Lift 4600lb boat 5"

[kristian]

Our Shields is on a trailer, and the keel sits in at the bottom of a narrow U Channel, about 12" wide and 4 deep. Take a look at shields88.blogspot.com for any number of boring photos of the keel.

Im trying to work on the keel, and need to reach the underside, which is pretty much impossible while the boats on it. I would like to put 2 4x4 wood blocks under the keel, above the trailer axles. This would give me enough clearance to prep fair and paint.

How do I do it? I want to lift in on the crane like usual, but unfortunately my boat is blocked in by others, and the yard crew is off for a few weeks.

Would it be possible to lift the boat using boatstands, one screw at a time? Is this really foolish to even think about or would it work. Other ideas?

Thanks,
Kristian

EDIT changed jackstands to boatstands

[Figment]

Car jack under the keel. Adjust the jackstands as you go.

[Peter]

On a smaller lighter boat I jacked up the trailer, blocked it, put stands under the boat, then lowered the trailer.

Lifting it with the trailer gives you a very secure lifting base. Might work on the Shields...

[Hirilondë]

I lifted my 6500 lb Renegade off the keel using jack stands alone (6 reg ones and 2 V bow ones). Kind of tedious, but worked.

[Tim]

If you lift with jackstands, just be sure the hull can take the strain, and/or that the stands are located at bulkhead locations. A boat with a thin hull like a Shields could distort easily once you start supporting the weight of the boat with stands alone.

For your Shields, I think Peter has the right suggestion: lift the whole trailer, support the boat with external stands, and lower the trailer. A car jack works well, but your keel is probably not accessible from beneath because of a full-length support platform, so the jack wouldn't work in your case.

[Quetzalsailor]

Dad made keel jacks for his 7500lb Morgan 27. (Gawd knows why, but he made the jackstands, too.) The keel jacks are lengths of 3" x 4" steel tubing with a jackscrew at one end (I think; they're in my barn; I never dared use them). The yard would block the boat normally, using his jackstands and their wood keelblocks. He'd place his keeljacks transversely under the keel, block one end of each and jack the other, then snug up on the jackstands. Clearly, one would have to reset the blocks under the keeljacks as they would become more tipped the higher they went.

With this method, you don't lift the boat with point loads at the jackstands, but you also don't have access to the whole of the bottom of the keel. Normally, the jackstands aren't taking but some small percentage of the weight of the boat; they're stabilizing the beastie balancing on the keel and resisting windload.

Most yards I've heard of get really antsy and negative about us amateurs adjusting our jackstands. They consider the risk too great for them and their adjacent customers.

It's easy enough to control fouling on the bottom of the keel; find a sandy spot on a quiet day and run 'er aground.

[kristian]

Once the yard reopens in Jan, I think I'll try and get the boat out to the crane and just lift the boat.

If thats not possible I've got a few weeks to try and figure out how to get the boat up by jacking the trailer. The backs easy, as the boat overhangs the trailer by about 10' in back, and the aft bulkhead will be easy to block. The front, not so much. Any blocking would have to come from between the beams of the trailer, and I don't know of any boatstands narrow enough (for obvious reason) to fit there.

The point beind this is to sand and paint the bottom of the keel, which is pretty rough after 40 yrs.

Thanks for all the great advice
Kristian

[kristian]

All,

Ended up waiting until the boat was outside and the yard used their forklift to bring the boat up while we put wood blocks under. This was easy as we have a single point lift.

http://bp1.blogger.com/_ifoPhvg9GMo/R_Q ... G_2355.JPG

Cheers,
Kristian