Reinstalling under deck buoyancy?

[footsoldier]

So theoretically could i use the foam...tip the bow down and stern up and pour from stern hatch and allow it to slowly run forward.

Once it has filled up the aft half of the boat tip the bow up on jockey wheel and pour from bow down until it flows out of bow hatch creating a join of foam in the middle?

I would be very wary of your notion of allow it to slowly run forward. From my limited experience - and not in this sort of application - it does not flow very readily, it expands as soon as it is exposed and blocks any further access to the space. I would experiment first with its flow (or not!) qualities somewhere non-critical.

 

[PilotWolf]

You’re probably not going to like this...

Its piss poor planning.

You knew that there was foam there before as you removed it. You laid a new deck without replacing it first. The company that laid the deck should IMHO have asked the question too before laying the deck.

Anything you do now is going to be a compromise. The foam is the obvious choice as replacing like for like. Can the decking company not help? A professional company should have the capability to fill the void without causing damage or having to drill the new deck.

All the other suggestions other than maybe the airbags which of course have their own problems are again IMHO no more than a bodge.

The only other option than has just come to mind is what about polystyrene beads poured into the spaces? But of course anything not solid will cause an issue if you get any water in there that needs to be removed.

It might be the time to swallow the pride (yes I do know how hard that is), and get professional help involved to resolve the problem. After all you’ve invested a lot in the boat and you don’t want to lose it

PW

 

[MystyBlue2]

You’re probably not going to like this...

Its piss poor planning

You knew there was foam there before as you removed it. You laid a new deck without replacing it first. The company that laid the deck should IMHO have asked the question too before laying the deck.

Anything you do now is going to be a compromise. The foam is the obvious choice as replacing like for like. Can the decking company not help? A professional company should have the capability to fill the void without causing damage or having to drill the new deck.

All the other suggestions other than maybe the airbags which of course have their own problems are again IMHO no more than a bodge.

The only other option than has just come to mind is what about polystyrene beads poured into the spaces? But of course anything not solid will cause an issue if you get any water in there that needs to be removed.

It might be the time to swallow the pride (yes I do know how hard that is), and get professional help involved to resolve the problem. After all you’ve invested a lot in the boat and you don’t want to lose it

PW

I did the deck myself with marine ply and fibreglass...i opted out of reinstalling the foam as it was the reason for the soggy deck and 200kg of water weight it had absorbed to begin with.

I vowed when i replaced the deck to NEVER have that same issue in the future as the foam is ok if kept dry and new...once older and wet its a new deck all over again so i made my decision on the very fact that it had caused me a huge headache and emptied my bank account for the sake of foam. So even the boat manufacturers way of creating buoyancy isn't 100% practical either.

 

[TernVI]

The compartments are seperate as the deck is sitting ontop of the chines as support so if you cut the transom off and look through ul see a M shape (chines) and deck sitting ontop seperating each chamber.

Its not a sealed air compartment as i have installed inspection hatches so if i did get a leak from D ring, chip in keel etc i could see how bad it was and start bilging it out. But because of that ive opened myself up to the possibility of filling underdeck with water and sinking.

I know the Titanic sank despite having several watertight compartments, but if you have 3 compartments which are not going to fill quickly from a small hole, minor hatch leaks etc, I'd say your boat was OK. The kind of thing I'd want a Dory to survive is maybe putting a small hole it in, or getting swamped by bad waves or wash from another boat. So long as your hatches don't let tens of gallons in, you are fine IMHO.
No small boat is indestructable.
Your hull is probably pretty tough and hard to hole compared with the sailing dinghies I race.

I have seen too many Dory-type boats full of soggy foam. I never want to see another one!

Would your boat float with the under-deck flooded, like a Searider?

 

[MystyBlue2]

I know the Titanic sank despite having several watertight compartments, but if you have 3 compartments which are not going to fill quickly from a small hole, minor hatch leaks etc, I'd say your boat was OK. The kind of thing I'd want a Dory to survive is maybe putting a small hole it in, or getting swamped by bad waves or wash from another boat. So long as your hatches don't let tens of gallons in, you are fine IMHO.
No small boat is indestructable.
Your hull is probably pretty tough and hard to hole compared with the sailing dinghies I race.

I have seen too many Dory-type boats full of soggy foam. I never want to see another one!

Would your boat float with the under-deck flooded, like a Searider?

With all gear onboard engine and such it probably would sink if i got a hole in the hull.

Thats why i opted out of the foam when i renewed my deck so now i can keep an eye in any leaks and atleast now i can throw a bilge pump into deck hatch and pump out whilst underway back to harbour. With the foam in, its sort of pot luck as to finding the damage. Then ofcourse lifting up the whole deck and foam to repair it.

Brand new boat from factory yes! But an old boat with foam gives you more headache than its worth IMHO.

im leaning more toward buying new hatches with new seals, using polyurethane sealant and creating a sealed buoyancy chamber under deck.

And because there is no foam i can periodically open hatches and check for leaks and if i see water i can motor back to harbour as the bilge pump it disposing of water under deck.

Aslong as i have new seals on deck hatches theoretically it should be one big air bladder under deck...until the hull gets holed that is.

 

[duncan99210]

As Tern says, you’ve already got buoyancy built into the boat in the form of the void under the deck. Check the seals on the current hatches, replace if you feel it really necessary but I probably wouldn’t bother. I would be very wary of using foam to fill in the voids for the very reason you encountered when fitting the new deck. If you’re really worried about things, then either PET bottles or dinghy type buoyancy bags is the way to go but I think either is OTT.
Different question is proposed usage. At 14 foot the boat is fairly small but provided you don’t overload her, going reasonably far offshore isn’t impossible but more important than the kit you carry is the knowledge you have. Pay attention to the weather forecast and be prepared to change or cancel your plans if the forecast isn’t calm enough. Otherwise, enjoy.

 

[MystyBlue2]

As Tern says, you’ve already got buoyancy built into the boat in the form of the void under the deck. Check the seals on the current hatches, replace if you feel it really necessary but I probably wouldn’t bother. I would be very wary of using foam to fill in the voids for the very reason you encountered when fitting the new deck. If you’re really worried about things, then either PET bottles or dinghy type buoyancy bags is the way to go but I think either is OTT.
Different question is proposed usage. At 14 foot the boat is fairly small but provided you don’t overload her, going reasonably far offshore isn’t impossible but more important than the kit you carry is the knowledge you have. Pay attention to the weather forecast and be prepared to change or cancel your plans if the forecast isn’t calm enough. Otherwise, enjoy.

BRILLIANT! problem solved then! Im a pussy when it comes to the sea and i have no confidence at all!

So basically if its not glassy calm and going to stay that way i stick to the motto of "If in doubt...Dont go out"

Theres always another day so if i do get cought out, Which can happen to anybody on any size boat, Then its down to pure bad luck not down to overconfidence and incompetence.

Im not going to be the next headline or be another statistic at sea.

I keep a very close eye on weather and tides and all my trips so far have been cut short by my own lack of confidence on the off chance im pushing my luck.

 

[TernVI]

It would not be a very big job to cut out a big section of the deck, glass in some partitioning of the under deck space and re-instate.
But a few rubble sacks and a few cans of builders' foam is obviously easier.

 

[PaulRainbow]

BRILLIANT! problem solved then! Im a pussy when it comes to the sea and i have no confidence at all!

I doubt this thread and your other has helped your confidence.

This was completely possibly the wrong forum to ask either of your questions, IMO. It's populated with sailboat owners mostly, who look at things differently to anyone that owns something like your boat. I come from a motor boat background, but now have a 35ft sail boat, i do not carry as much safety equipment as has been suggested for your boat, i don't have an aux engine (never owned one) and my boat has no foam filled buoyant compartments, if i bash a hole in it, it's going to do what the vast majority of the boats on here will do, sink. (no need for any Sadler et al owners to jump up )

World Sea Fishing is populated by loads of people like you, with boats like yours, who go several miles offshore fishing, they don't all sink and die. No disrespect to those who have answered, they have all done so with the best intentions.

In your shoes, i'd see if the under deck compartments are water tight, if they are you have your buoyancy.

If not, i'd see if i could make then water tight. If i couldn't, i'd fit 2 or 3 of the water tight hatches i linked to in the other thread and fill the void with play pit balls, loads of the WSF guys have done this over the years. Cheap, quick and easy to do, with no chance of damaging anything with expanding foam.

Why bother with buoyancy ? A big wave/wash over the transom could swamp you, with no buoyancy you could sink fast. Buoyancy might just keep the boat afloat enough to pump out and recover.

 

[MystyBlue2]

I doubt this thread and your other has helped your confidence.

This was completely the wrong forum to ask either of your questions, IMO. It's populated with sailboat owners mostly, who look at things differently to anyone that owns something like your boat. I come from a motor boat background, but now have a 35ft sail boat, i do not carry as much safety equipment as has been suggested for your boat, i don't have an aux engine (never owned one) and my boat has no foam filled buoyant compartments, if i bash a hole in it, it's going to do what the vast majority of the boats on here will do, sink. (no need for any Sadler et al owners to jump up )

World Sea Fishing is populated by loads of people like you, with boats like yours, who go several miles offshore fishing, they don't all sink and die. No disrespect to those who have answered, they have all done so with the best intentions.

In your shoes, i'd see if the under deck compartments are water tight, if they are you have your buoyancy.

If not, i'd see if i could make then water tight. If i couldn't, i'd fit 2 or 3 of the water tight hatches i linked to in the other thread and fill the void with play pit balls, loads of the WSF guys have done this over the years. Cheap, quick and easy to do, with no chance of damaging anything with expanding foam.

Why bother with buoyancy ? A big wave/wash over the transom could swamp you, with no buoyancy you could sink fast. Buoyancy might just keep the boat afloat enough to pump out and recover.

Cleared that up alot!

Thank you very much for all your help and to everybody who has commented.

I've learned alot on this forum and all your knowledge is second to none!

Thank you all so much its all very much appreciated ?

 

[AntarcticPilot]

I doubt this thread and your other has helped your confidence.

This was completely possibly the wrong forum to ask either of your questions, IMO. It's populated with sailboat owners mostly, who look at things differently to anyone that owns something like your boat. I come from a motor boat background, but now have a 35ft sail boat, i do not carry as much safety equipment as has been suggested for your boat, i don't have an aux engine (never owned one) and my boat has no foam filled buoyant compartments, if i bash a hole in it, it's going to do what the vast majority of the boats on here will do, sink. (no need for any Sadler et al owners to jump up )

World Sea Fishing is populated by loads of people like you, with boats like yours, who go several miles offshore fishing, they don't all sink and die. No disrespect to those who have answered, they have all done so with the best intentions.

In your shoes, i'd see if the under deck compartments are water tight, if they are you have your buoyancy.

If not, i'd see if i could make then water tight. If i couldn't, i'd fit 2 or 3 of the water tight hatches i linked to in the other thread and fill the void with play pit balls, loads of the WSF guys have done this over the years. Cheap, quick and easy to do, with no chance of damaging anything with expanding foam.

Why bother with buoyancy ? A big wave/wash over the transom could swamp you, with no buoyancy you could sink fast. Buoyancy might just keep the boat afloat enough to pump out and recover.

And it's worth noting that any foam, bottles, ball pool balls, buoyancy bags or whatever will have LESS buoyancy than an empty, sealed space; closed cell foam especially is surprisingly heavy. The reason for foam or whatever is to ensure that a breach in the hull doesn't result in the entire loss of the buoyancy, not to add buoyancy. If you can subdivide the space, then that would achieve the same result - and a few buoyancy bags would do that for you at less reduction in initial buoyancy than most other solutions. I'd put foam down as the least desirable method, only to be considered if there's really no other way.

 

[MystyBlue2]

And it's worth noting that any foam, bottles, ball pool balls, buoyancy bags or whatever will have LESS buoyancy than an empty, sealed space; closed cell foam especially is surprisingly heavy. The reason for foam or whatever is to ensure that a breach in the hull doesn't result in the entire loss of the buoyancy, not to add buoyancy. If you can subdivide the space, then that would achieve the same result - and a few buoyancy bags would do that for you at less reduction in initial buoyancy than most other solutions. I'd put foam down as the least desirable method, only to be considered if there's really no other way.

Think im going to replace my deck hatches with complete new ones as they are a little shabby anyways and to ensure a brand new rubber air tight seal. Then screw and polyurethane sealant adhesive to bung them down with and create a seal around the base.

Secondly replace all 3 bungs on transom to ensure no water can leak past and compromise the chamber,

Thirdly reseal my D ring on bow to ensure no water can leak past into the hull

And last...with bungs in tight and deck hatches closed...spray a soapy liquid around the deck and around the seams where i glassed the deck in, And around the bilge and bounce up and down on the deck, if any pin holes are present then i will see bubbles forming so i can mark it and repair it.

Final result i should have a complete airtight chamber the full length of the boat and as long as i dont hit a rock or bottom out it should provide me with the maximum buoyancy at no added weight.

Also fitting an electric bilge pump that can be moved from top deck bilge to inside the stern hatch (under deck) so i can bilge any water if i do get a leak.

So if the hull is airtight, And i do get a wave/wake over the stern the buoyancy of the hull will support the weight of the water until my electric bilge pump can remove it rather than it weighing me down resulting in total swamping and sinking.

Total cost £60 for new hatches and bungs.

£30 elec bilge pump.

Well worth it.

Thanks to everyone that has commented and given me top quality advice. Every day is a school day and I've learned alot! Your knowledge is worth its weight in gold. Thanks so much ?

 

[rogerthebodger]

I had to use silicon grease on my hatch O ring to ensure a air/water seal.

I would also have a manual bilge pump incase the electrics get swamped.

 

[MystyBlue2]

I had to use silicon grease on my hatch O ring to ensure a air/water seal.

I would also have a manual bilge pump incase the electrics get swamped.

Nice tip would ramonol white grease do the job?

I've got a manual pump thats the one i have aboard at the moment

 

[PaulRainbow]

Nice tip would ramonol white grease do the job?

Yes.

I think your plan in post #32 is spot on

 

[MystyBlue2]

Yes.

I think your plan in post #32 is spot on

Thank you very much ? looking forward to the work and boating season now ?

 

[Rappey]

I look out my window and see many hundreds of small open and cuddy cabin boats on moorings.
What nearly always happens every time a small boat "sinks" (usually from not being bailed out) is that it flips over , the stern goes down under the weight of the engine but the bow retains a decent air pocket inside and this stops the boat going to the bottom, providing it has at least a small front deck..
A sealed void under your floor is more than what most boats have so your already at an advantage over most.
The 2nd most popular reason for boats sinking while moored are fitting elephants trunks or any other after thought of a self draining system !
Mines just over 15ft, cat C so suitable for up to 2m waves and force 6, 27 knts of wind.. and its completely open as its a bow rider, but its also self draining by design and high freeboard (sides)
Its fairly scary in those conditions in the solent as waves are steeper than in an open sea but being sensible there is no drama.

 

[MystyBlue2]

I look out my window and see many hundreds of small open and cuddy cabin boats on moorings.
What nearly always happens every time a small boat "sinks" (usually from not being bailed out) is that it flips over , the stern goes down under the weight of the engine but the bow retains a decent air pocket inside and this stops the boat going to the bottom, providing it has at least a small front deck..
A sealed void under your floor is more than what most boats have so your already at an advantage over most.
The 2nd most popular reason for boats sinking while moored are fitting elephants trunks or any other after thought of a self draining system !

Ah is that that type of deck self drain trunk that folds up onto transom and "drains the deck" when motoring?

I've seen them fitted to RIBS and I'm definitely a sceptic...i personally wouldn't fit one to my boat.

Aslong as i have means to bilge water out top deck if a wave comes in/wake etc and below deck is an airtight buoyancy chamber then i think I've done everything practically possible to be safe,

Like stated earlier in the thread...now its down to the power of knowledge of tides, weather and a sprinkle of common sense...i cant wait to start using my boat for its intended use rather than hugging the coast line and being too scared to venture more than 500yards from harbour. Baby steps but time to relax and enjoy my boat this season.

 

[MystyBlue2]

Mines just over 15ft, cat C so suitable for up to 2m waves and force 6, 27 knts of wind.. and its completely open as its a bow rider, but its also self draining by design and high freeboard (sides)
Its fairly scary in those conditions in the solent as waves are steeper than in an open sea but being sensible there is no drama.

So by the look of mine...honestly opinion what would you rate it at?

Wind...
Wave height...
Estimated CAT etc...

I dont know the specs or anything as the plaque has been removed by previous owner and ive messaged seahog to find out the exact specs and no bloomin reply and cant find any info online either...cheers mate ?

 

[Rappey]

It might be to old to have a category but googling it i see its a very popular fishing boat and seen youtube boat with up to 60 hp, 3 up.. Could guess it would be similar to a cat C as motoring forwards the cabin will protect the cockpit from waves and it looks extremely buoyant.. Its something that they are still made, must be due to popularity.
A rubbish boat would not be popular for long !

This is what i have and a F6 doesnt seem to overwhelm the boat..