Tips - Forestay Tension Tips

Forestay Tensioning Tips from George Carter

The following was posted on the chat site and is re-posted here:

Posted: Tue Feb 03, 2009 2:18 am Post subject: Re: Forestay tension in a blow

Posting By Jim Coleman:

Jim Coleman wrote: Hello Everyone and a Happy New Year. During my 1st year sailing the Sprint I have got on well sailing it with the loose set up as it was when I bought it from a very good Sprint 15 sailor; ie, 3rd hole down, a loose forestay, and mainsheet blocks going block to block in the middle with a strong pull when on shore. When I sailed with this set up in a few strong winds I was well on the pace in a straight line, although dreadful through the tacks, which I will work on. But it seemed to make sense to use the rig tensions for stronger winds in the “Tips” articles "Sailing in a Blow" by George Carter and "Stay Tooned" by Paul Smith. So in the last two F5/F6 outings sailing Unarig I set the shrouds (not quite) to the tension recommended by them, ie “…to the point where it is difficult to deflect the shrouds inwards by pushing with your finger ends….” However with that set up I found on the beat that it was very difficult to get the boat to accelerate. If I set traveller well low and bore away to get speed it took me miles off the point, and velocity made good (Vmg) was poor. The alternative was to keep the traveller in a bit, accept the lower speed and point up, as that seemed to give reasonable Vmg. Is that the way to go? On the reaches and runs I found the stiff set up was very good. I must admit I liked the loose set up on the beat and will go back to it if necessary.

But do the articles by George and Paul refer to Unarig and/orSport mode or both? No particular mode is mentioned in the articles. And can someone please enlighten me about sailing on the beat with the stiffer rig. I should add that weight is not the problem as I’m about 86 kilos in the kit and I know a few lightweights who go very fast using the stiff set up.

Answer to the above posting by George:

Hi Jim, just thought I would reply to this. My setting of the rig tension is very straightforward. My shrouds are standard length from Steve Sawford. My forestay was shortened to allow a rope to be used to adjust the tension at the bottom. I tighten the forestay rope to have the maximum tension while still allowing the mast to rotate by the wind. In light winds this means that it should be easy to rotate until 90 deg, only then do the shrouds get tight. It is very important that the wind can fully rotate the mast (almost to 90 deg) upwind. In medium winds, then the rig should get tight just before 90 deg and in strong winds then the rig gets tight quite a bit before 90 deg (but with a fair bit of effort I still can rotate the mast 90 deg by hand). In strong winds the rig will feel quite tight when you push and pull the bridle wires.

This is all very important to get right as the trick to going fast upwind in a blow is to let the traveller off, sometimes all the way, but have the sheet very tight. Most people have the traveller in too tight and the sheet too loose. If your rig is too loose you can't get the sheet tight enough before the main goes block to block. This is the reason I never move my mast back as some do in strong winds. You simply cannot get the main in tight enough. I never change the position of my shrouds ) 3rd hole from top.

When sprinting with the jib and trapeze I use tighter rig settings to avoid excessive jib luff sag offwind (although I don't think this affects speed very much - in fact in the Albacore you let the rig tension off on the reach and runs specifically to achieve sag), and as in medium winds the rig can sometimes flop towards you when the wind dies upwind and you are on the wire. So I use more rig tension when sprinting. When buying new shrouds always always compare the length of the old ones against the new ones using two screwdrivers. Then you are confident that there are no differences.

Hope this helps George