[Paddlewise] Impact loading of tow rope

I've tried many different lines for towing. 3/8" is way bigger than
necessary and even in nylon, not stretchy enough. The loads will be much
higher on you and the towee unless you also add a big bungee cord into the
system making it even more bulky to carry and more awkward to use. I find
that while you could use 80 to 100 lb. fishing line thinner lines tangle too
easily and are more difficult to untangle. The best compromise I have found
is using about 3/16 inch diameter of the stretchiest least tangling nylon
(nylon is stretchier than polyester, polypro, or kernmantel--with or without
Kevlar cores). I like solid braided nylon (rather than cored nylon for this)
as it knots very well too. Even a ten to fifteen foot towline of 3/16" solid
braid nylon has enough stretch so that you don't have to be gentle about
hitting the end of the towline. The tower can just paddle off and hardly
notice the jerk (even without a shock cord loop to tangle up the line). Make
sure you cut this line about 20% longer than you think you will need. You
will loose 10% or more to shrinking the first time it gets wet and it is a
lot easier to shorten a line than lengthen it. Nylon braid gets even
stretchier when it is wet. Climbers favor kernmantel type ropes because they
stretch less than braided or twisted nylon ropes. Too much stretch might
mean that a climber would crack her skull on a rock that a less stretchy
rope would have stopped her short of hitting. The stretchiness and strength
of nylon make it the tow rope of choice. If only it floated like poly it
would be ideal. I suggest you add a float to any end you will need somebody
to be able to pick up off the water. When I tried floating solid braid in
3/16" after a long search to find it I was disappointed that the little
nylon hook on one end sunk anyhow (and the poly wasn't as strong, as
stretchy, and abraded and melted (due to friction) much easier. I had that
1000 foot roll around for years before I was finally able to use it all up
in non critical uses (never on a kayak). Nylon solid braid in 1/4" or 5/16"
works very well for tying kayaks to vehicles and lasts a long time (stored
out of the everyday sun) but is too heavy for towing a kayak. 3/8" is
probably overkill even for tie down use.
Matt Broze
http://www.marinerkayaks.com

original message:
<SNIP>
<While Mike's calculation of 60-ish pounds was a worst-case scenario, for
<a sudden stop, I should probably go for the 3/8" stuff.  Especially
<considering what Dave pointed out: the deterioration factor!

<Shawn

- --
<Shawn W. Baker          0                                    46°53'N
<© 2000            ____©/______                              114°06'W
<~^~^~^~^~^~^~^~^~^\  ,/      /~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^
<baker_at_montana.com    0        http://www.missoulaconcrete.com/shawn/



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