STEERING IN FOURTH GEAR
Istvan’s vessel might never be perfectly prepared for the Southern Ocean if the windvane self-steering system has to operate the main rudder in fourth gear.
There is a limit to what improvements can achieve because of the very high loads placed on the steering force transmission system. The materials ordinarily used will stretch and flex too much under the likely loads; in fact probably nothing short of wire cables would be up to the job. The wheel adapter will certainly give up next.
The existing indirect wheel steering system on Puffin was replaced with a Whitlock Cobra direct type to free up stowage space, but the Cobra is just not suitable for a boat with an unbalanced main rudder like the Tradewind 35. This is something no amount of tinkering around the edges can be expected to cure.
My calculations completed after I posted the last news blog indicate that unfortunately, the improvements described in the blog will not be able to compensate for the mismatch between the boat and its main steering system. Istvan’s podcast comments suggest that he is aware of the problem but is still minded to attribute responsibility to the vanegear, so a switch to a system could just land another manufacturer in the same difficult situation I have been facing.
I hope I have been forthright enough to prevent the disaster that could unfold if the boat were to continue into the Southern Ocean relying on such a fundamentally flawed setup.
Friday 20th of july 2018
Peter Foerthmann
