Hull material

[tolly]

I have for the last 12 years owned an old 52" wooden Colin Archer type sailing boat, and have now started looking for a suitable live aboard ocean crossing cat. When I look at different ads, I have so far automatically ruled out the ones of cats made of wood. This because my experience of larger wooden boats tells me that they need another kind of attention and care than for example glass fibre boats. Also the risk of rotten wood in areas hard to visually examine.
Then I started to think (happends once in a while). Wood could also mean that the core is of wood, impregnated with for example epoxi, like West System, and that would be something different. They build new cats with wooden hulls today, so they should have fixed the rotting problem, but...?
Does anyone know about what wood as hull material means? Is there a risk of rotten wood in these constructions? Are they as structural strong as the GRP?

Rolf

[noelex 77]

Dear Rolf
"Cold moulded" timber construction, when done well, is in my opinion better than a conventional fiberglass construction, but others will disagree. A backbone of timber (Often thin strips of ceddar) is sheathed in expoy and fiberglass or kevlar cloth is layered on the inside and outside. The timber becomes the core.
It is light strong and has excellent insulation. There is some risk of water causing rot in the core, but because the timber is saturated in expoy the risk is low. Many conventional fiberglass boats have their decks cored with end grain balsa and these boats seem to suffer rot in the core more frequently than cold molded timber boats. Probably because end grain balsa wicks moisture so well.
It needs to be done well however, if you see a conventional wooden vessel that has simply had layers of fiberglass added run don't walk away

[sandy daugherty]

For a one-off boat or a plug for a production series, the West System is superior. An accurate and fair hull can be layed up with minimal framing, and the resulting structure is very strong. Frequently a manufacturer will build the plug for molds in this manner, or substitute foam strips. This plug may be finished and called hull #1. But the greatest production economies occur when a number of conventional fiberglass hulls can be formed from one or a series of molds taken from this plug. Boat buyers are very conservative, meaning that the resale value of a conventional boat is far better than a custom on-off or finished plug, even though when well done by an experienced craftsman, these may be superior.

A minor point: production boats will likely have molded partitions, liners and furniture rather than stick-built items, which provides a higher level of finish, while a single builder may be getting pretty tired of working on the boat when he gets to that point. But this is not a rule.

[David M]

Unless your budget prevents it, I would stay away from wood for quite a number of reasons. Resale value, knowing what you have which relates to structural integrity and maintenance. I think there are just too many unknown variables with wood. Wood boats, unless they are really old, are generally not made by professionals who have already made a lot of boats previously.

I'm not saying wood catamarans are bad, you just know a lot less about what you have than if you picked a production catamaran where you can make an educated judgement based on other boats that came out of the same mold at around the same time.

[usa-068]

My dink is cold molded western red cedar cored, carbon and kevlar with epoxy resin. Under sail it's the fasted thing on the water. VMG and all that. Anywho, my steel ketch is the current crusing boat I own. It's a displacement hull with a hull speed of seven knots. The next cruing boat will be a 15 knots sustained offshore, modern plaining hull, made from eastern white cedar and carbon fibre. It won't lose value as David M says it will. Yes it will lose value, as any boat does.

Anywho, that's my two cents. Carbon fiber boats, with nature's best composite laminate (wood - aka a tree's rings) is a fine hull material. Red Cedar on the west coast, and eastern white here in the east, is the way to go. That is if you want to have a fast and seaworthy custom boat.

[Tnflakbait]

If a cat is "wood" it is most likely cold molded, or glass over plywood. Wood is generally lighter than an all glass layup. I would be more afraid of a balsa core boat than a cold-molded one (with regards to rot).

After the 1970's there were very few professionally built wood cats. This means they were mostly amateur builds after this time.
I have a 1964 wood cat that doesn't have rot problems, and takes about the same amount of maintenance as a plastic boat.
Wood is a great material to build boats out of, but values often are lower because people are afraid of it.

[imagine2frolic]

Imagine is cold molded, and yes there can be problems with this set up. I have found rotten wood in several places. I have also found it is a simple fix. The problem was drainage, and I am repairing everything so it drains better, or it is sealed better.

After nearly 10k miles on her under my ownership. I am very happy with her. She performs well, and in my eyes is pleasing to look at. If I were to build a boat my biggest worry would be how do lockers drain. Also I would build cold molded.

Imagine is 4mm mahogany 3 times in 3 directions over her frames, and bulkheads. I have hauled the boat 3 times, and each time the yard comments on how strong she is. 1 surveyor told me she could break icebergs. I refuse to put that statemnt to the test.............LOLOLOLOLOL

Lots of pictures in my gallery...........i2f

[Tropic Cat]

Originally Posted by tolly

I have for the last 12 years owned an old 52" wooden Colin Archer type sailing boat,

God bless a patient man!!

Originally Posted by tolly

Then I started to think (happends once in a while). Wood could also mean that the core is of wood, impregnated with for example epoxi, like West System, and that would be something different. They build new cats with wooden hulls today, so they should have fixed the rotting problem, but...? Are they as structural strong as the GRP

I would rate solid (no core) GRP hulls number 1 for piece of mind.

A West System wood hull second.

A balsa or foam cored hull last. Broker docks are full of older boats with delamination issues.