Cold Molded Wylie 38 - Wet Wood

[clausont]

Originally Posted by pcmm

Are you 100% sure there is no glass. I can see the glass in the picture provided. The deck isn't glassed but the hull sure looks glassed to me. It would be really weird for a strip planked or cold moulded hull to not be glassed. The glassing is usually done as impact protection for the wood

I won't guarantee there's no glass. But I don't see any - only the wood grain in the strip planking.

[clausont]

Originally Posted by Bowdrie

You have a boat with an interesting pedigree.
In the 1985 March/April issue of WoodenBoat magazine, (issue #63,) there is an extensive interview with Tom Wylie, "Hot Ideas for Cold Molded Boats", and pics of his own Wylie 37/38 that he used as a racer and family cruiser.
He discusses building techniques and philosophy for cold molding.
Others have already posted some good pointers/paths for successful repair of the area(s) you are concerned with.
For external repair work a router can be your friend in many ways.
Well done, a cold molded boat is incredibly strong and has the rigidity to carry high rig loads without the hull deforming/bending/wracking.
They're definitely not your Grandads "wicker basket" plank on frame boat.

The original owner told me that he had consulted carefully with Tom Wylie and a couple other marine architects (whose names I forget) while he was building this boat. From what he said, he made a couple changes in the designed rig after consulting with them on his proposed changes. The gentleman spent 13 years building this boat. It was splashed in late '94.

[clausont]

Originally Posted by 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

I just checked their website and it says they are out of CPES. They suggest an alternative product, "Since we are out of stock on the CPES, we recommend the S-1 Clear Penetrating Epoxy Sealer as a comparable replacement." Thanks

[clausont]

Originally Posted by bailsout

I sometimes find it better to drill holes all the way through thus allowing better drying and easier filling, taping off the holes to later contain the injections.

I can see possible benefits and drawbacks of both ways. Thanks

[clausont]

Originally Posted by Apollo19.5

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.

Most of the interior hull of this Wylie 38 was left clear with exposed epoxy/wood grain visible. Some of it was painted white. If I have the ambition, I may remove the white interior paint and leave it all wood grain (epoxy sealed of course).

[clausont]

Originally Posted by 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!

PM'd you! Looking forward to conversation on this. Thanks

[clausont]

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?

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

Jim

Yes Jim. My terminology may be wrong. Your description is what the builder described to me and what I observe in the hull. The main strip planking is 3/4 x 3/4 vertical grain Doug fir. From the visible grain that I see, he chose his materials very carefully. One exterior layer is 1/4" Cedar veneer and one more veneer layer which I now forget what material it was. He said the main hull thickness is 1 1/4" whereas the design spec was total of 7/8" thick. He left me the original photo album of the construction. I'll try to scan and post a few of the construction photos.

[tomtriad]

From your recent desciption, it appears you have a combination strip planked (dimensional 3/4 x 3/4 )and cold molded (veneers) hull, built with epoxy. I think you may have your materials reversed - it's more typical to use cedar for strip planking and fir or mahagany veneers for cold molding. This would be good for you as cedar is rot resistant and could still be sound even after years of water intrusion. on WEST construction, saturation is a misnomer - only the mating surfaces of the wood get coated with epoxy - the 'pox will soak up into the end grain to some degree, but only where the end grain is exposed. Your photo distinctly shows 'glass roving under the paint on the planking nearest the shear clamp. The deck overhead is also showing signs of water migration - you should sound and check that carefully.

I have a 40 year old 42' cold molded (veneers) trimaran, and I have successfully relaminated veneers on the rare occasion where water has migrated in - notably on the deck edges which are unfiberglassed plywood; the entire exterior apart from the deck edge is glassed. To treat these, I wedge the plys apart (if they are not rotted), inject acetone (acetone combines with water to make acetal alcohol which evaporates at 98 degrees F), dry it with a hair dryer, inject epoxy, and clamp it down with sheet rock screws through fender washers. If the plywood is punky, not just wet, I remove it and glue in new - as you will have to do if your strip planking has rotted (fir does not resist rot the way cedar does).

I also repaired a 2' long x 3" wide crack in the hull using this technique following a dismasting.

My daggerboard core is built of dimensional redwood (similar to your cedar strip), covered with layers of glass - it had soaked up water after a grounding. I drilled 1/4" holes every 2-3 inches, saturated it with acetone, and placed it over heaters for several days until it dried sufficiently, then taped over one side and filled the holes with thickend 'pox. This is what I would do with your problem area on the hull. Since I suspect you have veneers diagonally glued over the strip, you may get lucky and have the water intrusion in the strip planked cedar only. In this case, stripping off the glass from the inside (yes you have glass) and paint, then carefully drilling small 3/4" deep holes, saturating with acetone and putting fans/heaters (careful you don't the house down) to dry it, then inject it with epoxy. You might wish to examine the veneers by routing out a section of the interior strip planking to examine them to see if they have water intrusion too. You can easily refill a removed section with wood or epoxy thickened with balloons and silica (peanut butter consistancy).


I did one repair on a void between layers of the veneers on the underside of one of my wingdeck beams, by drilling 1/8" holes every 2 or 3 inches, and injecting epoxy slightly thickened with microballoons; the void was dry as it was always above water, end no leaking from the deck overhead). I clamped it down with sticks forced between the top veneer layer and the overhead deck.

You must carefully examine the damage and assess it accurately to do the right repair. I suspect from the check/seam patterns that your deck may be plywood - if this is the case, and you see checkerboard like lines under the paint, it will be saturated with water as well.

I hope this helps.

[ausnp84]

Thanks guys. Our recently-purchased cold moulded tri also has some moisture issues, so this is really helpful!

N

[Catalacmarc]

A historical note, the Fairey company in England produced a line of hot molded twin drop keel boats up to 30 ft. using the same technology as built the famous Mosquito bomber/fighter of WW2. The Atalantas being the most well known. They have much the same problem with rot and are often restored in the UK as well as issues with the adhesive over time. The restorers might be another source of information on fixes. As I understand it, they are based on the airborne lifeboat design by Uffa Fox.

[Capn Rick]

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[BBill]

Epoxy saturation on wood is 99% a myth. Take the most punky wood you can find, drill 1/4" holes in it as directed and use the slowest cure and thinnest brand resin you can find. Come back in a week or whatever and start cutting to see how far it penetrates...which you will find is so little it shouldn't be considered as structural penetration. It should be called epoxy coating. The scientist here should be able to describe exactly why resin molecules are too large to penetrate deeply. That's the root of the problem in which vendor pics showing deep penetration are 99% bogus.

I know this goes against the grain of those here but do yourself a favor and test the resin you think will restore rotted wood by drilling holes to penetrate the surrounding area. You can start by just pouring the resin into a coffee filter, which is like punky wood at best.

[clausont]

Originally Posted by BBill

Epoxy saturation on wood is 99% a myth. Take the most punky wood you can find, drill 1/4" holes in it as directed and use the slowest cure and thinnest brand resin you can find. Come back in a week or whatever and start cutting to see how far it penetrates...which you will find is so little it shouldn't be considered as structural penetration. It should be called epoxy coating. The scientist here should be able to describe exactly why resin molecules are too large to penetrate deeply. That's the root of the problem in which vendor pics showing deep penetration are 99% bogus.

I know this goes against the grain of those here but do yourself a favor and test the resin you think will restore rotted wood by drilling holes to penetrate the surrounding area. You can start by just pouring the resin into a coffee filter, which is like punky wood at best.

Hi Bill, Actually, I don't have to do the test on epoxy penetration - you are absolutely correct. I firmly believe in replacing rotten wood if at all possibly. I don't like just putting a bandaid on things. I was looking at a test that West system did on Epoxy penetration and even they show that penetration is pretty much surface only with slightly more end grain penetration depending on the wood density. Thanks

[clausont]

Originally Posted by tomtriad

From your recent desciption, it appears you have a combination strip planked (dimensional 3/4 x 3/4 )and cold molded (veneers) hull, built with epoxy. I think you may have your materials reversed - it's more typical to use cedar for strip planking and fir or mahagany veneers for cold molding. This would be good for you as cedar is rot resistant and could still be sound even after years of water intrusion. on WEST construction, saturation is a misnomer - only the mating surfaces of the wood get coated with epoxy - the 'pox will soak up into the end grain to some degree, but only where the end grain is exposed. Your photo distinctly shows 'glass roving under the paint on the planking nearest the shear clamp. The deck overhead is also showing signs of water migration - you should sound and check that carefully.

I will know for sure on the glass roving pretty soon as we are getting started stripping the rotten sheer strake out. The lower skin of the deck in the photo definitely has rot issues as well. We will find out the extent of it when we open it up. Prior to buying the boat, we spent 2 days sounding the entire boat carefully and are pretty confident in the extent of the rot. There are a couple small spots we missed even at that.

Originally Posted by tomtriad

I have a 40 year old 42' cold molded (veneers) trimaran, and I have successfully relaminated veneers on the rare occasion where water has migrated in - notably on the deck edges which are unfiberglassed plywood; the entire exterior apart from the deck edge is glassed. To treat these, I wedge the plys apart (if they are not rotted), inject acetone (acetone combines with water to make acetal alcohol which evaporates at 98 degrees F), dry it with a hair dryer, inject epoxy, and clamp it down with sheet rock screws through fender washers. If the plywood is punky, not just wet, I remove it and glue in new - as you will have to do if your strip planking has rotted (fir does not resist rot the way cedar does).

I also repaired a 2' long x 3" wide crack in the hull using this technique following a dismasting.

Thanks! That's good to know about the acetone. I will definitely keep this method in mind when I get started.

Originally Posted by tomtriad

My daggerboard core is built of dimensional redwood (similar to your cedar strip), covered with layers of glass - it had soaked up water after a grounding. I drilled 1/4" holes every 2-3 inches, saturated it with acetone, and placed it over heaters for several days until it dried sufficiently, then taped over one side and filled the holes with thickend 'pox. This is what I would do with your problem area on the hull. Since I suspect you have veneers diagonally glued over the strip, you may get lucky and have the water intrusion in the strip planked cedar only. In this case, stripping off the glass from the inside (yes you have glass) and paint, then carefully drilling small 3/4" deep holes, saturating with acetone and putting fans/heaters (careful you don't the house down) to dry it, then inject it with epoxy. You might wish to examine the veneers by routing out a section of the interior strip planking to examine them to see if they have water intrusion too. You can easily refill a removed section with wood or epoxy thickened with balloons and silica (peanut butter consistancy).


I did one repair on a void between layers of the veneers on the underside of one of my wingdeck beams, by drilling 1/8" holes every 2 or 3 inches, and injecting epoxy slightly thickened with microballoons; the void was dry as it was always above water, end no leaking from the deck overhead). I clamped it down with sticks forced between the top veneer layer and the overhead deck.

You must carefully examine the damage and assess it accurately to do the right repair. I suspect from the check/seam patterns that your deck may be plywood - if this is the case, and you see checkerboard like lines under the paint, it will be saturated with water as well.

I hope this helps.

This does help a lot. I really appreciate the time everyone has taken here to help guide me on the way. I will continue to update this post as I make the repairs. Thanks!

[clausont]

And the verdict is in: There is no fiberglass, cloth, mat, roving or anything else like that on the inside of the hull. What you see in the picture is simply the wood grain showing through the paint and epoxy inside. The inside of the hull is coated in epoxy, but no glass.