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Broad Reachin'
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Interested in keel design and the variables involved with mating a keel shape to a particular sailboat? Check out Bob Perry's excellent guest blog post: Keel Design According to Perry.

Big thanks to Bob for being willing to contribute to my blog and for being a part of the SN community.
 

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Hmmmm, Id like 6' of draft on my current boat, and I have 5.5........maybe an added lead bulb and a 5' taller mast some day.........next boat hopefully has at least 7' for a mid 30' boat, and 8' of close to 40'.............oh, I also sail where BP does, not sure the last time I saw actual digits on the depth guage, usually it is "---" or "last depth 55' " or some such number......oh well.........joys of a glacier dug area that was a mile thick!

Marty
 

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Sea Sprite 23 #110 (20)
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we can all only wish Marty.. the joys of sandy beaches and mud flats demands a more moderate amount of keel here on the east coast
 

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Around here if your depth sounder reads 25' you scream and do a crash tack.
So true.. but of course if it's reading 25 feet it probably read off scale 2 boatlengths back.. so you know it's coming up fast - and it's probably rock...

It would be really hard to get used to sailing in constant depths of single digit clearances.. but obviously one needs to in certain areas...:eek:
 

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Asleep at the wheel
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Ron, come over to the East coast. We'll take you out in Barnegat Bay where it basically never gets above 10', and average is 6-8'. Don't worry, it's very relaxing.

Bob and Kevin, thanks for the post!
 

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Around here if your depth sounder reads 25' you scream and do a crash tack.
On Barnegat Bay:

"What's the depth?"

"Reading 6 feet."

"Cool we've got plenty of water, I was worried we're getting too close to the shallow area." :laugher
 
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Try Florida Bay:

"Boating in the Florida Bay is a task for the skilled. Treacherous passes cut through long banks of mud and seagrass that separate the shallow basins that make up Florida Bay. Safe boating requires the ability to "read the water" as well as a chart. Shallow areas are not always marked, so polarized sunglasses are a key to reading the water. Having a weatherproof copy of NOAA chart #11451 is highly recommended. Visitors should know the limits of their boat. On average, the bay is less than 3 feet deep, so knowing the draft (depth) of your boat is important."

Florida Bay - Everglades National Park (U.S. National Park Service)
 

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Super Fuzzy Moderator
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So true.. but of course if it's reading 25 feet it probably read off scale 2 boatlengths back.. so you know it's coming up fast - and it's probably rock...

It would be really hard to get used to sailing in constant depths of single digit clearances.. but obviously one needs to in certain areas...:eek:
Not so much that we sail in single digit depths but almost always anchor in such.
 

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Not so much that we sail in single digit depths but almost always anchor in such.
I would like to anchor in single digit depths some time.

I would also like a windlass
 
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Around here if your depth sounder reads 25' you scream and do a crash tack.
Went sailing on the Sound last week with someone who had never been on a boat before, so we let him drive for a while. One of the other guys pointed to the depth sounder and said "Let us know when that's under a hundred"
 

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Daniel - Norsea 27
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Perhaps the reason I love my full keel so much is that I'm too stupid to understand the benefit of a fin keel. All I can say for sure is that when I'm out sailing my little full keeler I'm smiling so hard my face hurts.
Agreed! :D

Not switching for anything.
 

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Three years ago I sailed for some time a fast boat with 2.7m draft. I was used to 2.0m draft and I remember to thought that I needed to be really careful...but in the end I did not really noticed the difference except in the fun of sailing.:D

Not much difference in anchoring in 3.5m or 4.2m. Anyway most of the coves in Croatia are deeper than that.

It really depends on the cruising ground. If I sailed only there I could have a 3.0m draft without any problem.
 

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Mermaid Hunter
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Perhaps the reason I love my full keel so much is that I'm too stupid to understand the benefit of a fin keel. All I can say for sure is that when I'm out sailing my little full keeler I'm smiling so hard my face hurts.
Like Mr. Perry I'm happy for your happiness.

It is worth noting from an historical perspective that the reason "classic" boats had full keels was because we didn't have the ability to build anything else.

In today's world, the greatest benefit of full keels and their variants is lower draft. Bob Johnson has taken this concept pretty far with the three-digit Island Packets. The problem is getting the darn boat to point decently. If you want good lift and minimum wetted surface that means long span, short chord foils. The NACA symmetric shapes are really illuminating.

For myself, without resource constraints, I'd use a hydraulic lifting keel like some of the Moodys. 10-12' offshore and 5' inshore. In the meantime I'll live with my 6' Scheel keel boat.
 

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....

For myself, without resource constraints, I'd use a hydraulic lifting keel like some of the Moodys. 10-12' offshore and 5' inshore. In the meantime I'll live with my 6' Scheel keel boat.
What seems the most common solution for relatively small sailboats in this moment is a ballasted swing keel. Several production builders are using them.

They were perfected by Finot and allow drafts of 2.80 with the keel down and about 1.20m with the keel up. The two reasons why this system seems to be dominant is price but also the huge space constraints a lifting keel raises on a small boat. To be really effective a lifting keel box will go all the height of the cabin while a swing keel will only take the space under the saloon table.

Southerly use swing keels for a long time but that is not the same concept since they only take a part of the boat ballast while these relatively new ones take all the ballast in them.

Lifting keels are used now almost only in very expensive boats over 50ft, where you can find non intrusive space for them. They reach a high degree of reliability...but at the cost of a lot of money, specially for a small boat. In bigger boats the difference in price would not be so significant and many big yachts use them now.

The other type of keels used in small performance yachts not to lose a lot of pointing ability with a low draft are modern twin keels. The draft is not so low but on a 35ft they manage a good solution with about 1.6m and on a 40ft with about 2.0 m. This draft seems not too small but it corresponds in efficacy to a draft of about 30cms more, well, not really but the difference is small.

Regards

Paulo
 
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