I noticed on the hull(1980) where the keel bolts to the hull(on the outside) that there seems to be a flat spot at the back end of the keel where it is flared into the hull. It almost looks like the hull is pushed up(a inch or so) aft of the keel about a foot and then slopes down and slopes to the stern.I don't know if thats the way it should .The boat is on a cradle and I am wondering if there should be some flex in the hull or there is other problems? Thanks Allan
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John
Bulk of support on keel?
The hull is formed fairly smooth at the factory. As described, this flat spot does not sound very good. If I understand it correctly, it appears the aft end of the keel has pushed the hull up to cause the flat spot. When a boat is in a cradle or supported by jackstands, the hull and keel should have the support loads relatively evenly distributed. The boat should not have nearly all it's weight supported by the keel for an extended period of time. Perhaps the yard didn't adjust the jack stands for the stern to take enough of the load, or, perhaps the stands may have setteled some. I'd suggest adjsuting the aft stands to take more of the load and see if the deformed part springs back. Look inside the boat at the grid and see if there are any stress cracks in the gel coat and also look in the area where the grid is bonded to the hull to see if there is any separation.
The hull is formed fairly smooth at the factory. As described, this flat spot does not sound very good. If I understand it correctly, it appears the aft end of the keel has pushed the hull up to cause the flat spot. When a boat is in a cradle or supported by jackstands, the hull and keel should have the support loads relatively evenly distributed. The boat should not have nearly all it's weight supported by the keel for an extended period of time. Perhaps the yard didn't adjust the jack stands for the stern to take enough of the load, or, perhaps the stands may have setteled some. I'd suggest adjsuting the aft stands to take more of the load and see if the deformed part springs back. Look inside the boat at the grid and see if there are any stress cracks in the gel coat and also look in the area where the grid is bonded to the hull to see if there is any separation.
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Ken Palmer
Didn't know that
I had never heard that you are not supposed to support the boat's full weight on the keel. I thought that the cradle jack-stands are used mainly for support from tipping, not to hold the weight of the boat. Ken Palmer, S/V Liberty
I had never heard that you are not supposed to support the boat's full weight on the keel. I thought that the cradle jack-stands are used mainly for support from tipping, not to hold the weight of the boat. Ken Palmer, S/V Liberty
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Been there
Most cruising boats CAN be supported by keel
As Ken Palmer points out, jack stands serve more to keep the boat from tipping than to support it. Even with chains holding them, they tend to relax outwards. It is really the keel that takes the bulk of the boat's weight, in most setups. If you doubt this, stay on a boat on the hard during a windstorm, and observe it rock back and forth in its jackstands. (Racy designs with deep fin keels may need cradles or trailers designed to take more weight off the keel.) The stresses from holding the boat up are small compared to the stresses of a hard grounding, where the full weight of the boat may be shoved against a keel suddenly stopped dead in the water by an unseen obstruction, or where the boat may be pounded up and down on its keel, by wave action. I would not buy a cruising boat whose hull deflects merely from holding it up. Not that particular boat, nor any sister boat, unless I had explanation of what was flawed about that boat and why that flaw is not present in sister boats.
As Ken Palmer points out, jack stands serve more to keep the boat from tipping than to support it. Even with chains holding them, they tend to relax outwards. It is really the keel that takes the bulk of the boat's weight, in most setups. If you doubt this, stay on a boat on the hard during a windstorm, and observe it rock back and forth in its jackstands. (Racy designs with deep fin keels may need cradles or trailers designed to take more weight off the keel.) The stresses from holding the boat up are small compared to the stresses of a hard grounding, where the full weight of the boat may be shoved against a keel suddenly stopped dead in the water by an unseen obstruction, or where the boat may be pounded up and down on its keel, by wave action. I would not buy a cruising boat whose hull deflects merely from holding it up. Not that particular boat, nor any sister boat, unless I had explanation of what was flawed about that boat and why that flaw is not present in sister boats.
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Terry Arnold
H33 hull keel lines
I have looked in my photos for a comparative view of my boat, a 1979 H33 shoal draft. Not very good but here is a link to a photo of the area. http://msnhomepages.talkcity.com/HobbyCt/tgarnold/keel.jpg The centerline should fair upwards from the aft end of the keel. I would check the inside bilge area very closely for signs of structural distress. I think that this is probably the thickest laid up (and therefore strongest) portion of the boat so that if it really is flattened, you would suspect something like repetitive pounding in a grounding.
I have looked in my photos for a comparative view of my boat, a 1979 H33 shoal draft. Not very good but here is a link to a photo of the area. http://msnhomepages.talkcity.com/HobbyCt/tgarnold/keel.jpg The centerline should fair upwards from the aft end of the keel. I would check the inside bilge area very closely for signs of structural distress. I think that this is probably the thickest laid up (and therefore strongest) portion of the boat so that if it really is flattened, you would suspect something like repetitive pounding in a grounding.
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Bob E.
Keel support
I agree that most boats should be able to support the full weight of the boat on the keel. One boat that I have heard from reliable sources that cannot be fully supported on the keel is the 1970's C&C 27. Check out any large marina during the winter, and you will probably see some boats where the pads aren't snugged up against the hull all the way around. Nevertheless, I make sure that my boat, a H30G, has the weight shared by the keel and the cradle pads. You have to be careful not to overdo it, or you can "dimple" the hull.
I agree that most boats should be able to support the full weight of the boat on the keel. One boat that I have heard from reliable sources that cannot be fully supported on the keel is the 1970's C&C 27. Check out any large marina during the winter, and you will probably see some boats where the pads aren't snugged up against the hull all the way around. Nevertheless, I make sure that my boat, a H30G, has the weight shared by the keel and the cradle pads. You have to be careful not to overdo it, or you can "dimple" the hull.
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Ken Palmer
Dimple is an understatement
I saw a Hunter H33 that had one of it's cradle pads up too high. When the marina crew set her in for the winter, that high pad caused oil-canning in an area about 3 feet in diameter. The area was inspected by a marine surveyor, and it was determined that there was no damage to the structure. This was 14 years ago, and the boat is still solid and seaworthy. Ken Palmer, S/V Liberty
I saw a Hunter H33 that had one of it's cradle pads up too high. When the marina crew set her in for the winter, that high pad caused oil-canning in an area about 3 feet in diameter. The area was inspected by a marine surveyor, and it was determined that there was no damage to the structure. This was 14 years ago, and the boat is still solid and seaworthy. Ken Palmer, S/V Liberty
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Sam Lust
Hull divot
Allan- I have a decent picture of what I think is the area you describe on my '83 33. A straight profile shot. The weight of the boat rests on the keel with the pads only keeping it from falling over. I see no evidence of depression. However, the yard did put the pads up too far and cracked some of the inner tabbing when they set it down on the cradle. Now I personaly supervise the work and run the pads up myself. Jim Bohart has stated here that the boat's weight should be on the keel. If you want I can scan and e-mail the picture. samlust@monmouth.com
Allan- I have a decent picture of what I think is the area you describe on my '83 33. A straight profile shot. The weight of the boat rests on the keel with the pads only keeping it from falling over. I see no evidence of depression. However, the yard did put the pads up too far and cracked some of the inner tabbing when they set it down on the cradle. Now I personaly supervise the work and run the pads up myself. Jim Bohart has stated here that the boat's weight should be on the keel. If you want I can scan and e-mail the picture. samlust@monmouth.com
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Steve Donahue
Have we missed the point here?
If I understand, you're asking about a small indentation (3"inches round?) on the bottom of the hull next to the keel - aft. I have it on my '83, and just looked at 2 other Hunter 34's, and they have it. On mine, the epoxy/fiberglass is chipping off and there is metal (flair from keel?) underneath. I'm going to remove all the old epoxy and resurface this spot, but the indentation seems normal.
If I understand, you're asking about a small indentation (3"inches round?) on the bottom of the hull next to the keel - aft. I have it on my '83, and just looked at 2 other Hunter 34's, and they have it. On mine, the epoxy/fiberglass is chipping off and there is metal (flair from keel?) underneath. I'm going to remove all the old epoxy and resurface this spot, but the indentation seems normal.
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