Davits - rope or wire?

[Jamesuk]

I have been having too much fun with our wire davits and i have been on much larger yachts which use spectra or dynemma to lift their tenders and we use wire to lift our dinghy. The end is weighted but for anyone who knows what it is like to lift or launch a dinghy in a sea or when a mobo passes just at the moment you clip on, it can be a frustrating affair not because of the concern for the tender but mainly, will the davit wire be damaged and jump off its coil to land in the gears.

I have seen a few Oysters with hydraulic davits that if anything launch the tender faster than you have had time to realise what you have just done but doing so using rope (spectra). On a 250 yacht i was on the davits came out of the side of the hull and the 31ft tender was launched using spectra.

On a much smaller boat and the worry that guests or even the crew cause the wire to kink (no weight) then surely a rope would be the ultimate problem solver?

Anyway it would be good to know your thoughts

Ps the wire is excellent in the hands of the person who has had to take apart the davit to put in a new wire but everyone else :-//

 

[oceanfroggie]

Touch wood, we've never had problems with wire on 175kg x 2 Electric Simpson davits holding a 3.8m RIB with 30hp motor. Rope wound be kinder on hands alright but not sure if it would work with smaller davits like ours. Certainly out in a blow the wire gives a degree of comfort that rope woud not. We use straps under the tender to secure it and stop it moving if we are working a bit of a mucky sea. I can see though that if the wire wasn't loaded it could jam inside.

 

[jfm]

Just on the terminology, many people (esp N Europe where much of this forum readership is based) take the word "davits" to mean the arms that hang out over the transom with a tender hanging on, whereas others (eg in S. Europe) "davit" often means a crane.

I have a besenzoni davit (=crane) with wire, as standard, and it works fine. I can see the benefits of rope, but they aren't enough to make me go to the trouble of changing the steel wire, which works perfectly well. I know what you mean about passing wakes etc but I always run stabilisers when using the crane and anyway I find, to my pleasant surprise, that the wire doesn't ping off the drum even when there is no weight on the hook. I find that the weight of the wire alone, when say 4m of it is hanging from the flybrisge, is enough to keep it on the grooves in the roller/drum

 

[DAKA]

(I have Small stern mounted davits)

I use rope which is doubled to a pulley holding the hook.

there isnt enough weight in the rope/pulley/hook to fall, it requires a good pull.

the rope is a good deal thicker than wire, you need to be sure the spool is large enough to take the thickness.

I have seen kevlar rope used which is thin enough however it weighs even less but would work well if a weight was placed around the hook.

 

[SpottyDog5]

Shameless advert for my new company, but I'm sure it will be of interest (website just gone live-still work in progress)

www.rapidmarine.co.uk

btw will soon add belly straps.

 

[ccscott49]

I had wire on my stern davits, but have changed to spectra, with a three way pull on pulleys, great makes it so much easier to lift my 3.6 rib dinghy and 30hp motor, plus no damage to hands if come in contact with it.

 

[superheat6k]

On OB the previous owner swapped from wire to Kevlar falls, these seem fine, but they do look flimsy. I have fitted 8mm rope safety lines that pass under the belly when the RIB us stowed to / under the davits. 3.2m Rib with 15HP outboard.

My winches are very noisy / creaky but due to the clutches I am loathe to spray any form of lubricant on. Any ideas ? I think they are Whitlock units.

 

[Jamesuk]

Hi,

We have a tiny weight on the 225kg Davits (max lifting weight) a rollaway dinghy with 8hp. I know I know. Could almost take a Williams jet RIB!

So I have got familiar with these Davits what happens when the wire is slack it jumps into the gears and then when operated gets chewed on the gears. Simpson have addressed this by supplying a retro fitting a gearing cover (plastic) so far so good.

The dyneema I had in mind would stop the clunking and when slack would not send the slack all the way to the drum holding the wire.

Th

 

[Keen_Ed]

FWIW, wire is on its way out on sailing boats. For any running rigging, rope - normally dyneema - is now king. Kevlar rope isn't really used any more, as it doesn't like going round corners. Current trends is for rope (well, carbon "rope") to replace wire on standing rigging as well - racing boats only, atm.

Much nicer stuff. Doesn't slice your hands open, for one thing.