Chandlery August 15, 2005 Issue

Wrap Pins

An economical and useful way of protecting sails and skin from cotter pins, while keeping those ingenious devices securely in place.

At the left is an old open-bodied bronze turnbuckle with conventional cotter pins to lock the threads. One pin is taped with self-amalgamating tape. Attesting to the value of good bronze, the turnbuckle was bought used and it appears, except for wear on the stainless clevis pins, to be as good as the day it was made. Second from the left is a modern stainless equivalent, made by Alexander-Roberts, with a Wrap Pin on one stud and a 3/4" cotter ring in the other. Cotter rings are snag free. They're nice on shackles, but are difficult to put in place on turnbuckles (they usually get deformed). Third from the left is a well-engineered Johnson tubular turnbuckle, which has ingenious, locking pins that are captive and very easy to use; the only tool needed is a thumb nail. Note on both ends the cotter rings in the T-toggle shackles. Finally, at the right is a large, 1/2" stainless and bronze turnbuckle, made by Hayn, with a conventional cotter pin, not taped, in one stud and a large Johnson Wrap Pin in the other. At the far right are small (below) and large Wrap Pins.

A cotter pin is a marvelous little piece of half-round soft metal bent into a round-headed, two-legged sliver whose ends can be flared to keep it in place after inserting it in a clevis pin to close the throat of a toggle or a fork.

Cotter pins are simpler than safety pins (they're about equal to a clothes pin, which is an ultra smart bit of engineering design) and just marvelously reliable. Have you ever heard of one failing?

Yes, the little beggars are wont to jump overboard at very bad times, but unless worn out by repeated bending, they do their job. Even if one loses a leg, it soldiers on. Their most devilish characteristic is that when one goes overboard, it somehow makes sure that you have no more.

No one seems to know the origin of the word "cotter." It's said to be from the French, meaning peasant or farm laborer because he occupies a cottage. Known to the British as “split pins,” cotter pins can be called “shackle pins” if you elect to call a clevis pin by its other name—shackle bolt.

And a shackle really is a clevis, whose origin is Scandinavian.

"Shackle" also can mean a 15-fathom piece of chain, also known as a "shot." In England, it's a 12-1/2-fathom length of chain, and that's one eighth of a cable, In the British and German navies, a cable is 1/10th of a nautical mile, or 608 feet (185 meters). The U.S.Navy says a cable is 120 fathoms or 720 feet (219 meters). The French make it something else.

But we digress. Back to cotter pins and shackles, which come in such configurations as D; anchor; bow; Long D, harp; twisted (or reverse key); forelock; heart; flush head; headboard; snap; halyard; oval pin; loose pin; screw pin; captive pin (or keypin), etc.

Except for the fancy ones, shackles require cotter pins.

Another of a cotter pin's dirty little secrets is that they attack ankles and sails and snag lines (especially those with soft-spun covers favored by those not blessed with hands like a sheet metal worker). A particular offender is the marine safety pin, which has a wicked protruding arm that can't really be taped.

Cotter pins often are "booted," along with whatever device they’re mated, like turnbuckles, tangs, various shackles, etc. It's more common to tape them. After weathering, taping becomes difficult to remove….no matter what kind of tape you use. If you trailer a boat, taping is not a good option. (There are other ways, shown in the accompanying photos, to render cotter pins harmless.)

And now there's a new way, from an excellent company started in 1958 by C. Sherman Johnson—and currently operated by his sons, Curt and Burt (that’s the way they sign letters).

Based in East Haddam, CT, the company trademarked the name—"Wrap Pins." Using high-strength glue, cotter pins are perpendicularly attached to a strip of heavy-duty Velcro. To use, insert the cotters (there’s no need to flare the legs) and wrap the Velcro round-and-round. The Wrap Pins are handiest for turnbuckles secured with pins in each of the threaded segments. But they can be used in other ways on shackles; if it's something critical, the cotter still should be flared first.

So far, Wrap Pins come in two sizes, one for 5/16" to 3/8" clevis pins, the other for 7/16" to 1/2" clevis pins. Both sizes, sold in kits of eight, sell for $26.95—a bit more than $3 apiece, which is not bad considering that someone has to cut the Velcro to length, apply a dab of thick glue, work the head of the cotter pin into the glob of glue and then wait for the glue to set well enough to keep the pin perpendicular.

They may not yet be in chandleries, but are in the new 2005 Johnson Marine Hardware catalog.

Contact - Johnson, 800/874-7455,

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