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Old 03-18-2017, 04:42 PM
Podowitz Podowitz is offline
 
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Bilge keel conversion a la Westerly Centaur

I sail in pretty skinny waters. A friend has a Pearson 30 that's been on the hard for a number of years. Motor gone but bracket on the stern. No blisters, no soft spots. Yard offered to take over the boat for the keel salvage and cut the boat up. I was thinking of taking over the boat, surrendering the keel to the yard, and outfitting the boat with a shallower pair of bilge keels. Please share your thoughts on how to accomplish, No naysayers please; I already know it's a little crazy.
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Old 03-18-2017, 06:06 PM
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gonzo gonzo is offline
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If you give the keel away, you'll have to go and buy the equivalent amount of metal to make the new keels. The plan makes no sense.
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  #3  
Old 03-20-2017, 03:07 PM
keith66 keith66 is offline
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Buy a shallow draft boat to start with & save yourself a world of agravation.
Westerly centaurs draw about 3ft 6", plenty for sale over here for not a lot of money. They do suffer from the keels falling off though.
If you insist on doing it it is possible. A local yachtsman took a Hunter Sonata fin keeler, removed the deep fin keel & fitted bilge keels to her, he did a lot of research & designed them properly & did a splendid job. She sails very well & he has put a lot of miles on her.
The fact remains it is never ever going to be an economic proposition.
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Old 03-20-2017, 05:33 PM
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Angélique Angélique is offline
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Quote:
Originally Posted by Podowitz View Post
Bilge keel conversion a la Westerly Centaur
I sail in pretty skinny waters. A friend has a Pearson 30 that's been on the hard for a number of years. Motor gone but bracket on the stern. No blisters, no soft spots. Yard offered to take over the boat for the keel salvage and cut the boat up. I was thinking of taking over the boat, surrendering the keel to the yard, and outfitting the boat with a shallower pair of bilge keels.
Hi Podowitz, if ever doing it . .
Then better go for less wetted surface, so less hull resistance, plus a lower center of gravity for the same draft, so enhanced stability, compared to the traditional Westerly Centaur type of bilge keels, and add NACA profile bilge keels with bulbs à la the RM 880 . . .

Quote:
You probably also have to adapt the Pearson 30 rudder to the new draft as well I guess . .

And while at it, best also make a outboard well instead of the stern bracket ---> Atom Voyages ---> The Inside Outboard.

Or buy a boat that suits you as it is, and go sailing right away . . .
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Last edited by Angélique : 03-21-2017 at 06:32 PM. Reason: added center of gravity and stability info in the first line
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Old 03-21-2017, 08:19 PM
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Angélique Angélique is offline
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There's a 26' steel bilge keeler build in the threads Never say never and in 25.6ft Gaff Cruiser under way Quote: Pics = Post #1, Text = Post #4

Quote:
Originally Posted by Wynand N
- - - - - - - - - - - - click thumbs to enlarge - - - - - - - - - - - -
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Bilge keels toed in 1.5° each, and canted 15° outwards.
Note that the previous posted NACA profile bilge keels need to be toed in and canted outwards as in the above quote I think, but the bulbs centerline could be best flush with the boat's centerline and the waterline I believe, to have least resistance.

Also note that the Pearson 30 has an encapsulated fin keel, so extra bottom repair is needed there when the fin keel is removed, and the bilge keel attachments through the hull need internal hull reinforcements, also the bilge keels and the adapted rudder with the new draft need to be firm enough to stand on when drying out, and take some boat jumps by waves when just more or less standing.

Please keep us informed of your plans, and if you decided to start, the progress of project, and eventually the sailing results . .

Good Luck !
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Old 03-22-2017, 12:22 AM
Stumble Stumble is offline
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Just buy a shallow draft boat. Trying to retrofit bilge keels would be an absolute distaster unless you spend more on an engineer to figure out the local reinforment needed to support the loads.

You could probably buy a mid size cat for the conversion costs.
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Old 03-22-2017, 02:27 AM
keith66 keith66 is offline
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Never mind spending out on an engineer to calculate loads. Westerly yachts were professionally designed & sold like hot cakes & yet their keels fell off with monotonous regularity. This resulted in a product recall on all centaurs to strengthen them. Despite this many didnt get fixed & in the last 10 years in our yacht club alone 4 Centaurs, 2 Konsorts & 2 Discus's have had severe hull to keel problems, two of these sunk on drying moorings (sheltered). The common thread on three of them was soft mud where the keels went in a long way & the keels got wrung as the boat lifted with the tide. Others just gave up due to long general use.
Though it can be done its an absolute certainty to be uneconomic to do. You will have to gut the saloon down to the hull skin, strengthen the skin itself at each proposed keel location & fit at least 4 floors extending 2ft each side of the keel, you will use a lot of fibreglass, then you have to put all the bunks, floor etc back in again, much of this is structural to some degree. Then you have to source keels, on a Centaur sized boat they will be half a ton each, with an efficient splayed configuration you need a lifting gantry to hang the boat in to fit them. Out of interest the cost of reinforcing a Westerly Centaur properly by a boatyard is anywhere from £7500 to £10,000 You can buy a lot of yacht for that money ready to go. Your best bet is to buy a shallow draft boat that works, go sailing & eat steak.
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Old 03-22-2017, 10:50 AM
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PAR PAR is offline
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Your idea can work, though you'll need nearly two tons of lead to replace what's being sold off the Pearson 30. You'll also need to engineer and build a couple of keels, which isn't a small feat, even if you're a reasonably skilled builder. Costs aside, this would be major surgery and will require a good investment in time and materials.
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