Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 30-11-2009, 13:31   #31
Senior Cruiser
 
senormechanico's Avatar

Cruisers Forum Supporter

Join Date: Aug 2003
Boat: Dragonfly 1000 trimaran
Posts: 5,830
Quote:
Originally Posted by Ex-Calif View Post
"Fun read"? These people must really have a good sense of humor to make getting run over by a freighter a fun read...
They're our next door neighbors. If you knew them (or if you read the book), you'd understand. It's about a lot more than just the mid ocean collision.

Nowhere does it say anything like your "propeller bisected the cat" quote.
__________________

__________________
Memento,homo, quia pulvis es, et in pulverem reverteris.
senormechanico is offline   Reply With Quote
Old 02-12-2009, 12:08   #32
Registered User
 
denverd0n's Avatar

Join Date: Jun 2008
Location: Tampa, FL
Posts: 3,953
Images: 6
There are practically NO monohulls out there today, capable of offshore cruising, that are unsinkable. Not that no one has tried. Many have. None have been successful enough to make it commercially viable. None have been successful enough to make it a popular after-market modification. None have been successful enough to even gain any real recognition.

If you can succeed where all the others have failed, more power to you. You could probably write a book about it and make a fortune. I honestly don't wish to offend, but the much more likely outcome is that you will waste a lot of time, effort, and money doing nothing more than duplicating the failures of all of those others.

The choice is yours.
__________________

__________________
denverd0n is offline   Reply With Quote
Old 02-12-2009, 14:02   #33
Registered User
 
trinescape's Avatar

Join Date: Jun 2008
Location: adelaide ,australia
Boat: 36ft one off trimiran
Posts: 133
the name of the inflatable bags that keep you afloat is from the company called ''float pak'' and if i remember the review spoke very highly of them they are fixed in position in your vessel and if you pull a cord it inflates in seconds and you and your vessel are saved it was advertised in australian yachting magazines hope this helps regards andy
__________________
trinescape is offline   Reply With Quote
Old 02-12-2009, 16:13   #34
Registered User

Join Date: Dec 2007
Location: Duluth,Minnesota
Boat: Lindenberg 26 & Aloha 8.2
Posts: 984
I believe the airbag system was called "crewsaver" in the US but i dont think they are still available,i think this is what the Pardeys have on Taleisen,it inflates just like a liferaft. There was a Macgregor 36 cat that put the floatation to the test a few years back in the open ocean. It was on a solo voyage across the atlantic from the US to Europe and was hit by a fishing trawler in the fog while about 500 miles from Ireland,the collision broke off a couple of feet of the bow of one hull,the skipper Hal Andersen was able to fill the hole with sails etc and then continue on unaided.(The trawler lurked in the distance without giving assistance)and without fear of sinking.Ill bet he was thankfull for all that foam.
Steve.
__________________
clockwork orange is offline   Reply With Quote
Old 02-12-2009, 19:25   #35
Registered User
 
muskoka's Avatar

Join Date: Jun 2006
Location: Sai Kung, Hong Kong
Boat: FP Lavezzi 40 / Hatteras 48
Posts: 775
ETAP - Unsinkable Sailing Pleasure

Etap makes a range of monohulls from 21 to 46 feet which are certified unsinkable by the Europeans. I've been on a number of them at boat shows and it's impossible to discern any visible difference between an Etap and similar (sinkable) competitor - they seem to have been rather clever at distributing the insulation throughout the hulls to provide maximum interior space and safety. They also sail very well - the Etap 39 won a number of "Boat of the Year" awards a few years back.

I'm not sure how you would best go about refitting an existing hull but the principle of providing a monohull with positive buoyancy is certainly sound. And Etap have been doing it for 20+ years so it is also commercially viable!
__________________
muskoka is offline   Reply With Quote
Old 20-12-2009, 00:14   #36
Registered User
 
boat_alexandra's Avatar

Join Date: Aug 2009
Location: chesapeake bay
Boat: bristol 27
Posts: 2,811
So for an update, I got a truckload of large styrofoam blocks delivered to me for $450. I am pretty sure it should have cost around $300-$350, but this way it got done faster (same day). The total volume was 90 cubic feet, but I managed to get a bunch of free styrofoam to give me more than 100 cubic feet. Some pieces are glassed in which is perfect for facing against holes. I am going to give up all standing room except one spot where I can cook (instead of the length of the boat.)

I can manage to live on my boat with all the foam on it before it is even stored, so I think this is going to work fine, and the added insulation is a bonus.

I think most displacement boats could be made unsinkable just because they have so much space in them that is air. If you cut down on area you can move around in, you have just as much (or more storage) as well as all the foam.

I might still get some pour foam to fill the cracks and help "glue" everything together, thought I will not likely need much of it. If there is a leak, I can rip styrofoam out quite easily with my hands to get to it.
__________________
boat_alexandra is offline   Reply With Quote
Old 20-12-2009, 02:15   #37
Registered User

Join Date: Feb 2009
Posts: 1,321
Quote:
Originally Posted by muskoka View Post
ETAP - Unsinkable Sailing Pleasure

Etap makes a range of monohulls from 21 to 46 feet which are certified unsinkable by the Europeans.
I remember one of their tests on one of the largest models. Before flooding the boat they did remove some heavy items. Once flooded, the deck was awash with people standing on it, the boat was no more than just a raft. Not every body was impressed.
__________________
chala is offline   Reply With Quote
Old 20-12-2009, 02:50   #38
Registered User
 
Laidback's Avatar

Join Date: Jun 2007
Posts: 853
Quote:
Originally Posted by Quads View Post
The only boat that is "unsinkable" is the boat that is on the hard.

You really, *really* need to get grounded first with some good education and something to dilute this imaginary idea of carrying foam blocks to prevent you from sinking while you patch a hull underwater, and using that as an alternative to a proper life raft, should there be an emergency of some sort. How much money are you willing to spend to save your life?

If you do none of the above, and hit the water, let's hope that Darwin takes the day off, and please, don't take anyone on your boat with you.
The above is unfortunately a type of post that does very little to assist the creator of the thread, it comes across as patronizing and belittling.
Thanks to all the other posters who least contributed reasonable and courteous debate.
__________________
Laidback is offline   Reply With Quote
Old 20-12-2009, 05:30   #39
Registered User

Join Date: Feb 2009
Posts: 1,321
Just Googling up Bristol 27 I found displacement 6600 lbs.
6600 lbs = 2993.71 kg = 2.99371 m3 = 105.7219 cubic feet. =/- Adjustment for salt water and weight of foam this does not leave much reserve. Sorry I am metric.
Now displacement is a mysterious figure it is very hard to know what it includes. Designer like to keep it low because the lower it is the more attractive is the design. But it is not uncommon for cruisers to raise the design water line (displacement) by four inches. So unless you flood your boat you will never really know if it will float with the foam installed. To sink is a possibility that every mariner fear and for this reasons many ingenious device have been invented. Until tested no one will knows if they will work.
__________________
chala is offline   Reply With Quote
Old 20-12-2009, 06:40   #40
Long Range Cruiser
 
MarkJ's Avatar

Cruisers Forum Supporter

Join Date: Dec 2007
Location: Australian living on "Sea Life" currently in England.
Boat: Beneteau 393 "Sea Life"
Posts: 12,828
Images: 25
Shaving foam?
__________________
Notes on a Circumnavigation.
OurLifeAtSea.com

Somalia Pirates and our Convoy
MarkJ is offline   Reply With Quote
Old 20-12-2009, 08:04   #41
Registered User

Join Date: Feb 2009
Posts: 1,321
You are right MarkJ they say that ”brazilian” do not sink.
__________________
chala is offline   Reply With Quote
Old 20-12-2009, 08:06   #42
Registered User

Join Date: Aug 2009
Location: Hudson Valley N.Y.
Boat: contessa 32
Posts: 826
how about explosive keel bolts, a la NASA ,that would just drop the keel as you went down so that one would have a soggy (and sideways )life raft .BTW i am looking for employment as a navel archetect.
__________________
mrohr is offline   Reply With Quote
Old 20-12-2009, 20:34   #43
Registered User
 
boat_alexandra's Avatar

Join Date: Aug 2009
Location: chesapeake bay
Boat: bristol 27
Posts: 2,811
Quote:
Originally Posted by chala View Post
Just Googling up Bristol 27 I found displacement 6600 lbs.
6600 lbs = 2993.71 kg = 2.99371 m3 = 105.7219 cubic feet. =/- Adjustment for salt water and weight of foam this does not leave much reserve. Sorry I am metric.
Now displacement is a mysterious figure it is very hard to know what it includes. Designer like to keep it low because the lower it is the more attractive is the design. But it is not uncommon for cruisers to raise the design water line (displacement) by four inches. So unless you flood your boat you will never really know if it will float with the foam installed. To sink is a possibility that every mariner fear and for this reasons many ingenious device have been invented. Until tested no one will knows if they will work.
I am not using quite 105cu ft (more like 90-100), but fiberglass is a major component of my boat, and you only need to float 40% of the weight of the glass that is underwater. The wood in the boat also likely weighs several hundred pounds, and it provides positive flotation. Even the volume of the 2500lb balast floats something like 300lbs (so only need 2200 lbs there) I think for this reason it will probably float pretty well, but it is true that I won't know until I try. I will also start throwing heavy stuff overboard like crazy to drop another 600lbs of sinking stuff if needed. Anything onboaard that floats, I might as well keep it.

I plan to get an epirb so if the boat sinks, I will have it on an inflatable (not a proper life raft though)

I found that I can only cut the styrofoam (using stainless steel wire from my lifeline across 12v battery) to fill 80-90% of the void. It is just too hard to cut the pieces to fit perfectly especially around rounded edges. For this reason I think unfortunately I will be purchasing a small amount of 2 part pour foam to fill the gaps. Hopefully I can fill most of the space this way.

I did not want to get the pour foam because at only 50 degrees it only expands to about 50% of the 80 degree volume. It was also about
twice the expense (4 times at 50 degree weather) I think I will pour it when I get farther south. It will also give me additional flotation margin.

Thanks for all the replies
__________________
boat_alexandra is offline   Reply With Quote
Old 22-12-2009, 09:21   #44
Registered User

Join Date: Feb 2009
Posts: 1,321
Quote:
Originally Posted by geckosenator View Post

Even the volume of the 2500lb balast floats something like 300lbs (so only need 2200 lbs there)
Because this volume is submerged (below the water line) it all ready contribute to the flotation of the craft.
__________________
chala is offline   Reply With Quote
Old 22-12-2009, 10:02   #45
Registered User
 
James S's Avatar

Cruisers Forum Supporter

Join Date: May 2008
Location: Yemen & Lebanon... the sailboat is in Lebenon, the dhow is in Yemen
Boat: 1978 CT48 & 65ft Cargo Dhow
Posts: 5,816
Images: 139
Do a small test with that two part foam on the Styrofoam...it will probably melt the Styrofoam.
__________________

__________________
James
S/V Arctic Lady
I love my boat, I can't afford not to!
James S is offline   Reply With Quote
Reply

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
If You Are Going to Take a Nap, Make Sure There Is Sufficient Depth Under the Boat jean1146 The Sailor's Confessional 5 05-02-2010 05:53
What Make Is this Boat? H28Sailor Monohull Sailboats 18 27-09-2009 21:19
Cheap Way to Make Unsinkable boat_alexandra Construction, Maintenance & Refit 17 02-09-2009 19:17
Caribe RIB Unsinkable? endoftheroad Auxiliary Equipment & Dinghy 5 10-06-2009 08:54
Who said you can't make $ on selling a boat? michael201 Monohull Sailboats 16 08-05-2008 08:27



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 08:23.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.