Cold Molded Wylie 38 - Wet Wood

[Bowdrie]

Many times the process of drilling a bazillion holes and filling them with epoxy has the effect of simply putting a bunch of "epoxy nails" into bad wood.
Originally the term "WEST" was used as an acronym for "Wood Epoxy Saturation Technique".
That has long been discarded.
Epoxy applied to wood, (especially hard woods,) does NOT "saturate" beyond the first layer of unbroken cell structures.
Before any holes are filled with epoxy it is much better to flood the holes with something like "Smiths" CPES, that will penetrate and create a better sub-structure for consequent epoxy application.
As such it's better to have "blind" holes, that come close to breaking thru, but not all the way.
This keeps the CPES from simply draining thru the holes, allowing it to move laterally into the wood fibers.
Home of Smith's Original and Genuine Clear Penetrating Epoxy Sealer

[bailsout]

That’s why I mentioned taping and the drilling goes way faster unless you have a nice drill bit stop. And Smiths is my first choice.

[Jim Cate]

Originally Posted by luckylinda

Glassing a WEST strip planked hull is a mistake.

Our 32 year old strip planked hull is glassed inside and out. It has survived unscathed through all that time and ~140,000 miles of cruising with that "mistake" in execution.

Jim

[pcmm]

Originally Posted by Jim Cate

Our 32 year old strip planked hull is glassed inside and out. It has survived unscathed through all that time and ~140,000 miles of cruising with that "mistake" in execution.

Jim

I'm speculating, but I think "LuckyLinda" doesn't understand that glassing the hull inside and out is an integral component of the WEST technique!!!

[Clivevon]

Originally Posted by pcmm

I'm speculating, but I think "LuckyLinda" doesn't understand that glassing the hull inside and out is an integral component of the WEST technique!!!

Interesting. I have seen strip planked & epoxied boats where the wood was clearly visible as a feature inside & out. Are you talking about a transparent layer of cloth, or something else on the boat?

[pcmm]

Originally Posted by Clivevon

Interesting. I have seen strip planked & epoxied boats where the wood was clearly visible as a feature inside & out. Are you talking about a transparent layer of cloth, or something else on the boat?

Glassed wood with epoxy and cloth is very transparent. Cedar strip canoes are glassed

[Clivevon]

Originally Posted by pcmm

Glassed wood with epoxy and cloth is very transparent. Cedar strip canoes are glassed

Thanks - it would be a shame to hide the wooden hull.

[Apollo19.5]

Originally Posted by pcmm

Glassed wood with epoxy and cloth is very transparent. Cedar strip canoes are glassed

We have built several similar. One yacht, one rowing skull and one Canadian canoe. All built with strip planked WRC and glassed both sides using WEST system. All very strong, light and durable. The skull and canoe were left clear. The yacht was painted outside and left clear inside showing the stripped timber.

[Jim Cate]

The yacht was painted outside and left clear inside showing the stripped timber.

As is ours. Epoxy is not very resistant to UV, so painting any hull that is left in the water (and sun) is usually painted to protect the epoxy from degradation... and the glass over ply decks too. The glass on the underwater portion of the hull gives protection from worm as well.

Jim

[NRosenthal]

clasount,
I'd like to give you a bit of first hand advice. I owned a 1986 Tom Wylie 45' cold molded boat for 19 years. The build of my former boat is almost identical to yours. You now own a great boat that can take care of you for many years, but you need to take care of you issues, and you really want to do this right. Sadly, most of the advice you have been given on this forum is ....well its wrong. Now the Kate's own a modern strip plank boat and I take both Kate's for their opinion but you have a Wylie Cold Molded boat ant it's unique. Most of the rest is sh t. You have rot, it need to come out! I think you deck in that area of your boat is done but it will need to come out anyway, to address the shear and beam, so no worries. I would rather not to keep my sugestions in the forum, so contact me directly if you like. BTW I have e copies of my boats blueprints which might help. Oh, please DON'T drill holes in your hull, PLEASE!

[clausont]

Originally Posted by Clivevon

Are you sure its epoxy coated, not epoxy saturated?
Gougeon Bros WEST stands for wood epoxy saturation technique. Used on strip planked construction. Each plank epoxied to next one. You might find that wet unsaturated patches of wood are not connected to each other but are isolated by epoxy saturated wood so need drying out separately. Multiple moisture readings, multiple drain holes & vacuum bagging larger area sounds like a good idea.

You are correct - it is epoxy saturated. That is what I am hoping to find - each strip of wood isolated from the next by the epoxy barrier between them. Thanks

[Jim Cate]

OP, I find that I'm a bit confused. You said:
"It is a strip planked hull - cold molded. (think Gougeon Brothers)"

Most of your description tallies with strip planking, so where does the cold molding come in? that term usually means laying up several layers of diagonal strips (perhaps 100 mm wide and less than ~6mm thick) following the curves of the hull from gunnel to keel, with epoxy bonding the layers together. I believe that Joel White's yard does a combination of strip planking covered with a diagonal veneer layer on the outside... is that what you mean in your hull?

Both are wonderful means of building a one-off yacht, and I'm sorry that yours has suffered from the dread rot.

Jim

[Fore and Aft]

Jim we built a strip plank yacht in NZ with a diagonal layer of timber on the outside. The boss was just trying to stop the strip planks becoming visible later in the boats life. There's so many ways to build a strip plank yacht. Personally I like to see them glassed inside and outside.
Cheers

[Bowdrie]

Originally Posted by Jim Cate

OP, I find that I'm a bit confused. You said:
"It is a strip planked hull - cold molded. (think Gougeon Brothers)"

Most of your description tallies with strip planking, so where does the cold molding come in? that term usually means laying up several layers of diagonal strips (perhaps 100 mm wide and less than ~6mm thick) following the curves of the hull from gunnel to keel, with epoxy bonding the layers together. I believe that Joel White's yard does a combination of strip planking covered with a diagonal veneer layer on the outside... is that what you mean in your hull?
Jim

Technically you are correct. Strip planking is (drum roll,) "strip planking".
With Cold Molding you are basically making the hull out of "Home made Plywood", except using epoxy.
In the "old" days they made small boats, (Dinghy,) by "Hot Molding", using thermosetting glue and autoclaves.
Various techniques for strip planking include using "hollow & round" shaped strips, or using square-edged strips, or making strips with a "running bevel".
Each has pros/cons, using square-edged stock cuts building time but requires more epoxy and doesn't give the "seamless" look either inside or outside.
The "hollow & round" way is commonly used for building a plug to make a mold from, goes fairly fast but still requires good fairing work.
The best looking, (especially on an inside left unpainted,) uses running bevels. The time/labor goes up for initial construction, but fairing time is reduced.
It was/is common for the strips to be edge fastened with bronze nails, a more recent way is using dowels set with epoxy.
No matter the method, "stealers" need to be fitted at various places to accommodate the changes in hull girth.
For equal hull thickness cold molding gives better torsional strength, but it's VERY labor intensive, and requires immense quantities of an expensive product and a lot of time consuming fairing work.
Using the two methods together, (you mentioned Joel White,) gives a nice continuous visual feel inside with the diagonal outside adding torsional strength, and overall labor/wood/epoxy costs are lessened.
Anyway you do it you can get a really fine strong monocoque structure that is far more rigid than any "normal build" fiberglass hull, and a lot "warmer" inside.

[Jim Cate]

^^^
Good summary of techniques here. Our hull is constructed of 25x25mm strips, coved (or as you described "hollow and round") epoxied and edge nailed. After all her years folks are still convinced that she's FRP from a mold. I'm a bit miffed by that, for she is fairer than many FRP boats!

At any rate, it is a great construction method and worthy of discussion, but we're not helping the OP with his issues, so I'll back out and make room for folks who can.

Jim