Enclosed Thimbles

[Brian Duff]

Renoir,
I understand your suggestion and see its benefits for minimizing chafe where a thimble wont work. Thanks for speaking up !
I will say that your comment on cleaning up the end link of the chain has a lot of merit. We always polish our thimbles on the bearing surfaces and make sure that all areas are smooth and friendly to the line as they can be.
I can imagine that the polyester line interface will minimize movement, but I often see the friction melting on both nylon and polyester knots after severe loading: such as when I have used various lines and the 'zepplin bend' to lengthen my anchor scope for very high winds or deep anchorages, indicating there is still movement and chafe and damage to lines where they are joined by knots (though obviously because of the relative lengths to stretch, not as much chafe as over a rough large thimble)
I have not done testing on this but still think that a well thought out thimble will provide the most secure, strongest attachment point, if all other considerations in the system allow it.

[Renoir]

You bring out the reality of the continuum in just what damage does occur to nylon under heavy strain. In fact, in the limit, I have seen strands fused together all along the interface (3-strand nylon in this case) between the three strands which become evident only when peeling them apart.

So, I would like to know from your observation where one loop of nylon joined with a loop of dacron under severe strain that has fused some nylon strands if ALSO some strands of the nylon were fused further along the nylon rode itself. Have you looked for that? When I found such an incident I replaced the entire rode, of course.

This condition was caused when anchored bow and stern off Cabo San Lucas years ago (not far from where Bernard Moitessier lost Joshua ashore from not having been anchored really well). I had even dived in the water to check the anchor and watch the boat action in the large swells. The swell would pick the boat up (450 ft of bow line and chain combination with 250 ft of stern line and chain with the stern anchor on 3 ft of water and the bow anchor in 40 ft) and move it back as the rode stretch waaaay out several boat lengths. When the valley of the swell came the boat moved forward back to the original position and everything was smooth but scary.

The boats with all chain would have their bows practically buried in the swell and when the valley came along the boat would fall away from the chain and if the chain was not captured by some bow roller mechanism it would sometimes come crashing down on the toerail damaging various parts of the boat giving a very uncomfortable looking action.

It was after the action died down a few days later and I moved to La Paz that I checked the gear and had to replace the rode. Everything looked O.K. until I began to notice that the eye splice around the thimble would not move at all and it was fused to it. Removing that part I kept pulling the line apart and saw that it was at least slightly fused all along the rode. At least the thimble was stout and did not collapse.