Were always amazed how a sailor can spend months agonizing and wringing his hands over which anchor to purchase, and then, when he finally shells out $700 or much more for the anchor, hell attach it to a shackle that has no business being on a boat. Weve plowed through the topic of shackles in several recent issues, but we haven't looked specifically at anchor shackles for more than a decade. Choosing a properly sized, high-quality shackle is important, but its also essential to be familiar with proper use.
All testing was carried out at an approved test facility in Newcastle, Australia: J.L. Robertsons, which is adjacent to one of Australias large coal-mining areas. The test rig is used to certify lifting components for the local mining industry on a daily basis. The facility can test up to 95 tons, far more than we require. This is the same facility where we tested all of our anchor chains. (See PS June 2014, November 2014, January 2015, and March 2015 online.)
If I use 3/8-inch Acco G43 proof-coil chain, why is the same-size galvanized shackle so much weaker? West Marine shows the Acco G43 chain rated at 5,400 pounds maximum working load (MWL), but the similarly sized shackle is rated at only 2,000 pounds MWL. It seems as though whatever size chain I select, the shackle is the weak link. How can I use a larger shackle on smaller chain?
When the forecast turns bad, and its time to find shelter in a new cove or harbor, questions arise about the holding ground, swinging room, and the influence of tide, current, and surge. But there should be little question about the ground tackle and whether or not its up to the challenge at hand. Its true that no anchor comes with a written guarantee to always set and hold, and there are conditions in which each may fail, but the more time one spends anchored out, the more overkill or ground tackle safety margin is warranted. During our acquisition of sea sense, we inevitably discover the range of conditions that our primary (working) anchor can handle, usually discovering its limitations the hard way.
During the initial swap, I couldn't help but notice how much more fluke area the Manson provided compared to the CQR. And the claw-like geometry seemed to more efficiently grab the bottom when compared with the CQRs plow shape. These assumptions were supported during initial anchoring efforts. The Manson grabbed hold of the bottom with very little scope deployed; breakout took a more concerted effort; and the amount of sand, and mud and other detritus retrieved from familiar anchorages was much greater than what the CQR hauled to the surface. The value of a pressure wash-down pump rose considerably.
Rope is the mainstay of sailboat rigging, and knot-craft and splicing are the marks of a seaman. Sewn joins are also practical-and weve explored those in depth (see PS October 2014 online)-but there are times when flat webbing serves better; for example, reefing strops, jacklines and tethers, and straps for attaching sails and tackle to spars. But how do you form the loops required to attach them to hardware and other fittings?
In order to impart corrosion resistance to steel, the items are commonly galvanized, immersed in a bath of molten zinc. Hot-dip galvanizing is well established and accepted, but there are alternate technologies like sherardizing.
As part of our investigation into anchor chain and its attachments (see PS January 2015 and June 2014 online), we examined new galvanizing processes. Steel products that have clearly undergone an unconventional galvanizing process are making their way into the recreational marine market, but because these methods are proprietary, getting specifics about them is difficult. Industry insiders tell us that the galvanizing process is evolving-but few details are made public.
Mention galvanized G70 chain in any discussion, and one of the first comments will be a question of the risks of hydrogen embrittlement. Though hydrogen embrittlement is very real, there have been no well-publicized cases of galvanized G70 anchor chain failure, nor cases of hydrogen embrittlement in new galvanized G70 anchor chain, and negative comment is apocryphal, in our opinion. Scare mongering at its best, or worst.
Practical Sailor carried out its own series of anchor tests in a mud bottom in 2006 (see April 2006 and October 2006 issues), and those tests bore out a commonly known fact: Danforth-style anchors, which feature flukes that are proportionally larger than other types of anchors of the same mass, tend to hold better than older, plough-style anchors in soft mud. When Practical Sailor was invited to witness Fortresss test, editors were initially skeptical; the playing field seemed heavily tilted in Fortresss favor. In the end, however, it was a busy test schedule, not outright skepticism, that prevented our attending.