[rocdoc22]

I'm looking at a St. Croix Jr. Crane to lift my outboard up to the rail.
What's the best way to mount the baseplate? Does one just use a good stainless steel screw or do you need a typical nut/bolt/washer? I'm not sure how the heck I would get under there to put a nut on. Should I be using some adhesive under the baseplate to make her watertight.
Never drilled into my new Jeanneau and am a wee bit nervous.
Thanks in advance.

 

[tomandchris]

Well, I think that the first thing you need to do is see what the manufacture of your product recommends. Somehow I don't think that screws are going to be the answer.

And, you can get to almost anywhere for backing plates and bolts, it is just a matter of taking things apart to get to most of them.

 

[Stu Jackson]

Why shouldn't screws work just fine? It all depends on where the base is located. If it is on a flat surface like mine is, screws are fine. If it's on a slightly inclined surface, screws may well work too. We just don't know. And even if it is an inclined surface, the screws would be in shear, which is what they are very good at. Like cam cleats for lines coming in horizontally. Only the PO knows, and I know he's asking, but he has to think about it.. Good idea about the RTFM part, too. Yes, the base should be sealed, use butyl tape.

 

[Gladrags1]

Just a comment: the main purpose of the base plate is to keep the crane from sliding out from the bottom. The pressure would be side to side. The amount of pressure is usually less than the typical 100# limit, much less. We are not looking at huge forces here. No backing plate is required and screws are just fine. The plate probably requires 4 which would be more than adequate. Size the screw by the diameter of the hole and the thickness of the fiberglass. The instructions undoubtedly tell you what size to use. Bolts would not be necessary. Yes, use butyl tape to seal.

Tod

 

[svHyLyte]

I'm looking at a St. Croix Jr. Crane to lift my outboard up to the rail.
What's the best way to mount the baseplate? Does one just use a good stainless steel screw or do you need a typical nut/bolt/washer? I'm not sure how the heck I would get under there to put a nut on. Should I be using some adhesive under the baseplate to make her watertight.
Never drilled into my new Jeanneau and am a wee bit nervous.
Thanks in advance.

Because of the induced loading, the base plate should be through bolted with a matching backing plate on the under side of the deck or at least large cut-washers, preferably doubled under each bolt. You will need caulking compound under the base plate to prevent moisture penetration in the deck/under deck space. Adhesive caulking is unnecessary. If the decking is not level, position the base plate so that the lift tube can be set vertical on the mounting pin. You might find the Forespare Nova Lift a better alternative than the St. Croix. See (click on) Nova Lift at Defender for details.

 

[chef2sail]

Because of the induced loading, the base plate should be through bolted with a matching backing plate on the under side of the deck or at least large cut-washers, preferably doubled under each bolt. You will need caulking compound under the base plate to prevent moisture penetration in the deck/under deck space. Adhesive caulking is unnecessary. If the decking is not level, position the base plate so that the lift tube can be set vertical on the mounting pin. You might find the Forespare Nova Lift a better alternative than the St. Croix. See (click on) Nova Lift at Defender for details.

Agree her. The loads are enough and will be substantial and a backing plate bolted with a front plate to spread them is the best way to go.

 

[Stu Jackson]

2 yes 2 no

Gee, OP, whaddya do now?

Good luck.

 

[MarkSF]

My experience with screws in fiberglass is that they tend to bind up and seize. If you must use screws, drill the holes out oversize, fill with epoxy, and then drill holes for the screws. However, I'd also agree that through-bolting with a backing plate is much better practice. Either way, you should over drill and fill with epoxy, to seal the core.

When I installed my Garhauer motor lift, I through bolted it but used large washers for backing, rather than make a plate, as they are out of sight and the loads aren't high.

I drank the koolaid about butyl tape and am regretting it now. Where I used it on my lifeline stanchions it has failed after one year. It also oozes out constantly, and looks awful as it attracts dirt. Back to Lifeseal and Sikaflec 291 for me.

 

[svHyLyte]

2 yes 2 no

Gee, OP, whaddya do now?

Good luck.

How many are rendered by professional registered structural engineers with 30+ years of experience?

 

[rocdoc22]

Thanks everyone. It seems logical that through bolting with large washers or a backing plate is the way to go. Just got to crawl up in there somehow.

Not decided yet on the Nova vs the St. Croix. I like the fact that I can take the St. Croix off easily and stow it.

 

[transmitterdan]

Nova Lift is also easy to remove and stow. But probably you won't need to do that very often. The Nova is pretty hard to beat.

 

[svHyLyte]

Thanks everyone. It seems logical that through bolting with large washers or a backing plate is the way to go. Just got to crawl up in there somehow.

Not decided yet on the Nova vs the St. Croix. I like the fact that I can take the St. Croix off easily and stow it.

The Nova lift is removable (the upper tube slides into the lower) and has the advantages of being somewhat easier to stow when unneeded because of its shape; and, having the line from the lift tackle lead internally through the tube(s) where it doesn't hamper handling the hoisted load and can easily be lead from an integral internal turning block to a winch.

FWIW...