Displacement numbers

[Kd9truck]

Happy Fathers Day, so I am wondering about the published “displacement” numbers (like sailboatdata.com) are they with fuel and water weight or is it the dry weight. My vessel is 3000 lbs heavier “wet”. I am contemplating adding tankage for off shore ballist.
Ty in advance.

[Bowdrie]

Have no idea about the new crop of designers.
In the "old days", it was common to give the disp. figure with ~1/2 load of fuel and water plus what the designer figured was a "reasonable" amount for miscellaneous gear and supplies.

[TrentePieds]

kd9 sez: "I am contemplating adding tankage for off shore ballist"

If it's ballast you need, then tankage is probably not the best way to do it, cos fresh water is lighter than saltwater (i.e it has lower specific gravity) and fuel is lighter still. Lead is the thing to use for ballast, because, if memory serves, it is eleven times heavier that freshwater. And it doesn't slosh about :-)

But I think it is doubtful that you need additional ballast. Your thinking probably is that that would help the boat "stay on her feet" in a high wind. If the boat gets to heeling to the point where you think more ballast would be good, you are carrying too much sail! You will find that when your boat heels 10 or 12 degrees when you are "on the wind" she will be going at "hull speed", so you can't make her go any faster whatever you do, and compelling her to carry more canvas merely strains the gear.

In light winds, you obviously don't need more ballast. Your job as skipper is to determine what amount of sail will make her heel 12º in the prevailing conditions. You add sail or reduce sail to achieve that happy state.

As for "additional" weight, the less you have, the better from a performance perspective. Carry the clobber you need for you planned passage, forget about additional ballast and sail the boat sensibly.

All the best :-)!

TrentePieds

[Mike OReilly]

I have no idea where the sailboatdata comes up with their data. I know my boat is listed at 26,500#, but a recent crane operator called out 30,000 Pounds!

[SailingHarmonie]

Adding weight is rarely a good idea. It CAN help when sailing to windward, but only if it is low enough and on the centerline that it actually improves stability.

Extra weight is always bad for performance downwind.

[HankOnthewater]

I can not answer your questions, but there has been threads that discussed issues about displacement.
https://www.cruisersforum.com/forums...nt-204971.html
https://www.cruisersforum.com/forums...tc-174752.html

about sailboat data...... I know quite a few errors or genuine mistakes are in that repository.
about travel-lifts....... The weight scales of these are generally not very accurate

[MicHughV]

My best guess is that 99.99% of sailors out there have raised their boot stripe by several inches to accommodate an ever burgeoning array of "stuff" that comes out of nowhere and disappears into spaces and gets forgotten.

Having bought and sold several sailboats, it never ceases to amaze me when it comes time to move out of the old boat into the new, the amount of stuff I dig out of lockers that I had long forgotten about. It becomes a veritable "mountain" of stuff on the dock that my disbelieving eyes ask...."is all that my stuff ?.....

[Celestialsailor]

trust me...if you go cruising, you will have more ballast than you want after packing all that "necessary" s#!t in your boat before you leave.

[Bowdrie]

Originally Posted by Celestialsailor

trust me...if you go cruising, you will have more ballast than you want after packing all that "necessary" s#!t in your boat before you leave.

Sure enough.
You'll need several sizes of Crescent wrenches, both metric and SAE in both left and right hand configuration.

[GordMay]

Doesn’t the ISO Small Craft Standard specify "light-craft condition", that includes the weight of basic gear, but assumes empty fuel and water tanks, in it’s buoyancy assessment?

[Pete7]

Originally Posted by GordMay

Doesn’t the ISO Small Craft Standard specify "light-craft condition", that includes the weight of basic gear, but assumes empty fuel and water tanks, in it’s buoyancy assessment?

Might even be more extreme that that, depending on how the manufacturer decides to market it. So no anchor, chain, cushions or sails. Engine empty of coolant and oil? who knows.

I am sure sailboat data comes from the manufacturers brochures.

[Kd9truck]

Originally Posted by Mike OReilly

I have no idea where the sailboatdata comes up with their data. I know my boat is listed at 26,500#, but a recent crane operator called out 30,000 Pounds!

Yes, thank you Mike, I remember hearing or reading that before and it sounds like it’s a simple common answer. Cheers

[Pegu Club]

According to Sailboat data, our boat goes in at 8650 Lbs, I have always assume that was dry weight. As reference in an above post, reducing sail is the way to go if you are feeling that one is in a state of being over canvased, and wanting to be in a more comfortable state while at sail.

Fair winds,

[MicHughV]

What if car manufacturer's stated..."this car comes in at 3,500 lbs, without wheels, seats or engine...optional extra's which may affect trim and performance of car..

[Kd9truck]

TP say: But I think it is doubtful that you need additional ballast.

All the best :-)!

TrentePieds[/QUOTE]

TY Tp

Thank you TP, I agree with all of your thoughtful sentiments, It’s not a need it’s a want. I want more fresh water and fuel tankage for “options”.
1. being a non mechanical back up to a watermaker 2. as a way to redistribute water to and from my front tank. 3 as a tool to tweak balance and performance, racers have human ballast the move all the time.)
It would be of occasional use, a great many off shore vessels with diverse intentions use liquid to balance their vessels seakeeping ability. I am neurologically an outside the box guy. I sail my vessel at 80% during the day and 60-70% at night, so not looking to push past the limit of my vessels design.
I do like to tinker, so I have been told.
Cheers