Bowsprit for the Altair

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thinwater
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Bowsprit for the Altair

Post by thinwater »

Has anyone done this?

I'm not interested in a screacher; I have a 150% genoa that provide nice balance and is all she really needs or want up wind. This is only for a chute.

I cannot use the pole-type that Sandy used on his 36; there is a gull striker in the way. I wouldn't want it over the tramp anyway.

I can't see how you secure the water stays low; on the starboard side the crash tank comes quite high.

So what I am toying with, after having spent all day at the Annapolis Boat Show today, is rigging the pole more as it would be done on a Gunboat or beach cat (I had one like this):
* Stays to the fore beam ends for lateral loads.
* Extend the gullstriker downwards (dolphin striker) ~ 14" and run a stay from the tip of the pole, over his striker, to an anchor on the bottom of the bridge deck. This will take the vertical loads.
* The pole will only be 3-4 feet; I do not want to get a new chute, and I think moving the tack forward 3' will actually improve the shape (leach is too tight reaching).
* A lashing to the top of the gull striker will hold it up; this is common practice.
* The downhaul will be 2:1; generally this is adjusted with the halyard winch if under load.
* It will probably angle up slightly.
* I'm not too concerned about the aft load on the fore beam for a chute, but I will consider that in all calculations. The load for a screacher is MUCH higher, whereas I know that the tack line tension only slightly exceeds what I can hand hold with 2:1 purchase (I often adjust the bridle underway). I can't see it exceeding 300#, and much of that is lateral. I doubt the dolphin stay tension would exceed 600 pounds. I could install a compression strut, but I hate adding complexity, weight, and anything that messes up a nice tramp. I could also make it A-frame, which eliminates the aft loading and the lateral stays... but perhaps that is ugly.
* I could simply take the waterstays as low as I can, which would take a lot of load off the dolphin stay. I do like the idea of keeping the waterstays out of the water. I dislike the fact that loading on the 3 stays becomes structurally indeterminant in some laodings (minor).

I will figure some way of making it foldable, but I very rarely take a slip where anyone is going to care about some thing that only protrudes about 2' past the anchor.

Thoughts? Speed is one reason. Better reaching trim is another. One the main reasons is easier jibing (fewer hourglasses); yes, I can simply lower the squeezer, jibe, and re-hoist, but that is inelegant... though quite practical when single handing.
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