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  • Hey all,
    Some more new catamaran sailor questions here. First, I made up some webbing to hold my righting line to the dolphin striker. A few grommets to tie it to the dolphin striker, and some velcro to hold the loops of rope.
    https://www.thebeachcats.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=134944&g2_serialNumber=3

    As I've been looking around the web, I initially thought the righting line should be tied to a front corner and then routed over the up hull. But then I've seen some references to tying the righting line to the dolphin striker. Is the dolphin striker strong enough for that? It would give me more effective rope length. This is what I currently have:
    https://www.thebeachcats.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=134945&g2_serialNumber=3

    With this setup I'd have to untie the bowline on the up hull and then pull it through. If I was tied to the dolphin striker I'd just have to undo the velcro and pull it through.

    --
    Bryan in Poplar Grove, IL
    Supercat 17, unknown year. Future project
    Hobie 16, 1977 - died a spectacular death https://youtu.be/Y7O22bp2MVA
    Hobie 16, 1978 - current boat
    --
  • You can really overthink this one. You will have some mechanical advantage by throwing the line over the hull. A coil of line tied to the mast step is simple and all you have to do is stand on the hull and throw it over. Perhaps make it long enough to where you can tie it around your waist and leave your hands free to use a water bag. There are more elaborate ways. Whatever works. Think fast and efficient.

    --
    Bill Townsend
    G-Cat 5.0
    Sarasota
    --
  • I second the risk-of-overthinking statement. First, tying anything to the dolphin striker isn't a great idea. You're not likely to yank it off-center, but who needs the risk? Also, the "effective" length of the rope is really just the portion between you and the upper hull - where on the boat it's tied off doesn't matter. My preference (in simple righting lines) has always been to leave it tied to the fore crossbeam on both sides (like you've done here) so I only have to untie the lower and throw it over. Nothing wrong with having the velcro strap there to keep the excess length in order.

    --
    Southern Alberta and all over the damn place.
    *
    1981 SuperCat 20 "Roberts' Rockets"
    1983 SuperCat 19
    TriFoiler #23 "Unfair Advantage"
    Mystere 17
    Unicorn A-Class (probably made by Trowbridge) that I couldn't resist rescuing at auction.
    H18 & Zygal (classic) Tornado - stolen and destroyed - very unpleasant story.
    Invitation and Mistral and Sunflower and windsurfers w/ Harken hydrofoils and god knows what else...
    --
  • dup



    Edited by MN3 on Jun 21, 2021 - 03:12 PM.
  • IMHO you should tie NOTHING to the striker
    you risk ..... a lot
    that is a wet spot that will forever get hit with a lot of water and energy when the wind picks up. you better have a great method of lashing your line but that is a tough spot to store line, or gear

    if it is line tied to your striker, it could get loose and drag

    it could snag on something you may sail over you are rising your striker / day / week

    Or you could have a human error and demast. If your righting line is tied to a striker and somehow snagged on the mast ... you could pull your boat apart.

    I have a 25' (total guess) of easy to handle, non absorbing line in my tramp pocket (dynema blend) - I would tie to my bast ball in a flip and i have a water bag so i add a small loop to hang a full water bag as needed - with crew it's not needed. on my 6.0 i carry 2 righting bags and that same righting line (also used to step/lower the mast - it is attached to the forestay for someone to hold/assist

    sans my wings i would have a harness on (maybe) and would/could add a loop (as needed) for my harness hook

    practice flipping and righting your cat a few times in mild conditions so you have it all worked out when it happens unintended
  • If the line accidentally pulls the dolphin striker from the tip, yes it can bend it and if you don’t realize it might produce a disaster. I loop it around the front beam with the dolphin striker in between, so it’s secured
    side to side and up and down. to store it I sewed a pocket under the tramp.



    Edited by Andinista on Jun 21, 2021 - 04:29 PM.
  • I tie mine to the dolphin stiker. Then I lead the line aft, thread it through one of the center tramp laces and lead it back forward and tie it off to itself with a few half hitches. Never had an issue with it coming undone and when I need it, I just untie the half hitches, yank it free, and toss it over the upper hull for use.

    sm
  • Nothing wrong with tying to DS. Both Nacras & H18 are tired to DS, & we manage to use those lines every year!
    As MN3 said, the line below the ramp might cause problems...so keep it all on top.
    Everyone of mine, the line stays attached to the bag, on TOP of the tramp. The Nacras have a grommet near the mast for the line to go through. Push the line through the grommet, tie to the DS. The line will stay high on the DS, no one is strong enough to bend it with only an inch or two of leverage.
    The H18, tied to DS then up over crossbar
    I WOULD NOT EVER tie the line to my body. When the cat comes up, & possibly takes off, you do not want to be tied to that line.
    Wait til you get your boat in the water. Flip it in controlled conditions. Then figure out how much line you need, & where you should tie your righting bag to the line.
    Now, when actually needed, stand on the hull, release the bag & line, ( I Velcro strap mine to a hiking strap), toss it over the hull, reach down & fill the bag, stand up, place the bag over one shoulder, & hike out. Place a couple of knots where you will be grabbing the line, it’s too hard to hold a bare line. You can also place the line onto your harness hook, a big enough knot will act as a stopper, taking the strain, & leaving your hands free. As the boat comes up, just grad the next knot up, that will allow the line to fall off your hook.
    I used to use a thick line for the entire length. One day I spotted an unused hiking line from an old windsurfer.
    They are only about 5’ long, with golf ball sized nubs on the line for handholds.
    I use a thin line from the DS for most of the required length, using the windsurf line where handgrip is required.

    --
    Hobie 18 Magnum
    Dart 15
    Mystere 6.0XL Sold Was a handful solo
    Nacra 5.7
    Nacra 5.0
    Bombardier Invitation (Now officially DEAD)
    Various other Dock cluttering WaterCrap
    --
  • Bad juju tying things to the DS.

    Tossing the line over the hull makes it easier on your arms, but it doesn't _actually_ give you mechanical / leverage advantage. So what I do is I set up a "Hawaiian system bungee line" from murrays, routed from the crossbeam corner, and I splice in a small loop in _just_ the right place for my trapeze hook.

    Measuring the right place requires having the boat on its side on land, and experimenting a bit. Got to do it per side!

    Once the hard work on land is done, the capsize recovery is a breeze. Get on the hull, grab the bungee line, find the loop, hook it on your trapeze and hang, arms stretched above/behind your head. Max leverage, min effort, no time wasted...
  • I give a second use to the righting line, which also justifies to loop it around the front beam: when the boat is on the trailer i tie that line to a cross bar of the trailer, about 40 cm back from the front beam or so. It seems like a good support additional to the straps around the hulls, to keep it from sliding forward. I am 2 blocks away from the launching point and for that distante i don’t strap the hulls, just use the righting line pulling back and down and the winch pulling forward. Very simple and strong enough.
  • A couple of vids from Joe at JoyRider TV, might help

    https://www.youtube.com/watch?v=4clZ9hLGUgQ
    https://www.youtube.com/watch?v=oHIcLc7pssc



    Edited by johnoau on Jun 23, 2021 - 06:02 PM.

    --
    1335 XTSea Nacra 5.8 NA
    605 Nacra 4.5
    Cleveland Yacht Club
    Brisbane, AU
    --
  • I've watched a bunch of Joyrider TV. Seems Joe is a fan of using the dolphin striker.

    I'm concluding that I don't like having the line secured with that velcro strap. I'm more worried about it coming loose while trailering than while sailing.

    --
    Bryan in Poplar Grove, IL
    Supercat 17, unknown year. Future project
    Hobie 16, 1977 - died a spectacular death https://youtu.be/Y7O22bp2MVA
    Hobie 16, 1978 - current boat
    --
  • QuoteTossing the line over the hull makes it easier on your arms, but it doesn't _actually_ give you mechanical / leverage advantage.
    I don't quite understand the geometry of this, goes against conventional thinking. I once had two righting lines on an 18 ft cat, each one was secured under the tramp at the corners and standing on the hull when we did capsize the line was right there. I did not throw it over the hull but with 2 of us the boat righted with ease.

    --
    Bill Townsend
    G-Cat 5.0
    Sarasota
    --
  • QuoteI don't quite understand the geometry of this,


    https://www.thebeachcats.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=134961&g2_serialNumber=4

    https://www.catsailor.com…eads.php/topics/239287/1
  • From the perspective of bringing the boat upright from the capsized position, the only thing the boat “cares” about is the position of the crew’s center of gravity. Quite simply, the farther you get your weight outboard from the lower hull, the more readily the boat will rotate about the hull and turn upright. Where the righting line is attached to the boat makes zero difference - the only thing that matters is the location of the CG.

    From the perspective of crew comfort while hanging on the righting line, the attachment point makes a difference. The tension on the line equals the crew weight divided by the cosine of the angle that the line deviates from vertical. The greater the angle (i.e. the lower it is attached to the boat), the greater the tension on the line and the greater load you will feel on your arms, hands, and legs.

    sm
  • Quote Where the righting line is attached to the boat makes zero difference - the only thing that matters is the location of the CG.
    Okay, which is better? It seems to me, if it makes no difference, not having to throw the line over the hull is the way to go. What's the consensus?

    --
    Bill Townsend
    G-Cat 5.0
    Sarasota
    --
  • You sliced and diced my post and missed the point.

    From the perspective of the boat rotating ~90 degrees from capsized to upright, it makes no difference where the line is connected. The CG is all that matters.

    From the perspective of the person(s) hanging on the line, it makes a difference. The higher up/farther outboard the line is mounted, the easier it will be on your body.

    Over the hull for sure.

    sm



    Edited by Dogboy on Jun 23, 2021 - 06:33 PM.
  • QuoteOver the hull for sure.
    Thankyou. Intuitively I always knew that was the case. What added to my confusion is the fact that lots of "righting systems" like in Murrays are under under the tramp, not over the hull.

    --
    Bill Townsend
    G-Cat 5.0
    Sarasota
    --
  • Remember, the Hawaiian righting system & variants are always "over the hull". They are attached to the pylons on both sides of the boat, ready to deploy, from above.

    If you have a righting line, have you practiced using it on the water? The 1st time or 3, it's a challenging learning experience, best practiced in calm conditions where you can take time to sort out everything. Capsizing on the water, in choppy conditions & a stout breeze is not a good time to learn where everything is & how to tie/release/reach the line. Things look different from the water, while tightening the straps on your PFD, checking on your crew, & watching your gear bag & cooler sailing away from you faster than you can swim.

    --
    Chuck Miles
    1978 Hobie 16
    1991 Hunter 23.5
    TsaLaGi Yacht Club, Jackson Bay Marina
    Fort Gibson Lake, OK
    --
  • There’s something else to that equation: the righting moment is not affected if the line goes over or under the hull, as long as you are standing on the other hull. That is because the line tension is an internal force of the system boat + yourself. But as soon as your feet leave the boat and your body starts hanging from the line, it does make a difference, because now the line tension is a force external to the boat and with a changing angle. Perhaps at that point it doesn’t matter because you already passed the hardest part, but anyway. If you are pulling the line from another boat, for instance, it also makes a difference.



    Edited by Andinista on Jun 23, 2021 - 10:19 PM.

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