Soft Deck Repair

[davidpm]

I have looked a many, many plastic classics the last few months. Many of them have soft decks. This seems to be the death knell for a boat that has max value of maybe 15 to 20 thousand. Wouldn’t it be lovely (queue “Sound of Music” soundtrack) to come up with an efficient way to fix a deck to save these boats. I know the right way to do it. I’ve seen the pictures
http://www.triton381.com/projects/re...on/recore.html.
http://www.westsystem.com/ewmag/19/Replacing_Core.html
Maybe there is a quicker way that for some boats would be good enough. Better than the alternative, the chainsaw.
The following methods will probably not work; I have never seen them in print before. The intent is to provoke discussion, possibly learn a technique you have used successfully but never discussed in public. Maybe one of my wacky ideas could be mutated by wiser people into something workable.

Bad Idea #1:
1. Remove the cabin port lights and hatches, deck hardware, rub rail etc. I know, I know there are a ton of things to take off and reattach.
2. Build a cradle just like a hull cradle but with many more contact points for the deck to support the deck shape.
3. Use a metal saw to cut the hull deck bolts.
4. Invert the whole deck. Now you know why you need the deck cradle. How much can a deck weigh anyway?
5. So far I have not seen much softness in the cabin but always on side deck. Cut large portions of inside deck liner off. Fix core and reattach deck liner. Patch joints with accent trim.
6. Flip deck over and reattach.

Bad Idea #2
1. Create a Sistine Chapel type of scaffolding inside the boat so you can lie down and work on the underside of the deck in comfort.
2. Using a plumber’s saw cut out 4” to 6” holes in the inside skin in a honey comb pattern.
3. Replace core material and glue back circles.
4. Add a layer or two of fiberglass cloth for strength.
5. Finish with wood strips, soft headliner etc.

Of course it is unlikely to expect that any deck job is going to be easy. The problem with the Triton381 restore method is that re-faring and refinishing the deck takes a very high level of skill if it is to look good. I’m hoping that working from the inside where mistakes can be hidden easier may be faster.

What do you all think?

[sailingdog]

Umm... the first method is a really bad idea. The deck provides much of the strength of a boat, in terms of rigidity, and I seriously doubt that you could reattach the severed deck to the rest of the boat well enough to take the loads that a sailboat tends to exert on the deck. The chances of the deck leaking at the points it is re-attached is exceptionally high as well...

As for bad idea #2. same problem... you're effectively gutting most of the strength of the deck and then trying to put it back in patchwork pieces. When you're re-coring a soft deck, you really want the core material to be a large single piece rather than little pieces. The gaps between the pieces of new core can introduce "hard" spots which can cause the laminate to hinge at that point. If the laminate starts to flex at those hard spots, it will fail. You can't just stuff core material in through the little holes you cut, since it will be hard to guarantee that it will bond properly to the remaining honeycomb structure—leading to early delamination and voids.

The advantage of working from the outside, as in the Triton381 project, is that gravity is on your side...rather than working against you. It is also easier to work on larger areas, since you aren't confined by the cabin and the interior furniture.

If you're applying a non-skid treatment to the deck, the refinishing process doesn't have to be all that perfect. Of course, if the existing deck exterior is in good shape, you could always make a mold of it, and then after finishing the core repair, use the mold to help re-finish the deck. But making such a mold would be a fairly labor intensive job, and might not result in an acceptable finish.

[Maine Sail]

Originally Posted by davidpm

I have looked a many, many plastic classics the last few months. Many of them have soft decks. This seems to be the death knell for a boat that has max value of maybe 15 to 20 thousand. Wouldn’t it be lovely (queue “Sound of Music” soundtrack) to come up with an efficient way to fix a deck to save these boats. I know the right way to do it. I’ve seen the pictures
http://www.triton381.com/projects/re...on/recore.html.
http://www.westsystem.com/ewmag/19/Replacing_Core.html
Maybe there is a quicker way that for some boats would be good enough. Better than the alternative, the chainsaw.
The following methods will probably not work; I have never seen them in print before. The intent is to provoke discussion, possibly learn a technique you have used successfully but never discussed in public. Maybe one of my wacky ideas could be mutated by wiser people into something workable.

Bad Idea #1:
1. Remove the cabin port lights and hatches, deck hardware, rub rail etc. I know, I know there are a ton of things to take off and reattach.
2. Build a cradle just like a hull cradle but with many more contact points for the deck to support the deck shape.
3. Use a metal saw to cut the hull deck bolts.
4. Invert the whole deck. Now you know why you need the deck cradle. How much can a deck weigh anyway?
5. So far I have not seen much softness in the cabin but always on side deck. Cut large portions of inside deck liner off. Fix core and reattach deck liner. Patch joints with accent trim.
6. Flip deck over and reattach.

Bad Idea #2
1. Create a Sistine Chapel type of scaffolding inside the boat so you can lie down and work on the underside of the deck in comfort.
2. Using a plumber’s saw cut out 4” to 6” holes in the inside skin in a honey comb pattern.
3. Replace core material and glue back circles.
4. Add a layer or two of fiberglass cloth for strength.
5. Finish with wood strips, soft headliner etc.

Of course it is unlikely to expect that any deck job is going to be easy. The problem with the Triton381 restore method is that re-faring and refinishing the deck takes a very high level of skill if it is to look good. I’m hoping that working from the inside where mistakes can be hidden easier may be faster.

What do you all think?

Both of the methods you mention will require a far deeper level of skill, time and money than what is required by doing it the right way or the Tim Lackey way. How much can a deck weigh? LOTS especially wet!! Not to mention that the hull and deck won't want to go back together or come apart for that matter and you'll need as ceiling crane/hoist..

Filling, fairing and re-doing the non skid is actually a very low tech job and does not entail or require a lot of skill just patience, a good eye and a good sander... Oh and reading some books or web sites like Tim's...

[davidpm]

What is a good non-skid surface?

[zz4gta]

Making a mold would be pretty labor intensive. A template in crucial areas might work a little better, and you can make those out of heavy cardboard or plastic sheets, etc. Make a couple for cross sections and one that goes lengthwise of the deck. Should get you close with just the cost of time and cardboard. A contour gauge would also help.

[sailingdog]

It depends. You can mold in a non-skid texture into the epoxy fairing or gelcoat. You can paint on a non-skid surface, like DuraBak or with a traditional non-skid deckpaint. Or you can apply a non-skid surface treatment like Tredmaster.

Originally Posted by davidpm

What is a good non-skid surface?

[Rockter]

The problem will be that once the deck is taken off like that, the hull will move... perhaps not much, but it will move. Getting the deck back on there again may not be so easy.

It is such a stupid material to use for deck core. It rots. Of all the modern material choices, do we really have to use balsa? What's wrong with honeycomb? Does that rot?

[sailingdog]

Rockter-

End-grain balsa does have some benefits over some of the other materials.

First, it tends to not let water migrate over long distances, keeping the damage relatively localized, compared to a foam core material.

Second, it tends to be much more stable in high heat, so a dark colored deck, might deform if cored with foam, would not if cored with balsa.

Third, balsa has much greater shear and compressive strength compared to the foams generally used in boat laminates.

Fourth, end-grain balsa tends to bond to the laminate skins far better than do the foams, due to the capillary action of the balsa helping the resin stick to it. Most of the foams have to be coated with some sort of material to make the resin stick to it properly, and that is more likely to leave voids in the laminate.

Yes, balsa will rot... but only if it is exposed to water and air... if the balsa is properly sealed and potted where there are penetrations through the cored laminate, it is a very good material, and likely to last a very long time.

[deniseO30]

let me take a stab at this one. ( I think allot) Layout a grid pattern.. drill holes in the deck, but not through the underside. The holes need to be big enough to let you push a flexible rod that will make channels interconnecting to each hole from at least 4 directions. Once the channels are clear to each hole, use a pump of some sort that will force epoxy, (low visc) through the channels, allowing the core to be saturated. Now after it's all been pumped and the core is saturated.. drill though, and with bolts and large washers draw the deck down to the ceiling to insure the core is compressed enough for the epoxy to lock it all together. After all the curing is done the holes can be filled with epoxy putty. This would not deal with refinishing the non skid. (sand it off and make it a new top coat of glass? or new non skid paint? This is a variation of how they reattach plaster to old wood lath in old building walls.

I know! I think too much!

[sailingdog]

The problem is that the channels will be voids or filled with relatively brittle solid epoxy. Solid epoxy is relatively brittle, which is why they generally thicken it.