Pulling cable

I need to add a length of coax to an existing feed.
I have done this a few times before, but I just wondered... is there a
'best/preferred' way of connecting a pull-cord to the cable?

Neil

On 28/12/2011 10:57, Neil Bush wrote:
I need to add a length of coax to an existing feed.
I have done this a few times before, but I just wondered... is there a
'best/preferred' way of connecting a pull-cord to the cable?

I don't know preferred, and depends on what space you are pulling
through, but I get away with using 2-inch shiney brown polypropylene box
packing tape, wrapping first the thinner diameter cable/cord and then
overwrapping the other placed side by side. I used to use knots but
found them more likely to get stuck in a void somewhere.

--
Adrian C

"Adrian C" wrote in message ...

On 28/12/2011 10:57, Neil Bush wrote:
I need to add a length of coax to an existing feed.
I have done this a few times before, but I just wondered... is there a
'best/preferred' way of connecting a pull-cord to the cable?

I don't know preferred, and depends on what space you are pulling through,
but I get away with using 2-inch shiney brown polypropylene box packing
tape, wrapping first the thinner diameter cable/cord and then overwrapping
the other placed side by side. I used to use knots but found them more
likely to get stuck in a void somewhere.

Ah, thanks for that, I see what you mean. I haven't ventured up there yet,
but I do expect it to be a snug fit, as there is already cable using that
route.

"Neil Bush" wrote in message ...

I need to add a length of coax to an existing feed.
I have done this a few times before, but I just wondered... is there a
'best/preferred' way of connecting a pull-cord to the cable?

Neil

I use 6mm diam polypropylene rope, and thread the wire in and out of the
rope strands a few times, making off the lead and tail with gaffer tape.
This way the more you pull, the tighter the wire is gripped.

AWEM

On Wed, 28 Dec 2011 10:57:50 -0000, Neil Bush wrote:

I need to add a length of coax to an existing feed.
I have done this a few times before, but I just wondered... is there a
'best/preferred' way of connecting a pull-cord to the cable?

I just lay the two side by side and tape over. Forming some sort of
ramp over the bit that sticks out on the forward direction.

The big boys (telephone/power etc) pull cables through ducts with a
large "finger trap" threaded several feet onto the end of the cable.

http://www.wikihow.com/Create-a-Chinese-Finger-Trap

Think you'd need something fairly "dead" rather than "springy" to
make one. A length of coax braided screen would work but probably not
very many times as copper isn't very strong.

--
Cheers
Dave.

Neil Bush wrote:
I need to add a length of coax to an existing feed.
I have done this a few times before, but I just wondered... is there a
'best/preferred' way of connecting a pull-cord to the cable?

Neil

I usually use another piece of coax. The thing is to make sure that the
joint is a smaller diameter than the cables, and that it has no edges or
protuberances that might snag.

So: Carefully strip back about three inches of outer sheath. Preserve
the braid by either unravelling it or pushing it back over the sheath.
Cut the dielectric off without nicking the inner. Pull the braid back
over the inner. Do this for both cables, the puller and the pulled. Tie
a reef knot in the two lengths of braid/inner, but make sure the knot is
fairly close to the remaining plastic on both cables, otherwise the
joint is too flexible near the knot and can snag on a corner. Wrap the
joint with pvc tape, overlapping the plastic just once, pulling the tape
tight, adding rigidity but being careful not to exceed the cable
diameter. Make sure the tape bridges any protuberances.

Make sure someone feeds the cable as you pull, because otherwise it's
more likely to snag.

If it snags pull it back a yard then twist the pulling end one turn and
try again.

That's how I do it.

Bill

Yes, me too, though I also cut the leading end of the cable being
pulled through at a slant to enhance the ramp effect when it's all
taped up. I use standard electrical tape.

On Wed, 28 Dec 2011 12:21:33 +0000 (GMT), "Dave Liquorice"
wrote:

I just lay the two side by side and tape over. Forming some sort of
ramp over the bit that sticks out on the forward direction.
--
================================================== =======
Please always reply to ng as the email in this post's
header does not exist. Or use a contact address at:
http://www.macfh.co.uk/JavaJive/JavaJive.html
http://www.macfh.co.uk/Macfarlane/Macfarlane.html

On 28/12/2011 12:21, Dave Liquorice wrote:
On Wed, 28 Dec 2011 10:57:50 -0000, Neil Bush wrote:

I need to add a length of coax to an existing feed.
I have done this a few times before, but I just wondered... is there a
'best/preferred' way of connecting a pull-cord to the cable?

I just lay the two side by side and tape over. Forming some sort of
ramp over the bit that sticks out on the forward direction.

The big boys (telephone/power etc) pull cables through ducts with a
large "finger trap" threaded several feet onto the end of the cable.

http://www.wikihow.com/Create-a-Chinese-Finger-Trap

Think you'd need something fairly "dead" rather than "springy" to
make one. A length of coax braided screen would work but probably not
very many times as copper isn't very strong.

You can get commercial versions of those to go on the end of cable rods
and fish tapes:

http://www.tlc-direct.co.uk/Products/FXSK1115.html


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 28/12/2011 12:45, Bill Wright wrote:
Neil Bush wrote:
I need to add a length of coax to an existing feed.
I have done this a few times before, but I just wondered... is there a
'best/preferred' way of connecting a pull-cord to the cable?

Neil

I usually use another piece of coax. The thing is to make sure that the
joint is a smaller diameter than the cables, and that it has no edges or
protuberances that might snag.

So: Carefully strip back about three inches of outer sheath. Preserve
the braid by either unravelling it or pushing it back over the sheath.
Cut the dielectric off without nicking the inner. Pull the braid back
over the inner. Do this for both cables, the puller and the pulled. Tie
a reef knot in the two lengths of braid/inner, but make sure the knot is
fairly close to the remaining plastic on both cables, otherwise the
joint is too flexible near the knot and can snag on a corner. Wrap the
joint with pvc tape, overlapping the plastic just once, pulling the tape
tight, adding rigidity but being careful not to exceed the cable
diameter. Make sure the tape bridges any protuberances.

Make sure someone feeds the cable as you pull, because otherwise it's
more likely to snag.

If it snags pull it back a yard then twist the pulling end one turn and
try again.

That's how I do it.

Nice description... do you mind if I pilfer that and slap it on the end
of the cable pulling section in our wiki. Seems like it would fit nicely
he

http://wiki.diyfaq.org.uk/index.php?...lling_Ca bles



--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

Neil Bush wrote:

Ah, thanks for that, I see what you mean. I haven't ventured up there
yet, but I do expect it to be a snug fit, as there is already cable using
that route.

If it's a really tight fit, it's sometimes easier to pull out the
existing cable and pull in two new ones, rather than dragging the new
cable past the old one. Mind you, this is mainly relevant to ducted
cables. It's a trick I learned when I worked in BT.

--
SteveT