Floatation... Discussion from Classifieds

A

Andrew

Well-known member
I do not understad what you are saying.
So if you have 3 flotation compartment in the boat you built than you have 3 places were you will have root from what you are saying. There is no way water can get to the compartment under the floor. I have replaced foam in a few boats that were made the wrong way in the past (2 weeks ago in a 2 year old G3 duck boat) and it is becuase they are not a sealed compartment.

See you are missing the point . If you you fill the boat with water to the top of the cockpit coaming the boat should floot at water level.( your boat) I have made this boat with enough foam to floot it with the plug out which will drain 4" of water out of the cockpit so I can still be able to run the motor.( same as the Estuary) The USCG has been to my shop and inspected the 16' I built 2 years ago done the same way and it surpasses all there requirements.

I would hope that Mr. Devlin has designed the boats with ample floatation. But I have increseced the pods in order to have more floatation so I guess just call me stupid if I build the boats with more floatation than what Sam and the Coast Guard reguire.

So in closing Andrew if you read the post you will see I talk about the HULL being built out of 3/8 plywood (not by me) and the bottom needs to be stronger. I have built 57 boats over the past 12 years and I try to make every one of them better and safer.

David,

I agree that if something is sealed, as in plastic box sealed... that would be ok.

All my reading points to the fact that wood breathes and epoxy breathes... and inevitably H2O invasion does occur over the years. The potential for rot/weight/smell...blah is high...

If a wave comes over and fills a duck boat, hopefully the boat can be bailed and the engine started in time before the next wave and the next. If not, i.e. the boat cannot be bailed in time for the next big wave... you'd want weight under your floor...not air... with people dogs and gear moving around in those conditions the chance for a turtle is greater with air.

If I had a true self bailing cockpit with super large exit points that would allow meaningful water escape... then that would be ok... like the larger fiberglass fishing boats... but we are talking dinky duck boats with small plugs that have to be manually removed... and as always... there are probably 30 decoys, gas tanks and batteries in the way of the plug... a real pain in an emergency.

I learned just the other day that my "Self-bailing pump" was disconnected by accident... that would have been a drag in an emergency.

BTW, I think your boats are world class and I'd buy one in a heartbeat if I ever decided to get a BBSB. This thread has nothing to do with David bashing...(I'm not from New Jersey ; ) it's a thread about "folks" who think that putting foam under the floor of a duck boat isn't right.

A
 
I think part of the agument is addressing the situation IF the boat is turned over. Reguardless of the likelyhood, the question is usually "what if it does happen?" There are schemes that place floatation offset, higher in the boat, etc. to facilitate turning the boat back over. Depending on water temperature, distance from shore, and water depth; any argument may be simply academic. The foam is certainly not going to be heavy enough to make the boat self-right. Having the foam higher in the boat is supposed to give more boat out of the water so you can remain afloat on top of a turtled boat and or facilitate the turning of the boat.

However, the argument of moisture accumulation and rot may be a different story. I think there is something that could be said for volume of the sealed area below the water line. There is definately a higher chance of moisture in the bottom of the boat - so the lower parts of the boat would be more likely to have moisture problems. Having all of the flotation in the top of the boat might have a better moisture advantage, but probably would not be a useful in dangerous situations. Having a fully self-bailing boat could be a significant feature that you may want as a trade-off for possible moisture infiltration. As with all boat characteristics - you should consider the trad-offs. Keeping the boat moving forward after being hit by a rogue wave could be huge advantage.

I'm not a professional - but I'd have the boat weighed each year and watch closely for weight gain. And keep it dry when not in use.
 
There are a bunch of things to consider.
Floatation only comes into play when it is submerged. If you have foam in the boat, ideally you would want it to keep you floating on the surface...thus "level floatation". You typically want the foam up under the gunnels and evenly distributed fore & aft.

Regardless of what the foam manufacturers say about urethane foam being "closed cell", it will still absorb water over time is allowed to stay wet. If it gets wet and absorbs water over time...get at the job, remove it and refoam. Some foams will absorb more than others which is why you want a marine certified foam.

As far as foam under the floor, I think I'd rather have foam down there instead of a place for water to collect. Unless ALL your foam is under the floor, the chances of a turtle is slight...unless it's an Outlaw Marine Boat. ;)


Lou
 
In all the replies I agree with DAVE,but nobody has mentioned that when the boat capsizes,fills up or whatever,rule of thumb? STAY WITH BOAT?? What about your flowtation?? I suggest a camo MUSTANG WORK SUIT!! YOU CAN ALWAYS REPLACE THE BOAT-BELIEVE ME! IN BOSTON HARBOR in 35 years I've witnessed 4 duck hunters,REPEAT just DUCK HUNTERS on different occasions BUY THE FARM!! For me close cell starts at home!!
 
To take this a slightly different direction... a good friend and forum member and I were just rehashing some of our more harrowing times in a boat the other day on the phone. I run a TDB 14 classic with the open top boat blind and he runs a BBSB with a fully enclosed sailboat style dodger. The common denominator for both of us when facing conditions we had no right to be out in... the canvas on the boats saved the day! We both experienced situations where we had waves breaking over top the boats, bows topedoing into waves and following seas washing over the stern. It was the canvas that kept the majority of the water out. Just some food for thought. Floatation is a must but I'd rather keep the water out whenever possible.

We also discussed crazy things like tying ourselves off to our bow lines to keep from getting tossed overboard. We both came up with that one independently in bad situations. Not things either of us want to experience again. But we're not gonna quit duck hunting so you never know!

Safe boating and being prepared is the best defense. A float coat is definately the safest way to go for your person.

Gene
 
I'm not a big fan of flotation at all. I've lived and earned my living on the ocean all my life. I knew a lot of people fisherman and hunters that have drowned or died of hypothermia on boats that gone belly up with flotation. For the last 21 years I've had the Windy a 40' Young Bros. that I fish in the most horrible weather. No flotation here. If a thru hull or an intake lets loose I better be able to solve the problem fast or she'll sink like a rock as will all of the boats I've had over the years. In my own opinion Boat flotation isn't going to save your life it is only going to give you a false sense of security. When I bought our Sea Ark for Sea Duckin a few years ago the first thing I did was remove the flotation from the bow and stern compartments because I needed the space for storage. Knowing your boats limitations, having your boat well maintained and equipped and being able to react in an emergancy is much more important than boat flotation.
 
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I don't really care what anyone does to their own boat but I just have one question. How is a boat upside down a worse situation then a boat 40 feet under? My nephew pulled 5 people from the water on sunday who were in a boat with no flotation. Since it completely sank out of sight I assume it had no flotation. Not sure how it would have been worse had it floated.
Not a criticism just wondering.

Tim
 
Flotation is only required in boats 20ft. and under. If the flotation is properly located the boat will remain up right when completely full of water. The foam should be located in the four corners of the boat as high as posible. The foam in the back and the front can't be any farther then one third of the distance from the bow or transom respectively. I had a new model tested last month and learned quite a bit. I'll post some pics if anyone is interested. Tom.
 
I have a factory built AA Broadbill. All the floatation is in the floor but it has never been an issue.
She is increadibly stable and I motored in half full of water once with no trouble. It's a glass boat
so rot isn't an issue. I will agree that good canvas is your greatest asset when things get ugly.
I will add that if David doesn't have a problem with foam in the floor I would not second guess
his experience or knowledge. John
 
Over 30 years ago I had the misfortune to be out sailing on Lake Huron when a storm came up very quickly and unexpectedly. I had two friends with me and we ran for the shelter of the nearest island. We didn't make it. A particularly large wave broke over the bow and drove the boat back down stern first. No canvas or pump was going to save the day. What had been a nice fall sail turned into a nightmare in a few minutes. The boat was swamped in a slit second.

The sailboat turtled and settled upside down. The three of us sat on the overturned hull and thought about our situation. The wind quickly pushed us into the lee of an island where we floated about a half mile downwind from the island and two miles off shore. We could feel the remains of the mast dragging in the sand bottom about 20 feet below us.

The air temperature was in the 50s and the water was about the same. I was wearing a tshirt, sweatshirt, rain jacket and life jacket. My friends were similarly dressed. We sat there for close to two hours until the Coast Guard came poking around checking out a report that a sailboat had gone down. The other two fellows kept trying to talk me into swimming for shore but I insisted on staying with the boat. I didn't feel up to the effort given the distance and conditions. I was glad we didn't try it. It was difficult to stay with the boat in the waves but it would have been more difficult to swim the distance to shore.

One of the fellows made a brief trip to the hospital where he was treated for mild hypothermia but we were otherwise OK.

I learned a few things that day.
  • When things go bad it is good to get lucky. We were lucky somebody saw our sails disappear and called it in.
  • Dress for the weather. You just never know how your day will turn out.
  • Wear your life jacket.
  • A floating boat is better than one that doesn't. Upright or upside down on top of the water is better than on the bottom.
  • The floatation in that boat was in the sides and in the bow. The boat was still upside down.
  • Be thankful for the Coast Guard. Those guys and gals will go out in any weather to save you.
  • Trust your training. I raced sailboats all my life and taught sailing. I might have misjudged the weather but otherwise made good choices.
I have been out in worse weather, fought bigger waves and had better luck since that day but I still remember it like it was yesterday.
 
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You have to have a set of large ones to try to sink your own boat to prove a point :) I can really respect that! It's a good bit of PR too :)

I wouldn't contemplate doing that with my yet to be completed Kara, even though I packed both ends with foam and under the floor too. I hope never to put myself in the position to have to find out!

I'm curious how people on this site would try it as well(?). Even if only to discover exaclty how much will it take to sink it. In my 9 to 5 daily work in the corporate world of pharmaceutical R&D we call it passing the red-faced test. The only red face in the pictures I could see was when you guys had to tilt the boat on it's side :) maybe the dogs had red faces, but I couldn't tell with all that fur :)

Anthony
 
I'm curious how people on this site would try it as well(?). Even if only to discover exaclty how much will it take to sink it. In my 9 to 5 daily work in the corporate world of pharmaceutical R&D we call it passing the red-faced test. The only red face in the pictures I could see was when you guys had to tilt the boat on it's side :) maybe the dogs had red faces, but I couldn't tell with all that fur :)

Anthony
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I don't need to do this since my boat design was already tested by the designer when he prototyped his design. I built the boat to spec so it will do the same as Dave's boat. Until I get the boat in 10-20 foot cresting waves, where it may get pushed over on its back, it will be fine just like this one.
 
A sink test is a pretty common practice for boat designers. I sank mine - well I put as much water in it as would stay in it. It is a learning experience.
 
This string has probably run most of its course...

Two things I learned from it.

1st: if a boat totally fills up with water in bad conditions... no matter how much bailing/pumping... you're probably stuck sitting there until help arrives. There is no freeboard left... keeping a weatherproof radio in the coat as opposed to the duck bag behind the 6 brant decoys isn't a good idea anymore.

2nd: David built a nice boat and I thought his demonstration was pretty cool...

Thanks, Andrew
 
I think the point was lost... but at least the point was made... and now people can make better informed choices...
 
Given the size of the flotation boxes in the back and one aprox. half that size in the front I would think that you would not need any foam in the bottom. If you do have foam in the bottom it needs to be a good bit less then what is in the boxes. The Coast Guard dorsn't like to see foam below the floor. The only foam under the floor in the 17.5ft. boat I had tested was in the four fiberglass stringers. It was about 25percent of the total foam. One thing that they said that would help bail the boat out quicker is to have a self bailer in the front of the motor well. The up ward force of the foam will cause the water to flow out the self bailer until the up and down forces equalize. Accept for the over night test the CG only lets the boat sit for 15min. after filling it with water and then record the resaults.
 
There are a large number of boats that have been and are being built using foam as a core to stiffen the structure either as a uniform sheet for panels or as Dave used, poured in to give the floor a very big boost in the rigidity department. A side benefit is the flotation. It can be a problem if the design does not include the high extra floatation compartments to keep the flooded vessel from attempting to self right like a decoy. But I would gladly take a floating/filled boat like Dave showed over a sunk one. In this size class that is a great demonstration of what you might encounter and how it will respond.
Many of the designs on Bateau.com use the filled floor idea to help with hull stiffness and it is common place in the glass boats in this size class.
Foam. like the other materials has had its issues with water, but is a viable choice if installed well. There are failures in the OEM industry but that can be said for any building choice.
One thing to remember. I know after a long home build or having a builder put a boat together the owner wants to have a long useful life from the vessel, but if used hard and put away wet most boats will show their age in a few hard seasons. But if maintained and stored well these wood hulls are still a good deal for the effort and dollars compared to more expensive/complicated building materials like aluminum or solid glass.

I will also say that having fished side by side with Jack, I know he would be one of the first guys I would want with me if it came down to trying to figure out a problem on a boat at sea. I am pretty sure that his 6 to 8 months or more a year on the open ocean rips of Montauk and beyond speak for themselves.
 
So... recent posters... what is your position on this... ???

Would you rather be in a duck boat with foam above or below the floor?

As Truman said to his Cabinet after his Economics Secretary was fired... "I am hiring a one-armed economist..." Why? his Cabinet asked.... "because the last guy would say -- on the other hand -- too much..."

Not to put anyone on the spot... but the folks this site has attracted over the last few years rarely take firm positions, rather, there is kind of a "soft, let's all be friends" approach... or, conversely, "let's make so and so look like an idiot..." this debate is about safety on the water, not who likes who today...

5-10 years ago, there would be a lot of both professional & amateur contentious debate but at least all the points would be vetted and builders and lurkers could overlay the facts they need onto their present situations...

Personally, I built a better boat 7 years ago because of the old style of vetting issues like these... I owe a great debt to the guys who stuck their necks out years ago on this forum because they weren't afraid of getting on someone's bad side... After years on the water (a lot of rough water)... the choices I made then are still paying off today.

So... what is your opinion? ... this is a safety debate about duck boats that could get into trouble on the water, not a political forum.
 
So... recent posters... what is your position on this... ???

Would you rather be in a duck boat with foam above or below the floor?

As Truman said to his Cabinet after his Economics Secretary was fired... "I am hiring a one-armed economist..." Why? his Cabinet asked.... "because the last guy would say -- on the other hand -- too much..."

Not to put anyone on the spot... but the folks this site has attracted over the last few years rarely take firm positions, rather, there is kind of a "soft, let's all be friends" approach... or, conversely, "let's make so and so look like an idiot..." this debate is about safety on the water, not who likes who today...

5-10 years ago, there would be a lot of both professional & amateur contentious debate but at least all the points would be vetted and builders and lurkers could overlay the facts they need onto their present situations...

Personally, I built a better boat 7 years ago because of the old style of vetting issues like these... I owe a great debt to the guys who stuck their necks out years ago on this forum because they weren't afraid of getting on someone's bad side... After years on the water (a lot of rough water)... the choices I made then are still paying off today.

So... what is your opinion? ... this is a safety debate about duck boats that could get into trouble on the water, not a political forum.
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Oh, I have learned that I'll get a bunch of whiney posts I stick my neck out and take a stand (usually you are #1 whiner in that regard, bud). I better not rock the boat, since this is the nicey-nice forum not the refuge don'tyaknow we don't talk directly, use grown up words or take stands.

Best to ya,

T
 
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