How can I get the top deck off? Bilge Questions...

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I am in the process of tearing out the floor and stringers in a 15ft Cobia and am at the point where it would be easier to get to everything if the top deck was off. How hard is it to get of and how do you go about removing it and then putting it back on.<br /><br />Also, in planning the new stringers, do I have to use the old layout or can I plan a new design to incorporate a storage compartment etc.<br /><br />I was hoping to re-glass/epoxy the entire hull and then the floor as well so I wouldn't get anymore water in there. So why does every boat have a bilge? Do they plan on the hull failing? How does the water get down there. I want to make it so there is no way for water to seep in.<br /><br />Thanks
 

Realgun

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Re: How can I get the top deck off? Bilge Questions...

So why does every boat have a bilge? When the boat gets wet due to weather or splash the water has to go somewhere. I would rather it drained to the bildge than slosh all around my feet. Also is is easier to drain a bildge than a floor. Just pull the plug!
 

Realgun

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Re: How can I get the top deck off? Bilge Questions...

So why does every boat have a bilge?
When the boat gets wet due to weather or splash the water has to go somewhere. I would rather it drained to the bildge than slosh all around my feet. Also is is easier to drain a bildge than a floor. Just pull the plug!
 
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Re: How can I get the top deck off? Bilge Questions...

Ok,let me re-phrase that... Why does the hull under the floor drain into the bilge. Why not make the hull under there water tight. Then you could spay the floor down and it would drain out the back drain. I'm just wondering why I have to leave a hole from the area under my floor so the water can get to the bilge when I don't want water under my floor. That's why I'm tearing it all out now...
 
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BillP

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Re: How can I get the top deck off? Bilge Questions...

What year is your Cobia? Have any pics of the interior? I have an old 1965 Cobia and redid stringers, floor and transom. New ones are different. The pic looks like an old one. Does yours have a plywood core on the bottom?<br /><br />The square well in the back has drain holes that should be normally plugged (transom type plug). Just take the plugs out if water gets in the bilge from somewhere else and you want to drain it.
 
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Re: How can I get the top deck off? Bilge Questions...

I will be posting some more pics this weekend. Do you have any before/during/after photos of your Cobia. That might help me alot. I don't know what year it is. Can you tell by the hull#? It did have a plywood floor covered with fiberglass before I ripped it out. Did you say you designed your stringers differently on the reconstuction? Mine had 3 long stringers and 3 supports to the sides. How did you change yours and what materials did you use. Pics would be great. Even if you have to e-mail em'.
 

BillP

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Re: How can I get the top deck off? Bilge Questions...

Maybe this won't overload the system. Notice the spashwell is cutout instead of deck removal. There is a ply sheet core with 3 stringers. PT wood throughout.<br /><br />
22mgsj
 

BillP

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Re: How can I get the top deck off? Bilge Questions...

Here's the bare hull. I put the stringers in before cutting splashwell and transom out so the boat would stay aligned easier. <br /><br />
22miqs
<br /><br /><br />This shows the 1/2" plywood bottom core (which was original construction). The orginal was good but I couldn't tell for sure without tearing it out. After 30+ yrs the core in this application is proven to work beyond doubt. Hard to see the side stringers but there are 3 stringers. Center is 12" dimensional plank cut to fit and sides stringers are 3/4" ply. Originals were 2x dimensional spruce. The cross pieces are for leveling and to hold down the stringers until glassed. The white "stuff" is thickened epoxy to glue them down and gap fill.<br />
22miah
<br /><br /><br />The cut out splashwell...easier to cut and glass back than take the deck off. This boat deck was glassed and through bolted, which means cutting the hull to get them apart. Major PITA trying to align and glass them back.<br /><br />
22napu
<br /><br /><br />
22nbsl
<br />
22nc5i
 

Bondo

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Re: How can I get the top deck off? Bilge Questions...

Cool Looking Boat.................. ;)
 
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Re: How can I get the top deck off? Bilge Questions...

Very nice... You just got me motivated to get this thing done!!! I started looking at new fish & ski boats today... It just seems like it is taking so long. I just want to get on the water by summer!<br /><br />Thanks for the pics!
 
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Re: How can I get the top deck off? Bilge Questions...

Bill one more thing... What did you do to hull's exterior? Extra glass or epoxy and what paint did you use. That's a perfect color!
 

Realgun

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Re: How can I get the top deck off? Bilge Questions...

While not a perfect color it looks awsome on your boat. I want a red stipe. I found out that the striping is awful expensive!
 

BillP

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Re: How can I get the top deck off? Bilge Questions...

It had faded red gelcoat when I bought it around 1985. Later I painted it a dark blue Brightsides. The first pic shows what 10+ yrs in Florida sun does to it...Brightsides is durable stuff. Last color is Brightsides CC Blue (ChrisCraft Blue). I compounded (no sanding)the hull to get it clean and rolled/tipped the CC Blue. It shows brushmarks up close but at 5' away it looks smooth like gelcoat. Its a daily driver so I didn't spend much time on cosmetic prep.<br /><br />Here's a pic showing how small it really is...17'<br />
231qnk
 

Richard Petersen

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Re: How can I get the top deck off? Bilge Questions...

I am going to give the wood boat that black caulk look between each deck board by using, black, auto body shop pin stripping vinyl tape and varnish. They have colors.
 

Richard Petersen

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Re: How can I get the top deck off? Bilge Questions...

If you do take the deck off. FIRST firmly support the bottom of the boat with long lumber to keep the shape when the deck is off and you are standing inside working.
 

BillP

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Re: How can I get the top deck off? Bilge Questions...

Glassing in stringers and/or floor before you remove the deck will be a big help in keeping it aligned. Bare hulls have a lot of flex.
 

JasonJ

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Re: How can I get the top deck off? Bilge Questions...

Bill, I never realized that boat was that small. I have seen pics of it before, I always thought it was 19+ feet. Cool boat...<br /><br />Old Cobia, I pulled the top on mine, it was a pain, but not that bad. I like Billp's splashwell trick, but unfortunately it would not have worked for me as my hull was a bowrider and the entire front seating area was integral to the upper half and I needed to get under it for the rebuild. If you do decided to pull the top, you'll need to remove everything, windshields, all of it to reduce weight and stress. Then you'll need to remove the rubrail, followed by the screws that hold the rubrail bracket on. The splashwell will probably be bonded to the transom, but a prybar will pop that loose. Hopefully the upper is not glassed to the lower. You can lift it off with a few buddies, it isn't that heavy.<br /><br />I left my hull on my roller trailer, and glassed in one stringer at a time, checking alignment along the way. The hull shell was very strong and stable once I have my six stringers in, but it was pretty flexy without the structure. It is doable as long as you pay attention to the hull bottom and watch for hooks, bows, and warps. Good luck...
 

Solittle

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Re: How can I get the top deck off? Bilge Questions...

Thank you for keeping one of the "old timers" sliding over the water. I had the 17' version of that boat many years ago.
 
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