SailNet Community banner
  • SailNet is a forum community dedicated to Sailing enthusiasts. Come join the discussion about sailing, modifications, classifieds, troubleshooting, repairs, reviews, maintenance, and more!

Full or Shoal Keel on New Oyster 575?

15K views 50 replies 9 participants last post by  blt2ski 
#1 ·
I've purchased a new Oyster 575 and will need to make a "keel decision" in the next few months. While we will be bringing it across the Atlantic, most of the intended sailing will be in the Caribbean, out of the BVI. There are lots of opinions and I want to make the right decision - "realities" of the destinations versus all the performance concerns (pointing, leeway, stability, etc.). FYI, we are cruisers, not racers.

Short of a crystal ball, I'm amassing thoughts/perspectives form those of you who have "been there, done that".

Thanks so much.
 
#16 ·
NINE FEET!???

Hope you enjoy the carribean cuz you sure aint bringing that boat to the keys or Bahamas... And if you ever want to sell it, where would you sell it? Having a boat with that kind of draft would wipe out any buyers that wanted to use it in my neck of the woods.

I guess you know what my answer is. But in full disclosure, I hate 6 feet (what mine is).

Brian
 
#5 ·
That is the same draft as my boat and with almost 9 feet of draft I haven't felt myself constrained much. I keep my boat at Nanny Cay in the off season and getting to the haulout pit can be a bit challenging due to some shoaling and one can't get into Anegada but in calm weather one can always anchor outside the entrance markers with the other "big boys" :)

Although one can head out to a marina inside the lagoon in St. Martin, the anchorage is out - the only place I found to anchor was still halfway inside the channel and I was still churning up muck with the keel while swinging at anchor.

After that the anchorages further south are all deep enough for a deep keel, sometimes I end up anchoring further out in places such as Deshaies or Portsmouth in Dominica, but that's not necessarily a bad thing.

The only place that is going to be off limits, if I intended on heading that far up north, is the Bahamas.

All in all I like my deep keel and given a choice wouldn't reconsider and go for a shoal keel.
 
#6 ·
Zanchin, do you notice a significant cruising advantage of the performance keel under sail? You note a couple of basic advantages of the shoal keels around shore, where you have trouble getting to the travel lift or into popular anchorages. In my way of thinking, cruisers spend more time around shore than sailing. (Unless one sails more than 12 hrs a day, everyday :) )

Everyone should love their boat and have it the way they like it. I'm not suggesting there is a right and wrong.
 
#7 ·
Minne,

Some of the issue may also depend upon the how hard one ones to think/work at getting into a given marina, haul out etc. If one wants to go there at any time, one needs a draft that equals the lowest range. If one does not have an issue with thinking, planning etc, then one can go with a deeper draft! Then get the sailing benifits of the deeper draft boat.

If one wanted BOTH options, then one has to figure out how to have a CB or lifting daggerboard as some LARGER boat manufactures are offering. If the OP has this option, I personally would go that route, then deep draft, last after exhausting ALL OTHER options would be a shoal draft. Assuming one is going to have draft issues everywhere they go. I would have a hard time assuming EVERYWHERE there will be draft issues with the drafts mentioned.

Marty
 
#8 ·
My question, however, is how much of a difference in performance is there for cruising? For one, I find the shoal keel to make very little difference. I'm sure I slide a bit more to leeward at the highest point, but I'm cruising, not racing to a mark. If I have any room to spare, I may just have to point a tad higher than the performance keel, then there is virtually no difference in VMG.

On the other hand, having a shallower draft is clearly an advantage around the shore.

Again, I have no beef with anyone that wants a deep keel for cruising. I just haven't heard anyone even attempt an explanation on its cruising advantage. To me, it seems that slight advantage would be lost, while I was eating a sandwich on a cruise and failing to trim properly.
 
#9 · (Edited)
There is no substitute for draft.
To say the performance difference is negligable is not correct if you are looking at VMG's.

But if draft prevents you from going where you want to go I would consider that "poor" performance.

I would ask the builder to provide you with VPP print outs, not just polar plots but the entire print out and then you can see for yourself to three decimal places exactly what the difference in performance is. No need to guess. Be scientific about it. Wear a white lab coat. Put something important looking in the pocket.
 
#10 ·
Minne,

While as you say, you may need a bit extra to eat a sandwich with a shoal vs a deep. Assuming you only sail 10-50 miles to a place, anchor/dock etc for the night. Lets look at this from say a 2000 mile jaunt! A typical shoal vs deep draft is slower by 20-30 secs a mile in PHRF ratings. With this in mind, I realize put an AC crew in the shoal draft with bad sail, they will knock the socks off of a very well prepped but poor crewed deep draft of the same model!

lets say it is 2000 miles, at 20 secs a mile that is 28 hrs or there abouts if I did my figuring correct. A bit more than eating a sandwich. at 30 secs that is 42 hrs! A bunch of time in some cases.

Some say having a folding/feathering prop is not worth the expense, because they are cruising. I would say .5-.75 kph is also something to think about, as that is an extra 12-18 miles per day! Potentially as much as 24 for some boats. Again, over a 2000 mile stretch, that adds up to a day or two getting there sooner, less food etc to pack, potentially out running a storm or equal, reality is quite unlikely!

In our local race fleet, we have three of us with 28'ish foot on deck boats, my Jeanneau Arcadia, Cal T2, and a catalina 28 mk II. All have simalar hull deminsions. The C28 a shoal keel at 4' the T2's are ar 4.5, my Arcadia is 5.5'. WHen we have things going right, we can out point the T2's by 3-5*, the T2's out point the C28 by 3-5* also. Hence in this size boat, setups, why there is a 20 some odd sec spread in the boat ratings.

I guess if you do not care how long it takes to get somewhere, then the deep draft vs shoal is not an issue....... In my mind, if a person can afford an Oyster new, assuming the OP is buying a new one, I would swag Oyster would be willing to modify that boat with a dagger board frankly at a 5-10% max cost increase, so for me, well worth it to get the best of both worlds!

Marty
 
#13 ·
How about 5' on a 43' boat? We have a bene DS43 in the fleet, I can out point that on by some 10*. At a race afew weeks back, while they did the same 2 mile or so upwind leg in the same amount of time i did, they had to sail at least 50% more distance than I did! so not sure where the 40 secs a mile they have on me helps them!

sailing is fun, to me make it fun from your stand point. For me, the faster I can go, more upright etc is the way to do it, Deep keels make this and easier option than a shoal with a in mast furling like the 43ds I have mentioned. Or the C28II. THe T2's frankly do move along and those boats are hard to beat. They might have a bit of a gift rating, or since the owners have owned them for a LONG time, they probably know every current, how to set the sails perfect ea time etc.......

Marty
 
#15 ·
Is the PHRF on the particular boat in question actually different by 20-30 seconds per mile between the shoal and deep keel? If so, I get it. That would be a lot more than I expected. On my boat, I find it hard to image it would be the case, but I could be wrong.

However, I don't think cruisers do very many 2000 mile legs, with 50 to maybe 100 mile days being most common.

I guess the OPs answer will somewhat depend on what they mean by cruising.
 
#17 ·
SWAN 53 CB SM 48 48 48
SWAN 53 DK SM 30 30 30
SWAN 53 SM SD 42 42 42
Mcgregor 65 std keel -45 shoal draft -9 wing keel 15
J44 36 vs 45 for the WK
Islander Peterson 40 87 for DK 111 for the shoal draft
Gulfstar 60 48 to 57
Grand soliel 39 108 vs 120
catalina 400 117 vs 126
Bene Oceanus 473 78 vs 96

Not too many larger boats like this in phrf. If I were to look up IRC/IRS or one of the more common rating systems in Europe, I could probably find ratings for Oysters. In NQ where PHRF is king, no one else in the world uses this system too much.... hard to get comparisons. But the few I did find in larger boats, there is at least a 12-20 sec difference. Even Minne's boat is not listed, be it shoal or deep draft, as no one has raced it, or not enough have raced to get into the system to look up at this time.

One can see that there is a difference in speed. As I sorta pointed out, as did minne, if you only go 10-50 miles then hit a dock....probably not enough to make a big deal out of. If you cross oceans or equal for a 2-4 day trip......now things will change a bit!

I still say, if one needs shoal, yet wants the deep draft pointing ability, a daggerboard or CB would be the way to go. But many of those seem to be slower in ratings than a shoal is! Probably because the board does not carry a lot of the ballast, and MOST of it is in the upper keel area, so the thing is BOGGED down by a LOT more wt. Vs a deep vs shoal can be 300-500 lbs for a boat my size, to 3000-5000 lbs for boats in the 40's and 50 foot range. A bunch of added wt to get the same righting moment, then add in drift, lack of pointing........adds up, whether a person cares or not is another story.

Marty
 
#18 ·
Marty:
Problem is if we are comparing a 6' draft Oyster to a 10' draft Oyster you are NOT going to get the same Rm. I don't care what humungous shape that they hang on that 6' keel tip. You will never get the VCG of the 10' draft model. And just adding ballast will have it's own set of negative effects.

Go now.
Go deep.
Don't go to the Bahamas.
 
#19 ·
Bob,

I would have no doubt there would be a BIG difference in 4' as to how much lead one would have to add. Hence why the CB versions of some of the boats have such a slow rating, the lead is probably all in the upper 2-3' of the keel per say, in the housing below the hull. Now that I typed all that giberish, not sure if it made sense.......hopefully it did.

Now if I could figure out how to make my current boat 6' deep! then put the lake rig on it......not sure what that would do to the rating or speed or what ever.....probably not worth it frankly, better to spend some money on a proper designed boat in the mid 30' range, wife would be happy as it is bigger, for me faster.........

If I could afford an oyster, not sure 4' would be an issue, or the putting a daggerboard like Icon has or some of the other larger boats in the Oysters class of boats. That would be my way to deal with this issue. Not that 10' here in the salish sea is an issue, other than Fishermans bay on lopez or slot going thru laconner. Even those places one could get a 10' draft thru them if one had to. FB would be the harder one! Since at 0 it is 5' deep or there abouts, max I have seen is 9', so 13' of water to deal with......hmmmmmmm.

Marty
 
#21 ·
Oh, I'm a simple man.
Shoal draft Oyster? Deep draft Oyster?
Who am I to quibble with details?
It's an Oyster.

But I get a great satisfaction of making a boat go to it's supreme potential. If a boat has a birth defect that is crippling it's performance I am not happy. Not happy when I am sailing. Maybe I'm happy when I'm on the hook and the little drinks are coming out with little umbrellas in them. I like foix gras.
 
#22 ·
I have also ordered a new 575 - delivery next summer:) My strong advice: Stay with the standard keel if not absolutely required from you planned cruising ground. Shoal keel will have significant negative impact on sailing performance and boat behaviour. In the Med and the Caribbean draft is normally not a problem. Around the BVI, you have to take care when approaching Anegada, all other places draft is not an issue.
 
#23 ·
Chione,

Thanks for the post - lucky you for taking delivery next summer. We're hull 28 (608 days to go) so now the waiting game. I've come to the same conclusion after talking to sailing friends far and wide. The few places we may have to give up (i.e. the Bahamas) seem to be outweighed by performance characteristics of a full keel.

Thanks again and have a great weekend.

Rhammill
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top