and Techniques > Basic crimping techniques
or swaging as it sometimes called is a quick and reliable method
for making joins in monofilament and cable. However some of
the techniques are misunderstood and fish are often lost due
to poorly made crimped connections. After youve read this
youll be building leaders that are the envy of your fishing
Remember, practice makes perfect. Learn these methods at home
when the weathers too bad for fishing and never lose another
fish to a bad connection.
are three main types of crimp sleeve in common use.
2. Oval section
3. Double barrel
The less said about these the better. They are usually made
from brass and are compressed with a point to cup type crimp
tool. They dont make a strong join but are just about
adequate for some light tackle applications. If youre
desperate and cant tie a knot use these.
This style is in almost universal use on commercial longline
vessels, and they catch some pretty big fish using them. They
are available in various brass and copper alloys and in aluminium
and you will need a cup to cup type crimp tool to compress them.
These are an excellent choice for serious anglers. When appropriately
sized for the leader in use and compressed with the correct
tool they create a very strong and reliable connection. Bear
in mind though that in saltwater two dissimilar metals can set
up a corrosive reaction and if aluminium sleeves are used to
join steel cable they will corrode away in a remarkably short
period of time, just like the sacrificial anodes used on sea
For this reason aluminium sleeves should only be used for joining
monofilament, whilst brass or copper sleeves can be used for
joining either monofilament or cable.
Double barrel sleeves are my favourite. They make a strong neat
join and there is no danger of the cable or monofilament crossing
over itself inside the sleeve.
are also in common use on longline boats, but due to being very
slightly more costly than oval sleeves they are less popular.
Longliners use an awful lot of sleeves so every cent saved is
important, but thats not really such an issue for charter
captains or private anglers who use far fewer.
oval sleeves, double barrel sleeves are available in both brass
or copper and in aluminium. They should also only be compressed
with a cup to cup style crimping tool.
same comments regarding corrosion apply as for oval sleeves.
Its important so Ill say it again. Use aluminium
sleeves for monofilament only, use brass or copper sleeves for
either monofilament or steel cable.
barrel sleeves are available in both standard and heavy-duty
models. The standard sleeves are only available in brass or
copper, whilst the heavy-duty sleeves are available in brass,
copper and aluminium. These heavy-duty sleeves are for use with
heavier leaders and larger crimping tools and are often generically
referred to as Nicopress sleeves.
Crimping tool styles
are four major types of crimping tool that you are likely to
hand Point to Cup, right hand cup to cup
Point to cup
2. Cup to cup standard duty
3. Cup to cup heavy duty
4. Cup to cup bench press
These tools can be purchased relatively cheaply from tackle
shops around the world. They resemble a large pair of pliers
with semi circular cut outs on one jaw and a series of pointed
teeth on the opposite jaw which match up with the opposing cups.
They are used with round section crimp sleeves and they roughly
flatten the sleeve around the leader without forming fully around
make a very inadequate connection and are not suited to rigging
for big fish. I guess you can tell that I dont much like
Ill discuss these together because the principle is the
same for all of them.
they resemble a large pair of pliers, but the opposing jaws
have matching pairs of semi circular cut outs (the cups). There
are usually three or four different sized cut outs depending
on the brand of tool.The
jaws usually have markings to indicate the appropriate sized
sleeves to use with each cut out. Each cut out will usually
accommodate several different sized sleeves either oval section
or double barrel.
These usually accommodate standard sleeves up to around 2.0
mm 2.2 mm diameter, good enough for 300 400 lb
monofilament or 600 lb cable. For most anglers this should be
all youll ever need.
These are a more costly version of the standard tool, built
to much heavier standards and capable of handling standard and
heavy duty sleeves as large as any angler is ever likely to
need. These are usually found on charter boats, in tackle shops
and in the workshops of serious heavy tackle anglers.
These use pretty much the same jaws as the heavy duty tools
but have an extended handle and are bench mounted to facilitate
crimping large quantities of heavy sleeves. They are not portable
and are reasonably expensive so are usually only used by tackle
companies, some larger tackle shops and commercial longline
a basic crimped connection in monofilament
your monofilament leader and select a suitable sleeve. This
can be alloy or copper, oval or double barrel, whatever you
like, but it should fit snugly over the mono whilst still sliding
the mono through the sleeve, make a loop and pass it back through
the sleeve in the opposite direction. Pull an extra 2 or 3 inches
through the sleeve.
a cigarette lighter and melt the tag end of the mono. When it
softens and starts to turn into a ball press the melted end
against the lighter or other hard surface to spread and flatten
the leader back through the sleeve and the flattened mono end
will sit snugly against the end of the sleeve without pulling
back through. Now you can adjust the size of the loop.
your crimp tool and select the appropriate cut out to suit your
sleeve. Position the sleeve between the jaws of the tool so
that the concave faces of the cups bear against the curved edges
of the sleeve. Do not crimp all the way to the ends of the sleeve
as this will cause the edge of the sleeve to cut into the monofilament.
Make sure that you have left about 1/16 inch (1.6 mm) between
the end of the sleeve and the tool.
correct note the uncompressed centre section
and the flared ends of sleeve. Right incorrect
the sleeve has been compressed in the wrong direction
damaging the monofilament
the tool tightly closed and the sleeve should compress around
the monofilament. If using a small sleeve you will only need
to crimp it once, but larger sleeves may require that you move
the tool along and crimp it once or twice more along its length.
If possible leave a 1/16 inch (1.6 mm) space between each compressed
portion of the sleeve, and the same at each end. The sleeve
should have a flared appearance at each end.
using this technique to attach hooks, swivels or any kind of
anti chafe tube or loop protector youll need to remember
to thread the leader through them before passing it back through
the sleeve and crimping it closed.
a basic crimped connection in cable
a crimped connection in cable is pretty much the same as with
monofilament, but there are a couple of important differences.
Use brass or copper sleeves only. It doesnt matter whether
theyre oval or double barrel.
2. Ensure that you dont leave an exposed tag end of wire,
this can cut you badly when you are leadering a fish. You may
need to use a second sleeve crimped over the tag end to achieve
this, just pass a couple of extra inches of leader through the
first sleeve before crimping it tight. Then either wrap the
tag end around the main leader before crimping them with the
second sleeve, or if youre feeling clever you can haywire
twist the two lengths of cable before crimping.
Crimping all the way to the end of the sleeve
This causes the edge of the sleeve to cut into the monofilament,
always leave about 1/16 inch (1.6 mm ) uncrimped at each end
of the sleeve.
Using alloy sleeves on stainless steel cable
As previously mentioned this causes rapid corrosion of the alloy
sleeve quickly weakening the joint.
Using the wrong size sleeve
Its pretty much impossible to use too small a sleeve,
the leader just wont fit inside it. However it is possible
to use too large a sleeve.
purpose of crimping is to deform the metal of the sleeve around
the leader and not to simply crush the crimp until it touches
the leader in as many places as possible. Choose a sleeve that
is a comfortable snug fit on your chosen leader material.
the wrong tool will cause the joint to fail under pressure
Not using the correct crimping tool for the sleeves in use or
not using a crimping tool at all
all met the guy who isnt prepared to waste his hard earned
Dollars on the right tool for the job. He says that he can do
just as good a job with pliers, a bench vice, a hammer, his
hands, his teeth or whatever.
they cant, thats the beginning and the end of it.
will be damaged by all these methods and whilst cable is more
forgiving the individual strands can also be damaged. These
methods will produce a joint that sometimes holds up to average
fish but will fail when pushed to the limit.
you consider that a standard crimp tool costs less than 1/20
of the price of a standard trolling charter and should last
at least 10 years it seems a false economy to use anything else.
never seen a correctly crimped connection fail. Fish can be
lost for all sorts of reasons but this neednt be one of
Using the correct tool incorrectly
people think that a cup to cup crimping tool should be used
with the metal ridges between the semi circular cups pressing
into the central groove between the two barrels of a double
barrel sleeve or into the flat surfaces of oval sleeves.
is wrong, the pressure is exerted by the curved surfaces of
the cups against the curved sides of the sleeve.
Leaving a tag end protruding from the sleeve
isnt a big problem with monofilament although it does
look untidy and catches on weed and debris in the water.
you cant avoid a tag end use a crimp protector to cover
is a different story though. A tag end of wire can cut you badly
when you are leadering a fish. Always ensure that the tag ends
are covered by a sleeve.
Not crimping the sleeve
Unbelievable but true, its very easy to be distracted
and forget to actually crimp the sleeve! Ive done it,
but hopefully having read this you wont!
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