Cruisers Forum
 


Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 15-09-2013, 21:28   #1
Registered User
 
Incentive's Avatar

Join Date: Jul 2013
Posts: 73
Tonnage?

Who gives it? How is it calculated?

When I obtained my folkboat this plate was on bulkhead, 3.91tonnes is about 7820lbs how is this possible when this boat is supposed to weigh 5000lbs?

Click image for larger version

Name:	image-90535429.jpg
Views:	236
Size:	140.8 KB
ID:	67258
Incentive is offline   Reply With Quote
Old 15-09-2013, 21:53   #2
Registered User
 
Dennis.G's Avatar

Join Date: May 2011
Location: Sea of Cortez and the U.P. of Michigan
Boat: Celestial 48
Posts: 904
Re: Tonnage?

My boat has a specified displacement of 13.5 tons, but weighs 19 tons.

I have a lot of stuff on board, but can't see it all being close to 11,000 lbs.

Full fuel and water tanks (big tanks) would count for 3,500 lbs however.

Don't know how the rated tonnage is calculated.
Dennis.G is offline   Reply With Quote
Old 15-09-2013, 21:53   #3
Registered User

Join Date: Oct 2011
Posts: 2,687
Re: Tonnage?

Tonnage as it is in the marine use, is a measure of volume, not weight. It (I believe) was originally the volume of the cargo hold of vessels. It is now the volume of the enclosed space on a vessel, other than machinery spaces. Your Folkboat is not overweight. By the way, I think folkboats are great. There have been several long voyages by CF members in them. I believe one was west coast to Hawaii, and another from Washington to Mexico. I am sure there are many other tales of how good the design is. ______Good Luck ______Grant.
gjordan is offline   Reply With Quote
Old 15-09-2013, 22:01   #4
Marine Service Provider
 
peghall's Avatar

Join Date: Feb 2011
Posts: 3,019
Re: Tonnage?

Tonnage has nothing to do with the weight of your boat. It is a measure of how much wine a vessel can carry.

The word "tun" was originally a size of a cask used to ship wine from Spain & Portugal to England. In 1347 a tax of 3 shillings per tun was imposed and this was called "tonnage." A ship's size became known by the number of casks it could carry, and the word tonnage started being used to describe a ship's size.

It was found that if you took the length x the breadth x the depth of the hold under the deck and divided by 100 it was close to the number of casks. That is where we get the "Measurement ton" of 100 cubic feet per ton.

There are several kinds of tonnage: The first two are used by the tax collector. The next two are used by designers. The fifth and sixth are used by freight salesmen and canal operators and the last one is used by the USCG for documenting boats.

Gross Tonnage - is the internal volume in cubic feet of the vessel minus certain spaces above the main or "tonnage" deck, like stacks and ventilators, which are called "exemptions" .

Net Registered Tonnage - is obtained by deducting from the gross tonnage the volume of space that can't be used for paying cargo or passengers, that is to say the space occupied by the engines, the crew's quarter, the stores, etc.

Displacement Tonnage - is the actual weight of the water "displaced" by the ship and is usually quoted in long tons of 2240 lbs.

Light Displacement Tonnage - is the weight with nothing in it.

Loaded Displacement Tonnage - is the fully loaded weight to the maximum and is on her summer draft in salt water.

Deadweight Tonnage - is the difference between Light and Loaded

Displacement Tonnage....the actual carrying capacity of the vessel.

Panama & Suez Canal Tonnages - these are different from the internationally accepted definitions. There used to be a lot of variations between countries and the canal owners thought they were being conned, so they came up with their own definitions.

Simplified Measurement System - The USCG decided that all this was way too much for bureaucrats to deal with for yachts, so they came up with their own formula:

Take the horizontal distance between the outboard ends of the boat, not including rudders and bow sprits. Multiply that by the maximum beam outside to outside. Multiply that by the distance from the sheer line not including bulwarks or cap rails to the outside bottom of the hull not including the keel. Add the volume of the deck house/cabin top. Multiply by .5 for sailboats and .67 for power boats. Divide by 100. This will give you the "Gross Tonnage." Net tonnage is 90% of gross for sailboats and 80% for power boats.

It should now be obvious to anyone who's managed to get this far that your boat's "tonnage" no longer has anything to do with anything real; it only exists in the mind of some government bureaucrat.

Another bit of trivia...
Rummage was the manner in which the wine casks were stored in the hold of the ship and came to refer to the whole ship's cargo. after a voyage any unclaimed and damaged cargo was stacked on the dock beside the boat and offered for sale - a rummage sale. another word of French maritime origin.
__________________
© 2024 Peggie Hall
Specializing in marine sanitation since '87.
Author "The NEW Get Rid of Boat Odors"
peghall is offline   Reply With Quote
Old 15-09-2013, 22:07   #5
Registered User
 
Incentive's Avatar

Join Date: Jul 2013
Posts: 73
Quote:
Originally Posted by peghall View Post
Tonnage has nothing to do with the weight of your boat. It is a measure
of how much wine a vessel can carry.

The word "tun" was originally a size of a cask used to ship wine from Spain & Portugal to England. In 1347 a tax of 3 shillings per tun was imposed and this was called "tonnage." A ship's size became known by the number of casks it could carry, and the word tonnage started being used to describe a ship's size.

It was found that if you took the length x the breadth x the depth of the hold under the deck and divided by 100 it was close to the number of casks. That is where we get the "Measurement ton" of 100 cubic feet per
ton.

There are several kinds of tonnage: The first two are used by the tax collector. The next two are used by designers. The fifth and sixth are used by freight salesmen and canal operators and the last one is used by the USCG for documenting boats.

Gross Tonnage - is the internal volume in cubic feet of the vessel minus certain spaces above the main or "tonnage" deck, like stacks and ventilators, which are called "exemptions" .

Net Registered Tonnage - is obtained by deducting from the gross tonnage the volume of space that can't be used for paying cargo or passengers, that is to say the space occupied by the engines, the crew's quarter, the stores, etc.

Displacement Tonnage - is the actual weight of the water "displaced" by the ship and is usually quoted in long tons of 2240 lbs.

Light Displacement Tonnage - is the weight with nothing in it.

Loaded Displacement Tonnage - is the fully loaded weight to the maximum and is on her summer draft in salt water.

Deadweight Tonnage - is the difference between Light and Loaded

Displacement Tonnage....the actual carrying capacity of the vessel.

Panama & Suez Canal Tonnages - these are different from the internationally accepted definitions. There used to be a lot of variations between countries and the canal owners thought they were being conned, so they came up with their own definitions.

Simplified Measurement System - The USCG decided that all this was way too much for bureaucrats to deal with for yachts so they came up with
their own formula:

Take the horizontal distance between the outboard ends of the boat not
including rudders and bow sprits. Multiply that by the maximum beam outside to outside. Multiply that by the distance from the sheer line not including bulwarks or cap rails to the outside bottom of the hull not including the keel.
Add the volume of the deck house/cabin top. Multiply by .5 for sailboats and .67 for power boats. Divide by 100.

This will give you the "Gross Tonnage". Net tonnage is 90% of gross for
sailboats and 80% for power boats.

It should be obvious to anyone who's managed to get this far that your boat's "tonnage" no longer has anything to do with anything real; it only exists in the mind of some government bureaucrat.

Another bit of trivia...
Rummage was the manner in which the wine casks were stored in the hold of the ship and came to refer to the whole ship's cargo. after a voyage any unclaimed and damaged cargo was stacked on the dock beside the boat and offered for sale - a rummage sale. another word of French maritime
origin.
Wow that's as far out as I could have ever expected an answer !!!!
Wasn't expecting this....Thank you Lady
Incentive is offline   Reply With Quote
Old 15-09-2013, 22:08   #6
Registered User
 
DDabs's Avatar

Join Date: Aug 2011
Location: St. Petersburg, FL
Boat: Morgan Moorings 50
Posts: 1,895
Images: 27
Re: Tonnage?

cool stuff peg
DDabs is offline   Reply With Quote
Old 15-09-2013, 22:21   #7
Registered User
 
deckofficer's Avatar

Join Date: Feb 2011
Location: Northern and Southern California
Boat: too many
Posts: 3,731
Images: 4
Re: Tonnage?

Quote:
Originally Posted by peghall View Post
Tonnage has nothing to do with the weight of your boat. It is a measure of how much wine a vessel can carry.

The word "tun" was originally a size of a cask used to ship wine from Spain & Portugal to England. In 1347 a tax of 3 shillings per tun was imposed and this was called "tonnage." A ship's size became known by the number of casks it could carry, and the word tonnage started being used to describe a ship's size.

It was found that if you took the length x the breadth x the depth of the hold under the deck and divided by 100 it was close to the number of casks. That is where we get the "Measurement ton" of 100 cubic feet per ton.

There are several kinds of tonnage: The first two are used by the tax collector. The next two are used by designers. The fifth and sixth are used by freight salesmen and canal operators and the last one is used by the USCG for documenting boats.

Gross Tonnage - is the internal volume in cubic feet of the vessel minus certain spaces above the main or "tonnage" deck, like stacks and ventilators, which are called "exemptions" .

Net Registered Tonnage - is obtained by deducting from the gross tonnage the volume of space that can't be used for paying cargo or passengers, that is to say the space occupied by the engines, the crew's quarter, the stores, etc.

Displacement Tonnage - is the actual weight of the water "displaced" by the ship and is usually quoted in long tons of 2240 lbs.

Light Displacement Tonnage - is the weight with nothing in it.

Loaded Displacement Tonnage - is the fully loaded weight to the maximum and is on her summer draft in salt water.

Deadweight Tonnage - is the difference between Light and Loaded

Displacement Tonnage....the actual carrying capacity of the vessel.

Panama & Suez Canal Tonnages - these are different from the internationally accepted definitions. There used to be a lot of variations between countries and the canal owners thought they were being conned, so they came up with their own definitions.

Simplified Measurement System - The USCG decided that all this was way too much for bureaucrats to deal with for yachts, so they came up with their own formula:

Take the horizontal distance between the outboard ends of the boat, not including rudders and bow sprits. Multiply that by the maximum beam outside to outside. Multiply that by the distance from the sheer line not including bulwarks or cap rails to the outside bottom of the hull not including the keel. Add the volume of the deck house/cabin top. Multiply by .5 for sailboats and .67 for power boats. Divide by 100. This will give you the "Gross Tonnage." Net tonnage is 90% of gross for sailboats and 80% for power boats.

It should now be obvious to anyone who's managed to get this far that your boat's "tonnage" no longer has anything to do with anything real; it only exists in the mind of some government bureaucrat.

Another bit of trivia...
Rummage was the manner in which the wine casks were stored in the hold of the ship and came to refer to the whole ship's cargo. after a voyage any unclaimed and damaged cargo was stacked on the dock beside the boat and offered for sale - a rummage sale. another word of French maritime origin.
I felt like I was back at the academy.
__________________
Bob
USCG Unlimited Tonnage Open Ocean (CMA)
https://tbuckets.lefora.com/
deckofficer is offline   Reply With Quote
Old 15-09-2013, 22:22   #8
Marine Service Provider
 
peghall's Avatar

Join Date: Feb 2011
Posts: 3,019
Re: Tonnage?

Thanks. Honesty compels me to confess that I'm not the author...a guy named Glenn Ashmore posted on a forum (can't remember where) more than 10 years ago...I loved it and saved it.
__________________
© 2024 Peggie Hall
Specializing in marine sanitation since '87.
Author "The NEW Get Rid of Boat Odors"
peghall is offline   Reply With Quote
Old 17-09-2013, 12:34   #9
Registered User

Join Date: Apr 2012
Location: Currently in the Caribbean
Boat: Cheoy Lee 47 CC
Posts: 1,028
Re: Tonnage?

Funny the origin of terms in the English language and how many commonly used terms are derived from maritime origins. It's always interesting to see the history.
lifeofreilly57 is offline   Reply With Quote
Old 17-09-2013, 13:13   #10
Moderator Emeritus
 
David M's Avatar

Cruisers Forum Supporter

Join Date: Sep 2007
Location: Eastern Tennessee
Boat: Research vessel for a university, retired now.
Posts: 10,406
Re: Tonnage?

Quote:
Originally Posted by peghall View Post
Tonnage has nothing to do with the weight of your boat. It is a measure of how much wine a vessel can carry.

The word "tun" was originally a size of a cask used to ship wine from Spain & Portugal to England. In 1347 a tax of 3 shillings per tun was imposed and this was called "tonnage." A ship's size became known by the number of casks it could carry, and the word tonnage started being used to describe a ship's size.

It was found that if you took the length x the breadth x the depth of the hold under the deck and divided by 100 it was close to the number of casks. That is where we get the "Measurement ton" of 100 cubic feet per ton.

There are several kinds of tonnage: The first two are used by the tax collector. The next two are used by designers. The fifth and sixth are used by freight salesmen and canal operators and the last one is used by the USCG for documenting boats.

Gross Tonnage - is the internal volume in cubic feet of the vessel minus certain spaces above the main or "tonnage" deck, like stacks and ventilators, which are called "exemptions" .

Net Registered Tonnage - is obtained by deducting from the gross tonnage the volume of space that can't be used for paying cargo or passengers, that is to say the space occupied by the engines, the crew's quarter, the stores, etc.

Displacement Tonnage - is the actual weight of the water "displaced" by the ship and is usually quoted in long tons of 2240 lbs.

Light Displacement Tonnage - is the weight with nothing in it.

Loaded Displacement Tonnage - is the fully loaded weight to the maximum and is on her summer draft in salt water.

Deadweight Tonnage - is the difference between Light and Loaded

Displacement Tonnage....the actual carrying capacity of the vessel.

Panama & Suez Canal Tonnages - these are different from the internationally accepted definitions. There used to be a lot of variations between countries and the canal owners thought they were being conned, so they came up with their own definitions.

Simplified Measurement System - The USCG decided that all this was way too much for bureaucrats to deal with for yachts, so they came up with their own formula:

Take the horizontal distance between the outboard ends of the boat, not including rudders and bow sprits. Multiply that by the maximum beam outside to outside. Multiply that by the distance from the sheer line not including bulwarks or cap rails to the outside bottom of the hull not including the keel. Add the volume of the deck house/cabin top. Multiply by .5 for sailboats and .67 for power boats. Divide by 100. This will give you the "Gross Tonnage." Net tonnage is 90% of gross for sailboats and 80% for power boats.

It should now be obvious to anyone who's managed to get this far that your boat's "tonnage" no longer has anything to do with anything real; it only exists in the mind of some government bureaucrat.

Another bit of trivia...
Rummage was the manner in which the wine casks were stored in the hold of the ship and came to refer to the whole ship's cargo. after a voyage any unclaimed and damaged cargo was stacked on the dock beside the boat and offered for sale - a rummage sale. another word of French maritime origin.
Excellent post!
__________________
David

Life begins where land ends.
David M is offline   Reply With Quote
Old 17-09-2013, 13:15   #11
Moderator Emeritus
 
David M's Avatar

Cruisers Forum Supporter

Join Date: Sep 2007
Location: Eastern Tennessee
Boat: Research vessel for a university, retired now.
Posts: 10,406
Re: Tonnage?

Quote:
Originally Posted by deckofficer View Post
I felt like I was back at the academy.
Same here.
__________________
David

Life begins where land ends.
David M is offline   Reply With Quote
Old 17-09-2013, 13:29   #12
Senior Cruiser
 
boatman61's Avatar

Community Sponsor
Cruisers Forum Supporter

Join Date: Jan 2010
Location: PORTUGAL
Posts: 30,638
Images: 2
pirate Re: Tonnage?

Good one Peg..
__________________


You can't beat a people up (for 75yrs+) and have them say..
"I Love You.. ". Murray Roman.
Yet the 'useful idiots' of the West still dance to the beat of the apartheid drums.
boatman61 is online now   Reply With Quote
Old 17-09-2013, 13:54   #13
Registered User
 
Badsanta's Avatar

Join Date: Oct 2007
Location: virginia
Boat: islandpacket
Posts: 1,967
Do you guys have to quote the entire post. I think we get it.
And thanks Peg
__________________
That derelict boat was another dream for somebody else, don't let it be your nightmare and a waste of your life.
Badsanta is offline   Reply With Quote
Old 17-09-2013, 16:13   #14
Moderator
 
Jim Cate's Avatar

Join Date: May 2008
Location: cruising SW Pacific
Boat: Jon Sayer 1-off 46 ft fract rig sloop strip plank in W Red Cedar
Posts: 21,198
Re: Tonnage?

Yes, her post once again shows that she's not just a pretty face... first toilets, now tuns!

Thanks Peggy

Jim
__________________
Jim and Ann s/v Insatiable II, lying Port Cygnet Tasmania once again.
Jim Cate is offline   Reply With Quote
Old 17-09-2013, 16:35   #15
Registered User
 
FSMike's Avatar

Join Date: Aug 2009
Location: Bahamas/Florida
Boat: Solaris Sunstar 36' catamaran
Posts: 2,686
Images: 5
Re: Tonnage?

Learn something new every day. I always thought it was grain, not wine.
Now if you ferment the grain --- lol
Thanks Peg.
__________________
Sail Fast Live Slow
FSMike is offline   Reply With Quote
Reply


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


Advertise Here


All times are GMT -7. The time now is 10:28.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.