UK yacht Cheeki Rafiki missing in mid-Atlantic

[deluxe68]

Originally Posted by goboatingnow

The first series, like many racer-cruisers, and unlike cruiser- racers are designed to be competitive at handicapped racing events. Hence they are designed with very high aspect keels, shallow canoe bodies with low wetted areas and any unnecessarily weight is stripped out. The result is a vessel with very small , if almost non-existent bilges and a difficult keel connection.

In many high end vessels this was solved by interior metal grids etc, but notably even x-yachts had to abandon that in favour of carbon-fibre grids to remove weight so as to stay competitive.


Racing ability is typically what these vessels are bought and the design decisions, material, weight,costs are a typical compromise to engineer a fairly low-cost competitive racer- cruiser. In fact the compromises in the first series are more abrupt then in dedicated racers like say the Archambault A40.

Simply boiling this down to the stud diameter is misplaced. strength or durability is simply not a function of making things bigger.

dave

I would not categorize the first series as racer-cruisers, they are too heavy for that. Just look at the difference between the 34' J105 and the 36' 36.7. The J105 weighs 7,700 lbs while the 36.7 weighs 13,000. Cruising World puts the 40.7 in the Cruiser/Racer category.

[Ozbullwinkle]

I didn't realise that the bolts are gal steel, that's a surprise.

[sailorboy1]

Originally Posted by goboatingnow

This is no a failure of a series , this is a specific failure on a specific boat

you aren't going to get most haters to accept this, far as they are concerned this failure applies to every boat made by the manufacturer (way beyond a series)

[goboatingnow]

Originally Posted by sailorboy1

you aren't going to get most haters to accept this, far as they are concerned this failure applies to every boat made by the manufacturer (way beyond a series)

I know, I find singling out mass production boats , especially European ones, somewhat bizarre. All manufacturers have good and poor models , som emote suited to specific activities then others etc,

Is it something to do with not having any sail boats and everyone being in small sports boats or something

dave

[donradcliffe]

Originally Posted by Ozbullwinkle

I didn't realise that the bolts are gal steel, that's a surprise.

They're not--Bene uses gal steel bolts with their cast iron keels, but the First 40.7 has a lead keel with SS bolts.

[Cavalier]

Originally Posted by donradcliffe

They're not--Bene uses gal steel bolts with their cast iron keels, but the First 40.7 has a lead keel with SS bolts.

..actually, their cast-iron keels use thread-inserts. I called and asked them! SS 18-8 bolts are typically used for all keels, see Beneteau keel-assembly guidelines:
http://www.cruisersforum.com/forums/...ml#post1554208

[transmitterdan]

Thanks for sorting that out. It must have been another thread I read of a keel held on with galvanized bolts. Sorry for the diversion...

[DumnMad]

Originally Posted by goboatingnow

The bolts on the first are either M22 or M20. To suggest that they should be M60 or M80 is quite ridiculous , there isn't enough material across the Keel for that

Many 1000s of first have been made in various guises. The vast majority are fine and many have many bruising deep sea races to their credit.

In my view , cheeki was an old boat, very very extensively raced, it's was in effect 3 to 4 times it's real age, I suspect there either existing damage, incorrectly refitted keel or so e combination of pre-existing damage. It was unfortunate that the 4 men in question happened to be the ones to be there when the time ran out.


This is no a failure of a series , this is a specific failure on a specific boat


Dave


Sent from my iPad using Tapatalk

Agreed. Fatigue failure of some bolts, followed by concentration of loading on remaining bolts in a small area, then hull ripped out.
ss bolts under cyclic loading need to be replaced just like hard-worked stainless rigging has limited lifespan.
Problem is its very hard to know when the time is up. Boats never raced or out in stormy weather would be safe even at twice the age.