Lewmar Superlock Still Best Overall Rope Clutch

But if all you want is sheer gripping power, with nary a worry about line abrasion or ability to bleed smoothly, Spinlock’s new XAS holds better than seven others tested.


With rope clutch manufacturers, it’s as though there’s a hired tiercel in constant flight between them dropping messages saying, “Nyaa, nyaa, nyaa, ours are better than yours.”

When introduced in the late 1970s, none of them were very good.

Early rope clutches slipped badly and were tough on rope. These line-holding devices were the successors to the old-fashioned “sheet stopper,” a simple, sharp-toothed cam that clamped down on and secured a line. Sheet stoppers really ate line. Used marine gear stores have stacks of them—usually in two-, three- or four-gang configurations.

The differences between a stopper and a clutch are that the clutch is easier on the line and the line can be trimmed with the clutch handle closed. A third advantage, pursued by most designers, is that a clutch can be “bled” without resorting to a winch to relieve the tension.

Shrewd racing sailors sometimes use two clutches in tandem to fine-tune the easing or prevent the line from running amok…especially the anything-to-save-weight-aloft fanatics who strip the cover from a halyard, leaving a super-slippery core.

As with any good idea, the improvements in clutches started immediately after their introduction. The engineers tried two gripping plates with a compression lever; they slipped. Next came serrated or wavy plates, then rocker actions and cams, with or without teeth. With a cam, the greater the load the tighter the grip…and the more damage to the line.

The Competitors
By the 1980s, Spinlock was at the head of the pack of rope clutch makers. Its “Express” model, a cam with what you might call “soft” teeth, sold like popcorn for a good long time.

But in 1991, Lewmar introduced a stunner — a falling rings design that holds like a bulldog, is gentle on the line and is easy to ease off. The rings don’t clamp down on the line with sharp teeth. They just make the line follow a serpentine pathway whose bends are controlled by the lever. Lewmar had a temporary problem with broken handles on its new “Superlocks,” and our Nick Nicholson (now in Oman) reported in the December 1999 issue a “cosmetic annoyance” because the finish on the handles was peeling off. Competitors still like to point out that Superlocks don’t have much tolerance for different line sizes. Check out the latter on the accompanying chart.

In 1994, Easylock in Denmark and Antal in Italy introduced new models and Garhauer entered the fray. By then, Schaefer had dropped out, along with, as far as Practical Sailor knows, the German Diad and several others.

The testing was more difficult because — instead of good old Dacron, laid or braid — the clutches had to cope with line made of or containing Kevlar (which currently is fading fast in the rope-making business); Spectra (slippery stuff); polypropylene or polyolefin (both of which are light and float), and Technora, which is very strong but not as durable as Vectran, the synthetic that is gaining favor with rope makers. These new lines go by “techy” names like Vizzion, Z-Tech PBO Zylon, Warpspeed, etc. (Almost all of these rope names are registered trademarks. That means one is supposed to use a ™ or ® symbol every time you even breathe the name. In lieu of such copy clutter, consider this parenthetical paragraph as covering any name used herein.)

All through this developmental period, Practical Sailor was testing and reporting periodically on rope clutches.

The development is still going on and, as night follows day, so is Practical Sailor’s testing. Our first major test was in 1987, followed by more bench tests in 1991, 1994 and 1996.

This time it is Spinlock and Garhauer Marine stirring the pot with new models.

Spinlock is a small 30-year-old British company that bills itself as the “world leader in rope-holding technology”. A very proud company, it makes at its plant in Cowes, England, clutches, cleats, stoppers and jammers to handle working loads from as little as 300 pounds to 17,000 pounds. Spinlock products are used on everything from small racing sailboats to production boats to ocean racers to mega-yachts. Their other principal products are tiller extensions and rigid boom vangs.

Alone among rope clutch manufacturers, Spinlock does not believe that bleeding the load on a line is important. Secure holding comes first and foremost with Spinlock. Easing is less important; any deliberate slipping (which is what bleeding is) produces too much line abrasion. The company holds that, as a safety matter, a winch should be used to pick up the load, after which the clutch can be opened to adjust the line. The case for this approach is obvious to anyone who has quick-released a heavily loaded line from a stopper, cleat, clutch or winch. If you don’t have fast hands, you get burned.

Spinlock’s approach is, of course, the antithesis of other clutch manufacturers; they would tend to call a clutch that couldn’t be eased a stopper or jammer.

Spinlock calls its new clutch an XAS Powerclutch, a replacement for its XA model. Instead of a simple toothed cam rolling down along the line, the new clutch has a dual-motion arm that lowers the cam on the line and then clamps down hard. Besides increasing holding power, the new arrangement makes the cam less abrasive.

The XAS is intended for halyards aboard boats up to 28′ and for guys, lifts and furling or car controls on larger boats. It comes in two basic sizes (one for 5/32″ to 5/16″ line and another for 1/4″ to 1/2″ line) in single, double or triple versions. It can be installed upright or, with an available fairing kit, side-mounted on a spar or coaming.

Garhauer, the cost-conscious West Coast company that can no longer be called an “upstart,” has on the verge of introduction a new clutch described as having only two moving parts. It was not ready in time for this test (Practical Sailor held off as long as it could), so a later shoot-out will be needed between the top clutch in this test and whatever Garhauer comes up with. It will be reported as a Practical Sailor Update.

For this test, the existing model Garhauer was used. It is a three-cam clutch whose gripping platform can be fine tuned with an Allen wrench to accommodate different sizes of line,

Going against the new Spinlock(representing the United Kingdom) are the old model Garhauer, a pair of nicely made Antals from Italy; a couple of Francespars from France, and, of course, the long-reigning champion, the Lewmar Superlocks.

(Also originally intended for inclusion in the test, but really not in the thick of it, is an old reliable from Forespar—the Maxi-Clutch—which has been unchanged for years. A big powder-coated aluminum and stainless steel antique, Forespar’s Maxi-Clutch has two tons of holding power and is the only real competition that Spinlock has in the monster clutch range. The Maxi-Clutch handles line from 1/2″ to 3/4″…and you see that size line most on truly big boats.

In the midst of the Practical Sailor tests, Forespar announced that it no longer will make the Maxi-Clutch. If you want one, find it in a catalog and phone your order in to the company as soon as possible.

To facilitate the selection process for this latest round of testing, it was decided to use 3/8″ line. Because modern ropes have such massive safe working loads, the 3/8″ line seemed like a reasonable choice.

Selecting the clutches for any given size of line always poses a problem in that the size chosen might be at the top of a small clutch’s range and the bottom of the next size up. The line ranges for each clutch are shown on the chart.

The usual advice is to use the smallest clutch to handle a given size of line. In other words, if your halyards are 3/8″, use a clutch whose top capacity is 3/8″. To do otherwise (a big clutch on a small line), might mean more slippage.

Partly to test this theory, Practical Sailor elected to test several sizes of clutches.

The Test Procedure
Because modern lines are inclined to be more slippery than good old Samson Parallay—nod if you remember—four kinds of line were used to test the clutches.

The basic choice was New England Ropes’ Sta-Set, a Dacron double-braid that has become a workhorse line at a reasonable price—57¢ for 3/8″.

Selected because it might be difficult to hold in a clutch was Pelican’s Krypton-S, which has an all-Spectra core and a Dacron cover. The 3/8″ size lists for $1.90 the foot.

The third choice was Samson’s new Warpspeed, a hard but light eight-strand HMWPE (high molecular weight polyethylene that Samson calls AmSteel) with a tight Dacron cover. Defender sells the 3/8″ size for $1.60, which is a good buy.

At the extreme end was Yale Cordage’s Yaletail, which truly deserves to be called “exotic.” It has a Dacron/Kevlar cover over a Vectran core. Unless you race for blood you don’t want to know the cost. If you used it to make for your hard-working wife a 30′ backyard out-and-back clothesline, it would cost you about $250.

Because lines made of pure UHMWPE (ultra high molecular weight polyethylene) are so difficult to work with, they were not used to test the clutches. Used primarily on racing boats, line of this kind, which usually is 12-strand single braid or “specialty braid,” goes by trade names like Vectrus, V-12, Spectron 12 Plus, etc.

Back to the workshop…

The clutches were mounted on a board clamped on the workbench.

The test: Insert each line in a rope clutch, tension the line (in “pulls” averaging about 650 pounds), close the clutch, mark the line with a piece of tape, release the line from the winch and measure the slippage. It was originally intended to note also the drop in the line tension. However, this was abandoned when it turned out to be so uniform and so closely related to the slippage.

However, it was important to note how easy, difficult or frightening it is to bleed off the load.

Finally, after each set of multiple “pulls,” we ran a separate additional abrasion test (see photo), to check for line abrasion on each of the four kinds of line.

Because each clutch had to be positioned with the line pull in alignment between the Dillon dynamometer and the winch, it was time-consuming work. Most clutch makers don’t like the angle at which the line enters or leaves the clutch to exceed 10°. That angle, or less, best utilizes the designed strength—and minimizes line wear.

The Bottom Line
All of these modern clutches now hold so well that slippage is not much of a factor. More important, especially to the cruising sailor, is how easy the clutch is to operate and how much line abrasion results.

Without further ado, let it be said with merciful brevity that after manyhours of clamping, cranking, measuring, averaging and record keeping, Lewmar is still the champ, with good holding, the best to bleed and no discernible line abrasion,

However, it must be acknowledged that Spinlock’s new XAS clutch tested out as the best holding. For those for whom the slippage is critical and who want a very positive lock-down, Spinlock is the top clutch—but only if you are willing to use the winch to ease the line and care little about abrasion. Just remember: It cannot be bled. It cannot be released by hand under heavy loads and at even moderate loads it opens with enough force to be a threat to unwary hands.

The Antal clutches (the large one has what the Italian maker calls a V-Groove cam) are very well engineered and manufactured. Their only weak point is line abrasion.

Here are several ancillary basics revealed by the testing:

1. Pulling a line through a clutch with the clutch locked is a plain bad idea. The slippage increases and the abrasion is unacceptable. Perhaps nice for an emergency, but it should not be standard operating procedure. This applies only to Antal, Garhauer and Lewmar. The “closed clutch” data collected in this test are not even included on the chart.

2. For the best holding and smoothest easing, softer lines are preferable. “Softer” does not refer to the finish, but the bulk of the line. In this test, Sta-Set and Pelican’s Krypton are “soft.” Samson’s Warpspeed and Yaletail are hard and stiff, and much more difficult for the clutch to grab, hold and ease. In the manner of things contrary, the hard lines show the least abrasion.

3. Because these tests show that small line used in large clutches results in reduced holding power, it is important to size the clutch to the line used, using the clutches upper limits as the best guide.

4. With any clutch, be very careful when easing a line under heavy tension — 200 pounds or more. Do so gradually; if freed suddenly, the handle can damage a hand and even a flailing tail can be a hazard.

Spinlock’s new clutch holds best. Garhauer’s outstandingly low price makes it the Best Buy. But because it demonstrated good holding and tests the best for abrasion and bleeding, Lewmar still reigns.

Contacts- Antal, Euro Marine Trading, Inc., 62 Halsey St. M, Newport, RI 02840, 401/849-0060, fax 401/849-3230. Forespar, 22322 Gilberto, Rancho Santa Margarita, CA 92688, 949/858-8820, fax 949/858-0505. Francespar, Charleston Spars, 3901 Pine Grove, Charleston, SC 28206, 704/597-1502, fax 704/597-0961. Garhauer, Garhauer Marine, 1082 W. Ninth, Upland, CA 91786, 909/985-9993, fax 909/946-3913. Lewmar, Lewmar Marine, 351 New Whitfield, Guilford, CT 06437, 203/458-6200, fax 203/453-5669. Spinlock, Maritime Supply, 12 Plains Rd., Essex, CT 06426, 860/767-0468, fax 860/767-6560.


Also With This Article
Click here to view “Star On The Chart for Francespar.”
Click here to view Value Guide: Rope Clutches.

Darrell Nicholson, editor of Practical Sailor, grew up boating on Miami’s Biscayne Bay on everything from prams to Morgan ketches. Two years out of Emory University, after a brief stint as a sportswriter, he set out from Miami aboard a 60-year-old wooden William Atkin ketch named Tosca. For 10 years, he and his girlfriend Theresa Gibbons explored the Caribbean, crossed the Pacific, and cruised Southeast Asia aboard Tosca, working along the way as journalists and documenting their adventures for various travel and sailing publications, including Cruising World, Sail, Sailing, Cruising Helmsman, and Sailing World. Upon his return to land life, Darrell became the associate editor, then senior editor at Cruising World magazine, where he worked for five years. Before taking on the editor’s position at Practical Sailor, Darrell was the editor of Offshore magazine, a boating-lifestyle magazine serving the New England area. Darrell has won multiple awards from Boating Writer’s International, including the Monk Farnham award for editorial excellence. He holds a U.S. Coast Guard 100-ton Master license and has worked as a harbor pilot and skippered a variety of commercial charter boats.


Please enter your comment!
Please enter your name here