[TowerTalk] Wire lubricant for cable pull thru conduit

[Jim Brown]

On 2/25/2013 12:07 PM, Dick Dievendorff wrote:
> I’ve never run anything through conduit before.

I'm far from being an expert on pulling cable, but I've done a bit of 
it, both as a sound system installer and in the home I owned in Chicago.

> I have a 100 foot long 3” conduit between house and tower, and in that
> conduit I hope to run two ½” coax cables, three 3-wire ROMEX cables carrying
> 24V for three different rotators, two 8-conductor (CAT-5 like) cables for an
> antenna switch, and three two-wire cables for the rotator position
> indicators.  It’s a good-sized bundle.  There are no 110 AC power lines in
> the bundle.

That's good, because power in the same conduit with low voltage wiring 
is a code violation. To reduce conduit fill, you might want to consider 
is using another single 8-conductor for position sensing with a break 
out at both ends (rather than the three paired cables). For most 
rotators, a bit of loop resistance is not significant in the sensing 
circuit. Also, I'd try to find smaller stuff to run the rotator motors. 
I'm using #14 Romex for my 24V rotator motors too, but it's laying on 
the ground and the run is considerably longer than yours.

> I think I need to pull all this at once, with lubricant, and include a
> length of pulling rope or tape in the bundle for “next time”.   I believe
> that I want to pull these through all at once  in order to avoid risk of
> damage to cables already installed.

Yes on all counts. Although the primary reason for pulling them all at 
once is that it's easier to do it that way. If your conduit is not 
over-filled, it should be possible to add more cable later.

> What’s the right sort of lubricant for this?   What quantity should I buy?

I'll let someone else respond to this. There are dedicated pulling 
lubricants, but some can turn into glue later on.

> I have some light nylon “fish” cord that I think I can pull through with a
> small wadded up plastic bag and a shop-vac.

There are dedicated tools to shoot light weight pull line through 
conduit. It's also common to push a steel "fish tape" through the 
conduit and use that to pull the cable.

> After I have that pulled
> through, I assume I attach it to a hefty pull cord.
Right

> What sort of pull cord should I be shopping for?

Smooth and strong.

> Any tips on tying the “bundle” to the cord so that I have a smooth thing to
> pull?

The two most important things are that the pull rope doesn't come loose 
from the bundle, and that the "head" of the bundle be as smooth as 
possible. For large bundles, it is common to strip insulation from the 
conductors, twist them together, combine them smoothly with the pull 
rope (or pull wire or fish tape) and put a robust wrap of tape around 
the whole thing.

> I have Kellums Grips suitable for ½” coax, but not for anything else.
> Is this a “pulling eye”?

I've never heard of this being done, and to the extent that it adds 
rigidity to the bundle, it could be a bad thing.

> I presume I want one person on each end that can communicate, one to feed a
> smoothed bundle in one end while the other pulls.

Yes. And as it gets closer to the end, the feeding person may also be 
pushing. :)

> Should I tape the whole bundle together every few feet?

I've never seen this done. The bundle should be taped together ONLY 
where it is connected to the pulling line. That will allow it to fit 
better around bends, and it also makes it possible to remove a cable (or 
use one cable to pull through a new cable).

73, Jim K9YC