Does anyone know the spec of the rudder pivot bolt? The one I have removed is 3 inch by 1/2 inch with a 1.25 pitch. I am struggling to find the spec anywhere to order a new one.

I think all the nuts and bolts on the Sinbads (and the 22s) were Whitworth. As long as it's stainless I don't think it matters if it fits.

Geoff (ex Sinbad 287 Zalophus)

While trying to find half inch bolts (to attempt to stop the slop on my well worn M12 pintle holes) I came across the source below who were very helpful on the phone and can get A4 quality as well from the US.
If you are happy with A2 they should have the 3 inch length in stock.
Chris. SS Elsa


Stainless Steel Centre Ltd
Unit 4 Renown Close
Chandlers Ford Industrial Estate
Eastleigh
Hampshire
SO53 4HZ

Tel: +44 (0)23 8027 1155
Fax: +44 (0)23 8027 1110

E-mail: sales@stainlesssteelcentre.co.uk or sales@nuts4bolts.com

Double checking ... they should have A4 in stock as well.

Thank you all for the replies.

A normally very reliable local supplier measured my pivot bolt and declared it to be M12, but he didn't have them in stock. I ordered minimum quantities (2 bolts and 5 nuts) from Peter Bentley in Paignton trading as "Aruncas" on ebay. Of course they are wrong. With help from the YBW forum I am convinced it is 1/2" UNF. I have just returned the M12 stuff and re-ordered UNF items from the same source. They are A2.

I'll report here when they arrive. If I don't then you'll know I was wrong again and I've probably thrown them through the garage window along with my dummy and all the toys out of my pram!

I could use the old bolt at a push but I want a new one to go with my shiny new laser cut rudder blade. I'll try and update that thread with pics tomorrow.

Floyd

Well glad tidings: the new bolt is perfect!

So for the record it's 1/2inch UNF x 3 inches long. It's A2 stainless which is OK for me as I'll be in fresh water and keeping an eye on it anyway with regular maintenance. The only thing missing is the tiny hole for a retaining wire but the new nyloc should suffice.