|
|
Post by mastic on Jul 19, 2011 3:46:34 GMT
I have the lightess dingy/engine convination that can plane.
AB Ventus 10.6 , 123 lbs and a
Honda 20 Hp, 104 Lbs
Total Weight : 227 Lbs
St Croix marine is offering me a Davit System that will be atached to the transom and to the railing, with a reinforcment aluminium tube from the railing to the side of the helm layzerette, landing on side of the fresh water shower.
Transom atachment will be with a backing plate.
Has anyone has done this ? Will the transom and the railing support 227 Pounds ?, let's said 187 pound on the engine side ?
How can I make the backing plate stronger ?
|
|
|
|
Post by Zanshin on Jul 19, 2011 9:24:50 GMT
When I asked about attaching a Jordan Series Drogue to my 49DS transom which would generate in excess of 10,000Lbs in backwards load during a storm Messr. Briand replied that it would easily take that load and more and I should just spread it a bit with a larger backing plate. I would hesitate to say that your transom should have no problem with a mere 227Lbs, even assuming a 4G acceleration during wave action coupled with your tender filling with some water.
It all depends upon the design and where the loads are supposed to go. Most of the dinghy davits on the Sunsail/Mooring BVI charter cats failed very quickly as they weren't sturdy enough; either the charter guests treated them incorrectly or the Caribbean chop got to them. I gather that they are now further reinforced by the manufacturer.
If the main weight is born by the verticals to the transom and the railing support is just for lateral stability then it should not be a problem. How experienced in St. Croix Marine in davit systems? Can you get reference customers from them?
|
|
|
|
Post by electricmonk on Jul 20, 2011 21:13:34 GMT
I have the lightess dingy/engine convination that can plane. AB Ventus 10.6 , 123 lbs and a Honda 20 Hp, 104 Lbs Total Weight : 227 Lbs St Croix marine is offering me a Davit System that will be atached to the transom and to the railing, with a reinforcment aluminium tube from the railing to the side of the helm layzerette, landing on side of the fresh water shower. Transom atachment will be with a backing plate. Has anyone has done this ? Will the transom and the railing support 227 Pounds ?, let's said 187 pound on the engine side ? How can I make the backing plate stronger ? I have experience of davits and dinghys - weigh the dinghy when its full of water and report back! I suspect you will get to around 3000 lbs. This is what will happen in a worst case scenerio, and if it happens you WILL have quite a lot on your mind and a dinghy full of water hanging on the stern will really spoil your day. The davit arrangements I have seen on 49ds transoms are very flimsy. Hang on one and see how the transom flexes - not good. The usual series of events is, transom reinforced davits fitted, transom flexs so more reinforcement, transom still flexes, davits abandonned. The transom is not as strong as an aft cleat or a winch and Jordan admit their drogue will pull a winch out of the deck! make your own conclusions. Its the snatch load that does the damage. |
|
|
|
Post by dublin on Jul 20, 2011 21:56:09 GMT
We use rachet straps to secure dingy to transom when on passage between anchorages. Stores in vertical plain similar to snap davits but without the cost and the load is spread more . Also cannot fill with water in that position.
Rest of time dingy is deflated and in locker.
|
|
|
|
Post by Tafika II on Jul 31, 2011 17:04:14 GMT
I have an arch which supports a Caribe C10 with 15HP Yamaha, but when cruising long haul, I remove the engine and place it on the after starboard rail on a Edson OB mount and turn the RIB upside down & lash is to the foredeck. If a wave fill the dingy hanging on the arch, I would probably loos it all. I did run a brace from the edson attachment rail to the lower stern base for added support. It also acts as a handrail for the swim ladder & when boarding the dingy.
|
|
