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179 F'n Saint

About ProaSailor

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  1. ProaSailor

    bluewater multihulls

    Thank you. That gadget is only a "counter spring" to hold the hatch in any position, not a two axis hinge.
  2. ProaSailor

    bluewater multihulls

    Very nice boat! Am I seeing interior two-axis hinges on those hatches that open out? Great idea! Smaller than I would have expected but apparently they work. Could use two of them... Can those hinges be purchased separate from the hatch?
  3. He's an ultra-conservative rich boy mercenary with a very dubious public record. From the article @NeedAClew posted: For the sake of his crew, I hope this old saying doesn't apply to strange shipmates. “Misery acquaints a man with strange bedfellows.” -- The Tempest, by William Shakespeare
  4. Are you saying the entry names are a joke? Or trying to pull off a Jedi mind trick?
  5. Good eye. Knowing nothing more than those two owner names, I'd bet the answer to @mattyc's question is yes, definitely.
  6. ProaSailor

    Used cat market

    Dazcat 1295 - 42 feet, WEIGHT lightship: 5250kg (11,600 lbs.), max loaded: 7500kg (16,500 lbs.), "only" $613K "used" (a 2020 model?): Looks like it sails well. This is good video of a delivery trip in the U.K.
  7. ProaSailor

    Need ideas for a safer, better escape hatch

    100% agreement on both points! @he b gb suggested the oval solution that allows bringing the detached hatch aboard in post #59 and I modeled it in post #63. That single, simple, minor change satisfies 90% of my concerns with the design @boardhead presented. It has a bonus of increasing diameter of the opening by ~2.5 to ~3.5 inches in one direction. Might add a pair of keyway notches to help rotational alignment of the elliptical hatch. I would choose "I-beam" over inner disk to mount the inside handle that pulls on the center of the hatch.
  8. ProaSailor

    Need ideas for a safer, better escape hatch

    This discussion has nothing to do with engineers. Following your lead, it has degenerated into another SA pissing contest for skunks. So typical. Show us a video of someone actually using your hatch? And prove to me that the inner disk does a better job than a horizontal bar on the interior? Both pull the center of the outer disk (hatch), which I agree distributes load evenly to the gasket. It doesn't matter how the inner end is attached. The contribution of the inner disk pushing out on the hull, in effect "supporting" the gasket, is insignificant. The inner disk may look better than a horizontal bar but that's a cosmetic decision, not improved engineering.
  9. ProaSailor

    Need ideas for a safer, better escape hatch

    I keep telling you, the latch mechanism isn't shown yet. I picture a handle in the middle of the hatch, maybe looking something like this on the outside: What happens on the inside is unspecified so far... I've been trying to incorporate your pull-on-the-middle idea but failed so far. Honestly one of the simplest methods might be five or six linkages from a central ring out to dog clutches, jamming the hatch closed. Old school, updated. For fun.
  10. ProaSailor

    Need ideas for a safer, better escape hatch

    I'm picking shape dimensions out of thin air without knowing, as you do from experience, how to match size, shape and materials with expected strength (however strength is measured?). But so much can be learned by building CAD models, trying different sizes and pivot points and angles, looking for collisions while moving parts through their motions. The hatch bevel angle in this model, for example, needs to be ~33 degrees near the hinge to barely avoid colliding with the hull as it swings out, while the opposite side can be 15 degrees. Adding another 90 degree hinge at the end of the "arm" isn't too difficult but quickly shows that it must be "closed" first, before swinging the arm too far, to avoid two annoying collision scenarios. A linear linkage won't do either since "Axis #2" needs to return to zero before Axis #1 goes below ~30 degrees. Aligning 'Axis #1' for the "arm" with the hatch could be done in a factory by extending the blue "rabbet" ring to the red pivot supports, fusing them together with cut-outs for the swinging arm base. Not shown but will be included in future as it makes so accurate installation so much easier. The extended blue ring would become the base plate for 'Axis #1' (the primary hinge) with the major benefit of aligning the pivot axis correctly with the opening.
  11. ProaSailor

    Need ideas for a safer, better escape hatch

    This opening is 20 inches wide by 17.5 inches tall, the white pivot pin (1/2" diameter) in the red mounts is 18.3 inches long. The elliptical hinge arm is 7.2 inches "tall" by 1.6 inches thick with 1/2 inch of clearance under it, so 2.1 inches of width is lost to it. I have no idea how to build it, what materials and scantlings are appropriate, etc.
  12. ProaSailor

    Need ideas for a safer, better escape hatch

    What are you talking about? I haven't mentioned any latching mechanism yet, only a way to move the flush hatch up out of the recess in the hull while keeping it attached to the boat. I don't believe your inner disk contributes significantly to gasket clamping pressure though, if that's what you mean? Pulling the outer disk at its center can be done without an inner disk. But I hadn't said that yet, so what are you talking about? I can appreciate the elegance of your proven design, I just have some issues with it, as stated. To be clear, I wouldn't use it on my own boat. Obviously(!), nobody wants "disemboweling bracketry [and] finger severing pinch points" or leakage. But why get so bothered by me exploring a concept on this forum?
  13. ProaSailor

    Need ideas for a safer, better escape hatch

    Single "hinge" with minimal intrusion. Dark blue ring leaves 3/4" rabbet all around with 3/8" tubing (yellow) as gasket. A second hinge (not shown) to allow 90 degrees more rotation (180 degrees total) could be located where the arm attaches to the hatch, pinned or latched somehow at either zero (as shown) or 90 more degrees. Still missing details like latching mechanism, pivot rod support and the finer points like clearances, fillets, materials, etc. A concept, not a plan!
  14. ProaSailor

    Need ideas for a safer, better escape hatch

    I can imagine many things. I can imagine considerable difficulty dealing with your outer hatch thrashing around on a short tether because it can't be retrieved through the opening. I can imagine leaving my boat on a mooring in Hawaii and finding that someone has boarded it through the unlocked escape hatch. I can imagine refinements that allow 180 degrees of rotation instead of only ninety. I can imagine the door being removable once opened. I can imagine more secure variations (without the screw heads showing) of this flush two pin hinge idea for getting 180 degree rotation of the hatch: The animation was a quickie concept sketch, not a proposal. The "compromised gasket loading" is only in your mind. The full 3/4" rabbet for the gasket is shown only as a line in the animation but would be as before, as you have done, allowing for the hinge. Chill brah, read the thread title again, the key word being "ideas". Simplicity and light weight are always preferred, of course. Cheers.
  15. ProaSailor

    Need ideas for a safer, better escape hatch

    A mock-up sketch of a "hidden hinge", limited to 90 degrees rotation. Needs detail work. Instead of two "arms", it might be stronger to have just one long semi-cylinder arm... Maybe next year, Cheers.