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Author: Jason Cosler
Subject: Uppers Tension, Rake, Pre-bend etc.
Info: (3278 views) Posted: Saturday 2-5-05 07:36:02 AM
Been several threads on rigging over the years, but most of them are off the board now...and the offseason is a good time for a contemplation, so bear with, here goes:

The trend on most boats over the years has been to maximize rake. I certainly don't understand all of the reasons behind that theory, but I know that there's a lot about vertical profile of the headsail and, perhaps most importantly, pre-bend in the mast and the ability to control twist in the main leech. But on a boat such as the Express without swept spreaders and without the ability to block the mast partner (i.e. move the butt), there isn't any way, in theory, to create pre-bend. So, again in theory, how does a sailmaker build any luff curve into the main? Two ways, I guess. One, rake the mast forward a bit. The shouds are located ever-so-slightly aft, so rake the mast forward and you're creating some sweep to the rig (probably need slightly swept spreader bars to really accomplish this). Don't think I like this option. The second option would be to forget pre-bend all together and assume that in light-to-medium conditions, the backstay will have to be pulled on a good bit and the aft-lowers slacked off. Problem there is headstay tension (even with the aft-lowers off, the headstay will probably be too tight, esp in chop) and the fact that, due to the bendy mast section above the hounds, you probably don't get a favorable luff curve, you just twist the top batten off way more than you should.

Academic? Probably to y'all on the west coast who want lots of rake and lots of forestay tension and could care about a fuller luff in the main, but over here in the other bay, the boat is just so sticky in light-to-medium conditions against other boats. Last year I got a new forestay from Ballanger. He said they started making them longer at about halfway through the original production and it was longer than our original one by a couple of inches. So the question is (and maybe you guys in Detroit have a better feel for this) is more rake really where it's at for non-jib conditions? Frankly, I think we were faster and pointed about the same with less rake. I should note that our main is a Quantum Fusion with 2 seasons on it and it was cut around the rake number the Richmond loft has been using (30'-6" I think), but the first season with sailed with a lot less than that due to the old forestay being too short. However, the boat flew. We went from deep mid-fleet to being in the money on just about every race. Then came the new forestay, more rake and less silver. Probably need a new genoa, but still. Any mid-winter thoughts?

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