And so it Begins: The Teak Deck Removal Project

[minaret]

That's a big deck, you'd save a ton of money if you went with poly for your layup instead. Don't go with anything heavier than a 1708. I'd do one 1708 and two 1.5 oz matt in poly with peel ply followed by fairing in poly, which will save you another ton of money. Then I'd finish in gel, for another fat savings, and a better finish. Result would be savings=metric ****ton. Plus a better, faster job. Also, I'd do a great deal more vessel protect-right now. One false move with the grinder and...


Sometimes I'm envious of you amateurs on that front. No way would I step into this job without days of vessel protect first. You guys can just dive in, and damn the consequences! Keep at it.

[SV THIRD DAY]

Originally Posted by minaret

Sometimes I'm envious of you amateurs on that front. No way would I step into this job without days of vessel protect first. You guys can just dive in, and damn the consequences! Keep at it.

Stupidity is often mistaken for boldness...the less I know about what can go wrong and what I can screw up, the better I sleep at night...ha ha ha

[UNCIVILIZED]

Minaret, do you have your computer setup so that if someone mentions your name, an alarm sounds? You certainly got here quickly after my post

Anyway, I'm curious to hear of what tricks you'd use to get poly to adhere well to things. If you'd be so kind. As I'd have used epoxy for the job, giving zero thought to poly for the job.

[minaret]

Originally Posted by SV THIRD DAY

Stupidity is often mistaken for boldness...the less I know about what can go wrong and what I can screw up, the better I sleep at night...ha ha ha

Please do mask much more at the laminating stage though please. Always plan ahead for a spilled pot of resin. JMHA.

[minaret]

Originally Posted by UNCIVILIZED

Minaret, do you have your computer setup so that if someone mentions your name, an alarm sounds? You certainly got here quickly after my post

Anyway, I'm curious to hear of what tricks you'd use to get poly to adhere well to things. If you'd be so kind. As I'd have used epoxy for the job, giving zero thought to poly for the job.

16-24 grit grinder profile on bare glass only, super thorough very wet multiple acetone washes, and a good quality poly isotropic resin (not orthotropic resin) is all. Nothing special. All the pro yards don't do jobs like this this way to save money as is often said online; au contraire, the more expensive the materials they sell to the customer the more they make on markup.


You'd be surprised; just happened to be browsing while on the hook in the islands. Haven't been around much lately; gone sailing!

[Exile]

Originally Posted by minaret

16-24 grit grinder profile on bare glass only, super thorough very wet multiple acetone washes, and a good quality poly isotropic resin (not orthotropic resin) is all. Nothing special. All the pro yards don't do jobs like this this way to save money as is often said online; au contraire, the more expensive the materials they sell to the customer the more they make on markup.


You'd be surprised; just happened to be browsing while on the hook in the islands. Haven't been around much lately; gone sailing!

Good to hear you're out sailing Min! Thanks for checking in and helping out while away from the shop. These threads are always valuable, and with Rich as master of ceremonies this one is bound to be quite entertaining too.

[exMaggieDrum]

After reviewing the thread once more (a good thread) and seeing the questions on what kind of deck coring to use, I spent a couple of hours of intense research online looking at different alternatives. As usual, you get many different opinions on the alternatives.

Some people have used, and some recommend, Coosa board. It is advertised (primarily) by the manufacturer as use for structural applications. They do not go out of their way to specify it as the "go to" deck coring material. I found many references from owners who used it but not as many as for the foam type coring. It is far heavier and much less flexible. And pretty expensive too. I like the idea of the structural rigidity but that comes with the price of installing it on anything with a camber as it does not bend. Often used for transoms, which are usually flat.

The foam cores, divinyl, corecell and others, look good. Much more flexible and much lighter. But I found a few stories about how the foams can self-destruct with heat - as can be found on a deck in tropical areas. And they can crumble over time. Basically they are not as long-lasting. I tried to find out some specific pros and cons on this specific issue and didn't have much success.

They seem widely used though. There also were some stories about how hard they are to get proper and consistent bonds with the fiberglass resins (epoxy or other). They seem to provide a very strong core but not a good media to hold screws for deck fittings. And I saw one reference to the potential for some water absorption in the cells themselves. Inconsistent bonding to the top laminate can lead to pooling of water that never goes away.

On top of it all, I found many favorable recommendations for balsa coring. With notes that you have to be very careful for any penetrations by coring a hole oversize and filling with resin and then drilling for the screw or bolts. But, some say that with all the vibration and pounding a boat takes that regardless of how careful you are there will be cracks that develop which let in water leading to wet core and rot. It is very light of course and the least expensive.

So - is there any place to get better info on the pros and cons of the different materials that can be used for deck coring? Something that is not just hype from manufacturers and biased distributors. Having said that some distributors are more forthcoming than others but it's hard to tell sometimes. (understatement).

My hat is off to Rich for tackling his deck, and for sharing the saga. I have it to look forward to taking off the teak deck on my boat too. I won't have near the area that he does but enough. I also don't know yet how much damage I will find but I expect to find some. So I will need coring for some if not all of the deck replacement.

[mike66]

Some of the options mentioned for cores seem to be a cost/benifit question. Example: my 1986 Albin has a couple of soft spots. I am 65 yrs old. Resale of my boat ? $50,000 if lucky. (I never am.) Ignore? Fix the correct way? Penerating epoxy and live with it? Sort of like a prostate cancer diagnosis in a 75 year old.

Sent from my SAMSUNG-SGH-I337 using Cruisers Sailing Forum mobile app

[minaret]

Originally Posted by exMaggieDrum

After reviewing the thread once more (a good thread) and seeing the questions on what kind of deck coring to use, I spent a couple of hours of intense research online looking at different alternatives. As usual, you get many different opinions on the alternatives.

Some people have used, and some recommend, Coosa board. It is advertised (primarily) by the manufacturer as use for structural applications. They do not go out of their way to specify it as the "go to" deck coring material. I found many references from owners who used it but not as many as for the foam type coring. It is far heavier and much less flexible. And pretty expensive too. I like the idea of the structural rigidity but that comes with the price of installing it on anything with a camber as it does not bend. Often used for transoms, which are usually flat.

The foam cores, divinyl, corecell and others, look good. Much more flexible and much lighter. But I found a few stories about how the foams can self-destruct with heat - as can be found on a deck in tropical areas. And they can crumble over time. Basically they are not as long-lasting. I tried to find out some specific pros and cons on this specific issue and didn't have much success.

They seem widely used though. There also were some stories about how hard they are to get proper and consistent bonds with the fiberglass resins (epoxy or other). They seem to provide a very strong core but not a good media to hold screws for deck fittings. And I saw one reference to the potential for some water absorption in the cells themselves. Inconsistent bonding to the top laminate can lead to pooling of water that never goes away.

On top of it all, I found many favorable recommendations for balsa coring. With notes that you have to be very careful for any penetrations by coring a hole oversize and filling with resin and then drilling for the screw or bolts. But, some say that with all the vibration and pounding a boat takes that regardless of how careful you are there will be cracks that develop which let in water leading to wet core and rot. It is very light of course and the least expensive.

So - is there any place to get better info on the pros and cons of the different materials that can be used for deck coring? Something that is not just hype from manufacturers and biased distributors. Having said that some distributors are more forthcoming than others but it's hard to tell sometimes. (understatement).

My hat is off to Rich for tackling his deck, and for sharing the saga. I have it to look forward to taking off the teak deck on my boat too. I won't have near the area that he does but enough. I also don't know yet how much damage I will find but I expect to find some. So I will need coring for some if not all of the deck replacement.

You should seriously consider getting some pro help. I'm doing a Maple Leaf 54 this winter and will do a thread on its deck replacement. Not as complex as mine, but still ought to be a good one. Use Coosa as a replacement for ply core, where the added strength was likely designed in. Use foam as a replacement for balsa. Coosa can be bent just like any other stiff material; either kerf the back side on a table saw, or use multiple layers of thinner material vacuum bagged in place. 3 layers of 1/4" Coosa bends easily for even the most extreme deck camber and replaces 3/4" core. Just be sure to bore hydraulic lock relief holes in your core.

[exMaggieDrum]

Originally Posted by minaret

You should seriously consider getting some pro help. I'm doing a Maple Leaf 54 this winter and will do a thread on its deck replacement. Not as complex as mine, but still ought to be a good one. Use Coosa as a replacement for ply core, where the added strength was likely designed in. Use foam as a replacement for balsa. Coosa can be bent just like any other stiff material; either kerf the back side on a table saw, or use multiple layers of thinner material vacuum bagged in place. 3 layers of 1/4" Coosa bends easily for even the most extreme deck camber and replaces 3/4" core. Just be sure to bore hydraulic lock relief holes in your core.

Great answer Minaret. Right now I don't have any reason to believe I have any core problems but the boat is 30+ years old and the teak deck is well worn and even buckles slightly when walked on. It does not feel like the deck is moving under it but I expect to find some problem areas.

I try not to overestimate my skills on some critical areas. I appreciate your recommendation for pro help. At a minimum I will get advice locally. I worked at a largish full service boat yard for several years and the owner owes me a few favors. But I'll pay for good advice too.

Can you elaborate on the hydraulic relief holes? Is that to allow some expansion as the epoxy cures or something else?

[SV THIRD DAY]

As an update, 90% of the balsa core on this 1977 boat is prefect. Dry...intact...and it's impressive to see how well it looks when we have cut into dry areas or in the act of removing the wet areas and continuing a bit into the dry core. I think a big factor in why so much of my balsa core is in great shape is because in 1984 a previous owner put down fiberglass, paint and non-skid right over the original teak decks. This gave an extra layer of water penetration protection, especially on the bow and forward parts of the deck that had a good slope to them. The wet core areas were where the slops flattened out particularly right in front of the pilot house structure.

This is a close up I just snapped (yes I will do anything for a distraction) of the layers of the Deck. You can see the top fiberglass layer, followed by two balsa core layers with a thin glass layer in between. The very bottom layer is fiberglass with some wood grain still on it and not cleaned up well yet.


So from where I am today with the project.
All of the wet or suspect core is cut out and gone.
All of the fiberglass deck is sanded and cleaned.

So today I'm going to start filling in the screw holes on the deck that will remain and heading over to a local fiberglass shop just on a look see mission. I still have not decided on what new "core" material to use. Cost isn't a factor to me since the actual area is not that large, but ease of install and dealing with is. I need to build back up about 3/4 so I'm thinking 3 layers of 1/4 Corcel or marine ply...I honestly haven't decided and ordered that yet.

Once the core is replaced and made to be even with the existing deck (I'm sure that will be a lot of work) I will then take Minaret's advice and go with a 1708 glass mat over the entire deck for starters followed by 2-layers of 2-4Oz mat.

So far I'm feeling pretty good about the progress and project, but remember ignorance is bliss.

The last time I was told I should get some professional help, it resulted in a $250/hr counseling session where I was asked about my childhood and if I remembered the first time I sent to the bathroom by myself. (??#!$)

[minaret]

Originally Posted by SV THIRD DAY

As an update, 90% of the balsa core on this 1977 boat is prefect. Dry...intact...and it's impressive to see how well it looks when we have cut into dry areas or in the act of removing the wet areas and continuing a bit into the dry core. I think a big factor in why so much of my balsa core is in great shape is because in 1984 a previous owner put down fiberglass, paint and non-skid right over the original teak decks. This gave an extra layer of water penetration protection, especially on the bow and forward parts of the deck that had a good slope to them. The wet core areas were where the slops flattened out particularly right in front of the pilot house structure.

This is a close up I just snapped (yes I will do anything for a distraction) of the layers of the Deck. You can see the top fiberglass layer, followed by two balsa core layers with a thin glass layer in between. The very bottom layer is fiberglass with some wood grain still on it and not cleaned up well yet.


So from where I am today with the project.
All of the wet or suspect core is cut out and gone.
All of the fiberglass deck is sanded and cleaned.

So today I'm going to start filling in the screw holes on the deck that will remain and heading over to a local fiberglass shop just on a look see mission. I still have not decided on what new "core" material to use. Cost isn't a factor to me since the actual area is not that large, but ease of install and dealing with is. I need to build back up about 3/4 so I'm thinking 3 layers of 1/4 Corcel or marine ply...I honestly haven't decided and ordered that yet.

Once the core is replaced and made to be even with the existing deck (I'm sure that will be a lot of work) I will then take Minaret's advice and go with a 1708 glass mat over the entire deck for starters followed by 2-layers of 2-4Oz mat.

So far I'm feeling pretty good about the progress and project, but remember ignorance is bliss.

The last time I was told I should get some professional help, it resulted in a $250/hr counseling session where I was asked about my childhood and if I remembered the first time I sent to the bathroom by myself. (??#!$)

Er, that's not balsa core. That's the old Taiwan "shingle method". No balsa there.


Hate to say it, but that is the worst coring method out there. Have redone many of these. You are very lucky if it's all dry and solid. Have you put a moisture meter on it? I'd try very hard to keep it dry, from your close up it looks like it's delaminated both between core and bottom skin and between core and center skin. How far can you insert a very thin putty knife in these areas? I'd consider it the rare candidate for massive epoxy injection into the core if it really is dry and solid but delaminated.

[SV THIRD DAY]

Originally Posted by minaret

Er, that's not balsa core. That's the old Taiwan "shingle method". No balsa there.

I thought shingles was like chicken pox...but it's in great shape whatever it is...ha ha

[minaret]

Originally Posted by SV THIRD DAY

Well the project is coming along nicely.
The teak is gone and we have also wire brushed with the grinder all of the black adhesive off the deck to expose the fiberglass deck. The wet areas are cut out (a very small area of the overall deck) and now we are getting close to the fun of Epoxy and Fiberglass.

I do have a technical question that I am researching that I will throw out to the experts. I need to put a few 2-3 layers of fiberglass down on the deck to give back some rigidity that removing the teak took away. What I'm questioning is what weight of cloth to use. This is a flat big surface. I've had recommendations of 28oz (which seems a bit heavy to me) followed by a 10oz or 12oz.

Any recommendations from the group?


This photos shows the grinder with the wire brush attachment that we found to be the best way to both remove the black adhesive and etch away just enough fiberglass to give a nice clean surface ready to lay new epoxy and glass down on.


I'll tell you right now, without my 17yr old son busting his rear end, this job would be a LOT harder. Here he is prying up the top fiberglass layer over a wet core area so we can dig out the potting soil. You can see some core test holes drilled in the deck with a 1" holesaw to find where the wet ends and dry core begins. Oh and yes, those are safety Crocs he is wearing.



Ah...the famous wet core shot. Out it comes. In the background you can see where we removed the wet core around the heater stack and that area is ready for the Corecell to be epoxied in place.

It was clear it's the shingle method from this pic early on. Close up makes it triple clear. This method involved bonding squares of cheap ply to the deck. If you look at it edge on you can see the ply lams with big center cores. No end grain, they rely on the filler between squares to isolate any water intrusion. This rarely works. I'd be sure to moisture meter and carefully hammer sound everything before assuming core is good. Thorough core sampling is good too. Be sure to core sample through both layers-I've seen cases where the bottom layer is rotten but the top is not, due to separation by the center skin.

[SV THIRD DAY]

Originally Posted by minaret

It was clear it's the shingle method from this pic early on. Close up makes it triple clear. This method involved bonding squares of cheap ply to the deck. If you look at it edge on you can see the ply lams with big center cores. No end grain, they rely on the filler between squares to isolate any water intrusion. This rarely works. I'd be sure to moisture meter and carefully hammer sound everything before assuming core is good. Thorough core sampling is good too.

I used the 1/2" hole saw method...drilled holes all around the deck and it all came up bone dry except for the section right in front of the pilot house.