Cleat Strength
I am upgrading the anchoring system on my Morgan 382. So far, Ive installed a 5/16″ chain rode with a 45# CQR. By paying close attention to load limits and ultimate strengths, Ive been able to purchase component parts with similar ratings, including shackles, swivel and some nylon at the end of the chain should I ever need to cut the rode free in a hurry.
Ive upgraded the bow rollers, beefed up the windlass installation and have finally reached the end of the project, literally, the cleats. The original cleats are two-bolt horn cleats mounted on top of the bulwarks. Two 5/16″ bolts don’t seem beefy enough, so Im looking for four-bolt bronze cleats to mount securely on the deck, to better distribute the heavy loads.
The problem is that I can’t find any strength data on cleats. It would be unfortunate if, after having carefully matched all the components for strength, I ended up with cleats not strong enough. One of the best methods for determining what equipment is strong enough is to look at commercial boats. They don’t mess around! However, in this case, their massive bitts and welded-on cleats don’t help me much. Can you?
Jim McEntyre
Kona, Hawaii
As with anchors, there are at any given moment sailors in every time zone whittling patterns for new cleat designs. But when tug comes to yank, the cleat sailors depend on is the good old horned version.
It can be a fat finger of teak, ironwood or lignum vitae mounted in two cast bronze rings with mounting feet; these are favored in Europe and they are handsome.
It can be open-based (with lots of room to tie fenders and a pull-rope), a slimmed down mid-section, tapered ends and very thick legs accommodating in each foot a pair of flathead machine screws. Sometimes called a Herreshoff cleat (West Marine calls them yacht cleats), they come in stainless or bronze.
A cleat also can be a two-bolt closed or open base casting of chrome-plated zinc or Zamak. Theres also a teardrop-shaped thing that looks like a hood ornament on a car. Theres even one of these plated cleats that looks like the Herreshoff cleat, and it costs more than stainless ones.
As for strength, a stainless Herreshoff cleat (especially powerful are Wichards forged versions, in either stainless or bronze) contains a lot of metal, especially in the legs. The tensile strength of the cross-sectional metal could be calculated, but it would exceed that of the fasteners. So, it becomes the strength of the fasteners that is the issue.
And thats why the four-bolt versions shine.
A good quality #10 stainless machine screw has a breaking strength in excess of 6,000 lbs. A #12 goes about 7,750 lbs.
So, an 8″ Herreshoff cleat, stainless or bronze, with four feet containing four #12s, with a good backing plate and generous washers, yields a breaking strength of about 30,000 pounds!
As a practical matter, the size of cleat to buy is determined mostly by the amount of line you intend to belay on it. A 4″ cleat with four #8 fasteners may well be strong enough, but a 10″ cleat will take a lot more turns-and there are times when it will be expected to handle two, three or even more lines.
Because you mentioned cleats plural in your question and want bronze, wed suggest a couple of Wichard 6″ #1362BRs, each with four #10 bronze or stainless fasteners treated with an anti-seize compound. In the West Marine catalog, they go for $13.99 each. Bronze fasteners and washers? If you can’t find them on the islands, you can get them from Jamestown Distributors, 28 Narragansett, Jamestown, RI 02835, 800/423-0030, fax 800/423-0542.
