What is a Ton in Boat Weight

[toerail]

Ok
What is the weight of your boat
I see it used in both long tons and short tons
My boat is recorded on the documentation as 13 tons,

but thats 26,000 lbs, is that wrong
Did you use long or short tons on the documentation?
A documentation person did that for me decades ago

Then an article turns around and says my keel is 9 tons alone
Well that is short tons
Some big boats have recorded weights in tons that are
a few tons more than my keel weight
Is that correct?
I'm getting confused

[tkeithlu]

A short ton is 2,000 pounds
A long ton is 1,000 kilograms, or about 2,200 pounds.

You have a monohull with substantial ballast. I'm still impressed that it's 18,000 pounds in a 41 ft boat. That seems high, but it's been awhile since I sailed a 40' Rhodes with 6,000 pounds of ballast. Maybe design has changed.

OK, but which was being used when someone says "tons?" Are they otherwise talking American, as in feet, or are they talking like the civilized world, as in meters?

[Orion Jim]

Originally Posted by toerail

Ok
What is the weight of your boat
I see it used in both long tons and short tons
My boat is recorded on the documentation as 13 tons,

but thats 26,000 lbs, is that wrong
Did you use long or short tons on the documentation?
A documentation person did that for me decades ago

Then an article turns around and says my keel is 9 tons alone
Well that is short tons
Some big boats have recorded weights in tons that are
a few tons more than my keel weight
Is that correct?
I'm getting confused

It is a measurement of internal volume, nothing to do with the weight of the vessel. When you say “the documentation” I presume you are referring to your USCG document.

https://www.dco.uscg.mil/Our-Organiz...tation-Center/

https://en.wikipedia.org/wiki/Gross_tonnage

[tkeithlu]

Point well taken Reading it again, "documentation" stands out. But the keel?

[Bill O]

This link gives a good explanation of the various ship tonnage terms.

[Adelie]

For the purposes of calculating “Tonnage” a ton is 100 cubic feet.

I believe this goes back to tuns of wine.

[toerail]

I didnt even think of metric tons
Now I am more confused

[toerail]

Yes and gross tonnage is volume as in how much cargo it can carry

[rslifkin]

The tonnage listed on USCG documentation is completely unrelated to weight. As an example, fully loaded, my boat weighs about 27,000 lbs. However, if I use the simplified method to calculate its tonnage for documentation purposes, it comes in at 25 gross tons, 20 net tons.

[toerail]

Thanks
I was wrong again
net tons is volume cargo
gross tons is the boat measurements in size
Then there is displacement tonnage

[toerail]

Thanks I just downloaded the USCG simplified calculation method and got 29.5 gross tons
My documentation isnt correct
And it cost me 600.00 by a professional
And they put 13 gross and 12 net
I dont know what they did
And I dont need these for ais or mmsi number is another thing I was looking at

[toerail]

Now when I see tons in an advertisement for sale or in a magazine article I will have no idea what they mean

[rslifkin]

Originally Posted by toerail

Now when I see tons in an advertisement for sale or in a magazine article I will have no idea what they mean

It depends on context. If they specify displacement, then you at least know it's weight. But it's still a question of which tons (long, short or metric) and whether that's dry weight or loaded weight.

[toerail]

Then there is lightweight displacement tonnage
Then there is deadweight displacement tonnage

[deblen]

And to confuse things a little more-DWT
https://en.wikipedia.org/wiki/Deadweight_tonnage