Dix radius chine, can be built using
strip planking for the chine sections, in place of cold molded panels...
You agree? :-)

Maybe for the larger boats like the Didi 40cr.
I should ask Dudley ( who is moving his office to U.S.A. in these days).
But I think Radius Chine is a very fast and simple method for plywood.
Recently Dudley drew a wood version of his fine Vickers 45AC, with a layer
of strip planking.

Ciao
Leo

if anyone's interested I found some old photos of the strip planked
sailboat I once owned and put them on my website ( see below) under "Boats"
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