flotation tanks

[K.C. Walker]

Jamestown distributors sells a two-part expanding urethane foam designed as flotation foam http://www.jamestowndistributors.com/us ... ation+Foam . Any thoughts on that for inside the flotation tanks? I suppose that it might make it more difficult for future repairs. However it would add a bit of rigidity to the seat tops and the hull.

My boat has flotation foam under the side decks. I suspect that they are original. There is some rigid plastic sheeting that is right behind the combing and down to the seat and there are numerous sheets of 1 inch flotation foam behind that. The volume of flotation I would think equals half that of the seat tanks. It seems like a pretty easy place to add flotation.

KC

[Baysailer]

This is an interesting read and I'm going to toss out a counter thought but I could be all wet (pun intended). Years ago I read a book by snipe sailer Ted Wells "Scientific Sailboat Racing" (still one of my favorites). In the book he said you don't want the floatation to low in the boat or the boat to float to high on its side. Having it to low in the boat will make it unstable after righted and to high on its side will make it want to turtle. Doing a search of old posts I see there are others who question the floatation locations on a DS.

So if having the seat cavities full isn't the answer what is? Possibly fewer noodles in the seats say about half full probably the same for the bow cavity. This should provide enough floatation and allow the DS to sit a bit lower in the water. If more was needed possibly using poured 2 part urethane under the deck areas.

On a similar note I saw this mast float in APS that could be used on windy days. Could also put a noodle in or on the mast.

http://www.apsltd.com/p-2072-mast-float ... nsail.aspx

Fred DS1351

[GreenLake]

There's a type of boat for which these effects reach a natural extreme: the catamaran. Just last week I came across a description of a self-righting catamaran. It uses a mast float. When it tips, it tips a little more than 90 degrees, because when it floats on one ama the mast foot is quite a bit above the water.

Apparently you then make one of the shrouds tighter (the lower one) and loosen the other, until the hull is first vertical, then tips even further back and rights the boat. After the hull is level, you make the shrouds symmetric again to straighten the mast. There was a nice video, too, but I can't find the link.

For the DS, how high should it float? Should the centerboard be above the water when you start to right it? Not rhetorical questions, I don't have the answers. All I'm sure of, is that with the tanks filled with air / flotation I'd predict (based on this discussion) my boat to float fairly low, low enough for all three tanks to be submerged (full or in part). It that prediction is correct, then righting the boat would appear rather difficult.

Fred, if you fill the tanks partially with floatation they would normally still provide full buoyancy (initially) as they are supposed to be airtight. The floation is just a backup in case water gets in.

[persephone]

Out of curiosity I re-sealed my seat tanks and installed an air valve on the inspection cover. After several attempts to get the tank to hold pressurized air I gave up.
The air goes out almost as quickly as I put it in. Many of the holes appear to be in the bonding of the seat to the side under the deck edge (DS 1).
If it isn't air tight, it isn't water tight!
Guess I'll have to budget plenty of money to install foam, tubes or bottles. I have no delusions that those tanks won't fill with water eventually.

[algonquin]

Out of curiosity I re-sealed my seat tanks and installed an air valve on the inspection cover. After several attempts to get the tank to hold pressurized air I gave up.
The air goes out almost as quickly as I put it in. Many of the holes appear to be in the bonding of the seat to the side under the deck edge (DS 1).
If it isn't air tight, it isn't water tight!
Guess I'll have to budget plenty of money to install foam, tubes or bottles. I have no delusions that those tanks won't fill with water eventually.

My DS, a 1963, has the same issue. The tanks leak some. I have a drain plug on each seat tank and one in the bow tank that I pull once a season and a significant amount of water comes out. I have heard that some is due to condensation forming in the tank and some from water making its way in after a heavy rain. In either case, if the boat went over without additional flotation in the tank I would guess that there would be a window of time in which I could upright my DS before that air in the tanks was displaced by water.

I have come close to a knock down in my DS. It is a little unnerving but I could deal with it when it happens. I have previously suffered a knock down in my 23 foot Venture of Newport. That was no fun at all. It gradually self righted. The only flotation was air in the lockers and fortunately the cabin only partially filled with water. Did I mention that my Coors Light spilled ? Brad

[kokko]

I did remove the old sodden foam and replaced it with the pool noodles. It took about 50 .

[Phill]

My favorite kakak "extra" bow and stern floation is 'wine in box bladders'
5 litters. Need many, emptied many, fell over, did a dry land roll recovery.

Seriously,
First, please search this forum and read previous posts about saftey and DS Floatation.

To answer Greenlakes comment, the Day Sailer will MOST LIKELY go all the way to turtle. Too many capsizes by even the best racers end up totally upside down. It will take two to get 'er up, IF you have proper flotataion.

Even if the floatation is in the wrong place for easier recovery, Please refill your seat and bow tanks with positive, non air filled(bottles or bladders) and enjoy your carefree sailing adventures. I have rescued too many DS's with leaky tanks and the foam is really barely enough to keep the boat off of the bottom if the tanks partially fill with water.
Any kind of air filled device will be hard to inspect after stuffing into the far reaches of the tanks, and can not be trusted. Additionally, if you tow to any altitude, the reduced pressure will certially pop those bladders or bottles. Hmmmmm, I'll bet that if you park in the hot sun, the heat expansion inside those tanks, (like the inside of your car) could also seriously stress the lid of those bottles. (my seats are dark blue )

If you want floatatoin placed higher in the hull, I've seen the pool noodles fastened under the rail behind the coamings, and shaped and fastened to the underside of the cuddy deck. I have fully stuffed the area above the bow tank, behind the hatches and bulkhead there with 1lb styrofoam. Easily shaped with saws and sandpaper, that area is totally full of foam, in addition to the seat and bow tanks with the same foam.

Please rig for worst case and you wont have to explain why you didnt.

Just my .02 worth