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Question. I've just posted a picture of my current forestay setup. I have separated forestay tension from jib luff tension with a self-cleating 6:1 block tensioning the forestay, and a 4:1 purchase tension the jib luff. This works perfectly going to weather. I can haul down on the 6:1 until my whole rig is very tight - no sag on the lee shrouds. With the rig tight much less tension is required on the jib downhaul to get a tight luff. Setup this way, the boat goes to weather in a stiff breeze like a steam train. I'd appreciate any feedback on any possible downside to setting up the rig this way - it puts much more tension on the rig than is usual on a Wharram? On the other hand, the Wharram design (rig, beams and hulls) is over-engineered and I think it should be more than strong enough to handle the loads. I have been using this setup for about a year including in winds up to 30 knots. Comments appreciated.

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Roger,

I'd say it's an excellent setup. Being able to dial in or out on the forestay tension is a big plus in my book!  With your level of attention, you will notice if the boat complains long before any thing breaks. I would think that reducing the shock loading on the rig would actually help it live longer.

Kim

Hi Kim,

My thinking too. I have not noticed any squeaks or noises (or other complaints) from the boat - if anything it is quieter because everything is tight.

I used this on my Hinemoa (though use turns without blocks on the forestay) and it worked a treat. Much easier to tension the jib at the foot than via the halyard and also easier to get the mast straight as you are applying the tension in a single central point.  Our current boat has a furler and we can not use this technique and I have found it much harder to set up the rig tension.

Roger, do you lead the tail of the forestay purchase to your cockpit?  And, what sort of cleat are you using for it? I was looking at the tackle for different boom vang setups, and using a fiddle block with a becket and a cam cleat is how most of the vangs deal with the tail. I can't make it out in your picture, but does your triple-block have the cam cleat?

Doesn't this change mast rake?

Did you notice a change in the way she comes around when tacking?

Hi Ralf, I would think that as long as the shrouds are the proper length, the rake will be fine. 

Hi Ralf,

Kim's right. All it does is tension the forestay against the shrouds. When tightened it makes the whole rig tight. Off the wind the rig can be slackened right off for a better sail shape. In theory, one could slacken the rig and tighten the mainsheet to increase rake going to weather. This is a technique used on the Hobie 16, but I think its particular to the unique characteristics of the H14 and H16 (I haven't tried it on the Wharram).

Hi Kim,

I use the little 20mm Ronstan triple block with cleat for the forestay purchase, so I have to go forward to change the tension. The 4:1 luff tension cleats on the front beam, but I'm going to change that to a fiddle block with cleat, because it still pulls the forestay back as it is.

kim whitmyre said:

Roger, do you lead the tail of the forestay purchase to your cockpit?  And, what sort of cleat are you using for it? I was looking at the tackle for different boom vang setups, and using a fiddle block with a becket and a cam cleat is how most of the vangs deal with the tail. I can't make it out in your picture, but does your triple-block have the cam cleat?

Having to go forward is not bad on these boats. . .The increase in friction from leading the tail through all sorts of fairleads, direction changes, etc., can be substantial. I did run my jib downhaul's tail under the front beam, under the net, to the mast beam using fairleads to a cam cleat near the mast foot, in order to keep it from tripping me or crew. Wow, say that three times fast! ;~) But, like you, I feel the purchase on the forestay should stay in line with the forestay for best effect.

I also found it was not a problem going forward to tension the jib luff.  I used a triple top block and a double block and cleat at the other end, the cleat was a V rather than a cam and worked fine.  I did contemplate leading the line back but came to the same conclusions as Kim that it created friction and a trip hazard so did not bother.

I never felt the need for the forestay to be adjustable; I used multiple turns put on progressively and a handy billy (or just me) pulling on the tail to get the tension in when I put the mast up and that was that for the season.

measure the amount of forstay sag ..string line and an aproximatometer.. then have your sailmaker recut a hollow luff jib to suit fit a couple of tell tales and away you go.. windward performance is relative .. my racing cat has no jib and is better to windward than sloop rigged racing cats... wharrams have similar sailing characteristics to the early hobie cats with no boards   sail em free and fast to climb to windward otherwise you just stall out the hulls and rudders

Hi Steve,

Thanks for the feedback. This sounds like a good solution too, and I'm guessing that it works really well in light air. But I still believe that there is no substitute for a tight rig to windward - at least when it is blowing. This is true even if you are footing free (relative to another boat with a loose forestay), the boat with the tighter rig is going to be more efficient to weather. If you have a tight rig you can work to depower the sail by flattening it with downhaul and sheet tension. If the forestay is loose, the sail will remain full and over-powered no matter how tight you sheet it in. It may have more relevance here in SF Bay in that it is blowing 20 knots most days by the afternoon.

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