Thursday, September 2, 2010

32 lashes

Steve on s/v Siempre Sabado discusses his ratlines, and why he switched them from clamped to lashed fastenings...

Today, I finished redoing the ratlines on the starboard side. Not sure if I wrote about it earlier but the ratlines have been bothering me. You may remember that the way I attached them to the shrouds was basically to clamp them in place using a nut and bolt on each side of the shroud. Worked great but it left these 2" pieces of wood sticking out on each side beyond the shroud. This meant there were 32 possible places for lines to hang up on or sails to chafe against. I kind of knew this but was in a bit of denial until Steve Webster at Riverbend Boatyard in Newport said it out loud. I knew I had to change the setup.

I pulled out my trusty "The Rigger's Locker" by Brion Toss and studied how he said to do it. I didn't follow his suggestion to use 2 rope ratlines for every 1 wooden one since I prefer all wood rungs and since they were basically all built already. I took down all the ratlines and took them with me when I headed back to Cody's house earlier this month.

What I had to do was to a.) glue both faces of each rung to its mate, b.) cut off the end of each rung bisecting the hole that went around the shroud so that I'd end up with a groove instead of a hole, and then c.) drill a hole parallel to the groove but 1-1/2" to 2" in from the end to take the lashings. Having use of my chop saw and Shopsmith made this project way easier than it would have been on the boat using hand tools.

Yesterday evening I mounted the first 2 rungs and today I completed the rest of the ones on the starboard side. The following photo shows how the rungs are lashed to the shrouds:

I hate those little knotted ends sticking out. Two of them will be eliminated along with the double constrictor knot they're attached to but there will always be one. Brion says to finish of the wraps with a couple of overhand knots, pulled very tight and then back that up with a figure eight to use as a stopper. He says to work the figure eight up tight against the overhand knot but, try as I might, I could never get it to snug up and stay put. The double constrictor knot was just something I added. I was having some trouble with the rungs wanting to slip a little when I really put force on them when tightening wraps on a higher rung while standing on a lower one. I was essentially pulling up with my arms while pushing down (on the rung) with my feet. It was almost inevitable that there'd be some slippage. So, I added a double constrictor knot around the shroud just below the wraps as a sort of collar to keep the rung from slipping down. It didn't work - the constrictor knot slipped as well. Tomorrow I'm going to get some good old fashioned friction tape and wrap the shroud where I'm going to make the lashing. Hopefully that will help. If this was galvanized rigging, I'd serve the entire length which would really help, and help the rigging last a long time, too. But stainless steel needs oxygen so service would be a bad idea.

I prefer this photo since it doesn't show the little knots:

The bolt is there just to reinforce the face-to-face glue joint and to keep the lashing from splitting the wood. In Brion's example he uses solid (not glued) wood but still uses a copper rivet to prevent splitting.

The ratlines are plenty tight and tough enough to support a person doing normal things aloft like navigating through coral heads or trying to spot a whale. But, as noted above, they are likely to slip when excess force is exerted on them. Consequently, it would be great if I could have installed them from the top down. But I didn't see any workable way to do that. As a result, I ended up redoing probably half of the lashings before I was all done. In this photo you can see that I still have one left to straighten up:

In case you can't tell, it's the aft end of the second one from the bottom. Needs to come up about 1/2".

But, just so you know that these "lash-ups" really can carry the load:

Until later, ta-ta from Charleston.

Check out the comments on the original post for more information.

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