Friday, September 10, 2010

More Climbing Gear for Sailors

rev. 5-30-2011

I've posted information about climbing gear before, as it related to jacklines and safety:

Climbing Gear For Sailors or Jacklines for the Unemployed
Sample Calculations for Jacklines

The funniest comments are those I get about it being "alumiware" and unsuitable for a marine environment. I'm told it won't work or that it will corrode away. While I do give some corrosion and application caveats, I've been sailing saltwater for 25 years, climbing for 30 years, and working as an engineer for 29 years; these aren't theories, suggestions, or ideas that just came to me. These are things I've had in practice for decades and they work exactly as I describe them. Period. Rant complete.

ISO 12401, the governing standard for tethers and harnesses, is published here:
ISO 12401

But there are more uses than that, and much of this gear provides superior value, presumably because of greater sales volume and the more competitive nature of the market. Most climbing gear is rated at 4500-5500 pounds, by international standard (UIAA). This gear is well proven in a tough, safety-critical application.

REI is a good source, as well as many other climbing equipment vendors; perhaps you will find applications I have missed or have taken for granted.

Carabiners. Aluminum wire gate biners hold up very well, weight less (fewer gel coat dings), and are just as strong. Avoid conventional biners; they freeze-up in salt water. MUCH cheaper. Do not use biners as shackle replacements up in the rigging; they can clip onto other lines. Use them only where you would use a stainless carabiner.

Screw gate locking carabiners hold up fine on lanyards IF you are diligent in applying waterproof grease as needed (several times per years is enough) to the screw and the hinge, including the spring inside. If you are negligent, they will lock-up in time.We only use them on the jackline end.

Be aware that conventional (non-locking) carabiners should never be used to clip a safety lanyard (tether) to an eye-bolt, u-bolt, or jackline because of the significant risk of self-unclipping. Read the following from ISO 12401:

5.4 Accidental hook opening testing

5.4.1 The tendency of the hook to accidentally become detached from its attachment point shall be tested
using the following three styles of attachment point, made from 8 mm diameter rod:
a) a straight rod;
b) an eye bolt of internal radius 10 mm;
c) U-bolts of internal radius 15 mm and 20 mm.

5.4.2 Move the hook by hand as far as is possible in the following directions with the attachment point

mounted vertically:
a) move forward and backward, right and left without any rotation, movement being in the horizontal plane;
b) rotate in the horizontal plane by up to 360° using the attachment point as the axis, rotating both clockwise
and anticlockwise;
c) rotate in the vertical plane by up to 360° about the axis of the hook, rotating both clockwise and anticlockwise;
d) rotate in the vertical plane by up to 360° about an axis running through the attachment point, rotating both
clockwise and anticlockwise.

The hook fails the test if it releases from the attachment point. If the hook closure mechanism is shown to
open but not release, this will also constitute a failure, as release would probably occur with geometry of
different dimensions.
No hook will fail a test on an attachment point where its use is clearly and permanently warned against in accordance with 6 g).

Conventional carabiners will always fail this test. Locking carabiners are always preferred on safety and jackline systems. The Kong Tango 715 (on right) is popular on high-end tethers, but cheaper if bought from a climbing gear  distributor. Defender Marine sells them separately also.

Slings. Available in Dynex, Spectra, Dyneema, and nylon, and in lengths from 4 to 24 inches, these are $3.50 to $13 vs. $25 to $65 through marine sources. Just nuts. Good for general rigging, safety rigging while up the mast, prussic hitches on anchor rodes and to relieve tension on lines, and as shackle replacements. Warning: Web-O-Letts (longer versions with an eye sewn in each end) make terrible jackline lanyards; with no stretch at all, it's rather like being caught by steel cable.

Bolt Hangers. Often a good substitute for a pad eye. Available in stainless steel.  $3 to $6. Useful to add blocks to bolts, add tie points, and for harness anchor points. Because these rotate to align with the direction of pull and because the hole is matched in size and shape to average carabiners, they are far less prone to self unlocking or placing off-axis strains on carabiners. Some very large carabiners may not fit. Because they do not mate well with webbing they are generally not good jackline anchor points. Because they are designed for a load in shear, a u-bolt will generally make a better cockpit anchor point. They do make handy lashing points for deck cargo and for adding a turning block to a spot where you already have a single bolt.

Rescue and Hauling Pulleys. Rated at from 2,500 to 6,000 pounds, select ones with all plastic pulleys. A great $25 replacement for a $250 snatch block. This one is by Black Diamond and have kept several on my boat for years. Useful for rigging tackles, barber haulers for the jib, and twings for the spinnaker. Also MOB recovery systems.

Climbing Harnesses. It goes without saying that the sailing companies have copied proven climbing harnesses and doubled the prices. Silly. Big-wall harnesses are the most comfortable up the mast.

Ropes. No, not generally a smart move. Climbing ropes are not fabricated with the same sun-resistance and wear resistance in mind; they are highly engineered for a different purpose. They are generally too stretchy, and even the low-stretch climbing ropes have better marine alternatives. Horses for courses. 

Retired ropes are another matter; they're free, and climbers retire ropes very conservatively. They won't generally feed through a windlass and so make poor anchor lines for larger boats, but they can make excellent anchor lines for smaller boats, where easy handling and knotability are benefits. They have far too much stretch for halyards--don't even try--but they can make fine sheets for smaller boats; yes, this goes against the conventional wisdom and they aren't the best choice, but I've used them for this in a pinch (left the genoa sheet at home after sail repairs) and didn't notice too much difference. I've read of famous cruisers using climbing rope on a main traveler, where a little shock absorption must be a good thing--I went to a spectra traveler when given some free line and know that to be a poor choice, since there is zero stretch. Likewise, if the mainsheet stretches in a puff, this might be good, while in a jib sheet stretch is not desirable, the sail becoming more full at the worst time.

Webbing. Way strong and much cheaper than marine sources for the same material. 1-inch webbing is good for jackline lanyards and chafe gear on smaller lines (<= 1/2-inch) , while 2-inch webbing fits larger lines (see chafe gear page, above). I actually sell these made-up, so this is a free tip for regular readers! Slightly stronger than 1-inch tubular webbing that climbers use is 1-inch flat rescue rigging webbing rated at 6,000 pounds, sufficient to meet ISAF off-shore requirements for much less.

Clothing. Ice climbing gloves are not cheap, but they are dexterous, durable, and warm; frozen but drippy waterfalls have driven some innovative designers. Ski goggles are better than sunglasses, starting when ever your cheeks and nose start getting cold. Fleece socks are great; far warmer than ordinary socks and fast drying. For more discussion on keeping warm, please read my post on winter sailing.

Yeah, I went climbing this weekend. Gravity reminded me how old I'm getting. But I enjoyed swapping stories of the good ol' days with the lads.

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