Wooden boat construction

[Raggi_Thor]

Paul Gartside is discussing old fashioned strip planking with too little glass to make it a stable composite laminate. You must be sure you have a balance between the outer and the inner skin and that the glass (or carbon or kevlar) is stiffer than the wood in the transverse direction.

[Ari]

Read through what Paul Gartside wrote..O.K; In our plan of construction what important is to be able to build a good and safe boat. Don't mind much about not able to apreciate the beauty of the wood. How much epoxy is needed -minimum for 1 square feet of hull ?

[Guillermo]

Originally Posted by Raggi_Thor

....old fashioned strip planking with too little glass to make it a stable composite laminate....

What do you mean?

Ari,
What's the size of the boat you are planning to build?

[Ari]

We are looking into ways to produce fisherman boat in the range of 40 to 100 feet without utilising hard wood from our tropical jungle..O.K I'am actually not against harversting all those timber.. only the price had shoot up to a level where it is no more economical to built new fisherman boat with those timber.. previously there is still some tricle in from Indonesia..now that sources had dried up..maybe it is not worth the value to try when you might be at the receiving end of the Oerlikon and Bofors..so the supply dried up..
At the moment our country haversted stock might last a few more years..We planned to be establish into the market in the next 3 years..Those boat will be in the range of 40 feet to 100 feet long, 20 to 70 ton boat. For the pleasure craft it will be in the 20 to 40 feet long boat.

[Raggi_Thor]

Originally Posted by Guillermo

What do you mean?

Sorry if I was rude in my comments, here is what I mean,

The problems mentioned with strip planking refer to thick skins of strips with nothing to stabilize the wood in the transverse direction. You get the same problems as with glued carvel. Frames may brake when the strip skin get wet and starts to expand. Paul Gartside is quite clear about this as he writes that he will not use glass on both sides. I assume that he will use a thin glass cloth, mostly to protect against scratching. He also writes that cold molding is a better solution because the wood then is stabilized.

I think it's a common misunderstanding that wood will expand with a great force when it gets wet. The force is really quite small transversely to the fibres.

I see several ways to use strip planking without any (of these) problems,
1) A relative thin core of strips with a relative heavy layer of glass on both sides.
2) Glass on the outside and (many) laminated frames on the inside.
3) Two or three layers of wood veneers on the outside, frames or glass or veneers on the inside.

The point is that the two skins on both sides of the strip core must be equally strong and stiff enough to keep the whole laminate stable.

[Ari]

Thank you guys..your feed back and comments are very much appreciated. I had mention earlier that I had no experience in any boat building , my own uncle do actually own and operated a boat yard.He is very old now..the technology used are..what he inherited from his guru..slightly older than him.. the younger generation would like to make a change..(my children 17-18 yrs old) I'am their mentor..who know nuts about boat construction. What ever the advise and comments received here is very valuable for me to chart them into the right direction. Don't worry..I love all the comments and arguments..!

[Raggi_Thor]

Ari, you could have a look at MacNaughton's scantling rules.
http://www.macnaughtongroup.com/publishingown.htm

[Ari]

Thank you Raggi Thor.

[Guillermo]

I do not recommend striplanking for 40' + boats. For professional fishing boats we are using over sized wbp cold molded skins over traditional sawn wood structures with quite good results.