How does one USE a waterline?

[Richandhelen]

Is this one of those "Everyone talks about the weather but no one does anything about it." situations? What does one actually DO with a waterline? Is it like a giant scale that tells you when you've exceeded half-load? Do you actually REMOVE things when that occurs? Is it for the Coast Guard to know when to board re. your suspicious load? Tells the yard when you boat is sinking at dockside? All of the above?

I can see the usefulness to freighters and large commercial vessels (although I suspect that they use more sophisticated lading calculating methods). It brings to mind the horrible ferry accident with great loss of life last year. Although on that one (Korea?) the height of the load came into play. Are waterlines a throwback? Are they there on our boats because the big boys have them?

 

[Don S/V ILLusion]

If you didn't have one, how would you know where to stop the bottom paint?

 

[Bill Roosa]

Other than limiting where I have to paint on the bottom paint and giving an indication of something wrong to a bystander while at the slip (bildge pump inop?) I can't think of a thing I'd use it for. Pretty much have to have it though for those things.

 

[woodster]

when i was in the army we had yellow paint on the prop tips and some one said that was to hold the black paint on the propeller...so the water line is used to keep the topside paint and the bottom paint from mixing it up and keep each paint color in it proper place....

the water line helps you know if your boat is low aft or forward or listing from one side or the other and also if you have loaded it very heavy oh and if you happen to see more bottom paint than usual below the water line you may be grounded

 

[thinwater]

If the OP means the boot top stripe, there are 2 cosmetic reasons:

1. Hides tannin and algae stains.

2. Makes the boat look longer and lower, which with most boats is a good thing.

And yes, I am aware of when the loading changes. In the Chesapeake, I can even see the boat go up and down with changes in harbor salinity (sinks after a hard rain--she is a little low now due to snowmelt)! No trivial, since many boats are quite sensitive to transom submergence.

 

[quadrille38]

If you didn't have a waterline how would you get a length at the waterline measurement in order to calculate theoretical hull speed? ?

Sorry I couldn't resist and definitely don't want to restart the whole hull speed thread again.

 

[topcat0399]

Without one how would we know the ocean was level????

 

[Stu Jackson]

I can't see it when I'm on the boat. Does this mean it disappears?

 

[Jackdaw]

Its kinda like your waistline. Gain weight, it moves up.

 

[Stu Jackson]

Hey, Jack, into suspenders yet? :dance:

In my case, it moved down because of the overhangs!!! (a truly nautical term!)

Up or down? Depends on your point of view: above the water or below it?

 

[centerline]

Without one how would we know the ocean was level????

AGAIN!!!!.... I thought Columbus definitively solved this one for us already

 

[Stu Jackson]

cl, I thought Columbus DISPROVED the flat earth theory??? It still is round, isn't it?

 

[centerline]

cl, I thought Columbus DISPROVED the flat earth theory??? It still is round, isn't it?

thats what i meant... he solved that riddle long ago...

 

[Stu Jackson]

But in your avatar picture and in all the pictures I take on the water, it still SEEMS flat!

 

[centerline]

But in your avatar picture and in all the pictures I take on the water, it still SEEMS flat!

Well its highly possible the bartender mixing your drink is holding back a little too much... when the waterline appears to have a bit of a slant to it, it'll be just right... and if the waterline appears vertical someting has gone terribly wrong...

 

[Benny17441]

I think you may be confusing the paint line with the waterline. The waterline is a constantly moving target where the wet and dry part of the hull meet.

 

[centerline]

I think you may be confusing the paint line with the waterline. The waterline is a constantly moving target where the wet and dry part of the hull meet.

I doesnt matter...After a few good drinks when you get a little bit sideways, everything is tilted a bit and in motion.... when you see either the waterline or the bootstripe go vertical, something has gone wrong!... hopefully you are still tied to the dock and all that has happend is that you over-amped your tolerance for capt morgan....and fell out of your chair.

 

[Allan12210]

If I didn't have a waterline length, then I wouldn't know how much of the hydrodynamic/aerodynamic interface I was using.

 

[jeffclown]

In the Navy, an important task for a new sailor might be to quickly procure 100 ft of waterline, which could require asking several others and a crusty old chief, with multiple chapters to the project. Similar mildly sadistic training was sending a new mechanic to the quartermasters (navy navigators) for a can of relative bearing grease - a must have item for engine maintenance. For any new boat owners... does the SBO store carry relative bearing grease?

 

[dparilla]

In the Navy, an important task for a new sailor might be to quickly procure 100 ft of waterline, which could require asking several others and a crusty old chief, with multiple chapters to the project. Similar mildly sadistic training was sending a new mechanic to the quartermasters (navy navigators) for a can of relative bearing grease - a must have item for engine maintenance. For any new boat owners... does the SBO store carry relative bearing grease?

No, but prop wash is on sale this week as is a Bosuns Punch