Jacking up a yacht

[Roach1948]

I am getting the outside of the yacht ready for launch and need to prime and antifoul the hull. She is currently laying on wooden sleepers, and supported by wooden shores. I would like to move the sleepers along the bottom, so that I can fair the base of the keel and apply primer and antifoul etc.

Can I do this using a car trolley jack and have friends reposition the shores around or is this foolhardy? I would be very interested in anybody that has done this before and can give me tips.

I am not in a boatyard to no crane available. Her current set-up below.

PS She weighs 3 tons!

 

[savageseadog]

Dig!

 

[fireball]

With no side bars as you jack up the pressure on the support struts at the side will go and they'll probably fall over ... leaving the boat unsupported and she's likely to fall over. /forums/images/graemlins/frown.gif

 

[WayneS]

What about building a gantry over her with scaffold poles etc and and hang her there with strops.

W

 

[fluffc]

3 Tons of boat supported by a 'scaffold' - you are joking aren't you??

 

[WayneS]

Well, a reputable boat transport company on the south coast lifted my 2.5ton boat onto a trailer using that method so I have to assume that it must be possible somehow.

Wayne

 

[michael_w]

It can be done. As a kid I remember seeing boats moved on greasy ways at Port Hamble. Miles of wire rigged through blocks all over the yard ending up conected to an astmahtic tractor, lots of hand signals and bad language. Dunno how they did it though.

 

[kengill]

Rent a mobile crane. There are some very experienced boat movers who can do the job of moving it around for you with blocks etc but I would have thought the most safe method was to lift it and do it while lifted.

Why not do part of the bottom when it is lifted on oo the transport at the end - over their lunch hour perhaps?

and the remaining bits while its in the slings just before launch. Minimum handling equals maximum safety

and minimum cost!!

/forums/images/graemlins/smile.gif /forums/images/graemlins/smile.gif /forums/images/graemlins/smile.gif

 

[steveallan]

I would'nt worry about the bottom it will be cleaned by the shingle every time you leave the Deban at or near low water. water.

 

[simonfraser]

foolhardy i'd say, if - no - when that lot falls over you'll kill some one
only do it if you have a fail safe way of supporting the boat sideways
perhaps you can hire a proper boat cradle?

 

[Roach1948]

Thanks, I think this is the safest suggestion. I will do it when they move her to the coast and hopefully the paint dries off when on the lorry!

 

[[3889]]

A yard near me has no crane or hoist and uses trolley jacks either end of under keel timber baulks to lift boats off / on trailers. They chock the boats with 45 gal drums and wedges between the hull and baulks. I don't lift out there but I have never heard of an accident and this method has been used by them for many years. 3 tonnes would be about the largest boat I have seen there but the owner assured me my last 3.6 tonne fin keler would be perfectly safe, but I bottled it.

 

[Clyde_Wanderer]

Why not get lengths of scaffold poles that are about 3-4ft longer than the height of boat from ground to toe rail, get someone with a JCB in to sink the poles 2-3ft into ground, say one at each quarter, and one at each side abeam, then fix outward and downward slanting diagonal braces to each vertical pole to stop them from falling outward if any force comes against them.
Once you then start jacking up, the boat will slide up along the vertical poles and cant tilt side to side.
Yoy could even take a pole horizantly on the ground , from the bottom of a diagonal on one side of boat to the diagonal brace on the other side to stop diagonal braces spreading at ground level.
Will do you a diagram/drawing if you want.

 

[sarabande]

Not joking. Properly triangulated, ordinary builders scaffolding will lift that easily.

3 sets of "goalposts", lots of cross-bracing, and ratchet straps (5 ton each) lifted my YW Peoples Boat (4 tons) easily.

 

[William_H]

Hello Roach from the photo your props do look a bit too precarious to permit jacking of the keel.
For the next winter lay up I would suggest positively placed side verticals (not so much props).
A plank or steel RSJ under the keel with verticals attached which can be joined across the top (or braced to the bottom plank) will keep the boat vertical. This arrangement should be at least duplicated.
The braced verticals up beyond the gunwhale can be lashed to things like sheet winches or chain plates.
you would then be able to fairly safely jack up one end of the keel at a time.
As it is now your best bet might be to dig under at least the keel leading edge to enable fairing and painting. But don't dig too much or you could be in trouble. good luck with the relaunch olewill

 

[cliffordpope]

Your problem is the props will all fall over the moment you lift the hull. You need the traditional method of a pair of big oil drums and some wooden wedges. That way even though you lift the hull an inch or so, the drums stay in place and you lower the boat back onto them after you have moved the sleeper.

Ive done it singlehanded with a 2 1/2 tonner

 

[bluemoongaffer]

I hired a simple gantry ("I" beam on legs with wheels) that was about 8 ft wide and 10ft high from a lifting company. Quite easy to put up (if a little heavy). Then I used straps and a winch to lift all or part of the boat as needed. I can't remember the rated lifting capacity though. Yellow pages should find you something similar. Cost about £100 for a week. (I used Conford lifting in Wimbledon)

 

[Slowtack]

Check mags last couple of years for article on simple underkeel lifting system using reversing hardwood wedges and threaded bar.
You will need at least 4 braced adjustable hull props (eg acrows) to keep pace with the lifting though.

 

[Mudplugger]

Re: Query.... 1) Can you get a crane anywhere near? Super guy, operates out of Needham Market and does a lot of boat lifts around the woodbridge area. Probably get in touch with him from the yards on the Deben. (he lifted mine 8t @ 30' for £200) 2) you should not have a problem if you use Scaffolding and Pulley blocks!.... particularly as advised in earlier post. 3) if you use 200l oil drums and wedges, would suggest 3 each side and make sure that they can't move sideway's! by using stakes. and if lifting with trolley jack, lift a couple of inches at a time and move wedges.....don't be greedy! and you will find it relatively easy. By the way, if you lift the back, then go and lift the front and viccy versa. hth