dock line construction/measurements
I have a question about how dock lines are made and measured. When I look at the dock lines on my boat (they came with the boat), they are 0.71" as measured with calipers. They have 2 strands each of 2 colors arranged side by side (the same color next to itself) in what appears to be a braid pattern -- this is double braid, right? I noticed my jib sheets look exactly the same, except they use 3 strands -- would this be 3 strand line? Both types of line I have appear to have an outer sheath over some kind of inner core. I can't see the construction of the core because the ends are fused to prevent unravelling. Now here's the really big question... since 0.71" is about exactly between 5/8" and 3/4", which do you think is the original size of the line? If we measure dock line thickness by just the core and not the sheath, I'd believe they're 5/8", but if the sheath is measured too, then probably it is 3/4" that has gotten thinner due to stretching/age. I'm trying to figure out what size to buy for some more dock lines, and since both of those sizes seem sufficient for my boat (37', 19500lbs), I'd like to get ones that match the existing ones. I'm looking at double braid from west marine because they have a deal going on. Thanks.
1979 Gulfstar 37 Laissez Faire