Sails, Rigging & Deck Gear

When researching Changing Views on Chain Hooks (see PS, March 2016 online), we were surprised to discover that some chain hooks greatly reduced the breaking strength of a chain. Unless the hook itself broke, we assumed its effect on chain strength would be very minor.

Swageless wire-rope terminals have long been a favorite piece of rigging kit among all kinds of sailors. These terminals are inspectable, reusable, and can be assembled with simple hand tools. But for all of their acknowledged advantages, data is scarce about their mechanical efficiency. How much, if any, do they weaken the wire rope they are attached to?

During the first round of mechanical terminal testing, testers were surprised to see that wire failures were occurring at loads that were at least 10-percent lower than expected. The swaged-end fittings had been applied by a rotary swage machine, which is considered to be a very reliable way to form swaged terminals.

The most common error with poured sockets is insufficient cleaning of the wire, and/or using the wrong solvent to clean it. Even dry, stainless wire, when new, can have a residue of lubricant left over from the extrusion process. If this lubricant is not removed, it can compromise the adhesion of the wire yarns to the filler material in the socket.

Mechanical terminals more expensive than the usual alternative-swages-but they also have many advantages that swages do not.

All of the mechanical terminals we tested are based on the same assembly concept: The rigger opens the cover yarns, and then slides a wedge over the core yarns, near the end of the wire. The rigger closes the cover yarns over the wedge, and then, screws together the two outer parts of the terminal over the wedge, compressing the material, and thus generating friction. Simple, but like any assembly, it can be done wrong. Here are a few things to watch out for when assembling a mechanical terminal.

In our recent article on anchor swivels (see PS September 2015 online), we reiterated our view that swivels are unnecessary in most anchoring situations. For those who insist on using one, we suggested staying away from cheap varieties, and using only load-tested designs that exceed the rating of the anchor chain from every angle of pull. (None of the ones we have found that meet this criteria are cheap.) Shortly after that article, Mantus Anchors, a relatively new maker of anchors and anchoring accessories, introduced its swivel, which it claims is as strong as an ordinary shackle and priced in a range that ordinary cruisers can stomach.

We know the theory behind using anchor swivels: The swivel releases any twists in the chain when an anchored boat swings through 360 degrees or more. Still, we question the logic of using them. Our skepticism is supported by our own experience, previous testing, and input from long-term cruisers, but we wanted to devise a test to investigate chain twisting.

There are a number of ways to attach a snubber to an anchor chain. A gripping hitch, a soft-shackle, or a chain hook are the most common. Of the three, Practical Sailor has a strong preference for a camel hitch or similar gripping knot, but for the many who seek a faster, simpler way to attach a snubber, here is a look at chain hooks.

When it comes to snubber sizes and diameters, catamarans present special challenges, and usually require a bridle, with separate lines leading from the hook to each hull. Heres an example of the bridle-type snubber that PS contributor Jonathan Neeves uses on his seven-ton, 38-foot catamaran that he lives aboard and cruises in Australia.