Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 27-08-2008, 08:31   #1
Eternal Member
 
imagine2frolic's Avatar

Join Date: Feb 2008
Location: Las Brisas Panama AGAIN!
Boat: Simpson, Catamaran, 46ft. IMAGINE
Posts: 4,508
Images: 123
WHERE DO I MEASURE?

When I measure my beam in the hulls. Do I measure at the waterline, or the beamiest part of the hull? It makes a huge difference in ratio.
__________________

__________________
imagine2frolic is offline   Reply With Quote
Old 27-08-2008, 08:42   #2
Registered User
 
Tnflakbait's Avatar

Join Date: Apr 2006
Location: Southern California
Boat: CSK, 33' Aita Pe'ape'a
Posts: 338
Images: 7
If you are looking for a length/beam ratio then I would say at the waterline.
__________________

__________________
Tnflakbait is offline   Reply With Quote
Old 27-08-2008, 08:43   #3
Registered User

Join Date: Jan 2007
Location: Fremantle Australia
Boat: Schioning 12.3 "Wilderness" Bi-Rig under construction
Posts: 558
Send a message via Skype™ to Whimsical
If it aint in the water it has no effect so measure it at the waterline

Mike
__________________
Whimsical is offline   Reply With Quote
Old 27-08-2008, 08:44   #4
Eternal Member
 
imagine2frolic's Avatar

Join Date: Feb 2008
Location: Las Brisas Panama AGAIN!
Boat: Simpson, Catamaran, 46ft. IMAGINE
Posts: 4,508
Images: 123
That was my logical guess. I was pulling watertanks out last night from the bilge, and the question just came to me....THANKS
__________________
imagine2frolic is offline   Reply With Quote
Old 27-08-2008, 09:20   #5
Registered User

Join Date: Jun 2007
Location: kefalonia ,ionian islands
Boat: Solaris Sunstar 38, Wild Honey
Posts: 149
Images: 1
Quote:
Originally Posted by imagine2frolic View Post
When I measure my beam in the hulls. Do I measure at the waterline, or the beamiest part of the hull? It makes a huge difference in ratio.
ok i agree its a waterline measurement but its taken at the widest point of the hull then, its not a constant width throughout the length so how can it be a representative measurement ??
__________________
gramos is offline   Reply With Quote
Old 27-08-2008, 09:35   #6
Moderator Emeritus
 
GordMay's Avatar

Join Date: Mar 2003
Location: Thunder Bay, Ontario - 48-29N x 89-20W
Boat: (Cruiser Living On Dirt)
Posts: 31,596
Images: 240
Generally, the beam is the widest part of the hull, measured at a right angle to the length of the boat, no matter where it occurs (vertically).
__________________
Gord May
"If you didn't have the time or money to do it right in the first place, when will you get the time/$ to fix it?"



GordMay is offline   Reply With Quote
Old 27-08-2008, 09:46   #7
Eternal Member
 
imagine2frolic's Avatar

Join Date: Feb 2008
Location: Las Brisas Panama AGAIN!
Boat: Simpson, Catamaran, 46ft. IMAGINE
Posts: 4,508
Images: 123
I always managed to think of the beam being measured at the deck. With the waterline ratio to length on a multi seems it would be different. When I get back into the bilge tonight I will measure the width of the hull at the waterline also. I am just curious to see the difference in the ratio......14to1 as compared to 8to1 as an example
__________________
imagine2frolic is offline   Reply With Quote
Old 27-08-2008, 09:48   #8
Moderator Emeritus
 
David M's Avatar

Cruisers Forum Supporter

Join Date: Sep 2007
Location: San Francisco Bay
Boat: research vessel
Posts: 10,153
Gord is correct. When you see specifications for boats, you are seeing the measurement for the absolute widest part of the boat.

If you want to measure beam for stability reasons you have to realize that the maximum width at the waterline might change as the boat heels because as the water "sees" it, the shape of the hull changes as angle of inclination changes.
__________________
David

Life begins where land ends.
David M is online now   Reply With Quote
Old 27-08-2008, 09:55   #9
Eternal Member
 
imagine2frolic's Avatar

Join Date: Feb 2008
Location: Las Brisas Panama AGAIN!
Boat: Simpson, Catamaran, 46ft. IMAGINE
Posts: 4,508
Images: 123
David M ,
Is that different from the waterline on a cat? For ratio sake only. I understand the mono situation, but after reading all of these post about ratios on cats. I just started wondering where the measurement is taken last night while my head was below the waterline
__________________
imagine2frolic is offline   Reply With Quote
Old 27-08-2008, 10:26   #10
Registered User

Join Date: Nov 2005
Location: Ohio
Posts: 2,313
B is not the same as BWL.

If you're going to measure waterline dimensions the next question that begs to be asked is........ do you measure static or do you measure at speed? Do you measure in light ship or do you measure fully loaded? And on and on........

It's been a long time since we've measured our boats (bwl, lwl, 7% lwl offsets,...)for racing, you can change the rating substantially by how you rig and ballast a boat. Today we just say screw it and have another beer......

__________________
Joli is offline   Reply With Quote
Old 27-08-2008, 10:30   #11
Eternal Member
 
imagine2frolic's Avatar

Join Date: Feb 2008
Location: Las Brisas Panama AGAIN!
Boat: Simpson, Catamaran, 46ft. IMAGINE
Posts: 4,508
Images: 123
Joli,

Nice friends you have there.....LOLOLOLOLOL
__________________
imagine2frolic is offline   Reply With Quote
Old 27-08-2008, 10:36   #12
Registered User

Join Date: Nov 2005
Location: Ohio
Posts: 2,313
I just gotta make it to Octoberfest some day, beer and boobs

Sorry about the hijack, returning now to your regularly scheduled programing.

__________________
Joli is offline   Reply With Quote
Old 27-08-2008, 15:03   #13
Senior Cruiser
 
44'cruisingcat's Avatar

Cruisers Forum Supporter

Join Date: Sep 2006
Posts: 7,459
Images: 69
I though one of them WAS you Joli!

If you're measuring for the LWL/BWL ratio then measure both length and beam at the designed waterline. If you measure LOA vs BOA on a cat you get some pretty slow sounding ratios.
__________________
44'cruisingcat is offline   Reply With Quote
Old 27-08-2008, 15:34   #14
Eternal Member
 
imagine2frolic's Avatar

Join Date: Feb 2008
Location: Las Brisas Panama AGAIN!
Boat: Simpson, Catamaran, 46ft. IMAGINE
Posts: 4,508
Images: 123
44,

That was my thinking. That will teach me to get my head down in the bilge to work.........lolololololol....I'll send the wife next time
__________________
imagine2frolic is offline   Reply With Quote
Old 27-08-2008, 17:57   #15
Moderator Emeritus
 
Ex-Calif's Avatar

Cruisers Forum Supporter

Join Date: May 2007
Location: Singapore
Boat: Maxi 77 - Relax Lah!
Posts: 11,514
Images: 4
Quote:
Originally Posted by Joli View Post

It's been a long time since we've measured our boats (bwl, lwl, 7% lwl offsets,...)for racing, you can change the rating substantially by how you rig and ballast a boat. Today we just say screw it and have another beer......
I was gonna ask where she was gonna put all that freakin' beer.

Then I figured it out...
__________________

__________________
Relax Lah! is For Sale <--- Click
Click--> Custom CF Google Search or CF Rules
You're gonna need a bigger boat... - Martin Brody
Ex-Calif 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
How to Measure the Gloss of the Textured Gelcoat Surface roggy Construction, Maintenance & Refit 11 30-07-2010 16:53
How to measure the size of jib hanks phorvati Deck hardware: Rigging, Sails & Hoisting 3 12-11-2006 10:09
How to Measure Complex Curves? ssullivan Construction, Maintenance & Refit 6 07-02-2006 08:35



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 09:59.


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.