Following on from my Westerly Riviera thread, another boat we're interested in has an hydraulically operated lifting keel. Does anyone have one of these? Pro's and con's please!
The boat is a Jeanneau Sun Fizz 40.
I feel I should warn you, there may be a few similar posts in the coming weeks/months but as we're moving from power to sail I thought it best to ask the folks in the know
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Thread: Lifting Keels
24-02-12, 09:48 #1
Lifting Keels'I will not be pushed, filed, stamped, indexed, briefed, debriefed or numbered! My life is my own!'
24-02-12, 09:56 #2
I'm sure they could cut you are great deal. Ok, so it'll need a bit of work, what with the absence of a coachroof and all (after the explosion), but great for a bit of DIY.
Seriously, though. If theirs was a lifting keel version, they must have had some experience of the mechanism.
24-02-12, 10:42 #3
I'm pretty sure the crash test boat was a fixed fin keel.
Pros: wider cruising range, more flexibility (=cheaper) berthing. Depending on configuration you may be able to beach the boat on sand/mud safely. These things may not matter to you if you only cruise deep water and are happy to pay for a full depth mooring or berth.
Cons: can take up space inside the cabin, it's another system to maintain, the keel can itself be difficult to get access to if it can't be locked down in such a way that it can take the boat's whole weight.
Other more knowledgeable people will probably be along shortly...
24-02-12, 11:44 #4
The lift keel on a Sunfizz doesn't impinge on cabin space I believe as it stows inside the fixed keel stub I think. I have no knowledge of it otherwise.
However Sailing Today I'm pretty sure tested a used lift keel one way back 12/13 years ago) so might have back copies available. I used to have a copy but had a clearout a while back. Also pretty sure YM tested the earlier Sunfizz 40 so same applies, but probably fixed fin.
One of the slight downsides is how to paint the lift keel bit, but a bit of negotiation with the boatlift and yard staff can work miracles for the price of some beer tokens.
We have friends with a very beautiful Alan Hill 40ft wooden lift keel ketch that they have had in the family from new. They have legs for drying out in places others cannot reach and use the shallower draught to very good effect, plus the boat has been well proven in bad weather many times. Different boat of course but if seakeeping ability of a lift keel was a concern i don't think it should be.Sermons from my pulpit are with tongue firmly in cheek and without any warranty!
24-02-12, 12:08 #5
Getting access to the keel on land was a nightmare. It would have helped to have a cradle tall enough to let the keel drop. I had to make do with a lot of jacking and blocking - it made me pretty nervous.
Note that if the keel can't be locked in the down position, stability has to be calculated with it in the 'up' position for purposes of coding etc.One hull good, two hulls better.
24-02-12, 12:21 #6
24-02-12, 12:23 #7Registered User
- Join Date
- Nov 2007
Lift keel boats have been more popular in France because of their large numbers of drying harbours. Their designs tend to use stub keels to minimise protrusion of the keel box into the cabin, but does mean that they are not so easy to dry out without legs, although it also means that rudders can be deeper than in flat bottomed boats.
Once you accept those trade offs compared with a fixed keel of the same design, the other major issue is maintenance - as already mentioned the difficulty of getting at the drop keel to anti foul, but probably of more relevance on an older boat, maintenance/replacement of the pivot bolt and hydraulic lifting mechanism. More things to go wrong, but probably not a big issue if well maintained.
24-02-12, 13:04 #8
24-02-12, 13:11 #9Registered User
Location : Southampton
- Join Date
- Nov 2009
24-02-12, 13:32 #10
our Parker 31 (1990) has a 1000+ kg 1.7 m lifting keel. It is operated with a substantial hydraulic pump and ram, operating two SS cables on pulleys (roved to disadvantage). Later models have just the ramrod operating the keel directly.
Pros: easy and fast lifting, quite safe (an hydraulic valve opens at the end of travel).
Disadvantages: to lift, you need at least a 100 Ah (I have 220) battery to operate, and if possible, running the engine as well. But no power needed for lowering the keel, it drops by gravity. Two 25 mm rubber tubes running from the cockpit to the foot of the mast.
- own problems : wear on the cables and aluminium pulleys.
- known problems from fellow owners: leaking hydraulic fluid from ramrod and couplings. Chafe on the tubing in the bilge. Wear and sometimes, cracking of the synthetic blocks which guide the keel. Complicated and delicate height measurement system.
Incidentally, a Dutch sailing friend made a system up himself with forklift parts. He hasn't had any problems so far.
Last edited by thalassa; 24-02-12 at 16:31.Parker 31/14 'Alchemist'