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Hey everyone,I'm after any rig specifications anybody can offer regarding doing a ketch crabclaw set up on my tangaroa mk 4,I'm uneducated the with technical side of rig balance but keen to use this rig.

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Matt - finally a sketch.  This is intended more as a start point for discussion than a proposal.

 The crab claw [CC] has a high ctr. of effort so even though this only has the same area as the cutter  [400] it has slightly less static stability [10%]. I do not consider this as very significant. In heavy weather it may be the other way round due to the short masts. Probably you would need equal sized masts + sails to correct this- ie. a schooner rig.

All measurements are in feet and feet2.

The main mast is on beam#1 and mizzen 1ft forward of beam #4.You would need a good trampoline aft for handling this sail. Yards and booms are equal and meet at 450.

The centre of balance is forward of ctr. lat. res. by approx 5% water line probably OK.

In any new departure like this you will probably end up changing some things. For instance my boat quickly develops weather helm under way. You may find you need a larger jib to reduce this.

Probably you will not get it perfect first time. Probably this will be half the fun !!

I never sailing in any crab claw boat, but I think without jib is better...

Like this:

That looks like a well rounded start to me Galway. I think to start with i will attach the spar and boom intersection to the bottom of the mast for ease of handling,maybe allowing the sails to tilt back when I've got my head around the rig a bit more. If the sails are set like in the second drawing Rogerio I can see difficulty in shifting them to the other side of the mast when needed,as if you left them on that side when the wind pushed the sail into the mast it would loose shape and de-power. Also having a jib for crusing into an anchoring etc would be handy.

Ok Matt this is one kick...we have a Crab claw sperts to anwser better

matt connolly said:

Isso parece um começo bem arredondado para me Galway. Eu acho que para começar eu vou anexar o mastro e retranca cruzamento para a parte inferior do mastro para facilitar o manuseio, talvez permitindo que as velas para inclinar para trás quando eu tenho a minha cabeça em torno da plataforma um pouco mais. Se as velas são definidas como no segundo Rogério desenho vejo dificuldade em deslocar-los para o outro lado do mastro, quando necessário, como se você os deixou para esse lado quando o vento empurrou a vela no mastro que iria perder forma e de-poder. Também ter um braço para crusing em uma ancoragem etc seria útil.

Permalink Reply by Rogerio Martin yesterday

Ok Matt this is one kick...we have a Crab claw sperts to anwser better.

Rogerio I cannot understand what you are saying here. No doubt it is just a language thing. It actually sounds a little insulting in English which I am sure is not your intention.

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