Cable-Tying with Waxed Twine

Thu Jan 25 15:21:34 UTC 2007

On Wed, Jan 24, 2007 at 09:41:22PM -0700, Larry Beaulieu wrote:
> > The other thing I found interesting; The use of Zip Ties on Copper Cabling 
> > is frowned upon by BICSI.  Velcro preferred.
> > 
> > Something to do with the compression on a twisted-pair cable caused by 
> > over-tight nylon cable ties screwing with their twist rates, and thus 
> > changing their Crosttalk characteristics...
> 
> Yep.
> 
> For starters, the stuff that Dan Mahoney is looking for is properly known as
> waxed linen lacing cord.  In a past life I used to order the stuff made
> by Ludlow Textiles through Graybar, their part # back then was 89039323. It's
> not always in stock in individual stores.
> 
> 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
> 2) can harden and/or become brittle over time, eventually failing under stress
> 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.


	This (and the other superbowl related emails) reminds me of
a time I had a DS3 go down (on superbowl sunday).  It had some
chronic errors that would pop up where it would go down  seemingly
randomly.  What we found out after a few more outages was that this (LD)
carrier who placed their facilities next to train tracks had a
more chronic issue of a train going by and causing LOS or errors on the
circuit where they handed it off on coax to the ILEC/CLEC.

	Getting someone dispatched to look at the circuit on that
sunday was problematic to say the least ;)

	- jared

-- 
Jared Mauch  | pgp key available via finger from jared at puck.nether.net
clue++;      | http://puck.nether.net/~jared/  My statements are only mine.