sheating dillema

[wernhuy]

read the answers concerning sheating a wooden boat ...


I am not an expert that is the reason why I listen to advice

let me give a choice of advices and contradictions I got and read

polyester is porousnon adecive, thus underlying wood rots
epoxy is non porous and stronger and more expensive

only reason to sheat a wooden boat is to prevent excessive movement -leaking due to thin planks.It is an alternative to complete replanking
(Some say even rot can be penetrated with epoxy and cured)
-one layer of cloth is enough can even be varnished ?- don't... do use at least two layers or more and paint in a light, sun reflective colour


what then ?? epoxy sheating some say it is possible even as a longterm sollution
-No problem since new boats like strip builds are encapsulated in epoxy glass or cloth????
-do not sheat : a minor leak will go unnoticed , will and shall bring maximum rot.

a wooden boat hull is flexible , but not after beeing sheated.So the hull has to be in good condition and and everything (re)fastened.

first you will have to spline and glue between the planks ( carvell build) to stiffen up the hull.
the wood has to be completly very dry.
The inside oft he hull has to be sealed with epoxy so no water or damp will penetrate. swelling planks under epoxy will crack open the hull and frames

-it is better to wood-laminate the hull with three or two cross layers but this has more risc for air trapped between the layers and consequently infiltration rot.

-do not sheat-you can better only spline the planks.
4/8" plank thickness (orginally 5/8" )is more than enough.-if you spline you must use softwood splines.
splining will... / will not... work on a hardwood (mahogany) planked boat ;old hardwood will chrush no more thus the frames will crack after splining evevwith softwood. You can not leave the boat in the water all year.


You must only clean up between the planks to glue thin splines in to fill the gap
you must use splines at least 6 mm thick
do .../do not.... glue them to the both planks just one side so movement is still possible.

I realy would like to know what modern hull repair -restoration method is just good and pratical.

Perhaps some boats can only be saved with "modern" methods and of course these will not be prefered over the classic methods but it is in some cases the only sollution
Ofcourse how many classic yachts are almost complete rebuilds; reframed replanked redecked rerigged.

regards,

werner

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[ccscott49]

Now then. Splining a wooden boat is normally done when the boat is built, doing it later is time consuming expensive and probably not worth the effort, splined boats are normally designed and built that way. Epoxy wood composite, are designed that way, the strips are thin and of a porous wood softish wood, (cedar) the "planks" are specifically cut and shaped to make this procedure work. Sheathing an old hull in epoxy or polyester and cloth, is a quick fix, all the wood has to be in excellent condition, or any rot in the wood will develope further, it also has to be all at the same moisture content, basically impossible with an old boat. If you want to repair an old wooden boat, repair it with wood, preferably the wood it was built with, all this to sheath or not to sheath is basicallly a load of tommy rot, do the job prperly or dont bother doing it at all. A wooden boat was built with the materials available at the time, we can use more modern glues etc, but remember it was also designed with the technology of the time in mind, most wooden boats built well in the first place, will outlive many owners, if looked after, dont try "modern" quick fixes, they invariably dont work, I know, I've tried a bunch of them! IMHO of course.

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