Ideas on Non-OD Compliant PHRF mods for stiffness??
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I may draw some ire for this… but I am considering taking my boat (#246) out of OD compliance in the interest of stiffening the boat as much as possible. It is clear that the Chesapeake O-30 fleet is done as far as one-design competition goes with only two active racing boats on the entire bay. As a result all I do is PHRF racing with the boat and I get my OD fix with J-24’s in Annapolis. Stiffness means pointing ability and when all you race are frac rigs that can out point you every degree matters in terms of holding your lane and being in good position on the course. Sailing her as fast as possible among like boats isn’t always an option in a big PHRF fleet. So I need more stiffness.
So I was wondering what ideas people may have regarding gaining the most stiffness with the least added weight as a DIY job for someone who is decent with construction and fiberglass. Last year I rebuilt the mast step and stringers well beyond the original design (though still OD legal) and this improved things dramatically but was a huge project. This year I am considering connecting the cabinetry to the v-birth to make a continuous instillation. I know a considerable amount of the boats rigidity actually comes from the internal cabinetry and tabbing so I thought this might improve things for little extra weight. I have also thought about a ring frame at the bulkheads.
Any other ideas floating around out there?? Any and all ideas welcome.
-Jon
Well it would help to glass the cockpit to the hull with sidewalls, full ring chain plate bulkhead, taller stringers. I think there are few boats that had a major redoux done.
There is one in CA with taller mast and longer keel, any one remembers the name?I just cut the cockpit out of my boat and in process of putting in a new one. I can tell you where the weakness is…Support the companionway under the pit with a bulkhead like the one mid cockpit. The cabin top is totally supported by the front of the cockpit, which was unsupported in my inboard boat.
I don’t think the boat flexes that much. Do you have a turnbuckle on the front of the mast up to a deck attachment? That pulls/holds the deck down..which keeps the hull sides out.
Bruce, my boat has a 2×4 that is glassed in that is about a foot back from the companion way wall that supports the cockpit sole. I suspect that the way it is arranged (not centered) it is there also to attach the outboard so as to not have it jump around.
Lilya,
Fast company has this same 2×4, off center just aft of companion way. Never thought to clap outboard there. Oh, we don’t have one…My understanding is that post aft of the pit below the cockpit was indeed designed to hold the outboard in place. Though I don’t think it’s an acceptable place to have that weight while racing. I strap mine to the base of the mast.
I also have the 2 x 4. Figured it was to stabilize the cockpit. I have a removable 2 x 8 athwartship between the fore and aft bulkheads, far enough aft of the mast to fit the head of the outboard. Nice and low, right over the keel.
Jim,
I am strapping a cork pfd to that post for this summer’s journey to Nawiliwili. As for the outboard, mine’s in the livingroom next to the liferaft end table. Actually I raced with someone who did that with his outboard – so I assumed that was what that post was for.I can tell you with a bunch of assurance: the toe rails contribute zero to stiffness. At best they fasten the deck/hull seam. None of my fasteners were tight enough to consider that ‘the fastener’ of that seam. It is resined together and tight everywhere except one common place…mid windows on both sides. The interior glass wasn’t broken, so it appears for us winter freeze people, the deck had come loose due to water/ice heave. My deck is now glassed all the way to the chainplates, so zero change of a repeat. Toe rails..not going back on except forward as required by ORR.
If you want to stiffen the boat: Add a cable from the deck to the mast step. Tighten.
PS: PHRF does not care about modifications that are related to stiffness. They should be reported, but don’t fear any rating change.
Hull shape; mast changes; sail changes; weight increase/decrease..those are mods that change PHRF.
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