You are looking at a chafe section on the high modulus dock lines we have been using aboard Wind Horse. After 45,000+ miles of cruising, much of it in rough surroundings when docked, this original inventory is still going strong.

The outer cover is polyester and their primarily as a first line of defense against chafe (it contributes little to overall strength.

We’ve discussed the advantages of high modulus dock lines before, but to recap:

• They are stronger
• Lighter
• Stretch less
• And are easier to coil and throw.

These photos are of 3/8″ (9.6mm) Yale Cordage Vectran. Our other polyester only dock lines are 7/8″ (22mm), almost four times the weight!

When we started using these lighter dock lines we assumed they would be switched out to the heavier set once we were secured. However, in practice the heavy set are only used when we are stored in the water.

The lack of stretch is an advantage as long as the hardware on the dock and boat are up to the shock loads in a surgey marina. The boat part is easy, the dock part can be more difficult. Although we have yet to pull a dock cleat off its mounting, we are always wary of the risk. Sometimes in rough marinas we will switch out the high modulus lines for stretchier material.

A word on knots. Although bowlines weaken the break strength of high mod cordage, they are convenient, and we have used them without problem. You do have to leave the knot loose, as shown above. Otherwise it is likely to tighten itself and be extremely difficult to undo.

The FPB 64s come with both dual braid polyester and high modulus sets of dock lines.