Most of my through hulls on my '81 h33 are under the settees. Galley sink. Knot meter. Depth sounder. Why did they not design the tops of the settees above the water line. Is this the same with other boats? If this were the case then any leak would be contained to the compartment. I spent a few minutes this weekend looking at this and realized that if the tops were just two or three inches taller and the compartment sides were sealed then any leek would be contained and the boat would not sink. Am I missing something? (I have been told only dumb questions are the ones not asked.)
dumb design question about through hulls
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a waterline is not a static point
Fill those settees up with water, and guess where the new waterline is going to be.
Fill those settees up with water, and guess where the new waterline is going to be.
To the pump
Most production boats are not designed with compartmentalization in mind. Instead the goal is to get any water that enters to flow to the bilge pump. Why? To hold down the cost. The boats I've seen with true compartmentalization are much more expensive and usually custom or limited production. Also, Hunter boats are known for their very open and airy spaces. Bulkheads with sealed doors detract from that feel. The number of Hunter boats sold attests to the consumer's desire for looks over more pragmatic and seaworthy boats.
Most production boats are not designed with compartmentalization in mind. Instead the goal is to get any water that enters to flow to the bilge pump. Why? To hold down the cost. The boats I've seen with true compartmentalization are much more expensive and usually custom or limited production. Also, Hunter boats are known for their very open and airy spaces. Bulkheads with sealed doors detract from that feel. The number of Hunter boats sold attests to the consumer's desire for looks over more pragmatic and seaworthy boats.
Good point
You bring up a good point there. I often thought that it would make sense to run all thru-hulls into one 12"x12" compartment with walls that ran up above the waterline for that same purpose.
You bring up a good point there. I often thought that it would make sense to run all thru-hulls into one 12"x12" compartment with walls that ran up above the waterline for that same purpose.
Rob
That’s called a sea-chest and its found on some boats. It is a secure way to admit water into the boat but you still need some outside of the sea-chest to handle things like the head and sink discharge because you don’t want to mix them with water intakes for cooling etc. All the best, Robert Gainer
That’s called a sea-chest and its found on some boats. It is a secure way to admit water into the boat but you still need some outside of the sea-chest to handle things like the head and sink discharge because you don’t want to mix them with water intakes for cooling etc. All the best, Robert Gainer
John
John said, a waterline is not a static point Fill those settees up with water, and guess where the new waterline is going to be. So what? The waterline will go up but how is that a problem? All the best, Robert Gainer
John said, a waterline is not a static point Fill those settees up with water, and guess where the new waterline is going to be. So what? The waterline will go up but how is that a problem? All the best, Robert Gainer
is that a serious question?
yes, I've seen a sea chest on a research vessel, a very large ship-like research vessel, but I'd hate ever to see one an a small sailboat. When a sailboat heels the waterline on the leeward side goes so high that your settees would have to be almost a meter above the sole to have any hope of working. Doubtful that the idea's going to sell, especially on boats such as mine that have such items as refrigerator compressors, subwoofer speakers and water heaters installed in the settees. Easier just to beef up the seacocks, double up the hose clamps, and install a redundant bilge pump.
yes, I've seen a sea chest on a research vessel, a very large ship-like research vessel, but I'd hate ever to see one an a small sailboat. When a sailboat heels the waterline on the leeward side goes so high that your settees would have to be almost a meter above the sole to have any hope of working. Doubtful that the idea's going to sell, especially on boats such as mine that have such items as refrigerator compressors, subwoofer speakers and water heaters installed in the settees. Easier just to beef up the seacocks, double up the hose clamps, and install a redundant bilge pump.
sea chest
Caliber is one mfg which uses them on all their boats as an added safety feature. As I recall, it's pretty low on the WL
Caliber is one mfg which uses them on all their boats as an added safety feature. As I recall, it's pretty low on the WL
another question
Thanks John Farnsworth for your reply. Makes sense. My thought was more how scared I am of coming to the boat and finding it sunk or partially submerged. I live 250 miles away and the longer the time I am away, the more anxiety I have about there being something wrong on the boat. This past weekend we had our bilge pump switch go out. It was kind of a wake up call. I thought about it and got to looking at all through hulls and wondering if I could improve somehow on safety. I guess my next question is ... Do people worry more about leaks happening while they are on the boat or when they are gone away? I usually get to my boat every couple of weeks but sometimes (like this time -- extreme circumstances) it can be four or five weeks.
Thanks John Farnsworth for your reply. Makes sense. My thought was more how scared I am of coming to the boat and finding it sunk or partially submerged. I live 250 miles away and the longer the time I am away, the more anxiety I have about there being something wrong on the boat. This past weekend we had our bilge pump switch go out. It was kind of a wake up call. I thought about it and got to looking at all through hulls and wondering if I could improve somehow on safety. I guess my next question is ... Do people worry more about leaks happening while they are on the boat or when they are gone away? I usually get to my boat every couple of weeks but sometimes (like this time -- extreme circumstances) it can be four or five weeks.
Aren't the Seachests Sealed closed
with a cover above the waterline. That way you don't worry if your boat heals. Like mentioned before the Caliber Yacht 47 LRC (Long Range Cruiser) has a Sea Chest. http://www.caliberyacht.com/Downloads/Caliber_47LRC_SEries_Brochure.pdf It does alleviate the need to dozens of Thru Hulls and allows only a few to keep an eye on.
with a cover above the waterline. That way you don't worry if your boat heals. Like mentioned before the Caliber Yacht 47 LRC (Long Range Cruiser) has a Sea Chest. http://www.caliberyacht.com/Downloads/Caliber_47LRC_SEries_Brochure.pdf It does alleviate the need to dozens of Thru Hulls and allows only a few to keep an eye on.
When I rebuilt Bietzpadlin I was concerned about
thru hull failures so I made my galley sink drain and the sink in the head drain into pipes that extend above the water line when the boat is on an even keel. It is a simple enough thing to do. With a hole saw cut a hole through the hull where you want the drain and at the angle you need. each drain is comprized of a 1 1/2 inch pvc schedule 40 pipe and a ball valve. The valve is solvent welded to the pipe and the pipe is bonded into the hull with polyester resin and fiberglass both inside and outside. The pipes are reinforced for their full length with fiberglass and resin. My raw water for the head and for the engine cooling are conventional seacocks. My bilge pumps discharge into the cockpit scuppers.
thru hull failures so I made my galley sink drain and the sink in the head drain into pipes that extend above the water line when the boat is on an even keel. It is a simple enough thing to do. With a hole saw cut a hole through the hull where you want the drain and at the angle you need. each drain is comprized of a 1 1/2 inch pvc schedule 40 pipe and a ball valve. The valve is solvent welded to the pipe and the pipe is bonded into the hull with polyester resin and fiberglass both inside and outside. The pipes are reinforced for their full length with fiberglass and resin. My raw water for the head and for the engine cooling are conventional seacocks. My bilge pumps discharge into the cockpit scuppers.
Chuck the best way I have found to cut down
on anxiety while I'm away from the boat is the thought that I have done my best to protect it and that the insurance premium is payed up. It is also a good idea to ask a neighbor, a liveaboard or someone who is usually there to check your boat every once in a while and give him your phone number.
on anxiety while I'm away from the boat is the thought that I have done my best to protect it and that the insurance premium is payed up. It is also a good idea to ask a neighbor, a liveaboard or someone who is usually there to check your boat every once in a while and give him your phone number.
Best way to sleep at Night
I have found (and read here) that the best insurance against sinking is to keep the thru hulls CLOSED when not on board. I religiously close them before leaving... part of my check list. If your thru hull or hose leaks, the bilge pump will probably not be able to keep up with it anyway. Make sure your thru hull are well installed and lubed and sleep better at night.
I have found (and read here) that the best insurance against sinking is to keep the thru hulls CLOSED when not on board. I religiously close them before leaving... part of my check list. If your thru hull or hose leaks, the bilge pump will probably not be able to keep up with it anyway. Make sure your thru hull are well installed and lubed and sleep better at night.
First water is always the worst
Our first large boat was a Clipper Marine 26. When we went to launch it the first time, I forgot to replace the boat speed sensor. (We had removed it so it would not burn up trailering the boat down the highway) We backed the trailer down the ramp, launched the boat, christened it with Miller High Life (we're in Milwaukee) and then stepped on board to start it up. There was about a foot of water in the area under the dinnette. That area is trapped between the bulkhead, keel trunk and battery compartment. The water rose to the level of the water outside the boat and stopped. When I stepped on board, I inserted the sensor and pumped the water out with a hand pump. The CM26 has a small bilge area but it is not connected to the area under the dinnette. This was a good experience on two counts. (1) We never, ever forgot to reinsert a sensor after trailering. (2) We never worried about a little water in the boat. (Kind of like the first ding on a new car) We always close every thru-hull every time we leave the boat overnight and have the instrument sensors safety-wired. (Our current boat is a Hunter 31)
Our first large boat was a Clipper Marine 26. When we went to launch it the first time, I forgot to replace the boat speed sensor. (We had removed it so it would not burn up trailering the boat down the highway) We backed the trailer down the ramp, launched the boat, christened it with Miller High Life (we're in Milwaukee) and then stepped on board to start it up. There was about a foot of water in the area under the dinnette. That area is trapped between the bulkhead, keel trunk and battery compartment. The water rose to the level of the water outside the boat and stopped. When I stepped on board, I inserted the sensor and pumped the water out with a hand pump. The CM26 has a small bilge area but it is not connected to the area under the dinnette. This was a good experience on two counts. (1) We never, ever forgot to reinsert a sensor after trailering. (2) We never worried about a little water in the boat. (Kind of like the first ding on a new car) We always close every thru-hull every time we leave the boat overnight and have the instrument sensors safety-wired. (Our current boat is a Hunter 31)
cool boat
I spent an hour with the designer of the Caliber LCR 47 when I began shopping for a boat in the 45'+ range. It has a zillion cool features, such as integral tanks for 275 gallons of water AND 275 gallons of fuel. Unfortunately, the base price of the boat was just under half a million, which meant by the time you added electronics and paid taxes you could easily be up to $600k. Ouch. When you can pay half as much for a BeneHunteLina, poly tanks and conventional thru-hulls start looking pretty damned attractive. The silver lining is that I've discovered that for the most part I can scrape by with 100 gallons of diesel and 200 gallons of water, especially since I'm not above strapping those yellow jerry jugs to the rail for longer trips.
I spent an hour with the designer of the Caliber LCR 47 when I began shopping for a boat in the 45'+ range. It has a zillion cool features, such as integral tanks for 275 gallons of water AND 275 gallons of fuel. Unfortunately, the base price of the boat was just under half a million, which meant by the time you added electronics and paid taxes you could easily be up to $600k. Ouch. When you can pay half as much for a BeneHunteLina, poly tanks and conventional thru-hulls start looking pretty damned attractive. The silver lining is that I've discovered that for the most part I can scrape by with 100 gallons of diesel and 200 gallons of water, especially since I'm not above strapping those yellow jerry jugs to the rail for longer trips.
Didn't the titanic have something similar....
...with compartments that was suppose to isolate any water leaks? abe
...with compartments that was suppose to isolate any water leaks? abe
don't know about the Titanic, but...
...most modern ships use sea chests as the intake for their water ballast system. Unfortunately, the sea chest tends to play havoc with the environment because it can house invasive species even when measures are taken to exclude such species from the ballast.
...most modern ships use sea chests as the intake for their water ballast system. Unfortunately, the sea chest tends to play havoc with the environment because it can house invasive species even when measures are taken to exclude such species from the ballast.
Dont know about that...
was on a old Pearson Wanderer with my Capt'n friend that chartered the vessle for a week, just bobb'in around with no wind. All of a sudden the wind pipes up and we start to heel over just a bit. Smiles immediately come to our faces... until one of the crew says "Why is water coming out of the sink"? Capt'n says "go down below and figure out whats going on". To my dismay... I looked under the sink and there was no way to close close the thru hull. Just a straight shot to the sink! Not double clamped... no wooden bung hanging around. Now the sink was about 2 feet above the waterline... however water was pouring in. I think another 2' would have maybe stopped the water flow... however I think it might of looked pretty silly!
was on a old Pearson Wanderer with my Capt'n friend that chartered the vessle for a week, just bobb'in around with no wind. All of a sudden the wind pipes up and we start to heel over just a bit. Smiles immediately come to our faces... until one of the crew says "Why is water coming out of the sink"? Capt'n says "go down below and figure out whats going on". To my dismay... I looked under the sink and there was no way to close close the thru hull. Just a straight shot to the sink! Not double clamped... no wooden bung hanging around. Now the sink was about 2 feet above the waterline... however water was pouring in. I think another 2' would have maybe stopped the water flow... however I think it might of looked pretty silly!
The problem with Titanic was two fold.
Number one, the watertight bulkheads didn't go all the way up and weren't capped off so the water just flowed over them. Number two, the glancing blow compromised too many for them to keep her afloat even if they were sealed off.
Number one, the watertight bulkheads didn't go all the way up and weren't capped off so the water just flowed over them. Number two, the glancing blow compromised too many for them to keep her afloat even if they were sealed off.
Yeah, but
If they only would have been looking at their radar. Oh no, I meant looking with their binoculars. The lost pair. And if they only had strong rivets in the hull instead of iron-age stuff that popped too easily. Let's see, what else? Oh! A Captain that wasn't an egotistical maniac that didn't want to keep the ship at high speed in a "mine field". OK, a Captain that knew what he was doing. He did good to go down with the ship. Bet he would have been hung if he didn't. This tragedy is a text book case in the study of 'The Final Factor' of accidents. Take any one of them away and the boat is safe.
If they only would have been looking at their radar. Oh no, I meant looking with their binoculars. The lost pair. And if they only had strong rivets in the hull instead of iron-age stuff that popped too easily. Let's see, what else? Oh! A Captain that wasn't an egotistical maniac that didn't want to keep the ship at high speed in a "mine field". OK, a Captain that knew what he was doing. He did good to go down with the ship. Bet he would have been hung if he didn't. This tragedy is a text book case in the study of 'The Final Factor' of accidents. Take any one of them away and the boat is safe.
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