Sunday, June 5, 2016

Mooring Between Pilings

With the approach of hurricane season, I look forward to another season of watching people add lines without a plan. They double lines to cleats that are too small,  underestimate slack requirements, and put lines the wrong places. I've got a long article on dock lines and forces coming out next month in Practical Sailor. I

got a lot of funny looks, sitting on the dock edge during gales and squalls, taking reading on on line tension on both my boat and others using a block and tackle and load cell. Just two thoughts here:

Instead of adding a spider's web of lines that take loads in unpredictable ways, try a simple pattern of full spring lines. If you squint, notice how they form 4 over lapping Vs, with redundancy in every direction. Additionally, no cleat has 2 lines on it. (the double green/orange lines refer to data in the article--they are single lines.) This is how I tie my boat every day, and it really minimizes motion. Because the springs are actually continuous from piling to piling, they only take seconds.

Which brings us to the mind-ships cleat hitch. Because it is only one line but must be secure in both dirrection it is just a little different. Basically a standard cleat hitch, with a crossing turn after the locking hitch to reverse the rotation, and one more round turn. Very easy and clean.

The end result is that I can break any combination of 2 lines and still stay in my slip. The other result is that I don't wear lines, because they are always sharing.Easy and robust.

I have another article on  bulkheads in progress. More load cell testing. The interesting take-away from that one is that I use polyester spring lines (on bulkheads only--nylon between pilings) to reduce fender movement.

For storms I would add a few more, but that is another story.

No comments:

Post a Comment