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Old 27-05-2016, 23:28   #16
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Location: mackay, queensland. australia
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Re: Bowsprit length vs. exact centerline?

the take off point on your spit needs to be in the right place. the lump of material holding that is merely structural and cosmetic / you can adjust the sail foot across port or starboard to fine tune once the sail starts to stretch a bit/ may be different in different conditions/ we carry 5 spinnakers and a small loose block hanging off the top link on the bobstay chain/ occasionally that's used to fly a smaller spinnaker to allow for more adjustment/ usually after feeling the boat is trimmed properly the wind changes. the bowspit carries 3 small ronstan furlers /for straight downwind we pole out no.1 and no.2 headsails and found they furl with the poles on if we have to/ p.s the bowspit is a bit hard on the forhead of people walking along pontoons in marinas. take care of the overhang when parked up bow in. best of luck with your sailing project
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Old 28-05-2016, 00:47   #17
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Re: Bowsprit length vs. exact centerline?

Quote:
Originally Posted by Copprhead View Post
Uncivilized: The cleats that hold the aft end are in a predetermined position, as there are aluminum plates laminated in deck and those points. So they can't change. And the ring is done so the sprit doesn't collide with the roll bar of the anchor. Leaves only length to be varied.

I measured, it's 8 cm to starboard. I think I'll give it a try like that since nobody yelled 'you gonna break the rigg and sink the boat'. If it's no good, I can still make the sprit shorter.
I wouldn't worry about 8cm, as that little offset vs. the length of you J is nothing. I'd be surprised if it was more than a degree or two. And plenty of halyards are offset more than that, at the masthead.
So don't sweat it.


FYI, you Can move such cleats around. It just means that you'd need to ensure that there's enough solid core in the deck, wherever you decide to re-mount them. Even if it involves some deck re-coring.
Which is done all the time.
Then add some monster sized backing plates, & poof, new positions.

It's a weekend job, at most. Including letting the epoxy cure. And the above is how most cleats are mounted to begin with.
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Old 28-05-2016, 03:02   #18
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Re: Bowsprit length vs. exact centerline?

Quote:
Originally Posted by Copprhead View Post
Uncivilized: The cleats that hold the aft end are in a predetermined position, as there are aluminum plates laminated in deck and those points. So they can't change. And the ring is done so the sprit doesn't collide with the roll bar of the anchor. Leaves only length to be varied.

I measured, it's 8 cm to starboard. I think I'll give it a try like that since nobody yelled 'you gonna break the rigg and sink the boat'. If it's no good, I can still make the sprit shorter.
What do you mean by "cleats"

Selden uses a folding D-padeye for supporting the aft end of the pole.




Quote:
Originally Posted by UNCIVILIZED View Post
Then add some monster sized backing plates, & poof, new positions.
I don't believe that it's necessary to go to to the trouble of large backing plates for the pad eye. The forces on the pad eye are lateral, not vertical, as the aft end of the pole is pushed into the deck. So just using bolts with washers should be sufficient.
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Old 28-05-2016, 10:28   #19
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Re: Bowsprit length vs. exact centerline?

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Originally Posted by hoppy View Post
What do you mean by "cleats"

Selden uses a folding D-padeye for supporting the aft end of the pole.





I don't believe that it's necessary to go to to the trouble of large backing plates for the pad eye. The forces on the pad eye are lateral, not vertical, as the aft end of the pole is pushed into the deck. So just using bolts with washers should be sufficient.
I'm 90-some% certain, that when he says cleats, he's referring to his bow cleats. As on a good number of designs out there, when they're laying up the boat, they laminate aluminum plate into the deck where high load hardware is to be mounted. And then, once the deck's "done", they drill through the glass, tap the aluminum, & bolt on the cleats.

I can't says as I'm a fan of it, but it's how many builders do things.

Though if he's just mounting a padeye, such as in your image. Then the more significant issues will be where the downwards compression, & side loads get resolved. Both via the boat's deck, & internal structure.
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Old 28-05-2016, 13:09   #20
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Re: Bowsprit length vs. exact centerline?

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Originally Posted by UNCIVILIZED View Post
Though if he's just mounting a padeye, such as in your image. Then the more significant issues will be where the downwards compression, & side loads get resolved. Both via the boat's deck, & internal structure.
The OP did say its a Selden bowsprit, so there should be a padeye.

Keeping the pole the full length will lessen the downwards compression, so it is best to not cut the pole if the OP can avoid it.
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