Any diagrams for cradles to suit 10m mono hull?

[cocos]

Hi everyone,

i'm stuck on Cocos Islands in the Indian Ocean, not a bad place to be stuck, and looking for options to remove my vessel from the lagoon with the upcoming cyclone season.

One option is to build a jinker, but this may take some time. the other is to crane the vessel (10m Peterson) out then onto a engineer approved cradle.

Does anyone have some plans on how to build one of these?

regards

Tony from Cocos Islands

[jimbunyard]

Much depends on the availability of resources; Cocos is a long way from anywhere...

A proper frame for any boat is by nature an at least semi-custom endeavor.

To build either a jinker or cradle basically requires the same information; where to place the supports, and how many to use.

If you can get hold of a detailed drawing similar to this, with these projections, the job is easy,





measure where the bulkheads you want to support are, determine where that spot is located on the drawing and place the support at the proper height and distance from centerline (as determined from the drawing) on the ladder frame.

If you can't find drawings (I looked on line for about a half hour to no avail)
you can get pretty close measurements by securing the boat over a flat part of the bay and taking measurements at the appropriate places. This is of course aided by your location...scuba gear will speed things, but if you're a good snorkeler, that would work too.

The keel can rest on the ground (in the case of a cradle) or a cross beam made into the frame of the jinker (in which case it should be able to support the weight of the boat, in your case about 6 tons).

The supports should be stiffened with appropriately spaced, angled and sized braces in two dimensions, especially with a jinker, as it has to bear the added stresses of movement.

It should be kept in mind that wood can be used for this purpose as well, or a combination of wood and metal. Rollers can be used instead of wheels, depending of your traction power and substrate you may be able to just 'grease the ways' and skid the thing into place...

A good, experienced builder should be able to be found on the island to assist, he need not be a formal engineer...but he should have good references.

And finally, if this is not to be permanent, since the archipelago is only about 10 x 7 miles, might an investment in some extra good ground tackle and keeping an eye on any approaching storms to find the best lie make more sense?