Boat stands without blocking

[Mike OReilly]

As a few have said, it really depends on the boat. Some heavily built boats, or some that are quite light, can probably use this approach without too much fear. But the point is, hulls are not designed to take this kind of focused force.

Distributing the load is certainly a better idea. Lifting straps do this quite effectively. Point supports like jackstands — not so much.

It is certainly possible to shift a boat on its blocking. I’ve lifted the ends of my 15 ton boat using a 20-ton bottle jack such that I could change the blocking. The boat was in jackstands, so every move was slow and tedious, with every couple of cm shift requiring stand adjustments. But it can be done.

If you’re going to try this, my advice is go very slowly. And keep an escape route clear in case you have to run.

Far better and safer to simple do the work up to the blocking, then have the yard lift the boat, reblock, and do the remainder.

[Fore and Aft]

I have seen a lightly built foam sandwich race yacht end up with four crushed areas from jack stands. It was a late Friday afternoon slipping and the travel lift operator put the yacht down without checking that all the weight was on the keel. We came in Monday morning and you could clearly see the jack stand pads had sunk into the hull.
Cheers