Re: [Paddlewise] The perfect tow line

Bill McKenzie" <wamckenz_at_gte.net> wrote:
>> A manufacturer
is now sending me a sample of what they call their 3/16th "solid braid
multi-filament polypropylene (SBMP)".  Minimum order is 2,000 feet.  I do
not yet know the rated strength of the line.  Remember that my purpose for
the line is towing sea kayaks only and I want it to float.  To keep it a
compact tow system, I am sacrificing its use as a throw bag or, potential
use for such things as unwrapping a stuck boat.  The line is not for
gripping with your hands and I suspect my deck fittings (even with good
backing) may not handle much over 5 or 600 pounds.  (Anyone actually had a
deck fitting get pulled off when towing in large seas or tested the strength
of their fittings?)<<

Back in 1980, when faced with the same problem, I too wanted to find a tow
line that floated and managed to find a source for 3/16 solid braided
polypropylene. (much smoother, knots better and less abrasive than the
thicker strand stuff--like water-ski tow line). I ordered the--then
minimum--1000 feet of it.
I thought it would solve my problem but, reality soon raised its ugly head.
While this line looked and knotted much like nylon solid braid (that we now
use for towlines) it had some major disadvantages for use as towing line. It
didn't have much stretch so, unlike with the nylon, a heavy shock cord would
be a necessity to provide shock absorbsion. Poly was not nearly as strong as
the nylon and it frayed and wore much more quickly as well. Friction would
melt it easier too. The crowning disappointment was that while the line
itself floated even several thicknesses of it would not also be enough to
float even the small nylon jib snap that I wanted to have on the business
end of the towline for one-handed convenience. This meant that I would still
not be able to retrieve the short (floating) bow line from the cockpit with
out still putting a small float near the jib snap to keep it on the surface.
(no problem with the longer stern line that hooks in front of the cockpit--I
simply back up and pluck it out of the water beside me. Well, if I was going
to have to do put a float on it anyhow what advantages were there? None, the
nylon's superior strength, wear characteristics and stretchiness (no bungee
needed for shock absorbsion on a 3/16 line only 12 to 15 feet long) was a
much better towline. It took me years to use up the rest of that 1000' poly
roll for tying bundles and odd jobs. Save your money.
The smooth nylon solid braid in 3/16" is what you want. Just run it through
a little foam float near the business end. Smooth 3/16 nylon solid braid
won't cut your hand like the more abrasive weaves (like those often used for
rudder lift lines) might. Any heavier like 1/4 or 5/16 and you loose some of
the shock absorbing characteristics and will probably have to futz with
shock cord loops (which may make it more likely to tangle and create much
more bulk to store). Thinner nylon is plenty strong for towing (but would be
more likely to cut your hands). However, the major disadvantage of thinner
lines is that they are also much more difficult to untangle and get
unknotted.
We use polyester (Dacron) solid braid that looks almost the same as nylon
for deck gear lines because it doesn't stretch near as much as nylon when it
gets wet. Be sure that you use nylon and not Dacron for a towline though
because it is stronger and the shock absorbsion is built in.

Once in about 4 foot breakers I started to try to tow a kayak that had sunk
at one end using a 3/8" nylon solid braid whitewater style throwline that I
had just cleated to a 5" cleat on my back deck. After the first breaker
surfed me off to the end of my rope, stopping me cold, I quickly uncleated
the line and held it in my hand against the paddle shaft so I could release
it immediately if a breaker surfed me forward too fast. I had to circle back
out and pick up the throwline several times before finally getting that
kayak out of the breakers (but the cleat never got ripped out of the back
deck of my kayak, so I didn't get to test just how good the backing plate
would hold up and what part of the system would fail first).

Matt Broze
http://www.marinerkayaks.com


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