The Double Braid Eye
Since a splice is stronger than any knot, splicing an eye in
double braid line is one of the essential marlinspike arts. Using nylon
line with its greater elasticity, dock lines and anchor rodes can be made.
Polyester double braid is the standard for sailboat running rigging.
Double braid line is made of two braided tubes, an inner core
and an outer cover. When the tubes are stretched along their length, their
diameters shrink, grabbing each other like "Chinese handcuffs".
Whenever possible, use new line to make eye splices.
Used line has probably shrunk enough to make the process difficult, even if it
has never been used. I saw an attempt to splice a thimble onto the
never-used end on a 7/8-inch nylon rode. Apparently, the repeated soaking
and drying caused the line to loose its elasticity so that the eye spice was
impossible. Line that has been under a strain is worse -- the working of
the line causes internal heating from friction which "locks" the strands and
Tools -- Certain items should be available, including:
a sharp knife
a marking pen
Sailmaker's, or other large needle and seizing twin
needle-nosed pliers may be handy
a stiff rod to push the line and fid through the core and
the appropriate-sized fids
Standard fids are the most frequently used. They are
sized for the appropriate line diameter. Wire fids are shaped like a
modified bobby pin, with the ends pointed in to hold the line. They are
typically 1/2 the length of the standard fid. There are also several new
Standard Fid sizes. Modified from "Splicing Guide for STA-SET
X and PCR" New England Ropes, 848 Airport Road, Fall River, MA 02720
||Short Section Measure
||Long Section Measure
Splicing the Eye
|In this version, the links in the text will go to a "still"
of the operation being explained. Use your "back" button to return.
- Begin by placing one layer of masking tape around the line near its
end. Cut the line there to expose a fresh end which hasn't been
melted to seal it.
- Next measure one full fid length from the end of the line and put a
mark on the line there.
- Form the size of the desired loop using this mark as a start and make
a second mark where the loop will join.
- Tie a slip knot, or cleat the line 4-5 feet from the end. This
is needed to prevent too much shift in the core and cover.
- The core is extracted from the cover at this second core mark.
Bend the line sharply and use the needle to tease apart the cover strands
and gradually start working the core out. Needle-nosed pliers may be
useful. STILL. Tape the end of
the core once extracted.
- While holding the core, push the cover down toward the knot or cleat,
exposing more core. STILL.
- Next work the cover back up and mark the core where it exits the
cover. This process re-aligns the cover and core after movement.
- Now push the cover back toward the knot again exposing about 3 fid
lengths of core past the mark. From the mark on the core, measure
one short fid section toward the knot and place a second mark on the core.
Then measure 1 full fid length PLUS 1 short fid section more
and put a third mark on the core. STILL.
- Insert the fid into the core at the 2nd mark aimed in the
direction of the 3rd mark. With new line, you should be able to get
the fid to exit at the third mark without losing the end. If not,
you will need to use the push rod after inserting the cover.
- Insert the cover end into the hollow end of the fid (or attach the
wire fid). Use the push rod to shove the fid and cover out of the
3rd mark on the core. Keep pulling more cover out of the core until
the 1st original mark is exposed. Count eight strands (or sets of 2
or 4 strands) down toward the end and put a 3rd mark on the cover there.
Remove the tape from the cover.
- At this stage, you can optionally taper the cover to produce a better
looking finished eye. Details on tapering.
- Pull the cover back out of the core until the 3rd mark is just exposed
(8 strands past the 1st cover mark). STILL.
- Now, starting at the 2nd mark on the cover (where you originally
extracted the core), measure 1/2 fid length toward the knot or cleat and
put a 4th cover mark here. Next insert the fid into the cover at the
3rd mark (8strands past the 1st cover mark, where it exits the core) and
work it past the second mark to exit at the 4th mark.
STILL. If you are making a large eye,
you may have to exit the cover before the 4th mark, pull up the slack,
re-enter the cover through the exact same hole and continue.
- Insert the end of the core and push it through using the push rod.
Pull out the core until the 1st core mark in seen (where it was originally
extracted from the cover). STILL.
- Next, taper the core from the 1st core mark to the end by cutting and
removing every other strand.
- From the point where the cover enters the core and the core enters the
cover, smooth the line in both directions. The exposed end of the
cover should disappear into the core.
- Now, put some serious tension on the core at this point. You may
want to put the slip-knot around a fixed object so you can pull hard.
What you are doing is stretching the core so that its diameter where the
cover is inside of it is reduced.
- Now, start "milking" the cover back down over the core. You may
want to keep a lot of tension on the core.
- As you continue, beat on the area where the core is going into the
cover to soften the line. Also try putting a stick (hammer handle or
large fid) into the eye and give some sharp, strong tugs.
- Keep going until your very 1st cover mark disappears, or the eye is
snug around the thimble.
- Finish the splice by sewing through the splice part of the eye for at
least 4 diameters, then do it again with the stitch line 90 degrees off
from the first row of stitches;
- Well done.
© Copyright 1998 Bruce
Tetzlaff. Use permitted with credit.
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