I'm restoring a Catalina 1977, how do you get the water out of these compartments? Has anyone removed the foam and not replace it?
Water in compartments with foam
- Thread starter ingramsail
- Start date
Sure.
Not I, but that is a common problem on trailer sized boats, including my Mariner 19. A number of Mariner owners have done that. Others drill holes to let drain into low spots in the bilges or tilt the trailer. This can take days and days to stop flowing. Others cut access ports into the foam filled space and replace the foam.
I'm of the removal and close up tight with a waterproof access port type, myself. I like the idea of foam where the area can't be watertight, but these spaces under the 'V' berth, for example, can also make good storage areas, as well as floatation chambers.
-Will (Dragonfly)
Not I, but that is a common problem on trailer sized boats, including my Mariner 19. A number of Mariner owners have done that. Others drill holes to let drain into low spots in the bilges or tilt the trailer. This can take days and days to stop flowing. Others cut access ports into the foam filled space and replace the foam.
I'm of the removal and close up tight with a waterproof access port type, myself. I like the idea of foam where the area can't be watertight, but these spaces under the 'V' berth, for example, can also make good storage areas, as well as floatation chambers.
-Will (Dragonfly)
comments above noted...
Other posts read as well as other threads on this topic and the topics of boats coming to grief and sinking (for whatever reasons). Since I have been literally rebuilding my boat from the bottom up I was considering the "make it unsinkable" route... Under the v-berth forward, each side miships inside the inner lining that forms the shelf down into the storage lockers, under the cockpit floor, under the "1/4" berth / sliding galley stowage and corresponding space in the port aft storage...
Foam for floatation... My take on that is: keep the cockpit lockers' lids shut and secured, put the washboards in place and the close the hatches when it's rough/raining, don't run into hole making rocks, pay attention to where the boat is going... have life jackets for when it gets hairy, etc. = no need for floatation foam.
Every 1000kg of boat would require 1000 ltrs of floatation... and thats the bare minimum. Even foam only gives you an 85 to 90% bouyancy for the volume filled. Using plastic bottles and you're down to less than 60%!
It's quite difficult to fit all that foam and not run out of decent storage place. That foam would obviously need to be low down and well spread out to provide a stable upright floating platform = this means taking up very valuable storage spaces. No point in the thing floating on it's side or upside down!
Very open debate on this topic with lots of varied ideas / opinions.
So foam enclosed in poorly constructed enclosures provides for rotting water storage!
Water tight is only water tight if there are no leacks, cracks or holes.... So keep the hull free from cracks or holes and it will float forever all by itself!
Other posts read as well as other threads on this topic and the topics of boats coming to grief and sinking (for whatever reasons). Since I have been literally rebuilding my boat from the bottom up I was considering the "make it unsinkable" route... Under the v-berth forward, each side miships inside the inner lining that forms the shelf down into the storage lockers, under the cockpit floor, under the "1/4" berth / sliding galley stowage and corresponding space in the port aft storage...
Foam for floatation... My take on that is: keep the cockpit lockers' lids shut and secured, put the washboards in place and the close the hatches when it's rough/raining, don't run into hole making rocks, pay attention to where the boat is going... have life jackets for when it gets hairy, etc. = no need for floatation foam.
Every 1000kg of boat would require 1000 ltrs of floatation... and thats the bare minimum. Even foam only gives you an 85 to 90% bouyancy for the volume filled. Using plastic bottles and you're down to less than 60%!
It's quite difficult to fit all that foam and not run out of decent storage place. That foam would obviously need to be low down and well spread out to provide a stable upright floating platform = this means taking up very valuable storage spaces. No point in the thing floating on it's side or upside down!
Very open debate on this topic with lots of varied ideas / opinions.
So foam enclosed in poorly constructed enclosures provides for rotting water storage!
Water tight is only water tight if there are no leacks, cracks or holes.... So keep the hull free from cracks or holes and it will float forever all by itself!
Foam coring and spray foam compartments seem to get saturated over time with water so much you can feel the weight and on small boats you actually can slosh around and hear the water in the foam. I cut a hole I lowest point without penetrate hull about 1" and using reducer that comes with wet vac run the vac sometimes for days to pull a vacuum on moisture and seems to pull out. Heat and fans seem to help too. I used a hvac vacuum pump once glued a valve into a foam rudder and run for week to lighten the rudder without skinning it to clear the water
I've never been a fan of user-installed foam, for a long list of reasons. I'm told Catalina offered factory foam (which yours might be) but there have been many threads here about it getting waterlogged, and how to remove it.
This was what I removed from Daydream when we first brought her home. The pieces were tightly packed into various compartments, with the covers screwed down:
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One somewhat minor quibble: The boat materials themselves also displace water, so you don't need quite that much foam. As best I can tell, fiberglass density is usually around 1.6 g/cc, so for 1000kg of boat, you need an extra ~375 liters of flotation (1000 * (1-1/1.6)).
Regardless, I agree with the consensus that it's hard to make a case for foam in a C-22. If I filled up all that space with foam, where would I put all my stuff?
In my post above I generalised in terms of floatation to boat weight ratio because I wanted my boat to be unsinkable, stay high and dry! Not just barely float.
My naval architecture studies done many years ago are a bit rusty but I dug out the reference materials. Of course when you are trying to calculate the reserve bouyancy left over in a tanker after a collision then things do get a bit more technical!
YMMV...
750kg of hull/deck/lining/fittings
450kg of solid cast iron keel
50kg of mast/boom/rigging/sails
Excluding all the paraphernalia that we "need" on the boat and the persons onboard!!!!!!!! (200 to 350kg's)
The boat being a hollow thin walled vessel the actual volume of the structural material is taken into account by using a bouyancy form factor = 0.375
The density of the foam added is additional weight reducing the floatation.
Because we want the thing to stay floating high and dry (if a sinking boat can be referred to as that!) we allow for 'additional' floatation multiplier = 1.2
So the mass of the fiberglass structure to be floated turns into = 0.375*750kg = 281kg
The mass of the keel to be floated can be reduced by like 2 or 3 kg's but really... = 450kg
The mass of everything out of the water stays the same = 50kg
So the total mass to be floated would be = 781kg ... excluding the persons onboard!
Sea water has a density in the region of 1.025kg/Ltr so you should float higher in sea water. Lets use fresh water density = 1.000kg/Ltr
Every cube of water displaced by floatation will be reduced by the weight of the floatation = average 35kg (sometimes more)/m³ of foam.
Thus we arrive at = 781/(1000-35) = 0.81 m³ of foam floatation.
This will just keep things afloat and awash! Hence the safety factor of 1.2 = 0.81*1.2 = 0.972 m³ of floatation foam of 35kg/m³ density.
So the boat will float but some of the occupants must swim... sooooo
= (781+300)/965 = 1.12 m³ foam include the safety factor = 1.12*1.2 = 1.34 m³ of floatation foam of density 35kg/m³ and now everybody can stay dry, floating on the half sinking boat trying to sail to some point of safety.
My naval architecture studies done many years ago are a bit rusty but I dug out the reference materials. Of course when you are trying to calculate the reserve bouyancy left over in a tanker after a collision then things do get a bit more technical!
YMMV...
750kg of hull/deck/lining/fittings
450kg of solid cast iron keel
50kg of mast/boom/rigging/sails
Excluding all the paraphernalia that we "need" on the boat
and the persons onboard!!!!!!!! (200 to 350kg's) The boat being a hollow thin walled vessel the actual volume of the structural material is taken into account by using a bouyancy form factor = 0.375
The density of the foam added is additional weight reducing the floatation.
Because we want the thing to stay floating high and dry (if a sinking boat can be referred to as that!) we allow for 'additional' floatation multiplier = 1.2
So the mass of the fiberglass structure to be floated turns into = 0.375*750kg = 281kg
The mass of the keel to be floated can be reduced by like 2 or 3 kg's but really... = 450kg
The mass of everything out of the water stays the same = 50kg
So the total mass to be floated would be = 781kg ... excluding the persons onboard!
Sea water has a density in the region of 1.025kg/Ltr so you should float higher in sea water. Lets use fresh water density = 1.000kg/Ltr
Every cube of water displaced by floatation will be reduced by the weight of the floatation = average 35kg (sometimes more)/m³ of foam.
Thus we arrive at = 781/(1000-35) = 0.81 m³ of foam floatation.
This will just keep things afloat and awash! Hence the safety factor of 1.2 = 0.81*1.2 = 0.972 m³ of floatation foam of 35kg/m³ density.
So the boat will float but some of the occupants must swim... sooooo
= (781+300)/965 = 1.12 m³ foam include the safety factor = 1.12*1.2 = 1.34 m³ of floatation foam of density 35kg/m³ and now everybody can stay dry, floating on the half sinking boat trying to sail to some point of safety.
And that looks a lot like the 1.34m³ from my calculation
Of course, the real test would have been to fill the boat with water and see if it worked before removing it !!!
Oh... nice "bakkie" (pronounced "buck-key") as we say in South Africa = nice truck!
My interest would be around keeping the boat afloat after a huge wave swamped it. The only requirement would be that the lowest part of the gunnells stay above water. That way bailing can make progress. Self-bailing cockpits make that more complicated. You would have to be able to close the cockpit scuppers or water just comes back through the scuppers as long as they are below the water level.
-Will (Dragonfly)
-Will (Dragonfly)
Personally I don't really get the need for "sink proofing" flotation
I generally assume the crew is in charge of keeping it afloat.
I seem to see this type of question asked for small boats. Maybe it is due to fear and inexperience ?
I haven't heard people asking how to make their 17th foot aluminium fishboat unsinkable and yet stats show they are more at risk.
it's not like you are going to run into a shipping container, 2 weeks from land, in a C22.
Discus !
I generally assume the crew is in charge of keeping it afloat.
I seem to see this type of question asked for small boats. Maybe it is due to fear and inexperience ?
I haven't heard people asking how to make their 17th foot aluminium fishboat unsinkable and yet stats show they are more at risk.
it's not like you are going to run into a shipping container, 2 weeks from land, in a C22.
Discus !
Thanks for the reply, I have now removed 99% of the foam and the boat is staring to stay dry.
Couldn't agree more-- never have understood the preoccupation with unsinkable. Catamaran,vanguard, laser-- all positive buoyancy but you aren't sitting in a 6' freeboard lazy boy chillin' with your margarita type of craft either.I haven't heard people asking how to make their 17th foot aluminium fishboat unsinkable and yet stats show they are more at risk.
Discus !
sage advice: don't sink it
My boat is only 19'. She has a cabin to sleep 4, enough space to camp for two over multiple nights, she is suppose to be MORC certified for self-righting. I would like to take her, at some point, offshore on overnight trips to places like Bimini or Dry Tortugas. Having a little positive buoyancy where there isn't enough room for a life raft, would be nice. I've been aboard a 56' sailboat that was buried briefly by a single wave. Small light boats bob over waves better than large heavy boats, but breaking waves will swamp them.
I know She's not designed for that kind of sailing, but she has some nice features that makes me believe, with a little prep and modification, it's not beyond her abilities. Positive buoyancy would be one of them. As a gunk holing weekender, there's no need.
-Will (Dragonfly)
Never seen an aluminum 17 ft production boat without built in flotation. Usually in the seats.Personally I don't really get the need for "sink proofing" flotation
I generally assume the crew is in charge of keeping it afloat.
I seem to see this type of question asked for small boats. Maybe it is due to fear and inexperience ?
I haven't heard people asking how to make their 17th foot aluminium fishboat unsinkable and yet stats show they are more at risk.
it's not like you are going to run into a shipping container, 2 weeks from land, in a C22.
Discus !
In 1977, the Coast Guard established flotation requirements for boats less than 20 feet in length,.
I bought an unsinkable sailboat. The flotation is in the upper portions, not in the bilge.
Been around small boats all my life. Strong swimmer. If it was only me on the boat, I wouldn't be too concerned about flotation, but I have an Admiral, 3 daughters, and two grandkids. Also, my friends are not all Olympic swimmers. It is really more about handling stress and staying cool. People that didn't grow up in water don't usually react well when the vessel they're in sinks out from under them. I'd rather have the partially floating boat to work with while waiting for rescue - particularly if others are with me.
My sailing waters aren't particularly hazardous, but there are partially submerged logs, pilings, pier sections, etc. that you encounter from time to time.
Part of the consideration is due to the fact that I can run 17 knots under power, giving me the opportunity to put a sizable hole in the boat.
I'm not advocating flotation for all. Just saying I'm glad I've got it and understand putting it in certain boats.
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Interesting. Wasn't aware of that. I wonder if the rules here are different. (I doubt it since the USA is a export major market)
I will say i have seen a few of the typical small production fishing boats end up at the bottom of lakes. Deteriorated flotation perhaps ?
I can see the advantage when it comes to confidence of crew if things go bad.
Flotation in the hull does have the benefit of improved visibility once sunk. Rafael Dinelli would probably have liked to have more when Pete Goss rescued him.
Swimming ability has little to do with it IMO. People shouldn't be on deck in a sailboat under way without a lifejacket on.
Flotation in the hull or not. People die all the time with small fishing boats, that evidently have mandatory flotation.
As I tell my guests, you can't swim when you are unconscious in the water.
My comment isn't a criticism. Simply an observation what make me wonder "why"
I find it interesting that the idea of adding floatation comes up a lot for small keelboats, which usually lack the space for the foam without losing a lot of storage, and yet you don't see many people with 30 foot keelboats asking about it.
While people have crossed oceans in sailboats that are 22ft long, maybe it is from the incorrect assumption of "my boat is small and therefore less safe than a larger one."
Like I say, I suspect it is driven by inexperience, because many small keelboats are owned by people new to sailing, who didn't learn in a dinghy.
Because of that demand, Catalina or it's dealers stuck what is now deteriorating, waterlogged foam, into places where it made no real sense. If people wanted that, Catalina should have put it between the liner and the hull. After all, the C22 was meant to be a beginner boat.
You said it better @Leeward Rail . Strong swimmers are not as apt to panic in a sinking because they are more confident in the water. Managing a sinking and rescue situation is much easier if you don't have to deal with mass panic. If you're on my boat, you'll have a pfd, so you won't have to be a swimmer to survive. My opinion anyway.
I don't know the details, but it's not unusual to find a small fishing boat with no occupant, followed by a search and recovery. Like you, I assume injury or heart attack/stroke type event.
Additionally, flotation does NOT death-proof a boat (again, my opinion). You still have injury, entrapment, and entanglement to deal with. Partially submerged means there may be cabin areas with water in them; i.e. potential drowning locations. Add a pfd that might prevent you from swimming out of a submerged compartment, and you could easily have a problem. All of these issues exist in a keel boat without flotation, so the only marginal improvement is; you MAY have a few more seconds to pull someone out since the boat won't be on the bottom.
Agree that adding flotation in bad places, where it holds water, etc. is worse than leaving it out. Very few of us will ever need our flotation (thankfully), but will be suffering continuously if it's done wrong and messing up the boat.
I think we are generally in agreement. I was just throwing out a pro-flotation perspective. It certainly won't save everyone...
I don't know the details, but it's not unusual to find a small fishing boat with no occupant, followed by a search and recovery. Like you, I assume injury or heart attack/stroke type event.
Additionally, flotation does NOT death-proof a boat (again, my opinion). You still have injury, entrapment, and entanglement to deal with. Partially submerged means there may be cabin areas with water in them; i.e. potential drowning locations. Add a pfd that might prevent you from swimming out of a submerged compartment, and you could easily have a problem. All of these issues exist in a keel boat without flotation, so the only marginal improvement is; you MAY have a few more seconds to pull someone out since the boat won't be on the bottom.
Agree that adding flotation in bad places, where it holds water, etc. is worse than leaving it out. Very few of us will ever need our flotation (thankfully), but will be suffering continuously if it's done wrong and messing up the boat.
I think we are generally in agreement. I was just throwing out a pro-flotation perspective. It certainly won't save everyone...
C22's (and keelboats in general) very rarely sink. When they do, they overwhelmingly sink at the dock. A few others while racing, with with way too much canvas up. Or because of gross negligence in basic maintenance. Last but not least, an unlatched lazarette hatch during a knockdown. Take these things off the list, there's precious little left to worry about.
So I have zero interest in flotation, personally. If I wanted to be safer, I would invest in better PFD's, a better VHF, and maybe an EPIRB or PLB ... someday.
But hey, whatever makes owning your boat the most enjoyable and carefree. I would never criticize anyone for adding flotation, or try to talk them out of it. Your boat, your choice!
So I have zero interest in flotation, personally. If I wanted to be safer, I would invest in better PFD's, a better VHF, and maybe an EPIRB or PLB ... someday.
But hey, whatever makes owning your boat the most enjoyable and carefree. I would never criticize anyone for adding flotation, or try to talk them out of it. Your boat, your choice!
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