BoatBanter.com

BoatBanter.com (https://www.boatbanter.com/)
-   General (https://www.boatbanter.com/general/)
-   -   Slack Forestay (https://www.boatbanter.com/general/48658-slack-forestay.html)

[email protected] September 16th 05 11:08 PM
Slack Forestay
 
I have been experiencing a problem when beating in moderate+ winds. My
foresail is a masthead rig(?)a large genoa & really 'bangs' when
sailing close to the wind, this in turn is transmitted down the mast. I
know that the rigging is probably on the slack side, particularily the
forestay (its at the end of its adjustment at the bottlescrew), would
this be the likely cause or should I be looking elsewhere?

Don White September 16th 05 11:38 PM
wrote:
I have been experiencing a problem when beating in moderate+ winds. My
foresail is a masthead rig(?)a large genoa & really 'bangs' when
sailing close to the wind, this in turn is transmitted down the mast. I
know that the rigging is probably on the slack side, particularily the
forestay (its at the end of its adjustment at the bottlescrew), would
this be the likely cause or should I be looking elsewhere?

I'd have your standing rigging tunned by someone familiar with the work.
You can buy tension testers.
As far as your 'turnbuckle'??....I read that they should be screwed in a
certain percentage of the length of the bolt. My modest 19 footer calls
for 3/8" . My rigging manual says "the exact amount of tensioning is a
matter of experience and personal preference"...but "should be increased
until the slack is reasonably tight, but not as tight as a drum".
I'm assuming you have the mast 'raked' forward/aft properly and is
'plumb' side to side.

bb September 17th 05 12:41 AM
On 16 Sep 2005 15:08:13 -0700, wrote:

I have been experiencing a problem when beating in moderate+ winds. My
foresail is a masthead rig(?)a large genoa & really 'bangs' when
sailing close to the wind, this in turn is transmitted down the mast. I
know that the rigging is probably on the slack side, particularily the
forestay (its at the end of its adjustment at the bottlescrew), would
this be the likely cause or should I be looking elsewhere?

Check for compression at the mast/mast step. If your rigging is at
the end of it's adjustment, and the rig is still lose, there's a
reasonable chance your mast has sunk, for whatever reason. Possibly
you just need to tighten the back stay a little more to get the head
stay tight.

bb

[email protected] September 17th 05 02:19 AM
That'll ruin yer day, finding the bottom end of your mast being an
anchor.

K. Smith September 17th 05 02:43 AM
wrote:
I have been experiencing a problem when beating in moderate+ winds. My
foresail is a masthead rig(?)a large genoa & really 'bangs' when
sailing close to the wind, this in turn is transmitted down the mast. I
know that the rigging is probably on the slack side, particularily the
forestay (its at the end of its adjustment at the bottlescrew), would
this be the likely cause or should I be looking elsewhere?



You don't emntion the backstay(s), assuming it has plenty of travel
left in the turnbuckle you han tighten the forestay with that, indeed
that's how most forestay tension is controlled.

You use the forestay to position the masthead, a small movement forward
or aft can change the handling (influencing falling off or rounding up
when close hauled, cruising boats can be also self steering into the
trade winds once the masthead position is tuned), then usually once
that's sorted you use the backstay (adjustment) to control forestay tension.

This has two benefits, the forestay need only be really right on the
wind & if the forward lowers are adjusted right, as you tighten the
backstay even with a masthead rig, you'll put a little aft bend into the
mast which has the effect of flattening the main, so it also performs
better to windward.

On modern glass production boats you will only get so much outright
"tension" (the hull has some movement) but it's still plenty for good on
the wind performance.

If your backstay is "adjustable" say hydraulic or a wheeled
turnbuckle??, get into the habit of letting a bit of tension off when
leaving the boat.

No matter how you try you'll not stop some forestay movement on
windward beats in open water, there's lots of forces going on. Don't
over tighten the rig.

Seems I recall a certain Ozzy america's cup boat that broke in two &
went down in less than a minute, by a combination of over zealous crew
pumping the backstay, rough water & a hull design way too light for the
job; oops:-)

K

[email protected] September 17th 05 07:54 AM

wrote:
I have been experiencing a problem when beating in moderate+ winds. My
foresail is a masthead rig(?)a large genoa & really 'bangs' when
sailing close to the wind, this in turn is transmitted down the mast. I
know that the rigging is probably on the slack side, particularily the
forestay (its at the end of its adjustment at the bottlescrew), would
this be the likely cause or should I be looking elsewhere?

There was some mast compression which I have repaired by replacing the
mast support beam. However I was unable to get the cabin top back to
its original shape so thats why I'm at the limits of adjustment. At the
end of the season I am going to put a block under the mast to raise it
to its original height which should allow me to adjust it to its
correct tension.
Would this explain the 'Bangibg' which really is quite extreme &
nothing that I've ever experienced before?


All times are GMT +1. The time now is 02:16 PM.

Powered by vBulletin® Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Copyright ©2004 - 2014 BoatBanter.com