filled with water!!!!

B

budelik

New Member
My very old laser (from 1970's) got left out last winter without a cover. The cockpit drain got blocked with leaves and the cockpit completely filled with water. The bow was also down. I scooped the water out and as I tried to turn the boat to completely drain out the water I noticed that it was very heavy and there were sloshing sounds coming from inside!!! Lifting the bow, A LOT of water came out the stern drain hole. A couple of years before, I had rebuilt the mast step (from within) after installing an inspection port. The port was closed tight. The mast step did not leak. How did the water get into the hull? What should I do?
Also, when I opened the hull before to repair the mast step,I found the old plastic flotation cubes were completely degraded. I could not find new ones in Italy where I am, so, noticing that new ones were made from PET plastic, I collected A LOT of PET1 1/2 liter plastic drinking water bottles and completely filled the hull with them! Does anyone know how much cubic volume of air one needs to keep the boat from sinking? Thanks.
 
There is a little 'breathing' hole underneath the bow end of the toe-strap. Since the bow was down - I assume it filled up the hull by using this hole.
 
Gfinch said:
There is a little 'breathing' hole underneath the bow end of the toe-strap. Since the bow was down - I assume it filled up the hull by using this hole.
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Thanks. Sounds possible. I guess one way to find out is to go out sailing! That's why I asked about buoyancy volume!!!!
 
as to how the water got in there:
put some water in, and see if you can find where it leaks out- tip the hull in various directions to test those areas. Don't put a LOT of water in the hull, because water is heavy, the hull isn't engineered to bear the weight of a lot of water inside it, and you risk damaging it.

as to bouyancy volume, how many bottles:
Things float when they displace as much weight of water, as what the thing weighs. So:
- The hull weighs 57kg new. Add say 8kg for spars, etc - say 65kg total. If it's absorbed more water and weighs more, you can ignore that since that water has "neutral bouyancy" - the absorbed water won't sink the boat in water. (It WILL make it FLOAT LOW, but it will NOT SINK it.)
- It's hard to determine what volume of water the boat hull alone (not the air inside it) displaces.
- To simplify things, for this little calculation, let's use the conservative assumption that the hull itself displaces zero water. This is wrong, but it's easy to work with, conservative (that is, it's wrong in a direction that helps you, not hurts you), and not "very" wrong in the bigger picture.
- A 1-liter bottle displaces 1 liter of water volume, which weighs 1kg.
- So using 1.5 liter bottles: 44 bottles x 1.5 liters = 66 liters of volume, which displaces 66kg of water, and will float a 66kg mass... or more precisely, 44 1.5-liter bottles give a 66kg mass "neutral bouyancy" -- that is, it would neither sink, nor float positively towards the surface.

How many bottles do you have inside the hull? Is there at least 44 in there?
More than 44 will give "positive bouyancy," which means if you push it under, it will actively return to the surface.
10 more bottles = 15 liters = 15kg of "bouyancy force" which seems like a reasonable margin.

More won't hurt a thing... if you can fit 70 bottles ( ... if you care to COLLECT 70 bottles! ... ) ... do it!

hope it works out,
 
fill the hull with low pressure (you don't want the hull blowing up like a balloon), then apply some dishwashing soap mixed with water, you'll see bubbles where its leaking

the most common leak spots in any laser are:

-inspection ports
-Gunwales
-traveler fairleads
-bailor
-drain plug assembly
-hiking strap
-daggerboard trunk
-bow eye fitting
-mast step
 
No need to make any major checks. If the cockpit was full of water, it leaked into the hull through the breathing hole.
 
budelik said:
How did the water get into the hull? What should I do?
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The gap between the deck and the bottom is sealed with a brass fitting, so check that the seal is still good. If you are certain that the mast step was not the culprit, then it could be leaking through the cockpit drain into the hull cavity if the seal there is bad. However, if the boat was tipped forward and the cockpit is full, yes, I agree with the other posters it likely leaked through the breather hole under the hiking strap.
 
oztayls said:
The gap between the deck and the bottom is sealed with a brass fitting, so check that the seal is still good. If you are certain that the mast step was not the culprit, then it could be leaking through the cockpit drain into the hull cavity if the seal there is bad. However, if the boat was tipped forward and the cockpit is full, yes, I agree with the other posters it likely leaked through the breather hole under the hiking strap.
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Where is this brass fitting?
 
RobertM said:
Where is this brass fitting?
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The cockpit drain fitting:
pimage_118_000000001.jpg
 
I cannot believe that large quantities of water leaked in through the breather hole since air has to come out at the same time.
Older boats had a black? plastic tube into which the bung fitted, which can break. I think it is likely that it has and water has leaked from the cockpit into the hull via the plastic flange. Replace it with the brass version shown above.
 
Dude, it's the breather hole. If the cockpit fills with water and the nose of the boat is angled down, the hull WILL fill up. It has happened to me from a single overnight rainstorm.
 
there was either some foam or air bags inside originally, it helps keep the laser afloat even when completely filled with water, its very hard to sink a laser
 
Greg Morrissey said:
Would baloons be the same as water bottles...
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Apologies if this next bit is dull but for the avoidance of any possible confusion due to language differences - I'm not exactly sure what you're referring to when you ask about "balloons" and it might be different in Ireland. I'm in the USA - here, "balloon" normally refers to a very thin and fragile rubber bladder that you blow up and tie off for kids parties, etc. These balloons pop very easily.

So if this is the kind of balloon you're thinking of ---
- in regard to FLOTATION, yes, but ...
- in regard to PUNCTURE RESISTANCE, no.
Whatever you put inside the hull for flotation, must keep it's flotation property while getting bounced around in there. USA-type balloons would get punctured by the many sharp pointy places, which include fibreglass fibres, the pointy ends of screws + so on, splinters on the edges of wood pieces, etc.

Anything will work as flotation inside the hull as long as what you put in there:
a. floats, and the higher it floats the better; and
b. stays afloat- that is, it will not sink if punctured or otherwise damaged while getting bounced around inside the hull.
Lighter weight is obviously better than heavier. Any kind of closed cell foam works. Sturdy bottles work.
 
I was thinking more of the rubber balloons that you would find inside a ball as they are much harder to pop and are easily availible to me.
 
Greg Morrissey said:
I was thinking more of the rubber balloons that you would find inside a ball as they are much harder to pop and are easily availible to me.
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I'm not familiar with those so I can't offer an opinion. The key consideration is whether they would remain inflated bouncing around inside the hull. From your description, I wonder how sturdy they are when they don't have the ball outside them, protecting them. Kinda like the tube inside a bicycle tire or something?

Also think about what happens when the boat DOES take on water- the balloons will be pressed pretty hard against the inside of the hull by the water. This is exactly the time when you need the flotation to work. Think about how likely it is that these balloons will survive the water pressure, being pressed, scraped+ rubbed against the inside of the boat.

Whatever it is, you just need something that's not going to fail to float (displace water) when the boat fills up.
 
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