Boat floor replacement... where to begin?

MrCableTek

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boat1.JPG I have procured the boat I wish to rebuild at this point and have discovered that the floor has some squishy spots. I know it could be bad and I need to assess the damage but where do I begin cutting? The back of the boat (transom and rear portion of the stringers) seems to be quite solid. No squish, solid "thud" with a rubber mallet, and no apparent delamination. The problem (as others have mentioned is common with a vessel from Dixie Boat Works) is around the bases of the seats. So, where and how do I cut so that it can be put back together without looking like crap? The deck is one solid piece but for the hatches from what I can tell. I really don't want to ruin this thing from jump here. Suggestions? I will attempt to upload photos.
 
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jigngrub

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Appearing to be solid and what you actually have will probably be 2 different things. Even if your wood is solid but wet it'll still need to be replaced. Rot doesn't usually localize below deck on a fiberglass boat and if there are soft spots in the deck the below deck area will be widespread with undesirable material.
 

MrCableTek

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I'm going to do some more investigation tomorrow but there seems to be a gap between the soft portion of the floor and the stringer. I think the floor is bad from where the screws went through the seats. The screws don't go all the way through to the stringers either so they may still be okay. I still have the problem of knowing how to check everything without cutting the whole top off of the boat.
 

jigngrub

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Remove the seats and whatever else in the way of accessing the soft spots, cut out the soft spot area. You'll want to remove the carpet before doing any cutting. Examine the below deck status of the stringers if you expose one and the foam. If the foam is wet cut a larger area, if still wet in the larger area keep cutting until you reach dry material... you'll probably end up removing all of the decking anyway.

It's difficult to cut out and patch back an area on a fiberglass boat, and is usually not the way thing go anyway... but start at the soft spots, think of it as exploratory surgery for cancer (boat cancer).

Keep trying to post pics, pics will help us help you better. If you can't get a forum upload get a Photobucket account and post them through there, it's actually the best way to post pics here right now.
 

MrCableTek

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Sorry if I'm being dense but this is a fiberglass boat. How and where should I cut the floor if the soft spot is around the seats? Should I go to a joint or out to the gunwale? How do I go about cutting in a manner that will allow me to put it back together and not look like crap? I did get the pictures to post. Can you see them or did I do it wrong?
 

pckeen

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Hi,

The advice above is good, but something caught my eye. If you are saying that the floor has separated from the stringers, the likely result is rot. However, it is possible that the deck has bowed upwards, but is still solid - this could account for the springiness. Don't want to give you unrealistic cause for hope - the far more likely result is that this is rot.

Before you start cutting into all this, you can work out how extensive the damage is by working out where the stringers are. Drill into the stringers and transom. If the wood chips come out golden - you wood in that case is good. If black, then the wood is rotten, and needs replacement.

The problem that the other users are referring to is that boats rot from the inside out - by the time sponginess shows up on the floor of the boat, the stringers are usually long gone - replacing a single section of deck is like repainting a house that is on a rotten foundation. Usually when the stringers are gone, the transom is too.

Before you start cutting into this, take a look at some of the restoration threads on here - that will give you a better idea of what you are actually looking at for a proper repair (it isn't a case of replacing part of the deck). If you read through a couple of resto. threads, that will answer many of your questions.
 

pckeen

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Couldn't see the photos - your best bet is to open a photobucket account, upload web-sized images, then click on the box to the right of IMG on the image you want, and paste it into your iboats posting.
 

Woodonglass

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Welcome to iBoats!
It''s hard to tell from the one pic you've posted but does your deck have a texture or not? If not you should be able to cut a section and patch it with little problem. If it has a texture, matching the texture will be the hardest part once you try to patch back in the hole IF it comes to that. The hatch shown in the picture, should give you an idea as to the thickness of the deck. As to where to cut...If the soft spot is around the base of the seat, then remove the seat and then Set a circular saw to the exact thickness of the deck material and cut out a section of the deck approximately 2' square. When it's time to put it back you'll put cleats in to support the cut out section and then fill the seam with thickened resin and then use Glass mat to bridge the seam and fairing material to blend it . You'll be able to make it "Disappear". You should Hope for the Best but Plan for the worst. Boats typically Rot from the bottom Up so if the deck is soft there's a High likelihood that the substructure (Stringers, Bulkheads and Transom) have all been compromised as well. A rubber mallet is not a good method for determining the structural integrity of these components. You'll need to drill core samples to make certain they are in good condition. You can only do that once the deck has been removed and you have gained access to them. Post up some more pics of the over all boat and give us more details. This will allow us to give you the best advice on how you should proceed.
 
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MrCableTek

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I'm going out tomorrow to clean her up real good and do some more investigation. I can feel the wood under the fiberglass floor on the right side through the hatch when it's open. The wood underneath is nasty and falling apart and the fiberglass encasing it is beginning to come apart. Anyway, tomorrow I'm going to take a bunch of pics and hopefully figure out what I need to do to get her seaworthy again.
 

jigngrub

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Ok, your pics posted now.

If the bottom of the decking is falling apart, you need to prepare yourself for the worst and you will more than likely end up removing all of the decking and replacing your stringers and probably your transom too. In other words your boat will probably be a full restoration project and not a patch job so it doesn't matter how you start cutting your decking.

Your best bet will be to use a Skill saw with the blade set at about 5/8" deep. Cut around the entire perimeter or your deck at the side walls and transom and lift all of your decking out. I know this probably sounds extreme to you and much more than you thought it was going to take, but you'll see what we're talking about after you get started.
 

MrCableTek

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walkaroundcut_zpsdc107f4e.jpg Okay, I found a picture after much searching that I think answers my question. Is this how I am supposed to cut it out?
 

jigngrub

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Yup, pretty much.

... and you'll come back later and remove the little stuff left as needed. But that pic will give you a good idea of what needs to happen and what everything will look like below deck, maybe not exact... but very similar.
 

MrCableTek

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20140906_125842_zpsilt2qcv3.jpg 20140906_125739_zpsg6iyo0tu.jpg
20140906_125854_zpskm4lcspg.jpg Here are some more pictures of the boat. I have removed the seats and hatch covers from the deck. We're tearing in to her tomorrow. I have a circular saw with a fine tooth blade and one of those cool vibrating saws. If anyone else has any advice on how or where to cut, this would be the time.
 

jigngrub

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Like I said last night, set the blade depth on that circular saw for 5/8" deep. You don't want to cut too deep and go through the hull.
 

Woodonglass

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I'd advise a Rip Blsde NOT a fine tooth blade. As I stated previously, the hatches should reveal the depth of your deck and you should set the depth of the saw just slightly deeper than that. Go around the outer edge of the deck with the narrow edge of the saw against the side of the hull. This should yield the same results as the picture you posted.
 

MrCableTek

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So we dug in to her today. I learned some things:
#1: My circular saw is jacked up and can't seem to cut a straight line for ****.
#2: No matter how hard you try or where you put the nozzle of the vacuum dust will end up in your underpants somehow.
#3: A fine toothed saw blade is NOT the correct blade to cut through a fiberglass floor.

I made some rather interesting finds though. First and most importantly, MY STRINGERS ARE FINE! YAY! They're fine because there is ABSOLUTELY NO WOOD IN THEM. They're made of fiberglass and filled with foam which is somehow dry as a bone. So I will not be replacing stringers. This, dear friends, is a good thing because my boat partner (Wayne for future reference) has already had a boat with bad stringers. As a matter of fact, he refused to disconnect the trailer from his truck until we cut out the back to check the transom and stringers due to the previous experience he has had. He was adamant that if we had to gut the hull it was off to the landfill tout suite as not to become another flowerpot in his back yard.

I do, however, have a butt-ton of partially waterlogged flotation / support foam. I need to find out what density it is though. and I'm not sure how other than somehow removing exactly 1 cubic foot of it and weighing it. I need to have someone that knows this stuff actually look at it I guess.

So, an engineering question now. Is there some really good reason that they didn't make some kind of provision for water to escape these cavities as they would almost inevitably get some moisture in them? If it's just to save cost or something, should I then rectify the situation?

Another question, is there some way to seal up the foam to avoid this happening again? I'm imagining the silver bags that are sometimes used in shipping to create custom form-fitting cradles for things inside of boxes but on a larger scale. Imagine if the foam was allowed to expand inside a plastic bag and then sealed. I'm not suggesting that I do this with a kitchen trash bag as I have no idea how this stuff will react with a hefty bag, not to mention that the resulting reaction is exothermic and I would rather not fill my boat up with melted plastic, but you get the idea. Is there a way to accomplish this or should I run over to the patent office tomorrow?

At any rate, here are some photos. 20140907_133753_zpss6bdu67k.jpg
20140907_133415_zpspsbryefa.jpg
And Wayne in full haz-mat gear (minus the goggles). 20140907_115444_zpsy5jzzyfb.jpg

:D
 
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jigngrub

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So, an engineering question now. Is there some really good reason that they didn't make some kind of provision for water to escape these cavities as they would almost inevitably get some moisture in them? If it's just to save cost or something, should I then rectify the situation?

Another question, is there some way to seal up the foam to avoid this happening again? I'm imagining the silver bags that are sometimes used in shipping to create custom form-fitting cradles for things inside of boxes but on a larger scale. Imagine if the foam was allowed to expand inside a plastic bag and then sealed. I'm not suggesting that I do this with a kitchen trash bag as I have no idea how this stuff will react with a hefty bag, not to mention that the resulting reaction is exothermic and I would rather not fill my boat up with melted plastic, but you get the idea. Is there a way to accomplish this or should I run over to the patent office tomorrow?

At any rate, here are some photos.

And Wayne in full haz-mat gear (minus the goggles).

:D

Your foam is 2 lb. density. If it's wet weighing it won't help you determine the density. 2 lb. foam is the most common and widely used.

Water was never supposed to get into the cavities. The deck is supposed to be sealed up waterproof with no penetrations, and the boat is supposed to be kept covered when not in use.

You can remove the wet foam from the cavities and pour new foam flush and smooth with the tops of the stringers and then coat it with marine grade epoxy resin or polyester resin and fiberglass cloth to give it a waterproof cap. The foam is supposed to be firmly bonded/attached to the hull to keep it from floating out of the boat should the boat become swamped... and yes, if not secured to the hull the foam can lift the decking up and float out.

Great news about the stringers and the dry foam in them, that boat is definitely a keeper and well worth a restoration.
 

MrCableTek

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If you will notice in the picture with some of the foam removed that there is no residue remaining against the outer edges of either stringer. This is because the foam is not bonded to the stringers at all. That's how it came out so easily. I slid a prybar down along the stringer and popped it right out.

Matter of fact, I learned something else today. This boat is effectively 3 pieces. The hull and stringers is #1, the deck, bow, gunwales, and cabin is #2, and then there is a top rail that is attached to the top of the gunwales under the rub rail. The deck is attached to the stringers in one big piece using what appears to be Bondo (or some other type of automotive body filling compound). After I cut the floor, I just had to lift at the cut and tug on it once or twice and the whole section lifted out. If this is indeed the case then I absolutely believe you that if this boat did indeed begin to sink, the floor would have busted right off and the hull and engine would have hit the bottom in seconds.

The only issue I have with what you've told me is that the manufacturer obviously didn't care about making the compartments water tight. Nor did they care that the foam would not adhere to the fiberglass structure. And in all my reading everyone seems to keep finding waterlogged foam even in much higher quality boats. It is absolutely impossible to make the compartment itself completely water tight in a boat that is constantly flexing, expanding, and contracting. Maybe the manufacturer just said "Screw it, by the time this rots out it'll be out of warranty anyway.". There must be some solution to this problem for the long term. If the foam were encased on all four sides in something to keep it dry, then a small leak would not be an issue assuming that there was a way for the water to escape to the bilge area.

I'm not an engineer or anything but I know that every time you fight the forces of nature, you will ultimately lose. I'm just trying to find a way to extend the game for as long as possible. If I do this right, my grandkids will be adults before anyone even bothers to check these pockets out. Has anyone out there tried some other method that is better than dumping it right in the pocket and closing it up?
 

jigngrub

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The foam in some boats pops right out, but the foam in most boats sticks with a vengeance. Maybe it's the brand of foam, maybe it's the age of the foam, maybe the foam has been saturated and been through a lot of freeze thaw cycles... but as a rule 2 part expanding urethane foam will stick to everything with a vengeance.

People find water logged foam in their boats because they don't know and understand that the foam will saturate if the boat isn't shown the proper care and maintenance. They leave their boats uncovered and exposed to the elements, they leave the bilge plug in or let leaves and debris accumulate in the boat to stop up the bilge drain and back water up into the bilge, and they don't maintain their deck to keep a waterproof finish and properly seal any penetrations they make in it.

What killed your deck and allowed water intrusion below deck was being exposed to the elements and those pedestal seat bases not being properly sealed. Had your boat been kept covered and protected from the elements your problems wouldn't exist, even with the deck penetrations not being properly sealed. Had everything been sealed up and the boat covered your below deck area would still be like new.

A properly maintained boat will last for generations, and neglected boat is lucky to last one generation (25 yrs.). Most people don't know they have to do certain things to maintain their boat or they know and don't want to take the time or spend the money... and that's why we see so many boats in disrepair. People just want to use a boat for fun and don't want to have to work or spend much effort on it because that isn't fun.

Added:

Most people that take the time and spend the money to restore their boats will realize the value in the proper care and maintenance for a boat and will do what needs to be done to keep their boat from becoming rotten and neglected again... so you have that going for you.
 
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