Cradle or shoring?

[Norman_E]

After seeing Clyde Wanderer's thread and the way that yachts were shored up with just a few props and no cross bracing its hardly surprising that one blew over, and very bad luck to Clyde Wanderer that his boat was the innocent victim.

I am however a bit puzzled by all the criticism levelled at shoring because where I keep my boat at least half the boats on the hard each winter are shored. I have had mine shored every year that it has been on the hard except the last time, when I rented a cradle so that there were less parts of the hull that could not be scraped or anti-fouled. My experience was that in the cradle the boat vibrated and shook in a strong wind, and the comparatively narrow base of the cradle inspired little confidence. I asked for some shores to to be added to control the vibration.

The yard has no policy of requiring masts to be taken down, and stores about 600 boats on the hard. The only mishap I have heard about was when a large steel framed shed blew down in a storm and damaged about five boats, but no boat on shores or cradles has fallen.

I am not happy about using a cradle that puts a 45 foot boat onto something about 10 feet long, and the yard seem to agree as they always add bow and stern props, and sometimes lateral props as well.

As this picture of my boat shows the yard cross brace the shores, and if you look at the boat on the left you will see that they have added some extra props to a boat that is on a cradle.

 

[Clyde_Wanderer]

Norman there is cradles and there is cradles, what that boat on the left is on I would not call a cradle but a stand.
My reckoning is that a cradle should be much wider at the base/footprint than the beam of the boat like my cradle (see previous post on shoring)
Of course a stand like that also needs pit props because of its narrow width.
Two transit legs welded attached to the base of it and extending out 3ft on each side would make it much more stable.
I am thinking of resetting the props on mine to sit higher on the hull, and the base will still be plenty wide.
Even after the big boat pushed mine down and towards sb side she still sat secure in the cradle without any damage to the cradle or without it moving.
C_W

 

[NormanS]

My (home made) cradle is remarkably similar in design to CW's, with a broad base, six legs, all at approx right angles to the part of the hull where the pads touch. Although my boat has a comparatively long keel, I also put in a shore forward. It is important that most of the weight of the boat rests on the cradle.

As it happens, the yard where my boat winters has a policy of all cradles, but I wouldn't have it any other way.

A boat with a short keel is particularly vulnerable to "pirouetting", and a good cradle will prevent that happening.

 

[Spyro]

Sorry Norman E but if I had to choose I'd rather have a cradle than the shores that you have. Of course if I had a 45ft boat I'd want some extra props if the cradle was only 10ft long.
The yard where I'm laid up provide extremely strong cradles and provide extra shores even on my 32footer.
I know you say the yard has never had a problem but those props look woefully inadequate for a boat that size.

 

[Norman_E]

Yours looks good to me, but if you look at my picture you can see that the cradles at Yachtmarine are narrower than the boats, and are designed to enable the "trolley" that is just visible in my picture to manoeuvre boats into position. I don't think them very suitable to store a boat on all winter, even though the yard do try to get you to hire one I still prefer the props, especially as its hit and miss whether the cradles go exactly under the internal bracing of the hull. When the yard men put up shores, they tap the hull with hammers to determine where the cross bracings are.

 

[chinita]

I had the worst of both worlds in an expensive South Coast Yard.

Yacht shored up with skanky old timbers but had to pay £20.00 per month + VAT 'cradle hire'.

However, it did not fall over

 

[Babylon]

I prefer a spread of shore-props

I once tied my large and vigourous dog's lead to someone's shore-prop while I went aboard... wasn't to know there was a bitch on heat not far away...

However, now that my local yard has gone over largely to cradles, I've noticed that the aft-most pads distort the hull in the region of the companionway steps, with the result that the steps are squeezed by the surrounding structural parts making them difficult to remove and replace whilst in the cradle. I also noticed a de-bonding from the hull at the base of a usually hidden part of a bulkhead, although I cannot be completely certain that this resulted directly from the use of the cradle.

A hull is designed to be supported evenly by water most of the time. Subjecting it to just four localised pressure-points for a period ashore must surely put deleterious strains on it and the internal structural parts. A spread of several shore-props down each side, as well as under the bow and under the counter, all properly secured by a lattice of cross-members, must surely be preferred.

 

[Poignard]

I once tied my large and vigourous dog's lead to someone's shore-prop while I went aboard... wasn't to know there was a bitch on heat not far away...

I'm just thinking of what the owner (of the boat) would write on the insurance claim form.

 

[bluerm166]

Shoring

We may have gone over the top,but Norman,your boat is over twice the size of ours,if sitting firmly on the ground,so I find the arrangement fairly shocking.Is this in the Jeanneau manual ?
Let's hope the yard continue to employ luck ,as well as the expert nailer,and have forward stocks of driftwood.

 

[Bodach na mara]

I have a preference for props as they have been used to support boats since Noah was a boy. Props could be located at bulkheads or frames and at least four were used per side on my 30 foor ex-6 metre. Cross-bracing was never seen.

With my next boat (a Primrose designed Commando motor sailer) the yard that I usually laid up in used cradles and I always had a problem in getting them to position the boat so that the supports were at a bulkhead. They usually got at least one pair propping against the hull mid-way between bulkheads and sometimes both pairs were positioned in this way. I then used to supplement the cradle props with lumps of tree correctly located. Fortunately this was in a shed.

With Wight Dawn, I went back to that same yard at Renfrew (no longer there.) Again they used a cradle with 4 props but supplemented it with 4 "pit props." And the mast was down. Due to problems in launching and recovery connected to the strong tide and the boat's tendency to prop-run when you apply reverse gear, I did not return there but went to Ardrossan, where a 6-prop cradle was used. My boat was OK following the gale in January 1999, but five others blew over, the cradle props of several punching holes in their hulls. In each case the mast was still up, as was mine. I was just lucky.

Where I am now (at Largs) cradles are used if you have one. Otherwise they shore up the boat with props and use plenty per side. It has gone up over the years from four to five or even six per side, all cross-braced, and at least some of them are near bulkheads. If you are in a cradle, the mast stays up. In props, the mast comes down. As I said before, all the boats at Ardrossan that blew over had masts up (and there were several blew over at Largs in that gale as well) thus I would rather be on the tried-and-tested props with the mast down than in a cradle with it up.

 

[PetiteFleur]

My Moody 33 is in a cradle with 3 supports per side, with a base width of about 10½'. Surely the idea is to let the keel rest on the cradle base/ground and the side supports are just wound in to prevent the boat moving - they should take very little weight. This is how my yard sets up the boats. Sometimes they add a shore under the bows on some boats.

 

[Bosun Higgs]

MY boat is in a steel cradle with a 10ft base. It has 2 pads each side cross braced with scaffold poles. It has individual acrow supports bow and stern. And it has 2 cross braced wooden shores each side as well. And the mast down.

It doesnt move

 

[Norman_E]

We may have gone over the top,but Norman,your boat is over twice the size of ours,if sitting firmly on the ground,so I find the arrangement fairly shocking.Is this in the Jeanneau manual ?
Let's hope the yard continue to employ luck ,as well as the expert nailer,and have forward stocks of driftwood.

I don't think its luck at all. My boat has been kept over winter at Yachtmarine since I bought it close on 6 years ago. In that time I reckon that the workers there have put two or three thousand boats ranging from small yachts up to large motorboats and gulets on wooden props, without mishap. As for the Jeanneau manual, the only one I have says nothing on the subject.

 

[Robin]

We always had our boats in a proper cradle, with the weight of the boat taken on the keel and the cradle supports not taking much weight at all, just tensioned enough to prevent vibration shaking the pads out. We also had a shore at the bow, another at the stern and two more each side in between the cradle supports. Our boats were ashore with masts up but sails off, but some left them on, the only rule was that all fin keel boats had proper cradles, most of which the yard provided for a weekly fee.

Our new boat in the USA is stored ashore pending our return and in a hurricane area so our insurance insist on extra care. All supports (being a mobo ours are individual accrow type stands, 4 each side and props fore and aft also) must be chained together under the boat to prevent movement. The boat sits on hard wood blocks and like a sailboat cradle the stands are there for location rather than load bearing, our boat weghs in at around 17 tons. There is then a system of straps and ground screws brought into play in the event of a hurricane being forecast.

IMO the boat weight must always be on the centreline/keel not on small area cradle pads or shores which should only ever be for location and balance not load bearing.

 

[chubby]

Does the nature of the ground have an influence? If hard concrete maybe a cradle but at my yard the ground is compacted earth / hardcore type stuff and they use shores which seem to bed into the ground nicely but might not do so on concrete?

 

[Robin]

Shores on a hard surface are kept in place by wedges at their base, the worse case is on crumbly or soft ground when they will have no constant support. A properly designed cradle will stay put and can be stabilised further by the use of wedges to compensate for a non -level piece of ground. Over the years our boats have been stored on both hard concrete loose surfaces, in one case made of broken pottery pieces from a nearby tile factory, but a cradle was fine every time, but as mentioned before also with additional wood shores.

 

[Norman_E]

Perhaps I should make it clear that the keel of my boat is not hanging in mid air, but on wooden blocks, and that most of the weight of the boat is in fact on the keel. When the props are put up you can hear the hammer sound change as the wedges are banged tight and the props take some of the load.

 

[Clyde_Wanderer]

IMO the boat weight must always be on the centreline/keel not on small area cradle pads or shores which should only ever be for location and balance not load bearing.

Totally agree.

This ariel pic shows exactly how broad my cradle is at ground level, this is how cradles should be.

C_W

 

[Captain Haddock]

I've had both and I'll take a cradle any time. I prefer steel over wooden shores to hold my boat over winter.

 

[Seajet]

My Moody 33 is in a cradle with 3 supports per side, with a base width of about 10½'. Surely the idea is to let the keel rest on the cradle base/ground and the side supports are just wound in to prevent the boat moving - they should take very little weight. This is how my yard sets up the boats. Sometimes they add a shore under the bows on some boats.

Spot on, after seeing the carnage resulting from the 1987 Hurricane - and I would understand people not there to think 'Hurricane' an exaggeration, but I promise it's not, boats ashore blown over like domino's, those on moorings blown ashore with keels torn off etc.

A cradle every time, as long as it's properly engineered, and has large support pads- but agreeing completely the hull of a fin keeler should have the weight resting on the keel, not the side steadies.

There is the other point that a friends' boat has been damaged by a boatyard berk hammering in a wooden wedge above a guesstimated wooden prop too hard - this would be unlikely to happen with a decent cradle & 'acro' style buttress thread steadies.