Dingy Davits?

[blefever]

I have a new to us Mainship 350. There is currently no dingy davits or chocks. I want a 11-12' RIB with molded console to explore in when we are cruising.

I don't want to block the swim step so we can still use the transom door and get on and off the boat for docking. Climbing over the cockpit side is doable just not ideal.

Ideal in my mind would be to carry it on the hard top, out of the way and secure, but I'm not sure the hardtop would handle the weight of the crane and a 450lb dink without causing stress cracks or other problems. I also question how much it would affect the stability in the open ocean, although 600lb is 3 people on the flybridge...plus or minus a few pounds.

The foredeck is another option but not a good one for my likes.

So anybody have any thoughts on the hardtop or a davit system that is secure, easy to use and out of the way?

I don't ask for much do I? lol

 

[Comodave]

We put a SeaWise davit system on a previous boat. It mounts on the swim platform but it leaves one side open and some limited access to the other side. It makes it easy to launch and recover the dinghy. About a minute to launch and a couple of minutes to recover. The motor stays attached and stands vertical over the platform when stowed. It isn’t cheap but it is custom built and very well built at that. No affiliation.

 

[Bud]

You could have both set ups. Then choose which to use considerating your needs. I started with davits on the stern and then changed to a crane to place tender on trunk cabin for similar reasons.

Bud

 

[Rufus]

The Nick Jackson on our boat leaves plenty of room for starboard side access via the swim platform.

 

[DavidM]

You are planning to hang a 12' long, heavy (with the console) RIB dinghy (well let's call it a tender at that size) from a 35' boat. It probably weighs 600 lbs with engine and fuel. That size and weight RIB is more often seen on a 45' boat. I don't think the swim platform can take that kind of weight.

David

 

[Bill V]

You are planning to hang a 12' long, heavy (with the console) RIB dinghy (well let's call it a tender at that size) from a 35' boat. It probably weighs 600 lbs with engine and fuel. That size and weight RIB is more often seen on a 45' boat. I don't think the swim platform can take that kind of weight.

David

I must agree completely. At 14' beam a 12' RIB will be tight at the transom. Any davit system mounted to carry the RIB on the swim platform will max out any supports the factory used more then likely. That leaves mounting of davits to the gunwales and with a transom door the starboard end of the transom gunwale will be weakened due to it not being tied into the starboard gunwale as the port side is. A 9' RIB and 9.9hp engine would lesson the weight to about 200# which is much less then the estimated 450# of a 12' RIB and engine.

 

[koliver]

I have a new to us Mainship 350. There is currently no dingy davits or chocks. I want a 11-12' RIB with molded console to explore in when we are cruising.

I don't want to block the swim step so we can still use the transom door and get on and off the boat for docking. Climbing over the cockpit side is doable just not ideal.

Ideal in my mind would be to carry it on the hard top, out of the way and secure, but I'm not sure the hardtop would handle the weight of the crane and a 450lb dink without causing stress cracks or other problems. I also question how much it would affect the stability in the open ocean, although 600lb is 3 people on the flybridge...plus or minus a few pounds.

The foredeck is another option but not a good one for my likes.

So anybody have any thoughts on the hardtop or a davit system that is secure, easy to use and out of the way?

I don't ask for much do I? lol

LOL No not much!

Your Mainship has a beam at maximum of 14'2". at the transom it will be less, likely no more than 13'.
A dinghy that is sold as a 12' will measure around 12' to the end of the tubes. When an outboard is attached, it will be longer, likely adding over 1'.
With a molded console, it will weigh more than you think. (my 12' is >750#)
Your swimgrid is not made to carry the weight of a heavy dinghy, so any davit attachment that sits on the swimgrid will require modifications to the swimgrid or to its supports.

No davit system at the transom will be out of the way.

The above "Nick Jackson" on an OA 44 puts no load on the swimgrid and can be mounted so that the access from the dock to the transom door is clear, on the OA. On your boat?? Any pictures I can find of the M350 show the door in the exact centre of the transom, so effectively blocked by every davit system.

Hoisting to the upper deck will require modifications to the deck, to carry the weight, and will likely limit the length of dinghy you can carry to less than the 11" you specify. Again, any pictures of M350 upper decks show no room whatsoever for a dinghy.

Sorry if this is not what you need to hear.

 

[blefever]

You are planning to hang a 12' long, heavy (with the console) RIB dinghy (well let's call it a tender at that size) from a 35' boat. It probably weighs 600 lbs with engine and fuel. That size and weight RIB is more often seen on a 45' boat. I don't think the swim platform can take that kind of weight.

David

Hi David. Thank you for your reply. Just to be clear.

The Mainship 350 is actually a 39.9' boat with a 14.2' beam. The swim step is molded into the hull. The manufacture of the RIB I plan to purchase says weight with motor and fuel is 475lbs. I'm sure the swim step will handle any type of davit system I choose, but my main concern is access to the swim step with the tender in place and when the tender is in the water.

That is why I would prefer to have it up on the hardtop out of the way but that location is going to be the biggest job and that is also where weight concerns come in. After looking at boats with tenders on the hardtop I feel it would be fine but if I choose to go that route I may need a navel architect to chime in. Thanks again for your thoughts.

 

[Rufus]

The 9' center console rib came with our OA 44 when we purchased the boat. I like the Nick Jackson davit a lot, but would opt for a simple, non-console rib with a two stroke motor if I was making a "new" purchase. The current dink is too heavy, requiring full trim tab if I want to get the aft end of the mother ship up for semi-plane operation. Once out of the hole it's fine...

No way would I have a dinghy on the roof. Stability issues and a nightmare to load/offload in even the slightest wave action. Forget it in a narrow slip.

 

[Comodave]

Check out SeaWise davits. They will leave access to the swim platform. I am not sure what the weight ratings are. And if you want the platform completely open at the dock or on an anchor you can drop the dinghy into the water in literally 1 minute. It will stay attached to the platform and just stay attached to the brackets so you don’t even need to tie it off.

 

[Derek]

We installed these on our Mainship 400 and they worked great. Easy to single hand, no mechanical items to maintain... https://www.boatdavit.com/Home/Details/2

They have options for heavier setups like yours it was very satisfied with the quality of the product. I have no financial interest in this company.