Installing Hardware Below the Waterline

Ogden2

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Jun 28, 2012
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Hello. Would it be a good idea to drill holes through the transom which are slightly larger than the screws for my swim platform's lower mount (below the waterline), fill the holes with epoxy and then drive the screws into the epoxy when mounting? It seems that this way it would be less likely for water to get into the transom wood. I'm debating on whether or not to do this before I pour my foam and seal off the deck. Thoughts?
 

Georgesalmon

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Re: Installing Hardware Below the Waterline

IMHO epoxy would be a poor choice unless you drill an oversize hole and fill with epoxy and then drill the right size hole and use an underwater sealant such as 3M 5200 to do the sealing around the screw/bolt. You need a flexible sealant for that not a hard one that could crack from the stress of the screw threads. A good job with a good sealant will keep water out with out the extra work.
 

Ogden2

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Re: Installing Hardware Below the Waterline

IMHO epoxy would be a poor choice unless you drill an oversize hole and fill with epoxy and then drill the right size hole and use an underwater sealant such as 3M 5200 to do the sealing around the screw/bolt. You need a flexible sealant for that not a hard one that could crack from the stress of the screw threads. A good job with a good sealant will keep water out with out the extra work.

Thanks for your reply.

Yes, what I had planned is to drill an over-sized hole and fill that with epoxy to basically replace the material (hull and transom wood) that was drilled out. Then I would mount the hardware as usual by drilling a pilot hole into the epoxy for the screws, and then using the 3M 5200 to seal the screw. It just seems that the epoxy core will give a little buffer zone to make it harder for water to reach the transom wood should the 5200 seal ever break down.
 

sqbtr

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Re: Installing Hardware Below the Waterline

If you are through bolting I would say yes, oversize, fill and through drill and seal with 5200. If you are using screws, I wouldn't think the screw would hold as well in the epoxy, especially for a swim deck.
 

Fishin Magician

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Re: Installing Hardware Below the Waterline

Hello. Would it be a good idea to drill holes through the transom which are slightly larger than the screws for my swim platform's lower mount (below the waterline), fill the holes with epoxy and then drive the screws into the epoxy when mounting? It seems that this way it would be less likely for water to get into the transom wood. I'm debating on whether or not to do this before I pour my foam and seal off the deck. Thoughts?

huh.................what kind of drill ya got that runs under water.??
:D

FM
 

Ogden2

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Re: Installing Hardware Below the Waterline

If you are through bolting I would say yes, oversize, fill and through drill and seal with 5200. If you are using screws, I wouldn't think the screw would hold as well in the epoxy, especially for a swim deck.

I thought so too, but was trying to weigh the pros and cons of both. Also thinking of upgrading the swim platform to bolts instead of screws, even though they are fairly hefty screws. This is what the boat looked like about a week ago and you can see the two bottom screws will be just below the floor (roughly), so since I am planning on pouring the foam and affixing the deck by the weekend's end, if I am to do something differently than simply screwing them in as they were, I need to do it now.

17-inner-transom-plate-2-small.jpg

huh.................what kind of drill ya got that runs under water.??
:D

FM

An underwater drill, that's a good idea. hmmmm...
 

Georgesalmon

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Re: Installing Hardware Below the Waterline

If you ever have a problem you'll wish you used screws. Eventually the bolt will loosen from crushing the transom over a long time with pressure on it. They all do. Normally I'm a bolt guy for everything but this one bothers me because I couldn't get to both sides..
 

Fishin Magician

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Re: Installing Hardware Below the Waterline

Ogden2 ...your quote......" the screws for my swim platform's lower mount (below the waterline), "

Funny thing is... few yrs back someone was using the swim platform on my searay and while climbing out he ripped one of the chrome handles right out of the back of the boat...thank god he didn't drop it....boat was docked in water for the season at a friends place... for free... and I didn't want to pull it out t....figured I would wait to fix it.....I caught a lot of slack from the boss about her not being able to use the platform for fear it would brake the other side...my excuse to her was that... If she could find me a drill that works underwater...I would fix it for her.......

so yeah ...let's be the first to develope that Idea......don't tell anyone though...secret..
FM
 

Woodonglass

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Re: Installing Hardware Below the Waterline

If you ever have a problem you'll wish you used screws. Eventually the bolt will loosen from crushing the transom over a long time with pressure on it. They all do. Normally I'm a bolt guy for everything but this one bothers me because I couldn't get to both sides..
If the transom is sealed properly and maintained properly and water is not allow to intruded the Bolts will NOT crush the transom. It will be as solid 10 years from now as it is today. My transom is 51 yrs old and solid as the day it was installed. Epoxy has "Binders" in the resin which keeps it from cracking but it does not have UV protection so it does require protection. Through bolting for ladders IS the preferred method IMHO and oversized hole drilling is too. I would recommend using "Hairy Peanut Butter" as the filler" Much better and stronger IMHO. and allows you to gelcoat if you so desire. Epoxy does not like gelcoat, some say you can gelcoat over it but other say no. I stay with poly just so I'm sure to have no issues.
 

Ogden2

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Re: Installing Hardware Below the Waterline

so yeah ...let's be the first to develope that Idea......don't tell anyone though...secret..
FM

Already started working on it :0


If the transom is sealed properly and maintained properly and water is not allow to intruded the Bolts will NOT crush the transom. It will be as solid 10 years from now as it is today. My transom is 51 yrs old and solid as the day it was installed. Epoxy has "Binders" in the resin which keeps it from cracking but it does not have UV protection so it does require protection. Through bolting for ladders IS the preferred method IMHO and oversized hole drilling is too. I would recommend using "Hairy Peanut Butter" as the filler" Much better and stronger IMHO. and allows you to gelcoat if you so desire. Epoxy does not like gelcoat, some say you can gelcoat over it but other say no. I stay with poly just so I'm sure to have no issues.

Well that's good because I'm using poly and absolutely love peanut butter, so I believe I will do that. Thanks.
 

Woodonglass

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Re: Installing Hardware Below the Waterline

Hairy Peanut butter is Resin, Cabosil, and finely cut up scraps of CSM and Or Fiberglass cloth srtands, 1.5% MEKP, and mixed to the consistency of Creamy Peanut butter.
 

belairbrian

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Re: Installing Hardware Below the Waterline

Sorry guys, they already make underwater drills. They run of compressed air.
 

Fishin Magician

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Re: Installing Hardware Below the Waterline

Sorry guys, they already make underwater drills. They run of compressed air.

yeah.... I thought about that after I hit enter...hehe..
probly use extensions with universal's too .....
or ..like I said ....do it when it's out of the water......

the ability to do quick fixes at low cost for " portable under water drill "....how's that ??

FM
 

Ogden2

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Re: Installing Hardware Below the Waterline

Hairy Peanut butter is Resin, Cabosil, and finely cut up scraps of CSM and Or Fiberglass cloth srtands, 1.5% MEKP, and mixed to the consistency of Creamy Peanut butter.

Oh, yes, I actually meant that literally, I love "peanut butter" a.k.a. polyester resin, chopped strands, MEKP and a lot of fumed silica. I tried it with wood flour on part of my project and I was cursing myself silly.

This is my new transom as the peanut butter still hadn't kicked off yet (taken 2012/08/13).

peanut-butter-transom-small.png



Sorry guys, they already make underwater drills. They run of compressed air.

So I'll withdraw my submission to the USPTO. :D
 

Fishin Magician

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Re: Installing Hardware Below the Waterline

withdraw my submission to the USPTO. :D[/QUOTE]

hold on...I think we may have somethin here...:cool:
 

jbcurt00

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Re: Installing Hardware Below the Waterline

As the OP of this thread, I'll reply to your question here:
Why do I have to pour the foam through drilled out holes in the deck? Can't I lay the deck down after I have poured the foam?

If you look at a cured chunk of closed cell poured in foam, it's got a hard outer shell that's basically smooth and should resist water intrusion better then if you cut the top off of a cured chunk of flotation foam & expose the expanded foam interior. To some degree this removes a fraction of the encapsulated air volume trapped in the foam. It's the air trapped in the foam that's providing the flotation.

EDIT: Many manufacturers depend on the expanded foams expansion into every nook & cranny below decks and it's adhesion to those surfaces, as an integral portion of the structural components of the hull & deck.

NOTE: If the OP (original poster as noted by the [OP] next to their user name) hasn't posted anything in a thread for 3months, it's best to treat them as dead threads & for research only. Try not to post into them. If you have specific questions about the OP's boat, topic or thread, you might PM the OP, perhaps they will respond.
As boating season winds down, more people are considering some boat maintenance this winter, so there have been a bunch of old threads brought 'back'. Once there's been a new post, the thread goes back to the top of the recent post list, and there are many subsequent posts... And although the discussion may prove helpful to some, it would be of much greater benefit, to more iboaters, if it occurred in a relevant and recently started thread.


And now back to your hardware below the waterline thread....:)

BTW: Might consider starting a maintenance thread about your boat & what you're doing. And post up some pix. Plenty of pix junkies around these parts
 
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Yacht Dr.

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Re: Installing Hardware Below the Waterline

LOL .. I have installed 2" through hull fittings with an Air driven drill Via snorkel.

Even off a scuba tank ..

The sealants work great under these conditions ..

YD.
 

belairbrian

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Re: Installing Hardware Below the Waterline

LOL .. I have installed 2" through hull fittings with an Air driven drill Via snorkel.

Even off a scuba tank ..

The sealants work great under these conditions ..

YD.

How did you hook the drill to the snorkel? :D
 
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