Bimini Frame Designs

Questions & Answers
1

Hi All,
On the way home from the 2026 Rendezvous, Soave was gifted 20 miles of downwind sailing in 15-20 knot wind. We had following waves 4-6’. Perfect except for the 1.5 hours of torrential rain that came at the end of the run.

We did have a potentially dangerous failure of our bimini frame, so I’m starting to look at options to improve its durability and safety.

The below photo shows the frame in it’s folded position, which it was in when it failed. The failure occurred where the frame attaches to Soave’s pushpit. Luckily the frame pipe ( held by a single set screw ) slide out of the bracket receiver on both sides at once and the entire frame rotated forward and down over our heads. The cause is Soave’s mainsheet when eased to the full downwind position contacts the frame just above the point where I’ve used a sail-tie to temporarily prevent another failure. In 20 knot wind the tension on the mainsheet has to be close to 1K lbs especially when surfing off waves. The frame only deflects the mainsheet a few inches so the pressure exerted to the frame is a fraction of the full load.

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I’ve seen two approaches to managing interaction between bimini frame and mainsheet.

  • Option 1 - Allow mainsheet to come in contact with the aft bimini frame support, but reinforce the frame so it can handle the load. These frames tend to offer some protection to the helmsman while jibing but care must be taken to be certain the mainsheet can’t hook any part of the frame.
  • Option 2 - Support the bimini from forward of it’s center bar and eliminate the need for aft support. Frames that I’ve seen using this approach feel less solid, probably because the forward brace can’t go too far forward without impeding access to the cockpit.

I’m in no rush, but eventually I’d like to resolve what I consider to be a design flaw for Soave’s bimini. Please point out the options I’ve missed and also post pictures if you know of a boat that has addressed this issue in a simple but effective way.

Speaking of downwind sailing, at the Rendezvous Win Sanford gave a great presentation on preparing his Nonsuch 33 ( Kitty Hawk ) for the Bermuda race ( he won his division in '91 ). He explained the Hudson River Jib in a way that gave me enough confidence to give it a try. It worked ! I’m a fan of both the Hudson River Jib and Win for the his creativity when preparing Kitty Hawk for offshore sailing. No, I’m not planning to take Soave offshore, but I’d like to coastal cruise with confidence that Soave could hold her own in a blow.

I highly recommend participating in any in-person Nonsuch events you can get to… Discourse is good for exchanging ideas, but you can’t beat face-2-face interaction.

Next event on LIS is Labor Day weekend, Port Jervis, NY.

Thanks,
Rob…

2

Rob,
CHICKEN jibe every time. You were not in a race that could justify a Hudson River Jibe. I scared the bejesus out of my kids and I wasn’t even trying to jibe.
Just sayin. Or use that power winch to haul the sheet in.
Brian

3

There’s a company which makes struts that fold but lock into straightline position for purposes of reinforcing folding dodger and bimini frames.

You might want to take a look at whether adding some of these, positioned to counter the upwards and forward forces of the mainsheet. The same outfit also sells sleeves that go over the articulation point to reinforce it and keep it from folding when not wanted.

I can’t really tell from the picture, but I’m guessing that the outermost frame piece attached to the strut that pulled out was the actual culprit. Another low-cost revision might be to put a brace running between that piece and the horizontal part of the stanchion. That’d require a few fork and post hinges, a strut with eyes on each end, and a detachable locking pin. That kind of set-up would provide some directional counterforce against the pull-out you encountered.

There are some 50 previous threads on Hudson River Gybe vs. the pejoratively named Chicken Jibe, better described as the Catboat Jibe (or, as the original Nonsuch sailmaker, Ed Botterell, suggested, the, “SAG: Stay Alive Gybe”). It’s been a religious debate as long as there have been Nonsuches. I’d like to split the difference by citing Botterell’s advice that certain maneuvers are best performed only by experienced sailors who have justified confidence in their skills.

That said, maybe jibing is a topic we should split into a different thread and keep this one to biminis.

Can’t beat face-to-face interactions, I agree. (Although… working in DC before I retired involved a lot of face to two-faced interactions. Those aren’t as fun.)

-- Bob