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delevi wrote:I think the SF700 is the way to go, for the reasons stated. I'm getting close to pulling the trigger on a genoa, and would strongly consider the SF 700 to have the ability to change between jib & genny. I still think that getting uv protection is a good idea, just to save some time, not having to take the sail down every time. I'm not too enthused about dual forestays. Just think it's probably more trouble than it's worth, with additional lines to deal with, more hassle with rig/derig and carrying the weight of and extra sail/furler on that second forestay i.e. additional windage and weight aloft.. not a good thing on a windy day.

Question for those of you who researched the sf700. What's the deal with sanpping it on your forestay? Is it a two piece luff that snaps in place? If so, I'm a bit concerned about its overall strenght vs a one piece desing. Not sure what the benefit would be, since sliding the forestay cable into the furling luff is a one-time deal. Perhaps someone can enlighten me.

Cheers,
Leon

OK, so what is the real deal

Delevi wrote:
Just for the record, I use the CDI as well. I don't have a problem with luff tension as many have noted to be the issue w/ CDI's internal halyard. You can create luff tension by tightening the tack. One can create a 3:1 purchase by looping a line from the jib tack and the schackle of the furler. It is static tension, so it doesn't ever get relieved unless the sail comes off the furler. Honestly, I don't think I would mess with it, even if I had a furler w/ external halyard. Luff tension should be tight but not too tight. Beyond that, you're at the mercy of the furling foil's shape. This would happen on any furler and the only way to control it is with running backstays. The SF700 sounds like an excellent unit but from looking at a piece of the luff at a boat show, my hunch is that it isn't quite as flexible as they make it out to be. Certainly less flexible than the CDI, which may present a problem for rigging/de-rigging. I'm also a bit concerned with some of Mike's comments about all the additional hardware and how parts can get lost in the drink. The one major disadvantage to the CDI, and therefore a huge advantage to SF700 is swapping sails. Major PITA on the CDI. I'm getting ready to pull the trigger on a pentex genoa from Kelly Hanson. One thing that will be important for me is the ability to change from genny to jib. I'll try to make a workaround solution on the CDI, perhaps implementing different shackles, and possibly a small block & tackle system w/ jam cleat at the tack. Also plan on spraying the luff w/ sailcoat. I'll post progress as things develop.

A Furling system…with its windage and weight aloft ‘increases’ the unavoidable forestay sag, which adds to the unavoidable headsail deep draft, even more when reefed.

Those tiny ‘CDI’-shackles with tiny little pins…..cheap stuff….

Delevi wrote:
They Theirs I must give credit where credit is due. I had a chat with Jeff at Arena Yacht Sales (on a different topic,) who in my book is a Mac & overall sailing expert. He is a very experienced and knowledgeable sailor & pilot, and knows the Mac inside out. I asked about a hanked jib vs RF. He concurred with your point that the hanked jib will outperform the RF jib every time, due to the sag in the forestay. The weight, though not much, just makes a huge difference and it doesn't matter how tight your rig is. The problem can be significantly alleviated with a backstay, however, which will narrow the performance gap, but the hanks still get the edge.

Halyard tension increases luff tension which flattens the foresail and pulls the draft forward. The Jib Halyard …like you said…not too tight or too loose… changes with point of sail and conditions… it is ‘NOT’ a set it once and good for all sailing conditions

Unavoidable CDI Furler Headstay Sag




we can see a little luff… but cannot tell if there is any sagging?

They Theirs wrote:Surely were aware of a furlers harmful weight aloft and significant effect on the headsail shape and performance,
further compromising a powersailor well known problems sailing to weather.

Two Years ago….no running back or self tending jib

Delevi wrote:
They Theirs I must give credit where credit is due. I had a chat with Jeff at Arena Yacht Sales (on a different topic,) who in my book is a Mac & overall sailing expert. He is a very experienced and knowledgeable sailor & pilot, and knows the Mac inside out. I asked about a hanked jib vs RF. He concurred with your point that the hanked jib will outperform the RF jib every time, due to the sag in the forestay. The weight, though not much, just makes a huge difference and it doesn't matter how tight your rig is. The problem can be significantly alleviated with a backstay, however, which will narrow the performance gap, but the hanks still get the edge.

Halyard tension increases luff tension which flattens the foresail and pulls the draft forward. The Jib Halyard …like you said…not too tight or too loose… changes with point of sail and conditions… it is ‘NOT’ a set it once and good for all sailing conditions

Unavoidable CDI Furler Headstay Sag




we can see a little luff… but cannot tell if there is any sagging?

Delevi Posted:
Funny thing is the forestay still has plenty of bounce. I'm sure the cable is tight, but the furled jib must really weigh more than my old stock jib. I suppose any furler will have some play as well, since... well it has to furl. I'll see how she sails this weekend. I'm wondering if the 1/8" forestay cable is too light for my heavier RF jib.

The reason I did this is to get the forestay tight. My new jib has been experience much flutter, even with the cars all the way aft. I end up having to sheet it much harder than needed to get rid of the flutter. Having talked to the sailmaker, the advice I got was to tighten the furler halyard, take up some leech and foot line and tighten up the forestay. I did all this, but the only way to get the forestay tighter would be to tighten the upper shrouds, since my turnbuckle was already cranked down to the max to remove mast rake.

Hopefully this rig with enough running backstay tension and having tightened up the furling halayard on the jib as well as the leech & foot lines will eliminate the flutter.

I think the consesus is that the jib is superior upwind and on every other point of sail in wind seeds 12 knts+ thus, overall is the better sail to have

I feel like I have just about done that, but sure didn't buy my boat bare. Around $35k out the door, and probably another $10k in sails, keel, rudders, hardware and other goodies. So that's $45k for a supped up Mac Oh yeah, that's $45k without any canvas and no autopilot.

Now me thats a different matter I DO RULE THE ROOST , and I'll prove it very shortly