Saturday, July 18, 2015

More Jacklines

Vertical Jacklines

Who says they all need to be on the deck? I installed a pair of vertical lines to deflect the genoa sheets away from the mast-mounted halyard winches (one on each side), around which they loved to foul during tacks. They are anchored to strong points and the line is 1/4-inch Dyneema, selected because I had it and it was non-stretch. At first I was concerned that the deflectors would be in the way, but I soon realized that they were handy holds and clipping points when working at the mast, much better than clipping to the mast base. I can even lean on the tether in rough weather, allowing for better 2-hand work.


Jacklines and Lifelines as Hand-Holds

It is often said that using the lifelines as handholds is a bad habit. While there is truth to this on a monohull (the leverage on the stanchion bases is cruel when hauling to one side from the deck of a leaner), I disagree for catamarans. The difference is that cats do not heel and that most of the motion is vertical. In heavy going cats pitch, and sailors near the bow can be nearly weightless. Additionally, my jacklines are relatively high at the beam, since they are secured to the hard top. Thus, the safest way to traverse the side decks between the hard top and the tramp is to hold the lifeline in one hand, the jackline in the other, and pull up. Not to the side, not push down, but pull straight up such that your feet are held firmly on the deck. There is little bending stress on the stanchions because the load is vertical, and the support is steady rather than surging roughly as the boat moves. Intuitive to a lifelong climber, something may lubbers and sailors have to be shown.

Pulling up (not to the side!) on lifelines may be a little hard on them, but it is easier on me. Not a mistake, but a well-reasoned standard practice.


Probably just a catamaran thing.

Friday, July 17, 2015

Ducklings always Follow Their Mothers

I guess it is a universal rule.


Cay of Sea and tender, Unnamed cove

The Chesapeake Bay is a small world sometimes. This week we ran into friends we had met over the internet, who dock only a few hundred yards away in Deale, but had never met, face to face. Good stuff.

Tuesday, July 7, 2015

Chafe

Rev. 10-13-2015.

While I am nearly always complimentary of the PDQ and the attention to detail of the designers, everyone makes mistakes. But in this case I can't imagine what they were thinking. It is not just a yard fitting error, since the starboard bow is identical. It's a design error.

For the record, it never did damage either the webbing chafe guard or the line,since the webbing stay stationary relative to the edge, and the rope glides inside. But I still did not like the look of it. A really strong wind could change things. But it does make a strong statement about the benefits of free-floating chafe gear.

With heavy docklines and my normal heavier bridle this little slot between the rub rail and the deck is too small to be accessible and in 6 years has never cause a problem. However, as I started experimenting with lighter bridles for a Practical Sailor article on mooring loads, I found the thinner 8 mm line could slide right into the slot and that the slot is quite sharp, able to slice a line in minutes to hours, depending on the load.



The chafe gear does a fair job of keeping it out of the slot, but I would rather eliminate the slot. My first thought is to fit a block of something into the space, matching the rubber and secured with a screw and 3M 5200. I'd rather not obscure the forward beam bolts.



Rev. 10-13-2015.
While not the prettiest fix--I may trim this to make it purty--this does solve the problem. I cut a rectangle of 3/8" thick mud flap, laminated it to 3/4" thick, and trimmed it to fit the space. I then glued it in with Loctite PL S30. This sealant has virtually the same properties as 3M 5200, with slightly better elasticity. It is also available in white as Loctite PL S40, the only difference being color.

Saturday, July 4, 2015

More Active Anode = More Growth?

I read this in a guidance document by maker of lower potential anode material, and I admit it didn't make obvious sense. Then I started soaking a few trial anode/pipe combinations to help develop a test method for an up-coming anode review.


By December it became clear that unprotected copper fouled less, no doubt the result of more free copper near the surface.

Clearly the more active anode has more growth (aluminum on left, zinc on right, same brand).

Why?