Any suggestions please on what sort of tension the wire should be set to when the boat is rigged ?
E flat, G sharp, diminished minor 7th ? Or just until it feels twangy ?
On the bobstay, the tension is less important than the length, which has a fixed dimension. That length should allow the sprit to remain in line with the shear line of the gunwales. The eclipse "bobstay" is a solid rod for example. The tension is achieved through the forestay tension. Twangy then.
TG
So one day I was sailing and noticed my bow sprit was moving up and down ... hummmm what gives?
So I heaved too and crawled up to the bow. Looking over the side I saw that the dolphin stay had parted!
Yep it broke. Don't know how. So I tied her down best I could with a line and once back on the dock removed the parted thing.
Had a new dolphin swaged together, and when installing it at the bow ring first, I realized that the eye under the bow sprit was half a pin diameter short ...
What to do? Back to the line thing again. I rigged a line 'tween the two points and started twisting the line with a long screw driver. This shortened the line [like winding up a rubber band motor for a model aeroplane] pulled the bow sprit down until that half a pin diameter was made up. It 'Twanged Nicely'.
Then the fore stay and back stay can be played with for tension. Just remember that 'too tight' tends to shove the mast through the bottom of the boat.
Following the shear line is the best idea.
Where there's a will, there's a way.
skip.