bluff
New member
hi folks,just wondering has anyone had problems with lifting keels slipping back into the up position during a knockdown and slapping down when the boat rights
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lifting keels
- Thread starter bluff
- Start date
T_S
New member
I own a Seal 22...and I don't intend to invert it to find out! /forums/images/icons/smile.gif
<hr width=100% size=1>Trailer Sailors get there by road!
<hr width=100% size=1>Trailer Sailors get there by road!
Egbod
Member
I know of a new small Parker (235 ?) that was knocked down in force 8 conditions by a very severe gust coming off the nearby land. The mast head was in the water for a time. I am not aware of any suggestion that the keel moved in. Most boats do not have all of the ballast is in the lifting keel.
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T_S
New member
Well on the Seal 22 the keel weighs around 800 lb, I think it could if the boat was inverted smash through the hull! A friend of mine whom owns a 28 has a similar fear as I do, we regularly discuss about making some sort of locking device to prevent this disaster from possibly happening.
<hr width=100% size=1>Trailer Sailors get there by road!
<hr width=100% size=1>Trailer Sailors get there by road!
William_H
Well-known member
I am assuming that by lifting keel you mean a vertically lifting keel as opposed to a swing keel. Mine is vertically lifting about 100kg of molded F/G with lead inside. In Oz the trailer sailer rules requires that the keel be locked down when sailing although the boat is required to be self righting with the keel retracted. My boat originally came with a clamp arrangement across the top of the C/B case which stopped the C/B retracting very far. After running aground (many times) I found that the thin traing edge of the C/B was crunched in where the C/B tilted back against the aft end of the slot. The fix which worked well is to put a 5/16 inch bolt through the case at the aft end with nil clearance between the bolt and the top of the C/B. Now after a high speed run aground the bolt gets a little bent but no damage to the aft end of the keel so it works well. I put extra layers of F/G around the place where the bolt goes through each side of the case for fear of glass failure.
[http://au.msnusers.com/CASTLE650GROUP] might give you some ideas. lets hear it for trailer sailers. regards will
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[http://au.msnusers.com/CASTLE650GROUP] might give you some ideas. lets hear it for trailer sailers. regards will
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seumask
Well-known member
In our lift Keeler Hunter Delta, the keel (700KG)is bolted down by 4 bolts, and we only ever unbolt it when we know we are about to go aground (intenionally or unintentionally), If the bolts are not tight and there is is any wave action you can feel a slight knocking as the boat pitches which is a excellent reminder to check the keel botls in less than clement conditions.
However I did hear of a similar sized lift keeler, being sailed in fresh conditions by some dinghy sailor who wound the keel up condierably whilst reaching to gain extra speed and then unfortuanlty broached the boat. This resulted in the boat sinking, mainly because the boat would not self right because the keel was a vertical lift type and was now exerting no usefull righting moment.
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However I did hear of a similar sized lift keeler, being sailed in fresh conditions by some dinghy sailor who wound the keel up condierably whilst reaching to gain extra speed and then unfortuanlty broached the boat. This resulted in the boat sinking, mainly because the boat would not self right because the keel was a vertical lift type and was now exerting no usefull righting moment.
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kds
New member
This concern was adressed by modification to the original Atalanta (26' Uffa Fox design, twin lifting keels) by the positioning of a strut to prevent it happening.
Ken
<hr width=100% size=1><A target="_blank" HREF=http://www.canongrange.co.uk>Bed and Breakfast, cathedral Green Wells, Somerset Canon Grange</A>
Ken
<hr width=100% size=1><A target="_blank" HREF=http://www.canongrange.co.uk>Bed and Breakfast, cathedral Green Wells, Somerset Canon Grange</A>
charles_reed
Active member
Parker lift keels
I have the pre-production prototype 31 which uses wire strops on a 2:1 displacement ram.
On the later versions the keel ram is direct acting and keeps the keel in position.
I have had a B2 knockdown and the keel didn't move, However i do have a through-bolt which goes through the top retaining flanges which are about 150mm above the waterlevel in the box. With 2150 lbs of lead and a lift of 1212mm the keel movement could produce an impressive impact.
Angus Primrose, who designed the Seal 22 and had #1, had a 28mm stainless tube, which he used to fit through the table top and to the deckhead to keep the cast-iron keel of the Seal 22 in position. Getting it in was a feat of legerdemain. Of course if you do have a B3 the keel is designed to lift out from on top and will probably carry away the table top before emerging.
Angus did stress that it was a coastal sailboat and anyone who took it offshore should be locked up as insane and a threat to their own survival. I used to cross the channel regularly with mine though - great little boat.
In the case of your mate with the Super Seal/Parker 28, designed by Ron Holland, he has little to worry about as the majority of the ballast is a casting bonded into the bottom of the boat and the board is a centreboard with (from memory 200 lbs) to make sure it has negative bouyancy.
Incidentally, of all the Seals (including the 31/32.5), only the SuperSeal should ever be sailed with board up.
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I have the pre-production prototype 31 which uses wire strops on a 2:1 displacement ram.
On the later versions the keel ram is direct acting and keeps the keel in position.
I have had a B2 knockdown and the keel didn't move, However i do have a through-bolt which goes through the top retaining flanges which are about 150mm above the waterlevel in the box. With 2150 lbs of lead and a lift of 1212mm the keel movement could produce an impressive impact.
Angus Primrose, who designed the Seal 22 and had #1, had a 28mm stainless tube, which he used to fit through the table top and to the deckhead to keep the cast-iron keel of the Seal 22 in position. Getting it in was a feat of legerdemain. Of course if you do have a B3 the keel is designed to lift out from on top and will probably carry away the table top before emerging.
Angus did stress that it was a coastal sailboat and anyone who took it offshore should be locked up as insane and a threat to their own survival. I used to cross the channel regularly with mine though - great little boat.
In the case of your mate with the Super Seal/Parker 28, designed by Ron Holland, he has little to worry about as the majority of the ballast is a casting bonded into the bottom of the boat and the board is a centreboard with (from memory 200 lbs) to make sure it has negative bouyancy.
Incidentally, of all the Seals (including the 31/32.5), only the SuperSeal should ever be sailed with board up.
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Seal_surfer
New member
Re: Parker lift keels
A few pedantic corrections:
As owner of Superseal 26 and until recently a Seal 22, I must just point out a couple of details to avoid misunderstanding.
It is the Superseal 26 and 27 models that have a lightish (~300Ib) daggerboard that can be safely raised during sailing, as the vast majority of ballast is bonded in internally. Very exhilerating boats.
The Seal 28 is a much more serious (voluminous and higher displacement) cruiser that uses a heavy ballasted cast iron keel similar (but much larger) to the Seal 22, with a substantial flat bottomed bulb at the base.
Therefore, the keel cannot come up through table top in a knockdown unless the bulb completely smashes through the GRP keel stub and slot area - quite posssible I suppose. So keel is removed from below - I've done it for maintenance.
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A few pedantic corrections:
As owner of Superseal 26 and until recently a Seal 22, I must just point out a couple of details to avoid misunderstanding.
It is the Superseal 26 and 27 models that have a lightish (~300Ib) daggerboard that can be safely raised during sailing, as the vast majority of ballast is bonded in internally. Very exhilerating boats.
The Seal 28 is a much more serious (voluminous and higher displacement) cruiser that uses a heavy ballasted cast iron keel similar (but much larger) to the Seal 22, with a substantial flat bottomed bulb at the base.
Therefore, the keel cannot come up through table top in a knockdown unless the bulb completely smashes through the GRP keel stub and slot area - quite posssible I suppose. So keel is removed from below - I've done it for maintenance.
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charles_reed
Active member
Seal 28
Yes the aft cabin 28', which used the same keel as the 22' but had additional ballast.
Or so the designer told me.
I had unintentionally ignored that one and quite right, thekeel box is totally enclosed.
I'd suggest 800 lbs is a fairly heavy keel.
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Yes the aft cabin 28', which used the same keel as the 22' but had additional ballast.
Or so the designer told me.
I had unintentionally ignored that one and quite right, thekeel box is totally enclosed.
I'd suggest 800 lbs is a fairly heavy keel.
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bluff
New member
Re: Seal 28
thanks for all the replies i nearly had a beneteau 24 drop keel bought which didnt survey well ,aftertwards i read of a beny 235 which did the keel up down thing
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thanks for all the replies i nearly had a beneteau 24 drop keel bought which didnt survey well ,aftertwards i read of a beny 235 which did the keel up down thing
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T_S
New member
Re: Seal 28
Yes great boats the Seals, but if the 22 or 28 were broached I cannot help wondering what 800lbs of solid cast iron could do to plastic!
<hr width=100% size=1>Trailer Sailors get there by road!
Yes great boats the Seals, but if the 22 or 28 were broached I cannot help wondering what 800lbs of solid cast iron could do to plastic!
<hr width=100% size=1>Trailer Sailors get there by road!
Avocet
Well-known member
Re: Seal 28
We used to have an Evolution 22 with a lifting dagger board on a little mechanical winch. It had a huge stainless bar (about 40mm diameter from memory!) which slid through a hole in each side of the top of the keel housing and through the top of the keel itself - i.e. into the housing, through the keel and out of the other side of the housing. It was quick and easy to fit and although we never got knocked down, it helped stopping the keel knocking against the housing when the boat was hit bu a series of short, steep waves (e.g. wash from a power boat). It also meant we could take the tension right off the winch cable for maintenance if needed.
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We used to have an Evolution 22 with a lifting dagger board on a little mechanical winch. It had a huge stainless bar (about 40mm diameter from memory!) which slid through a hole in each side of the top of the keel housing and through the top of the keel itself - i.e. into the housing, through the keel and out of the other side of the housing. It was quick and easy to fit and although we never got knocked down, it helped stopping the keel knocking against the housing when the boat was hit bu a series of short, steep waves (e.g. wash from a power boat). It also meant we could take the tension right off the winch cable for maintenance if needed.
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geoffatstanpit
Member
Re: Seal 28
I seem to have fetched up as the "technical librarian" of the Seal Sailing Association and as such I have most of the old John Baker drawings that still exist of the 22's and 28's. Those plus an open eye at rallies when the opportunity to look at the boats has presented itself, I've got what I think might be an idea how they're put together.
The 22 (of which I owned a Sinbad variant for many years) has a cast keel consisting of a thinnish (5cm) plate with a big wide (25cm) dollop on the bottom. The keel box and hull moulding in way of the keel is very substantial and although I have heard of damage to the after end of the slot on hitting the Needles wreck at full chat, I would think it unlikely that the dollop would bash its way right through and destroy the boat. On the other hand I don't know of any incident of a knockdown past 90 degrees in a 22.
The 28 on the other hand has a large cast iron keel with the drop keel passing through a hole in its centre. The keel box in the cabin doesn't have any holes or access in its sides but the top is removable to maintain the winch mechanism. From the drawings I have the keel is a parallel sided casting without the dollop on the bottom so it may be that a 28 on going a long way past 90 degrees might find its keel migrating. I don't believe it has ever happened though and 28s have found themselves as far away as New Zealand so weather must have been encountered and survived.
I've now got a Parker 21 and there's nothing I can see to effectively stop that keel (500lb) flying out through the deck just forrard of the mast if the boat were to get itself right upside down in short order. I do try not to let that happen. It goes very nicely the right way up.
Geoff
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I seem to have fetched up as the "technical librarian" of the Seal Sailing Association and as such I have most of the old John Baker drawings that still exist of the 22's and 28's. Those plus an open eye at rallies when the opportunity to look at the boats has presented itself, I've got what I think might be an idea how they're put together.
The 22 (of which I owned a Sinbad variant for many years) has a cast keel consisting of a thinnish (5cm) plate with a big wide (25cm) dollop on the bottom. The keel box and hull moulding in way of the keel is very substantial and although I have heard of damage to the after end of the slot on hitting the Needles wreck at full chat, I would think it unlikely that the dollop would bash its way right through and destroy the boat. On the other hand I don't know of any incident of a knockdown past 90 degrees in a 22.
The 28 on the other hand has a large cast iron keel with the drop keel passing through a hole in its centre. The keel box in the cabin doesn't have any holes or access in its sides but the top is removable to maintain the winch mechanism. From the drawings I have the keel is a parallel sided casting without the dollop on the bottom so it may be that a 28 on going a long way past 90 degrees might find its keel migrating. I don't believe it has ever happened though and 28s have found themselves as far away as New Zealand so weather must have been encountered and survived.
I've now got a Parker 21 and there's nothing I can see to effectively stop that keel (500lb) flying out through the deck just forrard of the mast if the boat were to get itself right upside down in short order. I do try not to let that happen. It goes very nicely the right way up.
Geoff
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wicked
Member
I have an Evolution 26 with an 800lb cast iron vertically lifting hydraulic keel. The rest of the ballast is bonded into the bottom of the boat like the Seal.
When the keel is down two struts bolt it into position so it's solid - effectively a fin-keeler. You can stand the boat on the keel up against a wall if you are that way inclined (always been too scared myself!).
Quite a good arrangement really - you get a boat that will float on wet grass with the keel up - and a fin-keeler with it down.
Dave.
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When the keel is down two struts bolt it into position so it's solid - effectively a fin-keeler. You can stand the boat on the keel up against a wall if you are that way inclined (always been too scared myself!).
Quite a good arrangement really - you get a boat that will float on wet grass with the keel up - and a fin-keeler with it down.
Dave.
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