Closed Thread
 
Thread Tools Display Modes
 
Old 03-11-2013, 04:34 PM   #221
TF Site Team
 
Larry M's Avatar
 
City: JAX, FL
Country: USA
Vessel Name: Hobo
Vessel Model: Krogen 42-120
Join Date: Nov 2008
Posts: 5,737
Quote:
...boredom and routine interspersed with moments of sheer terror...
Yup. But you know, when your half way to your destination, on watch with horizon to horizon stars and you're the only one out there, priceless.
__________________
Advertisement

Larry M is offline  
Old 03-11-2013, 06:32 PM   #222
Veteran Member
 
City: Wisconsin
Country: usa
Join Date: Feb 2013
Posts: 96
Quote:
Originally Posted by Larry M View Post
Yup. But you know, when your half way to your destination, on watch with horizon to horizon stars and you're the only one out there, priceless.
YES, and here's more like that:

Blue Horizons: Dispatches from Distant Seas; Following Seas, Sailing the Globe, Sounding a Life; both by Beth Leonard
"...if you have ever wondered what it might be like to exchange conventional comforts for an adventure not packaged with round-trip airfare, Beth Leonard has written these dispatches to you" Don Casey

Lin and Larry Pardey, Cruising in Seraffyn, Seraffyn's European Adventure, Seraffyn's Oriental Adventure
These are great books about about the pleasures of sailing the world.

Dove by Robin Lee Graham
A 16 year old sails around the world.

The Cure for Anything is Salt Water, How I threw My Life Overboard and Found Happiness at Sea by Mary South
A woman buys a trawler, takes lessons and goes.
__________________

westwinds is offline  
Old 03-11-2013, 08:44 PM   #223
Senior Member
 
City: USA
Country: USA
Join Date: Sep 2012
Posts: 267
Quote:
Originally Posted by Northern Spy View Post
I don't think anyone is doubting your intentions. Okay, maybe a few. But if you thought that the dock queen was 'the one' , it shows you need to work on your plan a bit more, but because it seemed you may have been attracted to the wrong attributes of that boat, a dream. Believe it or not, many of us here have travelled and have gone to sea. We get it.

I'll leave you with a saying I had to memorize when I was a cadet. 'The sea is selective. Slow in recognizing effort and aptitude, but fast in sinking the unfit.'
I thought the Sopressa was the one until I learned more and then I knew that she wasn't. I am not the one who mentioned Sopressa. Others here have been pushing her and I said that I did not believe that she was built for passagemaking and challenged them to show me that she was blue water worthy. I stopped considering Sopressa about 6 months ago. I have been focusing more on steel boats that I know were built and able to cross safely.
GalaxyGirl is offline  
Old 03-11-2013, 09:02 PM   #224
Senior Member
 
City: USA
Country: USA
Join Date: Sep 2012
Posts: 267
Quote:
Originally Posted by Art View Post
GG

Care to share examples? - Many on TF, me included, are always anxious to learn about adventures! Feel free to expound!!
Art,
As much as I would love to share, if I did, I would completely reveal my identity. My life has been quite distinctive, in that anyone who knows me, would immediately know that it's me if I shared. Also, the general lurking public would also know exactly who I am by googling. I havn't told anyone about my latest plan, which is the boat. I love the element of surprise and the grand unveiling. But I promise, if we one day cross pathes somewhere, we can share stories over tea at sea
GalaxyGirl is offline  
Old 03-11-2013, 09:15 PM   #225
Senior Member
 
City: USA
Country: USA
Join Date: Sep 2012
Posts: 267
Quote:
Originally Posted by portager View Post
Crunching some numbers on Sopressa; using an equation I obtained from David Gerr's "Messing About In Boats" with 59' length at waterline (LWL), 87,000 lbs displacement, 18' beam, I calculate a power requirement at 10 knots of 157.6 HP with no allowance for waves or wind, which would give a fuel burn rate of 8.67 gal/hr. Using the reported 2,700 gallon fuel capacity and holding 30% reserve she could do 2,178 NMi +/- 10% in ideal conditions. However, most ships this size will be running their generator to power the ships systems, which for Sopressa means running one of the two 25 KW Westerbeke generators, which burn 2.92 gal/hr at full load. Assuming 20% average loading on the generator, fuel burn at 10 knots increases to 9.25 gal/hr and range with 30% reserve decreases to 2,040 NMI. This would be sufficient to cross the Atlantic and technically sufficient to cross the Pacific at 10 knots. The distance from Hilo HI to San Francisco CA is 2019 NMi, but most people refuel in Honolulu, HI and cross to Los Angeles, CA which is 2,233 NMI. To cross from Honolulu to LA the Sopressa would need to slow to 9.5 knots. This would require 235.1 hours or 9 days, 19 hours and 9 minutes +/- a day or two. Note: these calculations are entirely theoretical and the fuel burn rates should be confirmed with operational data. Your mileage may vary based on the actual loading of the ship, the condition of the engines, the fouling of her bottom, ...

Having said that, I would not cross Oceans in the Sopressa. She has no stabilization, either active or passive. I would prefer active stabilization with passive as a backup, but one or the other is mandatory for me. Trawlers roll and can make for a miserable trip without stabilization. All of Bebe's "Passagemakers" had stabilization. She also has a rather low D/L of 189 (see Choosing a Passagemaker ). If I remember correctly, Bebe recommend a D/L of greater than 250. The handholds in the saloon are a concern, especially with children aboard. For adults you could add handholds on the ceiling, but what do the children hold onto? On the other hand, the intelligent way to cross Oceans is to leave the children home and fly them across once the boat gets there.

Finally, I think the wide body layout of the Sopressa is far less desirable than the conventional layout. I'd prefer to have the side decks for easier docking and line handling and having the side windows less exposed to waves when she rolls.

GG: not trying to give you a hard time, plenty of others are doing that, I'm only trying to further your education. Feel free to ask questions. The only stupid question is the one you never ask.
Thanks for the info. Most of my kids are actually teens and pre-teens, so ceiling handhelds would probably work. I am really not considering the Sopressa, but the education in regard to a real life boat is great. Thank you. Would you mind elaborating a bit on the difference between passive and active stabilization. I suspect that I know the difference already, but want to see if I am correct.
GalaxyGirl is offline  
Old 03-11-2013, 09:16 PM   #226
Senior Member
 
City: USA
Country: USA
Join Date: Sep 2012
Posts: 267
Quote:
Originally Posted by Larry M View Post
Yup. But you know, when your half way to your destination, on watch with horizon to horizon stars and you're the only one out there, priceless.
Good answer.
GalaxyGirl is offline  
Old 03-11-2013, 09:30 PM   #227
Scraping Paint
 
City: -
Country: -
Join Date: Oct 2007
Posts: 13,748
Passive stabilizers are mechanical devices, usually "birds" or "fish" that are hung down into the water from heavily constructed outriggers that hinge out from the side of the boat. Much like the trolling poles on a salmon troller.

The "birds" are finned weights that are suspended a few feet below the surface and "swim" alongside the boat. Because of their shape, they resist the rolling movement of the boat. They are passive because they don't do anything other than hang down from the outriggers.

Active stabilizers are just that. They are usually in the form of powered fins attached to the bottom of the boat. Electrically or hydraulically driven, they (usually) have a gyro mechanism that senses the boat's rolling and pitching movement and this information in turn directs the fins to move to counteract it. So if the boat rolls to the left the fins will move to counter the roll.

Active stabilizer systems are used on boats as small as a Grand Banks 42 up to vessels as large as a 1000' cruise ship.

The advantage of passive stabilizers is they are very simple. No motors or computers or gyro sensors, etc. The advantage of active stabilizers is they actively and rapidly counter the movement of the boat and so tend to provide a smoother ride than passive stabilizers.

The disadvantage of passive stabilizers is they require a properly designed, heavy-duty structure to support them and take the high strain of resistance from the birds in the water. The disadvantage of active stabilizers is the cost, the complexity of the system, their vulnerability to being hit by debris in the water or obstructions in shallow water, and the added service and maintenance requirements imposed on the boat owner.

The first photo below shows a pair of stabilizer "birds" on the Nordhavn across from our slip in Bellingham. The second photo is of the same boat showing the heavy outriggers or stabilizer poles that are hinged outboard and suspend the heavy birds in the water.

Click image for larger version

Name:	image-425004438.jpg
Views:	120
Size:	53.9 KB
ID:	17114



Click image for larger version

Name:	image-1506466626.jpg
Views:	110
Size:	57.3 KB
ID:	17115
Marin is offline  
Old 03-11-2013, 11:34 PM   #228
Veteran Member
 
City: Wisconsin
Country: usa
Join Date: Feb 2013
Posts: 96
Marin has a good explanation. Stabalizers must be important because Voyaging Under Power, fourth edition, has a whole 23 page chapter called Stabilizing Against Rolling. There are also sails used for steadying a trawler mentioned in the book.
westwinds is offline  
Old 03-11-2013, 11:47 PM   #229
Scraping Paint
 
City: -
Country: -
Join Date: Oct 2007
Posts: 13,748
Going on what people who have GBs and steady sails have told me, the sails do a great job of keeping a boat heading into the wind (and presumably the waves) when on a mooring or at anchor. This greatly reduces the yawing back and forth and the subsequent uncomfortable rolling motion added to the pitching motion. The steady sail is sort of like putting bigger feathers on the back of an arrow, and in this respect they can be worthwhile, although we accomplish the same thing with a stern anchor.

However they have all said that a steady sail of the size that can be carried on GBs and similar boats have little to no effect in reducing roll underway in a quartering or beam sea. The sails are simply not large enough to make any significant difference.

So if roll reduction underway is something one wants to do, passive or active stabilizers are the way to do it unless one can carry a very large steady sail on one's cruiser, with the mast, mast stay, and hardware strength to take the tremendous pressure.
Marin is offline  
Old 03-12-2013, 12:39 AM   #230
Art
Guru
 
Art's Avatar
 
City: SF Bay Area
Country: USA
Vessel Model: Tollycraft 34' Tri Cabin
Join Date: Feb 2011
Posts: 7,979
For three years I helped dad design, build, and sea test this stabilizer. Simple, effective, affordable - flexable main body, no other moving parts!
_______________________________________________
United States Patent / 3,753,415 / August 21, 1973

HYDROFOIL-SHAPED STABILIZING OR ATTITUDE-AFFECTING MEANS FOR BOATS

Abstract

A hydrofoil-shaped stabilizer or attitude-changing means for boats, having an elongated frame assembly adapted to be connected to a submerged portion of the hull of a boat with its longitudinal axis parallel to the fore-to-aft axis of the boat. A flexible curtain assembly extends about the frame assembly and is fixed thereto but free to move laterally and to a more limited extent longitudinally relative to the frame assembly. The interior of the curtain assembly communicates with the surrounding water and is deflected to one side or the other relative to the frame assembly by its displacement relative to the water caused by a change in the attitude of the boat so as to form a hydrofoil having a camber for generating forces to oppose the change in attitude to one side or the other when the boat is underway.
Art is offline  
Old 03-12-2013, 01:16 AM   #231
Senior Member
 
portager's Avatar
 
City: Silverado, CA
Country: USA
Vessel Name: Osprey
Vessel Model: Nimble Wanderer
Join Date: May 2011
Posts: 173
Marin provided a good description except that the active fins are mounted on either side about half way between the keel and the waterline and near the center fore and aft. The active stabilizers are fin shaped and when they are tilted relative to the flow they produce a positive or negative lift force, like a small wing, to counter roll. A gyro is used to sense roll and a control system deflects the fins to produce the desired force to counter roll. Most active stabilizers claim to reduce roll by up to 80% to 90%. Passive stabilizers might reduce roll about 50%.

It used to be that active roll stabilizers required flow over them so they only worked while underway. However, modern stabilizers have the fins mounted off center so they can produce some force, like a paddle even with no flow, so the work at anchor (although I don't know how effective they are). The down side of active stabilization at anchor is you need to run the generator.
portager is offline  
Old 03-12-2013, 03:40 AM   #232
TF Site Team
 
Peter B's Avatar
 
City: Brisbane
Country: Australia
Vessel Name: Lotus
Vessel Model: Clipper (CHB) 34 Sedan/Europa style
Join Date: Jun 2008
Posts: 6,669
Send a message via Skype™ to Peter B
If I had a boat that was ocean capable, and the money to afford to equipe it properly, I would now go for a form of active stabilisation the above did not mention, and that is the full gyroscopic stabilisers which are fitted internally, and stabilse by rotating at high speed in a vacuum. They do draw power, as do all active stabilsers, but that is something one is not usualy short of when ocean crossing is the game, via engines or generators. This type has two added advantages of definitely working at anchor, (if required), and they are not vulnerable to damage in such as a grounding, nor the danger of snagging something in the water like the passive fish type. Have a look here....



Seakeeper Website
Peter B is offline  
Old 03-12-2013, 09:33 AM   #233
Senior Member
 
portager's Avatar
 
City: Silverado, CA
Country: USA
Vessel Name: Osprey
Vessel Model: Nimble Wanderer
Join Date: May 2011
Posts: 173
Peter B has a good point. The Seakeeper gyro stabilization is another option and could be a much easier retrofit than active or passive roll stabilization since they don't require through hulls or stick out of the boat. Their smallest unit requires about 1x1x0.7 meters of room, 2.24 KW of power and a very solid mount so they may require structural modifications to the boat. They also require about 35 minutes to reach their 7,500 rpm operating speed. I haven't found a good comparison of gyro stabilization to active stabilization, so I'm not sure which is more effective underway. However, gyro stabilization should be more effective at anchor since its performance isn't dependent on speed.
portager is offline  
Old 03-12-2013, 09:46 AM   #234
Guru
 
City: Carefree, Arizona
Country: usa
Vessel Name: sunchaser V
Vessel Model: DeFever 48
Join Date: Apr 2008
Posts: 6,369
Quote:
Originally Posted by portager View Post
gyro stabilization should be more effective at anchor since its performance isn't dependent on speed.
FF needs one of these so he could run his noise maker at anchor
sunchaser is offline  
Old 03-12-2013, 09:52 AM   #235
Guru
 
City: Carefree, Arizona
Country: usa
Vessel Name: sunchaser V
Vessel Model: DeFever 48
Join Date: Apr 2008
Posts: 6,369
Quote:
Originally Posted by GalaxyGirl View Post
Art,
I would completely reveal my identity. My life has been quite distinctive, in that anyone who knows me, would immediately know that it's me if I shared. Also, the general lurking public would also know exactly who I am by googling.
The nice thing about boating is there are some truly famous people on the water who are accepted for their skills, savvy and are a bit humble about it all.
sunchaser is offline  
Old 03-12-2013, 11:46 AM   #236
Guru
 
Codger2's Avatar
 
City: San Diego
Country: US
Vessel Name: "Sandpiper"
Vessel Model: 2006 42' Ocean Alexander Sedan
Join Date: Oct 2007
Posts: 5,420
Quote:
Originally Posted by GalaxyGirl View Post
As much as I would love to share, if I did, I would completely reveal my identity. My life has been quite distinctive, in that anyone who knows me, would immediately know that it's me if I shared.
That's ironic as I have the same potential problem! Only three TF members know my true identity (dwhatty, FlyWright & moonstruck) and they are sworn to secrecy. (We all belong to the same institution.)
__________________
Codger2

My passion for improving my boat(s) exceeds my desire to constantly cruise them.
Codger2 is offline  
Old 03-12-2013, 11:56 AM   #237
Senior Member
 
mahal's Avatar
 
Join Date: May 2010
Posts: 436
Quote:
Originally Posted by GalaxyGirl View Post
Art,
As much as I would love to share, if I did, I would completely reveal my identity. My life has been quite distinctive, in that anyone who knows me, would immediately know that it's me if I shared. Also, the general lurking public would also know exactly who I am by googling. I havn't told anyone about my latest plan, which is the boat. I love the element of surprise and the grand unveiling. But I promise, if we one day cross pathes somewhere, we can share stories over tea at sea
And these people that know you, don't know what your mom looks like? Just in case you forgot, her avatar is a picture of herself.
mahal is offline  
Old 03-12-2013, 12:11 PM   #238
Senior Member
 
portager's Avatar
 
City: Silverado, CA
Country: USA
Vessel Name: Osprey
Vessel Model: Nimble Wanderer
Join Date: May 2011
Posts: 173
Quote:
Originally Posted by mahal View Post
And these people that know you, don't know what your mom looks like? Just in case you forgot, her avatar is a picture of herself.
How do you know that her Mom's avatar is a picture of herself?
portager is offline  
Old 03-12-2013, 12:20 PM   #239
Guru
 
Join Date: Oct 2007
Posts: 734
GALAXY GIRL
Chrisjs is offline  
Old 03-12-2013, 12:30 PM   #240
Guru
 
Phil Fill's Avatar
 
City: Everett Wa
Country: US
Vessel Name: Eagle
Vessel Model: Roughwater 58 pilot house
Join Date: Oct 2007
Posts: 2,919

It time this discussion be closed and several new one started? We are way off topic and not even talking/looking at wood boats?
__________________

Phil Fill is offline  
Closed Thread

Thread Tools
Display Modes

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





All times are GMT -5. The time now is 05:59 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012