How to accomodate a tender

[stewart]

Has anyone got experience of fitting a tender to the back of a boat with a relatively small bathing platform? The boat is a Sunseeker Camargue 46 and has both a passarelle and telescopic davits with it, neither of which have been fitted yet, and has a bathing platform which comprises two steps, each about 18" deep, so not wide enough to hold a tender. I was thinking perhaps of a jet boat if this is a possibility.

So here are a few questions:
1. What weight can be supported on telescopic davits (or should I fit bigger davits)?
2. Would a crane be a better option and what might this cost?
3. How would the tender be held in place when the boat is in motion (I presume not just dangling from the davits)?

Any thoughts?

 

[Deleted User YDKXO]

Stewart, either you hold the tender in the davits or you have to have extended supports fabricated for the tender to rest on. I'm guessing here but I would be surprised if the telescopic davits had a capacity of more than 100kg each. As a general rule of thumb, the weight of the tender should not exceed the capacity of 1 davit so this would limit the tender weight to about 100kg. If your tender weight exceeds this, then you would have to fit larger davits (assuming the transom mounting points are strong enough - Sunseeker could probably help you) or fit a crane. Alternatively, it may be possible to use the passarelle as the crane if it is hydraulically powered
The jet ski would be too heavy for davits and is not the right shape to fit them anyway so you could only carry this on supports fixed to the bathing platform. I've seen supports fabricated in timber or stainless steel but once again you'd have to check whether the bathing platform is strong enough to take the load
I believe an electric or hydraulic crane would cost maybe £4-5k. Try Cooney Marine (sorry dont have the address)

 

[Guest]

a jet boat (not jet ski, i think mike had slip of kboard) is too heavy for davits. But yes, the tender does just dangle, although there are additional lines to tighten it up and make sure it doesn't dangle a lot.

Aside from the weight, there's the width too, which normally limits the lenths of the dinghy, and hence the power output of the outboard, and in turn the overall weight.

From seeing others, dinghy plus 15 hp is your limit on davits on that boat, remove plug to allow rain to drain away. Jetboat requires er a Princess V65, in a garage.

 

[ArthurWood]

I don't know anything about the geometry of a Camargue, but have you looked at TNT lifts. These are hydraulically operated swim platforms, which can be raised and lowered and can accommodate jet skis, RIBs etc. They are popular on the bigger Sea Rays in the US, but I don't know if they distribute in Europe.

 

[Guest]

There are various alternatives and apart from the obvious issues about will my arrangements carry the type of tender I am contemplating, you should also think about what will happen to the lines of your boat. On a flybridge cruiser, the saloon/flybridge mask the effect of carrying a tender on high davits. On a sportscruiser, they can look really naff. On the other hand, davits generally will carry the tender high enough to allow use of the bathing platform with the tender in situe.

If you opt for davits, each davit has to be able to carry four times the vertical load imposed by the tender static so if you have a tender with say a 15hp outboard, the engine end is going to weigh around 100 kilos and you will need davits capable of carrying 400kg. This is because when a boat is in a sea, the bouncing motion effectively causes stresses on the davits far in excess of the dinghy's dry weight - to illustrate imagine holding a bag of cement - now throw it six feet in the air and catch it -this simulates a big sea. Your telescopic davits will not cope unless you unship the outboard every time and simply carry the bare dinghy.

Also, if you have a rubber tender -either a rib or a conventional dinghy, fit a proper davit kit as without it, swinging on the davits will quickly wear through the material.

I am not sure that the additional cost of a jet boat is justified. A small rib with a suitable outboard can be as much fun when required and much more practical when it comes to ferrying people/cargo to and from a mooring.

Look at whether you can use your passerelle as a crane and have extending brackets off the bathing platform to carry the tender.

An alternative are snap davits if you are using a small rib or rubber dinghy but these also would require removal of the engine.

Bon Chance!

Nick