Cable-Tying with Waxed Twine

Thu Jan 25 06:16:07 UTC 2007

Confession time - I'm over 50

At 09:41 p.m. 24/01/2007 -0700, you wrote:

>As for plastic ties (TyRap is the brand name for the Thomas & Betts version)
>they may be easy to use, but they do have several functional drawbacks,
>including:
>
>1) difficulty in maintaining consistent tension from tie to tie, and as
>    a correlary it is comparatively easy to overtighten one, risking
>    compression-related damage to the underlying cabling, or as mentioned 
> above,
>    increasing crosstalk when using twisted-pair cables

You can buy a cable-tie gun from Panduit, along with ties on a bandolier. 
They are used in appliance manufacture for making up wiring looms, instead 
of lacing them.  The tension is programmable .You may also remember that in 
cars, the wiring harness was in a cloth jacket......

>2) can harden and/or become brittle over time, eventually failing under stress

H'mm - you buy various grades of cable-tie. I have a lot of personal 
experience with a black Ty-Rap. Its black with a stainless-steel tag. The 
black makes it UV-stable and I get nervous if we don't have a few thousand 
in stock. I carry a few hundred in my van... White ties aren't UV stable 
and so are indoor rated only.

Of course I live in a country where the weather report gives a UV rating 
each day, due to the Ozone depletion making a hole right above us - due to 
CFCs in aerosol can's. Thanks guys....and girls.

Get Joe Abley to tell you about CityLink over a few beers. But basically, 
its a 20Km metro fiber network suspended off the trolley bus wires. I built 
the fist 200 odd buildings, before we got "staff". The fiber is attached to 
a synthetic rope (kevlar) which is the catenary wire, by a TyRap ty25 (from 
memory), every 300 mm. The way we work was my van pulled the trailer with 
the fiber drum, Ryan and Glenn were in the cherry-picker, moving from pole 
to pole. I was on the ground cable tying like mad. Ryan then pulled the 
cable up, tensioned it, made it fast,and we moved on. Been doing it since 1996.

These days we use self supporting fiber, so run much faster, no cable ties 
until we overlay....

>3) typical background vibration causes them to tend to chafe the sheaths 
>of the
>    wiring that the ties are in direct contact with, over a period of years.

buy the ones with stainless tags - they last for years. The cheap plastic 
ones are toys

>Lacing is a lot slower than using platic ties, and doing it is rough on your
>fingers.  If you're lucky you know a data tech who can show you how to do it
>properly, it's really not something that you can just describe in writing.
>
>Depending upon the specific need, contact points may also have pieces of fish
>paper laced to them before the wiring is laid out and laced into place.
>Not unusual to see this when DC power cables are being secured.

H'mmm - the DC cables I'm used to are the size of your arm - per 
polarity.....we don't lace them, just bury them. But sorry - I'm old and 
been around. I worked in a power utility for 14 years. BTW Broadband over 
Power - we call ripple control. It turns on the street lights, load control 
etc. Been doing it for years and its not hard to go both ways. Zellweger in 
Uster Switzerland used to make the cool stuff. I have photos somewhere.....

We also inject DC into the AC network, but thats another beer or two. First 
you have to work out why the utilities use AC......

Rich