Re: [bolger] Re: Flotation Help
| My solution is to build the compartments with big limber holes at the low point and big vent holes up high (are they still limbers when up high?) and set in a foam block built up from slabs of the blue stuff that has "feet" (small, 3/4" square blocks of 1/2" thick foam glued to the "motherblock") attached to the bottom, top and sides in just enough places to wedge the main block in place yet keep the block clear of the walls by enough to allow air and water to pass all around and under with very little contact area between the painted plywood and the foam, just where the "feet" are, no contact between the plywood and the "motherblock". Air movement and drainage keep the compartments dry and I'm able to flush them out by sticking a hose in though the limbers on occasion. Yes, I've lost some volume of flotation, a trade-off I'll take to avoid what I found in the
past when I dug and scraped waterlogged foam out of a compartment only to discover rotted plywood underneath. I did this on a Diablo I built in 2001 and so far it works great. Well... the flotation hasn't been put to the ultimate test but the flotation compartments, hull and foam blocks were in good condition when I pulled them during a remodeling re-fit last winter. Rick --- OnSat, 1/30/10, Douglas Pollard<dougpol1@...>wrote: |
In a set of plans by the late Joe Dobler he suggest using 4mm plywood bonded to 2 inches of foam and covered in fiberglass set in epoxy to make the top of bow and stern enclosures. The idea is to make a light strong seat with built in flotation. The foam ends up high enough to give good stability if the boat swamps and the foam will not absorb water. The idea could be extended to seats or side decks. I will give it a try in my current project (a Dobler design).
Bob Hauser
Bob Hauser
I would think that the wood will rot long before the foam does in the
case of a leak. But it is still a good idea to keep the foam away from
the wood so that air can circulate between foam and wood. Wood is going
to rot sooner or later and nothing can be done about that. Poisons will
stop it for a while until they leach or wash out. Wooden boats are not
permanant. I suspect that foam takes up less space in the boat than
bottles and space is at a premium in small boats. A wooden boat with
water ballast doesn not need flotaion for it's self as it will float but
it does need flotation for a great deal of it's contents.
The really good thing about bottles is they can be put in a net and air
can circulate all around and through them. That is a huge advantage. Doug
Rick Bedard wrote:
case of a leak. But it is still a good idea to keep the foam away from
the wood so that air can circulate between foam and wood. Wood is going
to rot sooner or later and nothing can be done about that. Poisons will
stop it for a while until they leach or wash out. Wooden boats are not
permanant. I suspect that foam takes up less space in the boat than
bottles and space is at a premium in small boats. A wooden boat with
water ballast doesn not need flotaion for it's self as it will float but
it does need flotation for a great deal of it's contents.
The really good thing about bottles is they can be put in a net and air
can circulate all around and through them. That is a huge advantage. Doug
Rick Bedard wrote:
>
> Not to stir up trouble but this (quote below) is exactly the reason
> why I do not use this type of foam.
> In my world if there is a leak on a boat kept in the water, I may not
> know it until the foam is softened and waterlogged, allowing rot to
> get a good start on the wood in contact with that soggy foam.
>
> Rick
>
>
>
>
> Not to worry. Here's from their FAQ
>
> 14. *Is this foam water resistant?*
>
> Yes, but with the following caveat.
>
> ...it should never be submerged in contact with water permanently.
> Over a period of years the water contact can begin to soften the
> foam and cause it to lose its closed-cell status.
>
>
> On Jan 29, 2010, at 7:40 AM,GBroadlick@...
> </mc/compose?to=GBroadlick@...> wrote:
>>
>> This is what is coming
>>http://www.uscomposites.com/ foam.html
>> <http://www.uscomposites.com/foam.html>
>
>
>
>
>
Exactly!
From:Rick Bedard <sctree@...>
To:bolger@yahoogroups.com
Sent:Fri, January 29, 2010 9:23:54 PM
Subject:[bolger] Re: Flotation Help
| Not to stir up trouble but this (quote below) is exactly the reason why I do not use this type of foam. In my world if there is a leak on a boat kept in the water, I may not know it until the foam is softened and waterlogged, allowing rot to get a good start on the wood in contact with that soggy foam. Rick
|
14.Is this foam water resistant?
Yes, but with the following caveat.
...it should never be submerged in
contact with water permanently. Over a period of years the water contact can begin to soften the foam and cause it to lose its closed-cell status.
| Not to stir up trouble but this (quote below) is exactly the reason why I do not use this type of foam. In my world if there is a leak on a boat kept in the water, I may not know it until the foam is softened and waterlogged, allowing rot to get a good start on the wood in contact with that soggy foam. Rick
|
And as I mentioned in an earlier post, expanded polystyrene doesn't absorb water... doc --- OnFri, 1/29/10, Mark Albanese<marka97203@...>wrote:
|
Not to worry. Here's from their FAQ
14.Is this foam water resistant?
Yes, but with the following caveat. The foams that we sell are considered closed-cell, which means that each cell that makes up the foam structure is completely closed off from surrounding cells which prevents it from acting like a sponge. It is completely safe for this foam to be in contact with water for hours/days/weeks and even months with no adverse effects. However, it should never be submerged in contact with water permanently. Over a period of years the water contact can begin to soften the foam and cause it to lose its closed-cell status. This foam is designed primarily to be used as an insurance policy in case of damage/holes that could cause a vessel to lose buoyancy. Pinhole sized openings would essentially have no effect on the foam since the amount of exposure is so minimal but you should always make repairs as soon as possible to keep the foam effectiveness as good as possible. This will be the case with all after market closed-cell polyurethane foams and even manufacturer installed foams.
I hot glued the caps onto gallon milk jugs and filled the bow area below the standing platform of my Micro that way. I also have about 10 cu ft of closed cell foam under the deck.
MylesJ
This is what is coming
http://www.uscomposites.com/foam.html
http://www.uscomposites.com/foam.html
I could just as easy enclose the space without the foam. I have already notched the frames at the chine for water movement. The notches if left open would allow air to move from bow to stern but i do not know if it would be sufficient. It would also provide Titanic like flotation, hole the boat and fill all the chambers.
I
-----Original Message-----
From: Walter <walter@...>
To: bolger@yahoogroups.com
Sent: Fri, Jan 29, 2010 9:22 am
Subject: [bolger] Re: Flotation Help
From: Walter <walter@...>
To: bolger@yahoogroups.com
Sent: Fri, Jan 29, 2010 9:22 am
Subject: [bolger] Re: Flotation Help
--- Inbolger@yahoogroups. com, Mark Albanese <marka97203@ ...> wrote:
>
> On the other hand I think you'll find that all the two part pour in
> marine flotation foams are the closed cell type, similar to this.
>http://tinyurl. com/y96qsrx
>
>
> I've got some filling the ends of a ten year old, very neglected 16'
> sharpie. No rot. I filled the chambers before adding the deck so had
> to do a little trimming through its self generated crust, which
> seemed to require sealing. Light fiberglass is good, though the
> trimmed through cells looked like they'd use up an awful lot of
> epoxy. I used a coating of Snow Roof. The stuff does generate some
> mechanical force while expanding, but anything well built ought to
> hold up.
>
> I tested some once by holding it under water for a week with no
> addition in weight.
>
> It adds extra structural integrity.
>
> Air bags are also quite nice for the occasional spill.
>
> Mark
>
Yes. the two part marine flotation foams are closed cell- check this web page -
http://www.shopmani nc.com/foam. html
Coast Guard regulations on flotation for boats under 20' state that the boat should have positive, level flotation. This eliminates any kind of sealed air chambers, bags, ping pong balls, etc. or any flotation not permanently installed, if you are going to pay attention to CG regs.
I have been using two part foam in sealed chambers in many boats over many years, and have not had any problems reported to me. Seal the interior with epoxy before you pour the foam, make sure the space is totally full, seal the top after you trim the excess, and glue on the cover.
Walter Baron, Old Wharf Dory Co.
--- Inbolger@yahoogroups.com, Mark Albanese <marka97203@...> wrote:
http://www.shopmaninc.com/foam.html
Coast Guard regulations on flotation for boats under 20' state that the boat should have positive, level flotation. This eliminates any kind of sealed air chambers, bags, ping pong balls, etc. or any flotation not permanently installed, if you are going to pay attention to CG regs.
I have been using two part foam in sealed chambers in many boats over many years, and have not had any problems reported to me. Seal the interior with epoxy before you pour the foam, make sure the space is totally full, seal the top after you trim the excess, and glue on the cover.
Walter Baron, Old Wharf Dory Co.
>Yes. the two part marine flotation foams are closed cell- check this web page -
> On the other hand I think you'll find that all the two part pour in
> marine flotation foams are the closed cell type, similar to this.
>http://tinyurl.com/y96qsrx
>
>
> I've got some filling the ends of a ten year old, very neglected 16'
> sharpie. No rot. I filled the chambers before adding the deck so had
> to do a little trimming through its self generated crust, which
> seemed to require sealing. Light fiberglass is good, though the
> trimmed through cells looked like they'd use up an awful lot of
> epoxy. I used a coating of Snow Roof. The stuff does generate some
> mechanical force while expanding, but anything well built ought to
> hold up.
>
> I tested some once by holding it under water for a week with no
> addition in weight.
>
> It adds extra structural integrity.
>
> Air bags are also quite nice for the occasional spill.
>
> Mark
>
http://www.shopmaninc.com/foam.html
Coast Guard regulations on flotation for boats under 20' state that the boat should have positive, level flotation. This eliminates any kind of sealed air chambers, bags, ping pong balls, etc. or any flotation not permanently installed, if you are going to pay attention to CG regs.
I have been using two part foam in sealed chambers in many boats over many years, and have not had any problems reported to me. Seal the interior with epoxy before you pour the foam, make sure the space is totally full, seal the top after you trim the excess, and glue on the cover.
Walter Baron, Old Wharf Dory Co.
We've all kicked in our 2 cents and I might be guilty of giving a nickles worth but here's some more...
I am of the school of thought that any small sailboat boat, especially a sharpie can get knocked down. So once you've got her all together, I'd do a capsize test. I'd take her into the shallows and deliberately capsize her. Here's the procedure, get some buddies and some barley pops and anchor the bow and stern. Have your buddies hold her in place and then tie a line to the mast head and pull her over. You'll get a good idea how far she can heel, what it takes to right her, how much water she can ship, how she'll behave swamped, and how to get back in her to start bailing. You can make this a family adventure with the kids too.
John Boy
I am of the school of thought that any small sailboat boat, especially a sharpie can get knocked down. So once you've got her all together, I'd do a capsize test. I'd take her into the shallows and deliberately capsize her. Here's the procedure, get some buddies and some barley pops and anchor the bow and stern. Have your buddies hold her in place and then tie a line to the mast head and pull her over. You'll get a good idea how far she can heel, what it takes to right her, how much water she can ship, how she'll behave swamped, and how to get back in her to start bailing. You can make this a family adventure with the kids too.
John Boy
From:gbroadlick <GBroadlick@...>
To:bolger@yahoogroups.com
Sent:Wed, January 27, 2010 10:59:04 PM
Subject:[bolger] Flotation Help
I have built to plan a Parker Ohio Sharpie. The hull is ready to paint but the interior is not finished needing deck, seats, center board etc installed. I would like to use the boat for trips such as the Texas 200, Everglades challenge etc. The boat as drawn has no flotation. I could use some help determining how and where to place the flotation. My most recent idea is to create enclosed compartments in the bow and stern with a hatch for access, and to skin the inner surface of the frames creating a space between the hull and skin. I thought i would fill this space with 2 part urithane foam. This would create a closed space with no access. Is this a problem?
Location Displacement
Bow 1025 lb
Transom 850 lb
Port side 600 lb
Starbord side 600 lb
Total 3075 lb
http://www.parker-marine.com/parker2_3.htm
On the other hand I think you'll find that all the two part pour in marine flotation foams are the closed cell type, similar to this.
I've got some filling the ends of a ten year old, very neglected 16' sharpie. No rot. I filled the chambers before adding the deck so had to do a little trimming through its self generated crust, which seemed to require sealing. Light fiberglass is good, though the trimmed through cells looked like they'd use up an awful lot of epoxy. I used a coating of Snow Roof. The stuff does generate some mechanical force while expanding, but anything well built ought to hold up.
I tested some once by holding it under water for a week with no addition in weight.
It adds extra structural integrity.
Air bags are also quite nice for the occasional spill.
Mark
I don't think is a good idea for several reasons. 1 Compressing air will generate moisture. 2 Expanding air in cold weather from a nozzle will have the tendency to freeze around the nozzle and then the ice will melt and generate water in the compartment. 3 Pressurizing a compartment is a risky job, cracks may develop even with a minimum pressure. I witness large ocean going tankers having the deck lifted just for loading ballast water without venting the tank and also tanks imploded for discharging ballast without opening the vent. Giuliano --- OnThu, 1/28/10, Douglas Pollard<dougpol1@...>wrote:
|
I got yahoo'd here's my first post again.
John Boy
John Boy
----- Forwarded Message ----
From:John Huft <t1ro2003@...>
To:bolger@yahoogroups.com
Sent:Thu, January 28, 2010 6:56:09 AM
Subject:Re: [bolger] Flotation Help
From:gbroadlick <GBroadlick@...>
To:bolger@yahoogroups.com
Sent:Wed, January 27, 2010 10:59:04 PM
Subject:[bolger] Flotation Help
From:John Huft <t1ro2003@...>
To:bolger@yahoogroups.com
Sent:Thu, January 28, 2010 6:56:09 AM
Subject:Re: [bolger] Flotation Help
Here's some ball park ideas for flotation. Seawater weighs about 62 lbs/cubic foot, freshwater weighs about 60/cubic foot so air chambers will provide that much buoyancy per cubic foot. Foam will weigh in around 2 lbs per cubic foot so 1 cubic foot of foam will provide about 60 lbs of buoyancy in salt water. There are some formulas for ciphering it all out.
Here's a discussion I bogarted from a boat building group, I didn't attribute it when I copied it so I don't remember if it is from the Wooden Boat forum or Boat Building forum.
Here's my two cents about sealing flotation chambers in a plywood boat. Seal the inside of the chamber well with epoxy before filling it with foam. Paint is somewhat porous and water can and will soak into the wood and create conditions for rot and lamination failures. Even standing water as little as 1/4 will work its way through a flat roof over time. I'd also do my best to not have ANY air pockets between the foam and the structure of the boat. Voids are places where condensation can form and some foams can and will absorb water when exposed to it over time. Read your label. This will increase the weight of the foam and decrease the flotation ability over time. Some foams when allowed to stay wet will actually turn to heavy wet spongy dust over time. If you go with air chambers, I'd put some drain plugs and screw on deck plates in so you can inspect and allow the chamber to dry out.
I noticed you posted some weight and balance numbers for your boat. Now all you've got to do is some college level geometry to figure out where and how much flotation chambers to build. :-)
Have fun,
John Boy
BTW How 'bout some pics? We'd all like to see your boat.
Here's a discussion I bogarted from a boat building group, I didn't attribute it when I copied it so I don't remember if it is from the Wooden Boat forum or Boat Building forum.
"You
guys are scaring me.
I suggest to do it right or don't do it at all.
First use ABYC H-5 - Boat Load Capacity
Next ABYC H-8 - Buoyancy in the Event of Swamping
Both guidlines cover about 32 pages and give nice diagrams and examples. I haven't
worked with boats under 20' in a while but to summarize in general:
Capacity: Imagine the boat in the water with the scuppers sealed. Then add as
much weight as possible, distributed properly, to submerge the hull just to the
point where water is about to come over the sheer. This is called the static
float plane. The amount of weight you added will determine the capacity. The
book has formulas to estimate capacity at static float plane.
Floatation: You have three things you need to float, the boat, the engine and
the person capacity (includes gear).
The calculations are tedious but not difficult. Just follow it step by step. At
the risk of a copyright violation, from ABYC H-8:
H-8.7.2 Calculations - Basic Flotation
H-8.7.2.1 Perform the following steps to calculate the volume of flotation
material required to support the swamped boat (Fb), the submerged propulsion
equipment (Fp), the persons capacity (Fc1), and the dead weight (Fc2).
H-8.7.2.1.1 Step 1: Determine the flotation needed to support the swamped boat
(Fb).
Formula: Fb = (Wh x K1 + Wd x K2 + .69 We) ÷ B
Where
Wh = dry weight of hull, i.e., everything below swamped water line
Wd = dry weight of deck and superstructure
We = dry weight of factory installed equipment, hardware, and accessories
K1 and K2 = conversion factors for materials
used from Table I (See Note 1.)
B = buoyancy of flotation material in pounds per cubic foot
(NOTES DELETED)
EXAMPLE
Calculate the flotation material needed to support the swamped boat (Fb).
Assume
Wh = weight of hull (fiberglass) = 600 lbs.
Wd = weight of deck and superstructure (plywood) = 120 lbs.
We = weight of equipment, hardware and accessories = 50 lbs.
Fb = ((Wh x K1) + (Wd x K2 ) + (0.69 x 50)) ÷ B
Fb =((600x0.33)+ (120x-0.81) + 0.69x50)) ÷ 60.4*
Fb = (198 - 97.2 + 34.5) ÷ 60.4
Fb = 135.3 ÷ 60.4
Fb = 2.24 cu. ft.
*The figure for a two pound flotation material.
Next there are formulas to calculate the floatation for submerged propulsion
equipment, persons capacity and dead weight (gear).
Good luck.
djs"
Here's my two cents about sealing flotation chambers in a plywood boat. Seal the inside of the chamber well with epoxy before filling it with foam. Paint is somewhat porous and water can and will soak into the wood and create conditions for rot and lamination failures. Even standing water as little as 1/4 will work its way through a flat roof over time. I'd also do my best to not have ANY air pockets between the foam and the structure of the boat. Voids are places where condensation can form and some foams can and will absorb water when exposed to it over time. Read your label. This will increase the weight of the foam and decrease the flotation ability over time. Some foams when allowed to stay wet will actually turn to heavy wet spongy dust over time. If you go with air chambers, I'd put some drain plugs and screw on deck plates in so you can inspect and allow the chamber to dry out.
I noticed you posted some weight and balance numbers for your boat. Now all you've got to do is some college level geometry to figure out where and how much flotation chambers to build. :-)
Have fun,
John Boy
BTW How 'bout some pics? We'd all like to see your boat.
From:gbroadlick <GBroadlick@...>
To:bolger@yahoogroups.com
Sent:Wed, January 27, 2010 10:59:04 PM
Subject:[bolger] Flotation Help
I have built to plan a Parker Ohio Sharpie. The hull is ready to paint but the interior is not finished needing deck, seats, center board etc installed. I would like to use the boat for trips such as the Texas 200, Everglades challenge etc. The boat as drawn has no flotation. I could use some help determining how and where to place the flotation. My most recent idea is to create enclosed compartments in the bow and stern with a hatch for access, and to skin the inner surface of the frames creating a space between the hull and skin. I thought i would fill this space with 2 part urithane foam. This would create a closed space with no access. Is this a problem?
Location Displacement
Bow 1025 lb
Transom 850 lb
Port side 600 lb
Starbord side 600 lb
Total 3075 lb
http://www.parker-marine.com/parker2_3.htm
I'm with the Captain. :-)
John Boy
John Boy
From:John Weiss <jrweiss98155@...>
To:bolger@yahoogroups.com
Sent:Thu, January 28, 2010 2:32:37 PM
Subject:Re: [bolger] Re: Flotation Help
If you have any table tennis afficionado friends, ping pong balls would
work, too, and will more efficiently fill up the space. Otherwise, use
the small bottles so they pack more efficiently, and so you can insert &
retrieve them more easily through a standard inspection port.
May not be USCG approved, but will do the job!
BllFs6@...wrote:
>
> My plan would be this.
>
> Make the areas well sealed with an inspection hatch. Then fill those
> areas with empty plastic water/soda bottles.
>
>
> If the areas are not breached then you have lots of flotation. If they
> are breached, all those empty bottles will provide anywhere from 50 to
> 70 percent of the flotation that you would get if the whole thing was
> filled with foam.
>
> Cheap, very lightwieght, easy to inspect, wont trap water in there,
> adjustable, and easy to undo.
I'd got for empty bottles of Capt Morgan! ;-)
John Boy
John Boy
From:"BllFs6@..." <BllFs6@...>
To:bolger@yahoogroups.com
Sent:Thu, January 28, 2010 10:25:55 AM
Subject:Re: [bolger] Re: Flotation Help
Bravo! Doug
>
>
I wouldnt go quite that far. Just wait until you have to go collect all those thousands of bottles :)
take care
blll
I once used two part foam to remove a large indentation in a Hunter hull. Access was very limited and removing and reglassing very expensive. So we used a holesaw to access the area and poured in two part 2lb/cuft foam. It scared the hell out of me 'cause I was worried that it would catch fire, but the owner had signed a release, and we used small pours to keep the temp down. The hull still got pretty warm, but that worked to our advantage by making the glass more flexible.
Tom
Tom
--- Inbolger@yahoogroups.com, the doctor <scotedoc2@...> wrote:
>
> I would avoid the two part or spray in foams..... I have seen some that expanded as they matured doing structural damage.
> Â
> Expanded Polystyrene in blocks or sheets would be my choice. It doesn't absorb water and can be cut / fit in irregular spaces.
> Â
> I floated a 10000 sq. ft. marina as well as a 12x30 work barge on it.
> Â
> doc
>
> --- On Thu, 1/28/10, J.J. C1200 <jjc1200@...> wrote:
>
>
> From: J.J. C1200 <jjc1200@...>
> Subject: RE: [bolger] Re: Flotation Help
> To:bolger@yahoogroups.com
> Date: Thursday, January 28, 2010, 11:13 AM
>
>
> Â
>
>
>
> On early long distance flights they filled airplanes with ping pong ballsÂ
>
> > To: bolger@yahoogroups. com
> > From: dougpol1@verizon. net
> > Date: Thu, 28 Jan 2010 11:19:09 -0500
> > Subject: Re: [bolger] Re: Flotation Help
> >
> > BllFs6@... wrote:
> > >
> > >
> > > My plan would be this.
> > > Make the areas well sealed with an inspection hatch. Then fill those
> > > areas with empty plastic water/soda bottles.
> > > If the areas are not breached then you have lots of flotation. If they
> > > are breached, all those empty bottles will provide anywhere from 50 to
> > > 70 percent of the flotation that you would get if the whole thing was
> > > filled with foam.
> > > Cheap, very lightwieght, easy to inspect, wont trap water in there,
> > > adjustable, and easy to undo.
> > >
> > >
> > > Bravo! Doug
> > >
> > >
> >
> >
> >
> > ------------ --------- --------- ------
> >
> > Bolger rules!!!
> > - NO "GO AWAY SPAMMER!" posts!!! Please!
> > - no cursing, flaming, trolling, spamming, respamming, or flogging dead horses
> > - stay on topic, stay on thread, punctuate, no 'Ed, thanks, Fred' posts
> > - Pls add your comments at the TOP, SIGN your posts, and snip away
> > - Plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA, 01930, Fax: (978) 282-1349
> > - Unsubscribe: bolger-unsubscribe@ yahoogroups. com
> > - Open discussion: bolger_coffee_ lounge-subscribe @yahoogroups. com Yahoo! Groups Links
> >
> >
> >
>
>
>
> Hotmail: Free, trusted and rich email service. Get it now.
>
If you have any table tennis afficionado friends, ping pong balls would
work, too, and will more efficiently fill up the space. Otherwise, use
the small bottles so they pack more efficiently, and so you can insert &
retrieve them more easily through a standard inspection port.
May not be USCG approved, but will do the job!
BllFs6@...wrote:
work, too, and will more efficiently fill up the space. Otherwise, use
the small bottles so they pack more efficiently, and so you can insert &
retrieve them more easily through a standard inspection port.
May not be USCG approved, but will do the job!
BllFs6@...wrote:
>
> My plan would be this.
>
> Make the areas well sealed with an inspection hatch. Then fill those
> areas with empty plastic water/soda bottles.
>
>
> If the areas are not breached then you have lots of flotation. If they
> are breached, all those empty bottles will provide anywhere from 50 to
> 70 percent of the flotation that you would get if the whole thing was
> filled with foam.
>
> Cheap, very lightwieght, easy to inspect, wont trap water in there,
> adjustable, and easy to undo.
I would avoid the two part or spray in foams..... I have seen some that expanded as they matured doing structural damage. Expanded Polystyrene in blocks or sheets would be my choice. It doesn't absorb water and can be cut / fit in irregular spaces. I floated a 10000 sq. ft. marina as well as a 12x30 work barge on it. doc --- OnThu, 1/28/10, J.J. C1200<jjc1200@...>wrote:
|
Well, no wonder Pan Am went out of business!
Sarchasm(n): The gulf between the author of sarcastic wit and the person who doesn't get it.
From:J.J. C1200 <jjc1200@...>
To:bolger@yahoogroups.com
Sent:Thu, January 28, 2010 10:13:49 AM
Subject:RE: [bolger] Re: Flotation Help
Hotmail: Free, trusted and rich email service.Get it now.
From:J.J. C1200 <jjc1200@...>
To:bolger@yahoogroups.com
Sent:Thu, January 28, 2010 10:13:49 AM
Subject:RE: [bolger] Re: Flotation Help
On early long distance flights they filled airplanes with ping pong balls
> To: bolger@yahoogroups. comIndividual Email | Traditional
> From: dougpol1@verizon. net
> Date: Thu, 28 Jan 2010 11:19:09 -0500
> Subject: Re: [bolger] Re: Flotation Help
>
> BllFs6@... wrote:
> >
> >
> > My plan would be this.
> > Make the areas well sealed with an inspection hatch. Then fill those
> > areas with empty plastic water/soda bottles.
> > If the areas are not breached then you have lots of flotation. If they
> > are breached, all those empty bottles will provide anywhere from 50 to
> > 70 percent of the flotation that you would get if the whole thing was
> > filled with foam.
> > Cheap, very lightwieght, easy to inspect, wont trap water in there,
> > adjustable, and easy to undo.
> >
> >
> > Bravo! Doug
> >
> >
>
>
>
> ------------ --------- --------- ------
>
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On early long distance flights they filled airplanes with ping pong balls
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> To: bolger@yahoogroups.com
> From: dougpol1@...
> Date: Thu, 28 Jan 2010 11:19:09 -0500
> Subject: Re: [bolger] Re: Flotation Help
>
> BllFs6@... wrote:
> >
> >
> > My plan would be this.
> > Make the areas well sealed with an inspection hatch. Then fill those
> > areas with empty plastic water/soda bottles.
> > If the areas are not breached then you have lots of flotation. If they
> > are breached, all those empty bottles will provide anywhere from 50 to
> > 70 percent of the flotation that you would get if the whole thing was
> > filled with foam.
> > Cheap, very lightwieght, easy to inspect, wont trap water in there,
> > adjustable, and easy to undo.
> >
> >
> > Bravo! Doug
> >
> >
>
>
>
> ------------------------------------
>
> Bolger rules!!!
> - NO "GO AWAY SPAMMER!" posts!!! Please!
> - no cursing, flaming, trolling, spamming, respamming, or flogging dead horses
> - stay on topic, stay on thread, punctuate, no 'Ed, thanks, Fred' posts
> - Pls add your comments at the TOP, SIGN your posts, and snip away
> - Plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA, 01930, Fax: (978) 282-1349
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The reason that two-part expanding foams absorb water is that they are open-celled foams, like a sponge. It absorbs water by the same mechanism. The pink/blue extruded polystyrene insulation foam, OTOH, is closed-cell and therefore will not absorb water because there is no path for it to go from the surface inward.
-p
On Thu, Jan 28, 2010 at 5:41 AM, Tom<tomseigler@...>wrote:Gene is right. Moisture will be absorbed by two part foam even if it is in a sealed compartment. The water molecule is called the "universal solvent" because it is so small it can pass thru anything. Once the moisture condensates inside a sealed area, it stays there. Even with the boat out of the water, moisture will condensate inside a sealed area and continue to collect until the foam is saturated.
Tom
--- Inbolger@yahoogroups.com, Gene Tehansky <goldranger02-boats@...> wrote:
>
> I personally have seen that 2 part foam absorbs and holds water. It
> was a fiberglass boat so it was just an inconvenience lifting out the
> massive blocks of foam. And sloppy. You are much better off with the
> blue stuff (or pink) and letting air circulate around it to keep the
> wood dry. You will never truly be able to seal the 2 part foam in so
> it will get water and even if the wood is sealed, cracks will form and
> you will get rot. Don't do it! Keep asking around...
>
> Sincerely,
> Gene T.
>
> On 28 Jan, 2010, at 7:37 AM, John and Kathy Trussell wrote:
>
> >
> > There are a lot of different views on flotation. In general,
> > flotation up high is better than flotation down low. In general,
> > enclosed "flotation tanks" serve to limit the amount of water which
> > a boat will hold when it is capsized or swamped. At various times, I
> > have used blue insulation foam cut to fit and stacked in the ends of
> > a boat (under a deck), swimming pool "noodles", airbags, and sealed
> > chambers (which were accessed by Beckson ports—not home made hatches
> > which are difficult to make water tight). I don't see why a 2 part
> > foam wouldn't work, but I would suggest that you make an effort to
> > seal the adjoining wood before you install the foam to eliminate
> > potential rot traps.
> >
> >
> >
> > Have fun.
> >
> >
> >
> > JohnT
> >
> >
> >
> > From:bolger@yahoogroups.com[mailto:bolger@yahoogroups.com] On
> > Behalf Of gbroadlick
> > Sent: Wednesday, January 27, 2010 11:59 PM
> > To:bolger@yahoogroups.com
> > Subject: [bolger] Flotation Help
> >
> >
> >
> >
> >
> >
> > I have built to plan a Parker Ohio Sharpie. The hull is ready to
> > paint but the interior is not finished needing deck, seats, center
> > board etc installed. I would like to use the boat for trips such as
> > the Texas 200, Everglades challenge etc. The boat as drawn has no
> > flotation. I could use some help determining how and where to place
> > the flotation. My most recent idea is to create enclosed
> > compartments in the bow and stern with a hatch for access, and to
> > skin the inner surface of the frames creating a space between the
> > hull and skin. I thought i would fill this space with 2 part
> > urithane foam. This would create a closed space with no access. Is
> > this a problem?
> >
> > Location Displacement
> > Bow 1025 lb
> > Transom 850 lb
> > Port side 600 lb
> > Starbord side 600 lb
> > Total 3075 lb
> >http://www.parker-marine.com/parker2_3.htm
> >
> > No virus found in this incoming message.
> > Checked by AVG -www.avg.com
> > Version: 9.0.733 / Virus Database: 271.1.1/2650 - Release Date:
> > 01/27/10 14:36:00
> >
> >
> >
>
------------------------------------
Bolger rules!!!
- NO "GO AWAY SPAMMER!" posts!!! Please!
- no cursing, flaming, trolling, spamming, respamming, or flogging dead horses
- stay on topic, stay on thread, punctuate, no 'Ed, thanks, Fred' posts
- Pls add your comments at the TOP, SIGN your posts, and snip away
- Plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA, 01930, Fax: (978) 282-1349
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Bravo! Doug > >
I wouldnt go quite that far. Just wait until you have to go collect all those thousands of bottles :)
take care
blll
BllFs6@...wrote:
>
>
> My plan would be this.
> Make the areas well sealed with an inspection hatch. Then fill those
> areas with empty plastic water/soda bottles.
> If the areas are not breached then you have lots of flotation. If they
> are breached, all those empty bottles will provide anywhere from 50 to
> 70 percent of the flotation that you would get if the whole thing was
> filled with foam.
> Cheap, very lightwieght, easy to inspect, wont trap water in there,
> adjustable, and easy to undo.
>
>
> Bravo! Doug
>
>
My plan would be this.
Make the areas well sealed with an inspection hatch. Then fill those areas with empty plastic water/soda bottles.
If the areas are not breached then you have lots of flotation. If they are breached, all those empty bottles will provide anywhere from 50 to 70 percent of the flotation that you would get if the whole thing was filled with foam.
Cheap, very lightwieght, easy to inspect, wont trap water in there, adjustable, and easy to undo.
Sorry guys, that was a dumb idea. Doug
Douglas Pollard wrote:
Douglas Pollard wrote:
> I have wondered if it might not be possible to in ject a small amount of
> airpressure into a block of sealed foam to maintain a positive pressure
> to keep water out. A cylinder and piston with a weight on it could be
> used to pressurize the foam. Of course the injected air would need to be
> dry. The piston might be lifted and released to re pressurize the foam
> every now and then. Some simpler variation of this might work. Doug
>
>
> Tom wrote:
>
>> Gene is right. Moisture will be absorbed by two part foam even if it
>> is in a sealed compartment. The water molecule is called the
>> "universal solvent" because it is so small it can pass thru anything.
>> Once the moisture condensates inside a sealed area, it stays there.
>> Even with the boat out of the water, moisture will condensate inside a
>> sealed area and continue to collect until the foam is saturated.
>>
>> Tom
>>
>> --- Inbolger@yahoogroups.com<mailto:bolger%40yahoogroups.com>, Gene
>> Tehansky <goldranger02-boats@...> wrote:
>>
>>> I personally have seen that 2 part foam absorbs and holds water. It
>>> was a fiberglass boat so it was just an inconvenience lifting out the
>>> massive blocks of foam. And sloppy. You are much better off with the
>>> blue stuff (or pink) and letting air circulate around it to keep the
>>> wood dry. You will never truly be able to seal the 2 part foam in so
>>> it will get water and even if the wood is sealed, cracks will form and
>>> you will get rot. Don't do it! Keep asking around...
>>>
>>> Sincerely,
>>> Gene T.
>>>
>>> On 28 Jan, 2010, at 7:37 AM, John and Kathy Trussell wrote:
>>>
>>>
>>>> There are a lot of different views on flotation. In general,
>>>> flotation up high is better than flotation down low. In general,
>>>> enclosed "flotation tanks" serve to limit the amount of water which
>>>> a boat will hold when it is capsized or swamped. At various times, I
>>>> have used blue insulation foam cut to fit and stacked in the ends of
>>>> a boat (under a deck), swimming pool "noodles", airbags, and sealed
>>>> chambers (which were accessed by Beckson ports—not home made hatches
>>>> which are difficult to make water tight). I don't see why a 2 part
>>>> foam wouldn't work, but I would suggest that you make an effort to
>>>> seal the adjoining wood before you install the foam to eliminate
>>>> potential rot traps.
>>>>
>>>>
>>>>
>>>> Have fun.
>>>>
>>>>
>>>>
>>>> JohnT
>>>>
>>>>
>>>>
>>>> From:bolger@yahoogroups.com<mailto:bolger%40yahoogroups.com>
>>>>
>> [mailto:bolger@yahoogroups.com<mailto:bolger%40yahoogroups.com>] On
>>
>>>> Behalf Of gbroadlick
>>>> Sent: Wednesday, January 27, 2010 11:59 PM
>>>> To:bolger@yahoogroups.com<mailto:bolger%40yahoogroups.com>
>>>> Subject: [bolger] Flotation Help
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> I have built to plan a Parker Ohio Sharpie. The hull is ready to
>>>> paint but the interior is not finished needing deck, seats, center
>>>> board etc installed. I would like to use the boat for trips such as
>>>> the Texas 200, Everglades challenge etc. The boat as drawn has no
>>>> flotation. I could use some help determining how and where to place
>>>> the flotation. My most recent idea is to create enclosed
>>>> compartments in the bow and stern with a hatch for access, and to
>>>> skin the inner surface of the frames creating a space between the
>>>> hull and skin. I thought i would fill this space with 2 part
>>>> urithane foam. This would create a closed space with no access. Is
>>>> this a problem?
>>>>
>>>> Location Displacement
>>>> Bow 1025 lb
>>>> Transom 850 lb
>>>> Port side 600 lb
>>>> Starbord side 600 lb
>>>> Total 3075 lb
>>>>http://www.parker-marine.com/parker2_3.htm
>>>>
>> <http://www.parker-marine.com/parker2_3.htm>
>>
>>>> No virus found in this incoming message.
>>>> Checked by AVG - www.avg.com
>>>> Version: 9.0.733 / Virus Database: 271.1.1/2650 - Release Date:
>>>> 01/27/10 14:36:00
>>>>
>>>>
>>>>
>>>>
>>
>
>
>
> ------------------------------------
>
> Bolger rules!!!
> - NO "GO AWAY SPAMMER!" posts!!! Please!
> - no cursing, flaming, trolling, spamming, respamming, or flogging dead horses
> - stay on topic, stay on thread, punctuate, no 'Ed, thanks, Fred' posts
> - Pls add your comments at the TOP, SIGN your posts, and snip away
> - Plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA, 01930, Fax: (978) 282-1349
> - Unsubscribe:bolger-unsubscribe@yahoogroups.com
> - Open discussion:bolger_coffee_lounge-subscribe@yahoogroups.comYahoo! Groups Links
>
>
>
>
>
I have wondered if it might not be possible to in ject a small amount of
airpressure into a block of sealed foam to maintain a positive pressure
to keep water out. A cylinder and piston with a weight on it could be
used to pressurize the foam. Of course the injected air would need to be
dry. The piston might be lifted and released to re pressurize the foam
every now and then. Some simpler variation of this might work. Doug
Tom wrote:
airpressure into a block of sealed foam to maintain a positive pressure
to keep water out. A cylinder and piston with a weight on it could be
used to pressurize the foam. Of course the injected air would need to be
dry. The piston might be lifted and released to re pressurize the foam
every now and then. Some simpler variation of this might work. Doug
Tom wrote:
>
> Gene is right. Moisture will be absorbed by two part foam even if it
> is in a sealed compartment. The water molecule is called the
> "universal solvent" because it is so small it can pass thru anything.
> Once the moisture condensates inside a sealed area, it stays there.
> Even with the boat out of the water, moisture will condensate inside a
> sealed area and continue to collect until the foam is saturated.
>
> Tom
>
> --- Inbolger@yahoogroups.com<mailto:bolger%40yahoogroups.com>, Gene
> Tehansky <goldranger02-boats@...> wrote:
> >
> > I personally have seen that 2 part foam absorbs and holds water. It
> > was a fiberglass boat so it was just an inconvenience lifting out the
> > massive blocks of foam. And sloppy. You are much better off with the
> > blue stuff (or pink) and letting air circulate around it to keep the
> > wood dry. You will never truly be able to seal the 2 part foam in so
> > it will get water and even if the wood is sealed, cracks will form and
> > you will get rot. Don't do it! Keep asking around...
> >
> > Sincerely,
> > Gene T.
> >
> > On 28 Jan, 2010, at 7:37 AM, John and Kathy Trussell wrote:
> >
> > >
> > > There are a lot of different views on flotation. In general,
> > > flotation up high is better than flotation down low. In general,
> > > enclosed "flotation tanks" serve to limit the amount of water which
> > > a boat will hold when it is capsized or swamped. At various times, I
> > > have used blue insulation foam cut to fit and stacked in the ends of
> > > a boat (under a deck), swimming pool "noodles", airbags, and sealed
> > > chambers (which were accessed by Beckson ports—not home made hatches
> > > which are difficult to make water tight). I don't see why a 2 part
> > > foam wouldn't work, but I would suggest that you make an effort to
> > > seal the adjoining wood before you install the foam to eliminate
> > > potential rot traps.
> > >
> > >
> > >
> > > Have fun.
> > >
> > >
> > >
> > > JohnT
> > >
> > >
> > >
> > > From:bolger@yahoogroups.com<mailto:bolger%40yahoogroups.com>
> [mailto:bolger@yahoogroups.com<mailto:bolger%40yahoogroups.com>] On
> > > Behalf Of gbroadlick
> > > Sent: Wednesday, January 27, 2010 11:59 PM
> > > To:bolger@yahoogroups.com<mailto:bolger%40yahoogroups.com>
> > > Subject: [bolger] Flotation Help
> > >
> > >
> > >
> > >
> > >
> > >
> > > I have built to plan a Parker Ohio Sharpie. The hull is ready to
> > > paint but the interior is not finished needing deck, seats, center
> > > board etc installed. I would like to use the boat for trips such as
> > > the Texas 200, Everglades challenge etc. The boat as drawn has no
> > > flotation. I could use some help determining how and where to place
> > > the flotation. My most recent idea is to create enclosed
> > > compartments in the bow and stern with a hatch for access, and to
> > > skin the inner surface of the frames creating a space between the
> > > hull and skin. I thought i would fill this space with 2 part
> > > urithane foam. This would create a closed space with no access. Is
> > > this a problem?
> > >
> > > Location Displacement
> > > Bow 1025 lb
> > > Transom 850 lb
> > > Port side 600 lb
> > > Starbord side 600 lb
> > > Total 3075 lb
> > >http://www.parker-marine.com/parker2_3.htm
> <http://www.parker-marine.com/parker2_3.htm>
> > >
> > > No virus found in this incoming message.
> > > Checked by AVG - www.avg.com
> > > Version: 9.0.733 / Virus Database: 271.1.1/2650 - Release Date:
> > > 01/27/10 14:36:00
> > >
> > >
> > >
> >
>
>
Gene is right. Moisture will be absorbed by two part foam even if it is in a sealed compartment. The water molecule is called the "universal solvent" because it is so small it can pass thru anything. Once the moisture condensates inside a sealed area, it stays there. Even with the boat out of the water, moisture will condensate inside a sealed area and continue to collect until the foam is saturated.
Tom
Tom
--- Inbolger@yahoogroups.com, Gene Tehansky <goldranger02-boats@...> wrote:
>
> I personally have seen that 2 part foam absorbs and holds water. It
> was a fiberglass boat so it was just an inconvenience lifting out the
> massive blocks of foam. And sloppy. You are much better off with the
> blue stuff (or pink) and letting air circulate around it to keep the
> wood dry. You will never truly be able to seal the 2 part foam in so
> it will get water and even if the wood is sealed, cracks will form and
> you will get rot. Don't do it! Keep asking around...
>
> Sincerely,
> Gene T.
>
> On 28 Jan, 2010, at 7:37 AM, John and Kathy Trussell wrote:
>
> >
> > There are a lot of different views on flotation. In general,
> > flotation up high is better than flotation down low. In general,
> > enclosed "flotation tanks" serve to limit the amount of water which
> > a boat will hold when it is capsized or swamped. At various times, I
> > have used blue insulation foam cut to fit and stacked in the ends of
> > a boat (under a deck), swimming pool "noodles", airbags, and sealed
> > chambers (which were accessed by Beckson portsnot home made hatches
> > which are difficult to make water tight). I don't see why a 2 part
> > foam wouldn't work, but I would suggest that you make an effort to
> > seal the adjoining wood before you install the foam to eliminate
> > potential rot traps.
> >
> >
> >
> > Have fun.
> >
> >
> >
> > JohnT
> >
> >
> >
> > From:bolger@yahoogroups.com[mailto:bolger@yahoogroups.com] On
> > Behalf Of gbroadlick
> > Sent: Wednesday, January 27, 2010 11:59 PM
> > To:bolger@yahoogroups.com
> > Subject: [bolger] Flotation Help
> >
> >
> >
> >
> >
> >
> > I have built to plan a Parker Ohio Sharpie. The hull is ready to
> > paint but the interior is not finished needing deck, seats, center
> > board etc installed. I would like to use the boat for trips such as
> > the Texas 200, Everglades challenge etc. The boat as drawn has no
> > flotation. I could use some help determining how and where to place
> > the flotation. My most recent idea is to create enclosed
> > compartments in the bow and stern with a hatch for access, and to
> > skin the inner surface of the frames creating a space between the
> > hull and skin. I thought i would fill this space with 2 part
> > urithane foam. This would create a closed space with no access. Is
> > this a problem?
> >
> > Location Displacement
> > Bow 1025 lb
> > Transom 850 lb
> > Port side 600 lb
> > Starbord side 600 lb
> > Total 3075 lb
> >http://www.parker-marine.com/parker2_3.htm
> >
> > No virus found in this incoming message.
> > Checked by AVG - www.avg.com
> > Version: 9.0.733 / Virus Database: 271.1.1/2650 - Release Date:
> > 01/27/10 14:36:00
> >
> >
> >
>
Here's some ball park ideas for flotation. Seawater weighs about 62 lbs/cubic foot, freshwater weighs about 60/cubic foot so air chambers will provide that much buoyancy per cubic foot. Foam will weigh in around 2 lbs per cubic foot so 1 cubic foot of foam will provide about 60 lbs of buoyancy in salt water. There are some formulas for ciphering it all out.
Here's a discussion I bogarted from a boat building group, I didn't attribute it when I copied it so I don't remember if it is from the Wooden Boat forum or Boat Building forum.
Here's my two cents about sealing flotation chambers in a plywood boat. Seal the inside of the chamber well with epoxy before filling it with foam. Paint is somewhat porous and water can and will soak into the wood and create conditions for rot and lamination failures. Even standing water as little as 1/4 will work its way through a flat roof over time. I'd also do my best to not have ANY air pockets between the foam and the structure of the boat. Voids are places where condensation can form and some foams can and will absorb water when exposed to it over time. Read your label. This will increase the weight of the foam and decrease the flotation ability over time. Some foams when allowed to stay wet will actually turn to heavy wet spongy dust over time. If you go with air chambers, I'd put some drain plugs and screw on deck plates in so you can inspect and allow the chamber to dry out.
I noticed you posted some weight and balance numbers for your boat. Now all you've got to do is some college level geometry to figure out where and how much flotation chambers to build. :-)
Have fun,
John Boy
BTW How 'bout some pics? We'd all like to see your boat.
Here's a discussion I bogarted from a boat building group, I didn't attribute it when I copied it so I don't remember if it is from the Wooden Boat forum or Boat Building forum.
"You
guys are scaring me.
I suggest to do it right or don't do it at all.
First use ABYC H-5 - Boat Load Capacity
Next ABYC H-8 - Buoyancy in the Event of Swamping
Both guidlines cover about 32 pages and give nice diagrams and examples. I haven't
worked with boats under 20' in a while but to summarize in general:
Capacity: Imagine the boat in the water with the scuppers sealed. Then add as
much weight as possible, distributed properly, to submerge the hull just to the
point where water is about to come over the sheer. This is called the static
float plane. The amount of weight you added will determine the capacity. The
book has formulas to estimate capacity at static float plane.
Floatation: You have three things you need to float, the boat, the engine and
the person capacity (includes gear).
The calculations are tedious but not difficult. Just follow it step by step. At
the risk of a copyright violation, from ABYC H-8:
H-8.7.2 Calculations - Basic Flotation
H-8.7.2.1 Perform the following steps to calculate the volume of flotation
material required to support the swamped boat (Fb), the submerged propulsion
equipment (Fp), the persons capacity (Fc1), and the dead weight (Fc2).
H-8.7.2.1.1 Step 1: Determine the flotation needed to support the swamped boat
(Fb).
Formula: Fb = (Wh x K1 + Wd x K2 + .69 We) ÷ B
Where
Wh = dry weight of hull, i.e., everything below swamped water line
Wd = dry weight of deck and superstructure
We = dry weight of factory installed equipment, hardware, and accessories
K1 and K2 = conversion factors for materials
used from Table I (See Note 1.)
B = buoyancy of flotation material in pounds per cubic foot
(NOTES DELETED)
EXAMPLE
Calculate the flotation material needed to support the swamped boat (Fb).
Assume
Wh = weight of hull (fiberglass) = 600 lbs.
Wd = weight of deck and superstructure (plywood) = 120 lbs.
We = weight of equipment, hardware and accessories = 50 lbs.
Fb = ((Wh x K1) + (Wd x K2 ) + (0.69 x 50)) ÷ B
Fb =((600x0.33)+ (120x-0.81) + 0.69x50)) ÷ 60.4*
Fb = (198 - 97.2 + 34.5) ÷ 60.4
Fb = 135.3 ÷ 60.4
Fb = 2.24 cu. ft.
*The figure for a two pound flotation material.
Next there are formulas to calculate the floatation for submerged propulsion
equipment, persons capacity and dead weight (gear).
Good luck.
djs"
Here's my two cents about sealing flotation chambers in a plywood boat. Seal the inside of the chamber well with epoxy before filling it with foam. Paint is somewhat porous and water can and will soak into the wood and create conditions for rot and lamination failures. Even standing water as little as 1/4 will work its way through a flat roof over time. I'd also do my best to not have ANY air pockets between the foam and the structure of the boat. Voids are places where condensation can form and some foams can and will absorb water when exposed to it over time. Read your label. This will increase the weight of the foam and decrease the flotation ability over time. Some foams when allowed to stay wet will actually turn to heavy wet spongy dust over time. If you go with air chambers, I'd put some drain plugs and screw on deck plates in so you can inspect and allow the chamber to dry out.
I noticed you posted some weight and balance numbers for your boat. Now all you've got to do is some college level geometry to figure out where and how much flotation chambers to build. :-)
Have fun,
John Boy
BTW How 'bout some pics? We'd all like to see your boat.
From:gbroadlick <GBroadlick@...>
To:bolger@yahoogroups.com
Sent:Wed, January 27, 2010 10:59:04 PM
Subject:[bolger] Flotation Help
I have built to plan a Parker Ohio Sharpie. The hull is ready to paint but the interior is not finished needing deck, seats, center board etc installed. I would like to use the boat for trips such as the Texas 200, Everglades challenge etc. The boat as drawn has no flotation. I could use some help determining how and where to place the flotation. My most recent idea is to create enclosed compartments in the bow and stern with a hatch for access, and to skin the inner surface of the frames creating a space between the hull and skin. I thought i would fill this space with 2 part urithane foam. This would create a closed space with no access. Is this a problem?
Location Displacement
Bow 1025 lb
Transom 850 lb
Port side 600 lb
Starbord side 600 lb
Total 3075 lb
http://www.parker-marine.com/parker2_3.htm
I personally have seen that 2 part foam absorbs and holds water. It was a fiberglass boat so it was just an inconvenience lifting out the massive blocks of foam. And sloppy. You are much better off with the blue stuff (or pink) and letting air circulate around it to keep the wood dry. You will never truly be able to seal the 2 part foam in so it will get water and even if the wood is sealed, cracks will form and you will get rot. Don't do it! Keep asking around...
Sincerely,
Gene T.
On 28 Jan, 2010, at 7:37 AM, John and Kathy Trussell wrote:
There are a lot of different views on flotation. In general, flotation up high is better than flotation down low. In general, enclosed “flotation tanks” serve to limit the amount of water which a boat will hold when it is capsized or swamped. At various times, I have used blue insulation foam cut to fit and stacked in the ends of a boat (under a deck), swimming pool “noodles”, airbags, and sealed chambers (which were accessed by Beckson ports—not home made hatches which are difficult to make water tight). I don’t see why a 2 part foam wouldn’t work, but I would suggest that you make an effort to seal the adjoining wood before you install the foam to eliminate potential rot traps.
Have fun.
JohnT
From: bolger@yahoogroups. com [mailto: bolger@yahoogroups. com ] On Behalf Of gbroadlick
Sent: Wednesday, January 27, 2010 11:59 PM
To: bolger@yahoogroups. com
Subject: [bolger] Flotation Help
I have built to plan a Parker Ohio Sharpie. The hull is ready to paint but the interior is not finished needing deck, seats, center board etc installed. I would like to use the boat for trips such as the Texas 200, Everglades challenge etc. The boat as drawn has no flotation. I could use some help determining how and where to place the flotation. My most recent idea is to create enclosed compartments in the bow and stern with a hatch for access, and to skin the inner surface of the frames creating a space between the hull and skin. I thought i would fill this space with 2 part urithane foam. This would create a closed space with no access. Is this a problem?
Location Displacement
Bow 1025 lb
Transom 850 lb
Port side 600 lb
Starbord side 600 lb
Total 3075 lb
http://www.parker- marine.com/ parker2_3. htmNo virus found in this incoming message.
Checked by AVG - www.avg.com
Version: 9.0.733 / Virus Database: 271.1.1/2650 - Release Date: 01/27/10 14:36:00
There are a lot of different views on flotation. In general, flotation up high is better than flotation down low. In general, enclosed “flotation tanks” serve to limit the amount of water which a boat will hold when it is capsized or swamped. At various times, I have used blue insulation foam cut to fit and stacked in the ends of a boat (under a deck), swimming pool “noodles”, airbags, and sealed chambers (which were accessed by Beckson ports—not home made hatches which are difficult to make water tight). I don’t see why a 2 part foam wouldn’t work, but I would suggest that you make an effort to seal the adjoining wood before you install the foam to eliminate potential rot traps.
Have fun.
JohnT
From:bolger@yahoogroups.com [mailto:
bolger@yahoogroups.com ]On Behalf Ofgbroadlick
Sent:Wednesday, January 27, 2010
11:59 PM
To:bolger@yahoogroups.com
Subject:[bolger] Flotation Help
I have built to plan a Parker Ohio Sharpie. The hull is ready to paint but the
interior is not finished needing deck, seats, center board etc installed. I
would like to use the boat for trips such as the Texas
200, Everglades challenge etc. The boat as drawn
has no flotation. I could use some help determining how and where to place the
flotation. My most recent idea is to create enclosed compartments in the bow
and stern with a hatch for access, and to skin the inner surface of the frames
creating a space between the hull and skin. I thought i would fill this space
with 2 part urithane foam. This would create a closed space with no access. Is
this a problem?
Location Displacement
Bow 1025 lb
Transom 850 lb
Port side 600 lb
Starbord side 600 lb
Total 3075 lb
http://www.parker- marine.com/ parker2_3. htm
No virus found in this incoming message.
Checked by AVG - www.avg.com
Version: 9.0.733 / Virus Database: 271.1.1/2650 - Release Date: 01/27/10 14:36:00
I have built to plan a Parker Ohio Sharpie. The hull is ready to paint but the interior is not finished needing deck, seats, center board etc installed. I would like to use the boat for trips such as the Texas 200, Everglades challenge etc. The boat as drawn has no flotation. I could use some help determining how and where to place the flotation. My most recent idea is to create enclosed compartments in the bow and stern with a hatch for access, and to skin the inner surface of the frames creating a space between the hull and skin. I thought i would fill this space with 2 part urithane foam. This would create a closed space with no access. Is this a problem?
Location Displacement
Bow 1025 lb
Transom 850 lb
Port side 600 lb
Starbord side 600 lb
Total 3075 lb
http://www.parker-marine.com/parker2_3.htm
Location Displacement
Bow 1025 lb
Transom 850 lb
Port side 600 lb
Starbord side 600 lb
Total 3075 lb
http://www.parker-marine.com/parker2_3.htm