Outboard Lifting Davit Arm

[silverp40]

We have an outboard lifting davit that is attached to our aluminum bimini top. The design is not great hence it bent after lifting our 6 hp OB. I have a few ideas for designing one made out of aluminum thick walled pipe, perhaps schedule 80, about 2 1/2 " diameter or so.

Does anyone have an outboard lifting david system/ arm that could post a photo or two to give me another idea for design??

Any ideas would be appreciated!

Cheers

[Conchfritterz]

We would be interested in this information as well. We have the bottom half of a hoist that came with the boat, the top half is missing and we are looking to do something ourselves to make it complete.

[silverp40]

This is the outboard lifting davit before. The bend is where the gusset ends. A few more hoists and the arm would bend much further . We stopped using it when it started bending.....

[silverp40]

Here is the new davit..A bit overbuilt but I really did not want to do have any more bending issues again. The new one is stout enough to pull an overboard crew back in the boat.

We use a 6 hp outboard, about 55lbs.

[capngeo]

Your design only transferred the bending moment to the vertical component. Even though the "boom" section is beefed up, and certainly more aesthetically pleasing, I would use extreme caution in lifting a person from the water...... especially if there were rough seas as then a dynamic load would be added as well.

[silverp40]

Yes, the vertical component puts more weight on the vertical axis...less load on the arm.

I did an unofficial test by which I hung from the end of the arm and jumped off the boat, thereby creating quite a bit more downward trust than my 190lb weight. The arm and structure hardly bent- it is 2 1/2" schedule 40 aluminum pipe and the welds are beefy and quite unattractive.

Aestetically I think it looks kind of kooky but it is useful nonetheless. Thanks for the comment.

BTW, hope that Isaac did not damage your boat - I see you are in Key West and SW Fla....

[Cheechako]

why not just a cable or rod from the tip of the davit up to the vertical above...?

[silverp40]

why not just a cable or rod from the tip of the davit up to the vertical above...?

The vertical pipe has a wind generator and is only 1 1/2". It will bend a lot if weight is placed there - more leverage...

Plus, the davit arm also turns 360 degrees on it's pipe base (2 7/8" diam).

[jackdale]

This is set up on a Nauticat 37 I used to use.

The engine is a very heavy 9.9hp 4 stroke.



A block and tackle could be led to a winch.

[Florida Mike]

Take it to a good welding shop and have a piece of flat welded to the bottom after straighting, or get a thicker walled pipe and/or have a piece of flat plate put tightly inside. Mike

[silverp40]

Hi Mike

check the before and after pictures....

[Capt.Fred]

Below are some photos of the outboard hoist installed in my Rob Roy 23 for my 4 stroke Tohatsu 8. It weighs about 84 lbs. The hoist also swings over the side and has a 4:1 pulley. It has been very covenient for keeping the outboard out of the water. I also have a water proof plug that closes the well opening for adding a little speed or off shore sailing.

[silverp40]

That is a nice set-up.

We use a 3 to 1 although our outboard only weigh about 55 lbs so we manage....the cam is a nice idea!

[jeremiason]

Originally Posted by silverp40

We have an outboard lifting davit that is attached to our aluminum bimini top. The design is not great hence it bent after lifting our 6 hp OB. I have a few ideas for designing one made out of aluminum thick walled pipe, perhaps schedule 80, about 2 1/2 " diameter or so.

Does anyone have an outboard lifting david system/ arm that could post a photo or two to give me another idea for design??

Any ideas would be appreciated!

Cheers

Garhauer Marine makes one that I used on my last boat for a 9.9 HP 4 stroke outboard... It worked well and cost far less than most marine stainless shops can do it for.

Garhauer Marine Hardware -5072215

[silverp40]

We have had a few things built by Garhauer and the quality of work and materials is always first quality.

The prices are also very reasonable.

Mike, head of the ss shop can build some beautiful custom made pieces!