Forestay/Backstay Tension

[bc3737]

Morning All,
Been away from this forum for a while and trying to get an answer about something that has always "bugged" me.
Is there a "correct" tension for the backstay?
After rigging the mast (following West Sail documents) the backstay seem to be a "bit" loose? I "feel" that it should be tighter.
Beating to wind ( in a fair blow) the forestay seems to, for lack of a better word, seems to sag to leeward......Doesn't stay straight and tight...creating a "sack" out of the gennie (reefed or not)..

Make any sense??? Any help is appreciated.
Bill
My White Dog

 

[shnool]

Sounds like you need more forestay tension, or your lowers our out a bit.. One thing I always forgot with mine was, the forward lowers, should be tighter than the aft lowers (pre bend)... when the backstay (adjustable) is fully off, you should have some sag in the aft lowers.

Since the Cat 22 doesn't normally have an adjustable backstay (you don't have one do you?), then you should tension the backstay until the aft lowers tension up a bit (put a bit of bend in the mast). How much tension should be dictated by your average winds (which is a trial and error thing).

Ideally you'd bend the mast more as the winds pick up. Just keep in mind this changes the Center of Effort, and would induce more weather helm.

 

[watercolors II]

Loose is good

Your forestay should be loose so that the leading edge of the head sail bowes forward and to leeward as you say yours does. This twist in the front edge of the sail allows the whole back edge of the sail to point towards the stern for power. If the forestay is tighten and takes some of this bow out of the leading edge the bow will now be transferred to the back edge of the sail. The top part of the head sail will twist out away from the stern and start dumping air off the top of the sail, thus de-powering it.

The next time you’re out on the foredeck and looking up at the headsail have someone tighten the backstay adjuster as someone has suggested or have that person pull the backstay sideways as far as possible, this will pull the top of the mast backwards and tighten the forestay, watch the top back edge of the headsail start to twist out to the side of the boat.

For the forestay to be loose the backstay must feel loose also, when the sails load up with wind they will push and pull forward on the mast thus making the backstay tight.