![]() ![]() We treat the wire under the service to prevent crevice corrosion, and haven’t had any problems there. The stuff is remarkably durable, as the setup on numerous circumnavigating rigs has proven. Seizings and service are made with tarred nylon twine. Anyway, we apply 4 or 5 double Constrictors to the D-rings, onto a short portion of the shroud that has been served. This way you have a higher barrier to falling overboard, and you can work with a very short tether, instead of dragging a long clunky one down the deck. We run jacklines from the stern, up through the rings, then down to the bow. These D-rings live at chest height, usually on the upper shrouds. Recently our star rigger Jen Bates, and her probably-soon-to-be star rigger son, Chance, teamed up to seize D-rings on a client’s boat. Our rigging post Wianno-Lorca, with its post-top hardware suffering the effects of excess tension.Īnother, less dramatic application for heaving mallets is tightening Constrictor Knots, which are basically hose clamps made out of twine (seriously, they are sometimes used for that). I’ll post a picture of them in action soon. We solved this problem by another form of old-school rigging: thumb cleats, onto which we landed Spectra grommets. In the picture below you can see how the metal is just peeling away. That’s fine, but the same increased tensions have wrought havoc on the hardware at the top of the posts. This has happened three times now, but after the last time we put in some serious concrete boulders, and I think things will hold. The added tension has resulted in our heaving right out of the ground the concrete anchors to which our posts are stayed. We still use those posts for their original purpose - the relatively mild tensions needed for full-length service - but a significant portion of what we do now involves Whitehill’s rope, as well as the 12-strand Spectra from New England Rope and Colligo. We tensioned the piece in that picture to somewhat over 1,500lbs on the rigging posts out behind our shop. If you don’t do this, and just splice both ends, you can get a piece of rigging that might grow 6″ or more before it stops elongating. This means pulling on it really, really hard, typically at least 5% of its rated strength, before measuring it and cutting it for its finished length. One tricky thing about using HM fiber rigging is that, while it isn’t elastic once it is set up, its strands need to be “settled” to remove any constructional stretch. ![]() By the way, seizings are also not trustworthy on most “conventional” ropes, like Nylon and Dacron, because these ropes get much thinner when tensioned, so that seizings that start out very tight get very loose, and slip. Seizings just don’t work on uncovered Spectra - too slick - but we have tested it to typical load limits on the Whitehill rope, and the most we got was a minor, expected deformation of the seizing. But this trick will only work if the seizings are really, really good, such that if one leg of the pair is damaged and loses tension, the seizing won’t slip, and also slack the remaining leg. That way you only need to make one terminal at the upper end, instead of two, so you don’t need as many eyes stacked aloft, in traditional configurations, or as many tangs, in modern configurations. The idea of shroud pairs is that you can make two shrouds from a single, continuous piece of wire or rope. Note that I would use a solid thimble for more significant loads than this vessel will impose on this piece. The core of each strand is made of Vectran, so the rope is about as strong as 1×19 wire of the same diameter, but much lighter. That black rope is a high-modulus 3-strand rope from Whitehill. In the picture above, I am finishing a twine seizing on a lower shroud pair. These are basically rolling levers, used to tighten seizings and other knot structures, drawing them tighter than one can do by hand. Most of the time we use turnbuckles for tensioning standing rigging, and block-and-tackle and/or winches for running rigging, but handwork for fabrication often involves tension, and for this we will sometimes revert to more atavistic techniques, like using heaving mallets.
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