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My old Tiki 21 have one bow bad. I need exemples of wharram How to fix the stay.

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Hi Rogerio,

I attach some pictures of the arrangement in my T26.

The bridle of the stay is connected to a stainless steeel plate, that is fixed to the bow by two screws passing through the bow to another plate, so the load is is spread on a wider surface.

Here are another pictures. If they are not clear I can take more pictures.

Regards,

Andrés.

Those U-bolts look too long. The force from the bridle is not transmitted directly to the bow, but is levering the u-bolt. You need stubby u-bolts or, as it has been suggested, dyneema loops might be better still. It will be a tricky repair involving cutting a section to increase the area for epoxying in new material. You might need to place an addition section on the outer surfaces to increase the strength, perhaps a stainless plate. You could scarf in a new section with two scarfs, with the new wood mainly on the outside.

Obrigado Andrés, devo fazer igual ao seu.



Andrés said:

Aqui estão outras fotos. Se eles não estiverem claros, posso tirar mais fotos.

Saudações,

Andrés.

I don't like this much and warn against it because of fatigue failure. The bent steel strip will flex, work harden and fail suddenly. Be careful! 

It looks strong to me and the connection allows flexibility, but I am not an expert in this topic. Also I don't trust very much in stainless steel, because it can break without warning. In my case, I started to use two halyards, one to each bow, as a backup and this gives me peace of mind.



Ian Bamsey said:

I don't like this much and warn against it because of fatigue failure. The bent steel strip will flex, work harden and fail suddenly. Be careful! 

yup

Eu usei assim no  TikiRio



Andrés disse:

A força forte para mim e a conexão permite flexibilidade, mas eu não sou especialista neste tópico. Também não é fácil, mas não é um aviso prévio. No meu caso, comecei a usar duas adriças, uma para cada arco, como o apoio e as pazes do espírito.

Looking at the photos,the U bolt set-up is too close to the bow. Quite a lot too close, irrespective of the leverage from the long U section on these.

When working mine out, I saw this immediately as another problem inadequately dealt with/specified  in the plans - sorry Wharrams.

I found the longest U-bolts (ie their tails) I could buy in A4 10mm diameter, placed them well back from the bow extremity, about 70mm.  Drilling and fixing for them was quite difficult. It's all by eye. On the outboard side on my boat, the plate is countersunk into the side entirely, but even then there's at least 50mm of meat behind the plate, and when I made the stems I laminated them very strongly, so it's at least 50mm of lam ply/epoxy on there between the nuts and the outside, not just ply.

On the outboard side I then cut in for some 6mm tufnol cover plates which are masticked in, so I can remove them easily when I like and inspect the bolts/washers/nuts for corrosion etc. (TIKI 31)

A wrap-round ss plate might help I suppose on some set-ups, as has been said.

I was quite annoyed about this detail, glossed by Wharrams: the U-bolt parameters should have been clearly stated.

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