Beneteau first 47.7 Steering System

[Tomtom39]

All
I am currently refitting my beneteau 47.7 and as you will all know who are familiar with this boat it uses spectra/vectran lines for steering cables, they are very annoying as they need tightening often and also they tend to fray after a period of time.
Has anyone had a conversion done on their boat to wire cable. I presume the pulleys would have to be replaced. I am awaiting a call back from beneteau around this as they might have a conversion kit available? Thought I would ask the question
Thanks
Nick

[svHyLyte]

Originally Posted by Tomtom39

All
I am currently refitting my beneteau 47.7 and as you will all know who are familiar with this boat it uses spectra/vectran lines for steering cables, they are very annoying as they need tightening often and also they tend to fray after a period of time.
Has anyone had a conversion done on their boat to wire cable. I presume the pulleys would have to be replaced. I am awaiting a call back from beneteau around this as they might have a conversion kit available? Thought I would ask the question
Thanks
Nick

Nick--Where/how is the Vectran fraying? In theory there should be a fair lead from either end of the chains in the binnacle over smooth idler wheels to the quadrant. Is that not so?

[Tomtom39]

Hey
Thanks for the response. On the beneteau there are no chains. Purely vectran line.
The vectran line has two eye bolts splice to the end which attaches to the quadrant. The line then heads away from the quadrant at horizontal level. It then passes through 2 heavy turning blocks making the line turn at right angles towards the binnacle! The vectran is then secured through the shaft of the wheel. When you turn the wheel the rope gathers on the shaft and turns the rudder.
These boats were designed for class racing so made light as possible hence the light and feeble design of the steering.
Fraying occurs due to the tension required on the vectran line to ensure that it stays on the pulleys!!!!
Thanks nick

[donradcliffe]

Where is the fraying occurring?? If it is where the lines run on the quadrant, then perhaps the quadrant has rough edges and/or has been moved up or down on the rudder shaft so that the lines rub. If it where the lines go through the turning blocks, maybe they are not aligned properly.

[svHyLyte]

Originally Posted by Tomtom39

Hey
...The vectran line has two eye bolts splice to the end which attaches to the quadrant. The line then heads away from the quadrant at horizontal level. It then passes through 2 heavy turning blocks making the line turn at right angles towards the binnacle! The vectran is then secured through the shaft of the wheel. When you turn the wheel the rope gathers on the shaft and turns the rudder.
... Fraying occurs due to the tension required on the vectran line to ensure that it stays on the pulleys!!!!
Thanks nick

Nick--

That doesn't make sense to me. The sheaves in the turning blocks should be rotating with even modest load (tension) on the Vectran and surely should if there is enough tension in the vectran to chafe the line, which should only happen if the sheaves are frozen and the line is simply sliding over them. As I don't know the construct of your system, I cannot offer much but based on our own (older) system I would suspect the sheaves should have either UHMPE or greased bronze bushings. If the bushings are worn they might allow the sheaves to shift out of alignment and "lock-up" giving rise to the chafe. In any case, I'd check the turning blocks carefully before looking at going to wire rope.

FWIW...

[Tomtom39]

Thanks for your response
I will check the turning blocks this weekend
Thanks
Nick