Boats on lifts

[higgs]

I have always operated on the premise that a keel boat is stored with the weight on the keel to avoid damage, yet, I have seen small keel boats in Florida stored on lifts with out supporting the keels. Are these sailors just ignoring this bit of storage practice at the peril of their boats?

 

[Bill1565]

Yup. They are. Many of my neighbors were not boaters before they retred and moved to Florida. Had good credit. Bought boats. Mostly Sea Rays, but some sailboats also. Presto, call them "Captain".

 

[bffatcat]

storing a keel boat

The keel should always be supported. No hanging or you could have problems

 

[Nodak7]

I have always operated on the premise that a keel boat is stored with the weight on the keel to avoid damage, yet, I have seen small keel boats in Florida stored on lifts with out supporting the keels. Are these sailors just ignoring this bit of storage practice at the peril of their boats?

Higgs it is interesting that you posted this. I have been told the same thing. Weight on the keel! However, I have observed many large racing boats with those deep bulb keels stored with the keel and bulb just hanging down unsupported while the boat sets on stands. These are expensive boats and I would imagine that the owners would not intensionally damage them by improper storage. So I must assume that they are either constructed differently or there are a number of "uninformed" owners. Am I missing something here? Are they constructed differently?

 

[Benny17441]

The problem is dependant on the bunks surface. When the boat is in the water the keel is hanging free from the hull and it weighs the same as when it is out of the water. The difference is that in the water the weight is distributed along the wetted surface of the hull and when sitting in bunks it is just distributed among an area equal to the surface of the bunks. If the bunks are large enough and cover an adequate surface along the curves of the hull there is no problem. The thickness of the hulls in smaller boats are not that much less than larger ones and can carry their lighter keels with less support. I too have heard that before but there is no concrete evidence to support it and the number of boats on lifts down here would tend to dispute it.

 

[Bill1565]

e=Nodak7;970749] I have observed many large racing boats with those deep bulb keels stored with the keel and bulb just hanging down unsupported while the boat sets on stands. [/quote]

I bet if you looked closely you would find pieces of 6x6 or railroad ties under the bulbs on these boats.

 

[Nodak7]

e=Nodak7;970749] I have observed many large racing boats with those deep bulb keels stored with the keel and bulb just hanging down unsupported while the boat sets on stands.

I bet if you looked closely you would find pieces of 6x6 or railroad ties under the bulbs on these boats.[/QUOTE]

Not a bit Bill. I looked very closely! Nothing under the keel! Matter of fact I was so impressed that I took a picture. I have attached it. Look closely and you will see no support under the keel. Since that time I have seen a few more in yards with suspended, unsupported, keels. Just a few weeks ago in the Annapolis Boat Yard I saw two.

 

[Joe]

For years, Roy Disney's famous sled, "Pyewacket", was stored in the yard next to my Marina. It is 70+ feet long and has a very long, bladed keel with a huge bulb, which was unsupported. The reason being obvious when you look at it... so boat design is important, (obvious, I know).

I hope we can get some more expert input. One thought tells me that all the weight on the few square inches of block the bolted keel sits on is pushing up into the hull and could distort it. The other says all that weight hanging down could do the same thing .... and what about keels molded into the hull with the ballast encased?

 

[Nodak7]

I hope we can get some more expert input. One thought tells me that all the weight on the few square inches of block the bolted keel sits on is pushing up into the hull and could distort it. The other says all that weight hanging down could do the same thing .... and what about keels molded into the hull with the ballast incased?

LOL Joe I am sure that we have plenty of experts in this Forum that can give us the reason! I am sitting here waiting with baited breath to hear what that may be!

 

[Benny17441]

It is obvious the keel/hull joint is up to the task of holding the keel suspended. Besides the weight of the keel it is also capable of holding the added forces generated when the boat is under sail. That leaves the hull to be concerned about. We have all heard of oil canning or dimples created in the hull by fiberglass bending. Fiberglass is flexible but there are limits about how far and how many cycles of bending it can withstand before structural deformation occurs. Depending on the location and the surface area of the bunks or pads some degree of bending can be anticipated. It just so happens that when a boat is placed on a craddle or lift the cycles of bending are limited to a single ocurrence. It has been my experience that most boat hulls can experience safely hundreds if not thousands incidents of bending so that should make it safe to suspend on a lift but not necessarily the best practice. Sitting the keel on the hard for seasonal haulouts may avoid the bending stresses on the hull but that is not really an option on a lift. In conclusion I would say that the additional wear and tear placed on a boat by supending it in a lift is a reasonable and justifiable tradeoff for the convenience of having it readily available to go without having to paint or clean the bottom or having it constantly slaming against dock pilings in high transit areas. After all a boat has to be used to be enjoyed and we chip away in different forms at its usefull life every time we take her out. The convenience to take her out is an integral part of the experience. I don't have a lift as I cannot justify the cost associated with one rated for 8-10 tons plus we need to have bottom paint as we sometimes relocate the boat for months at a time.

 

[Nom De Guerre]

Some boat can't be stored with the majority of their weight borne by the keels (swing keels, deep fin w/bulb keels, etc.). These boats have to be stored with the majority of their weight borne by strategically-placed pads/bunks, which work in concert with the interior hull support/structures.

You'll notice in Nodak7's picture that the boat isn't supported by four or six 1' square pads randomly distributed around the hull, but rather it is supported by two bunks that spread the weight across the entire width of the hull fore and aft. I suspect that these two bunks are strategically positioned to align with internal weight-distributing bulkheads or hull grids.

This is just another way to solve the load-bearing design problem and there isn't anything inherently wrong with it.

 

[higgs]

Nodak's photo shows a boat with the wieght supported by a couple of 6 inch wid bunks. Perhaps that hull can withstand that.

Joe: I have a boat with an encapsulated keel and, as far as I am concerned, there is no difference. For storage the wieght goes on the keel and the pads stop the boat from falling over.

 

[PaulK]

Spreading the weight over the bunks in the photo looks like it is sufficient. Perhaps the keel includes a tounge that extends to the bunks as well. The problem is not so much the weight of the keel being supported by the hull, but the supports punching holes in the hull if the weight isn't spread out sufficiently.

 

[Chris Patterson]

That cradle is little different from the travel lift slings. It's easy to see why normal jack stands would not support the boat well, even going so far as to punching holes in it.
I very recently went to look at a Compac Yacht, and upon entering, saw that the keel had been literally pushed up through the hull. The jack stands had settled on the very unsound earth, whereas the keel blocking had not. Must have been one helluva balancing act for the jacks to have settled simultaneously without the boat toppling.
It was actually a pretty gruesome scene..