Rear stay tension - Help

[miamiz]

I de-masted my 27ft Hughes when my chain plate failed a few months back. I took the opportunity to repaint and clean all the mast hardware. I hired a crane to re-step the mast and loosely tightened all the turnbuckles. I found a video on YouTube on how to center the mast port to starboard but not on aft to bow. I measured the turnbuckle gap from the previous setup. I guess I should mention that this is a deck stepped mast. Anyway I tightened the rear stay pretty tight but it still lacks an inch in the turnbuckle gap from the previous measurement but it seems really really tight. While the rear stay seems really tight the front stay seems loose and has allot of play. Having a roller furling I am only tightening the rear stay. So I'm a little phobic continuing to tighten the rear stay but there is no noticeable mast bend and all that furling play. So should I keep cranking down the rear stay?

[sanibel sailor]

Not too familiar with your boat, but...
Does she have paired lower shrouds? They should be loose to start.
Are you sure you hooked the forestay and back stay to same holes? Some stemheads have several spots. If the lower shrouds are loose, cranking the back stay tensions the head stay, especially so with a deck stepped mast. As you probably know,the furler is adjustable, although many do not want to fool with it, and unless you are trying to do something fancy with weather helm or sheeting points, there is not much point.
Most rigs are too loose. Being too loose is worse for it than a little too tight, as it causes shock loads.

[S/V Alchemy]

Acquire or borrow a Loos tension gauge and figure out your stay diameter (it's probably 3/16ths or 7/32ths or something close to that. Learn how to use via a YouTube. Adjust as necessary.

The gap in the turnbuckle is largely irrelevant as the number of turns required is predicated on where the mast is placed on the step/tabernacle, the tension in the forestay, the amount of pre-bend (if any) and so on.

From your description, I would suggest (as a very crude start) to slack off the rear stay and to tighten down the forestay. You want a tighter fore than rear stay, for the simple reason that the boat sails forward 99.9% of the time, and the tautness of the forestay determines the effectiveness of the foresail.

There are a zillion web resources on "tuning the rig". Read a few and get back to us. And borrow a gauge to get it zeroed in.

[barnakiel]

Goo gle up Selden rig tuning manual; it discusses many rig configs. Downloadable in pdf. Very good stuff.

b.

[neilpride]

Asuming you have a turnbuckle in the roller furler , go back to the begining, drop the sail from the furler if you have the sail up, loose both turnbuckles , backstay and forestay, keep in mind that when you start to turn the turnbuckle in the stay he need to be equal in both sides, bottom togle and top wire screw, now keep turning by hand both stays , forestay and backstay until you feel hard to continue by hand , look up to the mast and see if is straight , no leaning forward no backward, from this point is where real tweaking start,you need to have enough turns in the forestay screw until you feel the mast is going to lean forward , there aply turns in the backstay screw and keep looking up to the top , if both sides are tight enough and the mast is straight you can make some rake aft by turning a bit more the backstay, goo sailing and check the forestay sag upwind, some banana form at the furler is normal, haa btw , to see if you have the mast out of level at the step , use a feeler gauge , the perimeter of the mast need to sit evenly in the step.. hope this help ...

[sandy stone]

With a deck-stepped masthead rig (I'm assuming that's what you have) the headstay tension should equal the backstay tension unless something else is going on - like the forward lowers or inner forestay being tight, something like that. Stop and take a look around, something is preventing the mast from angling backwards.