Mast height - measured from where?

[Liunatic]

So don't bash me, I'm still learning.

The manufacturer specs the mast as 54' 5.25" DWL

It is keel stepped.

So is the 54' and change measured from the waterline???
From the keel???
Or from the coach roof???

It must be waterline, right? But that number can vary depending on weight in the hull.

And if that's the case, how do I find out the length of my sail track? Go aloft with a tape measure?

[Wrong]

Originally Posted by Liunatic

So don't bash me, I'm still learning.

The manufacturer specs the mast as 54' 5.25" DWL

It is keel stepped.

So is the 54' and change measured from the waterline???
From the keel???
Or from the coach roof???

It must be waterline, right? But that number can vary depending on weight in the hull.

And if that's the case, how do I find out the length of my sail track? Go aloft with a tape measure?

Depends on what the measurement is to be used for. New sails? Clearing a bridge? Bragging about the length of your stick?

[Liunatic]

Wrong -

Looking to replace the sail track is what prompted the question, but, yeah, I suppose confidence in clearing a bridge would come in handy

No need to brag about the length of the stick, as it's the motion of the ocean that gets me there (said the female half of the Liunatic team)

[Wrong]

Originally Posted by Liunatic

Wrong -

Looking to replace the sail track is what prompted the question, but, yeah, I suppose confidence in clearing a bridge would come in handy

No need to brag about the length of the stick, as it's the motion of the ocean that gets me there (said the female half of the Liunatic team)

Me thinks measuring the sail track would be the best approach. Probably using a measuring tape attached to the halyard. However, without someone at the track top to ensure accuracy, eyeballing from the ground can introduce some error. What type of track will determine whether or not absolute accuracy is required. Of course if the new track is ordered with a little bit of extra length I imagine it can be cut to length once the old track is removed.

[Island Time O25]

You can start here and go from there.

Endeavour 40 Rig Specs, Parts & Rigging | Mauri Pro Sailing

Save yourself a mast climb as your main sail luff seems to be 42.9'(P) with a foot of 15.7'(E)

[Wrong]

Originally Posted by Island Time O25

You can start here and go from there.

Endeavour 40 Rig Specs, Parts & Rigging | Mauri Pro Sailing

Save yourself a mast climb as your main sail luff seems to be 42.9'(P) with a foot of 15.7'(E)

A precautionary comment. While specifications for sailboats are found online, I'd never trust their absolute accuracy. Especially if your boat is offered with different mast heights from the factory. I'd compare my eyeball measure from the ground using the measuring tape and halyard to the specification found online for peace of mind. Besides, just because boats from the same manufacturer in the same length, displacement and sail plan are presumed to be identical, workmanship and measuring of parts and pieces may not be identical.

[Jim Cate]

First, the mfg's number will indeed be from the design water line, and yes, your "air draft"changes with lading of the vessel. Further, these numbers are often only approximate, so don't trust them for fine tuning!


If you are planning on replacing the track in situ, you will be making lots of trips up the mast, and one now to make the proper measurement seems advisable. A little more info about your intentions will help us help you!

Jim

[Island Time O25]

Originally Posted by Wrong

A precautionary comment. While specifications for sailboats are found online, I'd never trust their absolute accuracy. Especially if your boat is offered with different mast heights from the factory. I'd compare my eyeball measure from the ground using the measuring tape and halyard to the specification found online for peace of mind. Besides, just because boats from the same manufacturer in the same length, displacement and sail plan are presumed to be identical, workmanship and measuring of parts and pieces may not be identical.

You're right. That's why I qualified my info as a start of the process and not the final word.

[Cheechako]

DWL would be from design waterline

[Liunatic]

I appreciate the advice. I would double and triple check the measurement before I order the mast track. Thinking about replacing the mast track is what got me onto the question of mast height.

I guess the more appropriate question is, what is the "design water line"? Is that where the bottom-paint line is?

So it's more of a general question I (very inartfully) posed, as opposed to any specific issue with my mast. I admittedly got off my intended topic by throwing the sail track in there. As the kids say, My bad.

[GordMay]

Originally Posted by Cheechako

DWL would be from design waterline

DWL is the designed water line, when the boat is loaded to its designed capacity.

[Kevin84]

Try not to use where the bottom paint stops as your tell tale for the DWL. Over time, it may have changed. I know a few people who have had to raise the waterline on their boats because they sat lower in the water once they were fully outfitted for cruising (more of a problem on some boats than others).

Sent from my SPH-L710 using Cruisers Sailing Forum mobile app

[StuM]

Also is that "mast height" or "air draft"?

My air draft is 1.35m higher than my mast height above DWL because of the antennae etc on top of it.

And at 21m it's a measured 2m more than the builder's specified "vertical clearance excl antenna" above the actual waterline.

[YellowBoat]

Originally Posted by GordMay

DWL is the designed water line, when the boat is loaded to its designed capacity.

And when the weight is more it doesnt really meke much difference.
A 10 meter yacht will have about 15-20 m2 surface on the waterline. So 1000 kgs more weight will give 1000/15 or 20 = 66 or 50 mm ( 2.6 or 2 inch) more draft / less mast height. At sea a bit less because seawater has a higher specific weight than sweet water.
Not really a value to take into account normally.
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[Les Crawford]

An old salt was watched shinning up his mast with a tape measure, and he kept falling down. A dock had asked what he was doing. Old salt sad, "trying to measure my mast height." Well then said the dock hand, "take the mast down and then measure it." The old salt looked at him and said " I want to know the height not the length."