Deck repair for seats?

[Dannal]

Hey all. I am absolutely new to the world of boats and have encountered an issue I believe would be best answered by the type of people who woule be a part of this community. Knowing that I am very new, I will also apologise in advance for any names, terms, etc, I simply don't know the name of. Here goes.

I purchased a 1993 14' Swiftcraft Sea Otter a few months ago and am at the point where it is ready for the water. I believe the previous owner knew even less than I do and appears he has carried out some "work" to the boat prior to me purchasing it. The current problem I need help with is the deck/floor. The 2 pedestal seats have round bases and 6 screw holes to secure them to the floor. However, I had a suspicion the seats were merely screwed into the fibreglass floor and didn't have any type or reinforcement below the floor. This was confirmed when my chubby butt took a clumsy tumble and tore the seat screws out when I tried to save myself by grabbing the seat.

I have an idea about cutting a section of the deck out on both sides in an areas larger than the seat bases would sit, then adding some epoxy treated plywood under the deck spanning in a larger area than the goles created, fibreglassing them into place, and then sealing it shut with more fibreglass. According to my thinking, this would give the seat screws something strong to anchor to and provide more strength for the stresses the seat and deck joining will have to endure when boating in rough waters.

I have no illusions about my lack of knowledge and capabilities, so please feel free to give me your thoughts in regards to whether my idea is sound, or if you would scrap that idea because you know a better way and can tell me.

Cheers, Dan

 

[redneck joe]

welcome to the forum.


i think you plan is workable. I am a fan of T-nuts. You can maybe even just cut a hole large enough to get your hand in and use existing holes if the wood is still good.

 

[Dannal]

Damn, that has opened up another line of thinking for me, Thanks Joe. Perhaps if I can make up a rectangle piece of plywood with the centre cut out and then cut it down the centre, I could figure outwhere the screws would line up and attach T-nuts to the under-side before fibreglassing it in.

Being a bigger bloke, I don't want to have to worry about dedstroying the floor every time I hit a wave lol

 

[froggy1150]

When I redid my boat I wanted ZERO penetrations into the floor. What i did was after I glassed the floor before gelcoat I cut plywood pedestal base mounts that were almost as wide as where the seats went, drilled and installed stainless t nuts. Then I taped off the tnut holes to keep them clean. Then I glued them down with resin mixed with 1/4" chopped glass mixed in and then I tabbed and glassed over the base. I have a stable seat mount that won't pull out and no water can get to foam cavity.

 

[bakerjw]

Being that it is a 33 year old boat, there could be gremlins lurking below the decks. Most are in this subforum because of that at one time or another.

Froggy has a good design there. Make sure that you seal the existing holes before proceeding and seal seal seal. Water getting into places where it is not designed to go is always a bad things.

Once all in place, you might even pick up a gallon of white gelcoat and recoat the entire deck to match.

 

[Scott Danforth]

not sure what core material is in the floor or what is under the seat bases.

we have seen people drill holes into fuel tanks, etc. I have personally screwed into under deck plumbing

Here is what I would do

drill the holes where the screws go to 3/8". you just want to go thru the top layer of glass down about 3/8. if the shavings are wet, you are into a restoration and the floor is coming out if the shavings are dry, then continue.

then chuck up a 1/8" allen wrench in a cordless drill.
in each hole, chew out the coring
vacuum out the chewed up coring.
mix up some PB (see the stickies). fill the voids and let cure
then drill your pilot holes for the screws. it will hold as long as the rest of the deck is not rotten.

alternately, the top-mount that @froggy1150 posted is what I did for the tower mount because I built coolers under my floor in 2011 and didnt want to drill into them.

other people have used toggle bolts on some decks. there are stainless toggle bolts that have the little plastic retainers to hold the threaded portion under the deck while the epoxy/methacrylate/resin cures.

below is from mcmaster carr which is half of what the marine shops sell it for (because they get them from mcmaster carr)

 

[Chris1956]

I have never tried these, but they are stainless steel which is essential. Garelick is a good name as well.

Garelick Stainless Steel Toggle Bolt Anchors 6pk

Positively secures seats and table bases to decks or any accessory to cabin walls. Made of 304 Stainless Steel.

www.wholesalemarine.com

 

[JASinIL2006]

I went a similar route to what Froggy took. You can check it out in my resto thread (https://forums.iboats.com/threads/t...rson-186-sei-i-o-bowrider.552555/post-3970663) starting around post #92 and discussed on and off to post #141. Like Froggy, I didn't want any thru-deck fasteners if I could avoid it.

I used stainless steel T-nuts buried into the bottom of the bases; the bases were then peanut buttered to the deck and then glassed in. They are quite strong and have help up extremely well.