Ropes and Stuff
I couldn't help but watch the fellow in the hardware store
trying to make a decision on what rope to buy to anchor his
motorboat with. The young store clerk didn't have much advice
for him; he could only tell him the difference in price between
the different types of rope. Reluctantly, he chose the cheaper
I'm all for saving money. After all, the wind is free and everything
else should be too. Unfortunately, the law of 'you get what
you pay for' prevails. Good rope doesn't cost that much, and
properly selected, works much better than the cheapest alternative.
During the age of sail, ropes were made of natural fibres like
hemp or sisal. The strands of fibre were twisted into a yarn.
Typically, three yarns would be twisted together in the opposite
direction to form a rope. Today, ropes are still constructed
this way, using nylon, dacron or polypropylene. Three-strand
rope is easy to splice into a loop, and has some stretch, which
is useful in some applications. Surprisingly, hemp has very
similar stretch and strength characteristics to dacron. Unfortunately,
it weakens quickly from weathering and rot.
Double braid rope has become the more common choice of rope.
Like the name suggests, it consists of a braided inner core,
and a braided outer 'jacket'. The strength of the rope is divided
between the two braids. This rope can also be spliced, and holds
knots well. It is used almost exclusively on sailboat's rigging
because it runs smoothly through pulleys and works well in the
different types of cleats. Rope that you use for tying up the
boat should have some stretch in it so that shock loads on the
mooring cleats are dampened. Here, nylon is the best choice.
It is strong, has some stretch, is resistant to the weather,
and can even be bought in custom colours to match your boat.
For a little extra money, you can buy them prepackaged with
a loop spliced into one end for looping through a cleat. Either
double braid or three strand rope works well, with the three
strand having a little more stretch.
The most common rope for the rigging on a sailboat is made
of dacron. It is prestretched as it is braided so that it won't
stretch while you're sailing, Double braid dacron is available
in a huge selection of colours and patterns, so that you can
colour code the control lines on your boat. (It's much easier
to ask a new crewmember to pull on the red rope, rather than
saying, 'tension the vang’.) Incidentally, if your spring-loaded
cam cleats no longer seem to be holding the rope under tension,
try some new rope first. This will often solve the problem,
and cost much less than new cleats. Polypropylene is the material
to use if you need the rope to float. The three strand yellow
stuff from the hardware store is made of polypropylene. It is
also ugly and doesn't hold a knot. This stuff comes in different
grades, including a single braid construction that has a soft
feel like nylon or dacron. I use it for some of the rigging
on my own dinghy because it doesn't soak up water in the bottom
of the bilge. If you’ve ever had a wet dacron mainsheet
that wouldn’t feed out the blocks quickly enough in a
gust, you can see the value in using this rope. Polypropylene
is more vulnerable to the sun's UV rays than nylon or dacron.
Try to store this type of rope out of the sun.
Finally, there's rope for high-tension applications where minimum
stretch is required, such as halyards for raising the sails.
Stainless steel wire can be used to replace rope, but it's important
to use the right type of wire. For halyards, where the wire
must go over a pulley, a flexible wire is required. This is
accomplished by using cable made up of fine wires. A common
choice is 7 x 19 cable, which is made up of 7 strands with 19
wires in each strand. The stays and shrouds that hold up the
mast don't have to be flexible, so they are made of 1 x 19 cable,
which is one strand made up of 19 thicker wires. Although it's
not usually seen around here, synthetics such as kevlar, spectra,
and carbon fibre can be used to replace dacron and stainless
steel. These materials are usually used only on racing boats
where minimum stretch and reducing weight are more important
than the higher cost.
Using the right type and size of rope for the job will probably
cost a little more, but you will be repaid with rigging that
works better and lasts longer.