Lifting davit on a rib

[Stevie J]

Hi All,

Here's a hypothetical question at the moment...

Could a lifting davit be fitted to a rib?

Swinging arm (90 deg), up to 50m of cable, weight limit 20 Kg upwards (eg dive kit).

Willing to entertain any ideas.

Cheers Stevie

[Nasher]

I've looked at this one myself.

I designed a Stainless steel 'arm' which was the same shape as half my A frame and was pivoted to it in two places so that it could be swung out and used as a crane with a small trailer winch attached to the bottom.

I never actually built it, but couldn't see any reason why it wouldn't work.

I suppose the answer to your question is that anything is possible with a bit of imagination.

Nasher.

[diver 1]

Perhaps not so user friendly but you're lifting capability would be greatly improved if you could rig up off the stern to lift inline with the vessel rather than across the vessel. You'll be trying to sink the stern or tip the boat backwards rather than roll her then. Lifting heavy loads over the side at sea can rapidly lead to unpleasant situations if poor conditions / beam sea. Also think of quick payout / release mechanism if you suddenly realise its not going to work out!!

[Poly]

Anything here of use?

http://www.rib.net/forum/f30/rib-wit...e-44608-2.html

[Stevie J]

Strangely, one technical difficulty is trying to make it a swinging arm. Most boat davits on hardboats lock in place before the load comes on.

This needs to be able to swing inboard. That also rules out the one over the bow suggested.

Also doesn't need to be super heavy duty.

Was thinking dive kit kind of weight rather than diver kind of weight.

I'd be interested in seeing any plans you made Nasher!

S

[treerat]

Originally Posted by Stevie J

Strangely, one technical difficulty is trying to make it a swinging arm. Most boat davits on hardboats lock in place before the load comes on.

This needs to be able to swing inboard. That also rules out the one over the bow suggested.

Also doesn't need to be super heavy duty.

Was thinking dive kit kind of weight rather than diver kind of weight.

I'd be interested in seeing any plans you made Nasher!

S

So an A frame that pivots out over the bow / tube would be good, acting as a deviation point more than anything else.

This could then be connected to a winch some where in line, if in the bow on the front of the console perhaps?

Once the load is lifted to the height required the a frame moves on it's allowed axis from pointing out over to at 45 degrees to vertical, bringing the load in, then lower the winch.

Stops / brackets at the 45 and 90 would be required but shouldn't be too hard if the max weight is a twin set.

[Stevie J]

Any sketches or plans would be great guys.

This may actually happen!