How to move a boat?

I have a boat in a building The boat is about 4 inches off the ground at its lowest point. This is where the main supports are that hold the boat. This is where about 70% of the weight seems to be, It is also the main forward beam of the catamaran.

Then, there are a couple of supports on the aft beam bulkhead.

The boat is in a building and can't be raised higher (roof clearance).

It needs to be moved over to port by 2 to 3 feet. It also needs to be wheeled out of the building in a few months. To come out of the building, it has to wheel directly forward.

We had it blocked, but recently made some dollies. The wood buckled and broke that the dollies are made from. 2x4's gave out.

So... how can i move this boat 3' to port and then out of the building? It's a 50' catamaran.

 

Can you post some photos? It depends on the shape of the bottom of the hulls. You could simply reinforce the dollies with a piece of plate steel.

 

Use inflatable neoprene bags.

 

PVC schedule 80 pipe 3" if it is real heavy say 6 pieces the width of the hull, and pull and push it out of the garage
When one piece frees up out the rear relocate it at the front. Heavy loads can be easily moved this way if the ground is
reasonable level. Lay them lengthwise to push to one side. If you feed rope through them they can be kept straight. Old used steel pipe
may save you some money.

 

Do a search for machine dolly, or car dolly. There are lots of these relatively cheap in varying capacities. Some have built in hydraulic jacks to raise and lower the load. We move big boats on cradles all the time with these, although what we have look like they were made for moving industrial machinery 60 years ago and are too tall if you only have 4"-5". We use a hi-lo to lift the cradle onto the rollers, pull the boat and turn/steer it into position, or just reinforce the dollies you made with steel plate as suggested. You can always use six or eight of them if you need the capacity.

 

If the floor is cement, four jacks will do it too.

 

The problem with jacks is that when you try to move laterally the boat, we will have problems. Is that so ?.
I guess the site conditions are bad and that traditional methods, which anyone would think, are not usable.

 

Moving large objects can be challenging, but usually with some forethought and planning, you can get it done safely, though I've found, if you want a guarantee of success, come big or stay home is the answer.

Attached is a 100 ton mobile crane lifting me and a 2 ton boat, from a cradle to a trailer. Way over the top for what I needed, but very secure. I could have jacked the boat up, blocked it and backed the trailer under her, but the ground wasn't level and it was mostly sand, so I elected to spend $300 for my buddy Ed to show up with his massive crane. No guessing if it'll hold, no worries about things slipping or moving, etc., just a "snatch and set".

Of course this isn't going to work for you, but my point is come loaded for bear, even if on a squirrel hunt.

In your case, I wouldn't recommend rollers, as I've had this "get way" from me on several occasions. It's easy to move things this way, but difficult to control. Building some sort of wheeled platform, maybe under each contact point, much like that used on an automotive restoration sounds better. 3 heavy, full swivel casters on each so you can move in every direction.

 

The attached figure shows an example of how to put the boats afloat in one of the shipyard where I worked. A clear example of what snowbirder can not do.
Move an object with rollers, or the like, has the great advantage that the horizontal component of the forces involved is very small. So, with a pair of strings, you can perfectly control the movement. Control the inertia of the moving object is more difficult. Therefore, movements should be slow.

 

Seeing as you've got two or three moves to make assuming the boats headed back to the water one day & the H2O isn't just outside there's a couple of things to consider.
For the sideways move some fitted cradles at bulkheads could be good- in line with them some simple RHS(rectangular hollow section) rails fitted with brackets with gussets & welded on nuts with jacking bolts fitted("sharpen" 120 the bolt ends & index to some plates with drilled dimples so they don't squirrel around) lube up the rails with tallow & jack the screws till weights taken then pull sideways with chain come alongs- a chain link welded to the end of the rails is good for attachment & keeps the pull on the rail.
Really often the best way to move cats around is to support via underwing often flatter & much more convenient- of course care must be taken with cores & spreading loads in the interface, in this case a long support structure kind of like a box truss with diagonals or gussets can be built again out of RHS, can be modular & bolt up in sections, similar rails can be used to slide on, also if you need to road transport the structure can be designed to sit at the height you need on a low loader like is used for excavators, again simple screw jacks can be incorperated & even extensions to use hydraulic jacks on & also support with clearance while the trailer backs in, again some welded on chain links can serve as tie down points. It pays to invest a little, steel is cheap & strong & can save in the long term, 50' cats are exxy.

Jeff.

 

Jacks have wheels and a plate that rotates 360 degrees. We move large boats and heavy machinery with them. A method that also works well are greased boards and long levers. You can move anything like that.

 

There are many way to move things. How can snowbirder introduce all these wonderful artifacts "movers of things" in the enclosure in which he has his boat ?. I suppose that, being as intelligent as anyone, if he does not find the method is because he has some extra difficulty.

 

For example, a floor jack has a handle from which to pull. They are rolled into the building and under the boat. Planks are simply walked in, greased and slid under the boat. Dollies are carried by hand and installed under the boat.

 

Sorry, Gonzo, do not put in my text an intention that I have at all. What I mean is that normal solutions also will have happened to snowbirder and, if he is asking for a solution, it is because he needs something new.
It has happened several times that you insinuating that I say things that do not say. That's not an honest way because you want to take advantage of the shortcomings of my English.
Snowbirder if I said something wrong respect to you, I urge you to forgive me, was not at all my intention.

 

Thanks for the variety of ideas.

The floor is a terrible mess. It is a concrete pad with lots of pits, holes and drainage channels.

Wheels don't roll on it. We dropped some plywood under the dollies we made to even out the floor. It seemed like it would work for the lateral move until the 2x4s gave out. They bent like metal.

The most feasible ideas for this situation seem to be inflatable bags and dowels or pipes under the hull. Possibly a re design of the dollies as well.

Some photos to come..