Couple of afterthoughts (after reading all the other posts):
1. I believe the rule of thumb is that the conduit should be at least twice
the diameter of the cable bundle.
2. A lot of people have reported that it's easier to run the cable when the
conduit is laid, just slipping it over the cable as you go along. I tried
that once with a feed to my telescope pedestal and it was a real mess. The
work had to be done at the bottom of the ditch, and a lot of dirt got on the
cable and in the conduit. Made gluing the conduit together a real hassle.
Again, YMMV.
73, Dick WC1M
> -----Original Message-----
> From: Dick Green WC1M [mailto:wc1m73@gmail.com]
> Sent: Tuesday, February 26, 2013 2:32 AM
> To: 'Dick Dievendorff'; towertalk@contesting.com
> Subject: Re: [TowerTalk] Wire lubricant for cable pull thru conduit
>
> Hi Dick,
>
> I would second all of Jim's answers. A few extra points:
>
> 1. You can get a 3" foam mouse at your local electrical supply store
> (the one local contractors use). Home Depot might have them, too. Tie
> some strong but light nylon cord to it, and pull it through with a good
> high-horsepower shop-vac sealed to one end of the conduit.
> Alternatively, you can make your own mouse out of foam rubber and maybe
> some cardboard and a small eye bolt.
> You should put the spool of cord on a dowel or something similar so it
> can spin free while feeding the cord. You can slide the dowel between
> the legs of a small step stool or ladder to support it. Once the mouse
> makes it to the other end, remove the mouse, tie your pull rope to the
> cord, and pull the cord back through. Of course, the spool of rope needs
> to be supported so it can spin and feed the rope freely. This is how the
> pull rope was installed in my three conduits -- 4", 2.5" and 1" -- which
> are 265' long with 90-degree sweeps at both ends and a 90-degree turn
> about 2/3 of the way to the tower. No problem at all. I was amazed by
> how fast that mouse made it from one end to the other!
>
> 2. I've used a couple of different varieties of synthetic rope as pull
> rope.
> What I like best is the plastic-like stuff that doesn't stretch much. I
> think it's the rope rated for marine applications. You don't want the
> cloth-like stuff that stretches a lot. If you use that for the rope you
> leave in the conduit for future pulls, it'll absorb water and might rot
> (see my last point below.)
>
> 3. The need for lubricant varies. Initially, my 4" conduit only had two
> runs of 1/2" coax. No lube needed to pull those, even with the long
> length and the 90-degree bend. The 2 1/2" conduit was more packed. As I
> recall, there are five or six 8-conductor cables in it, ranging in size
> from heavy-duty rotor cable to small Cat5-like cable for switching. No
> problem pulling that bundle with no lube, either. The 1" conduit has
> three runs of #10 THHN electrical wire for a crankup tower (no longer my
> main tower), and again no lube was used to pull them. About a year ago,
> I removed the two 1/2" coax runs and replaced them with two runs of 1/2"
> heliax (Andrew LDF4-50). I bought something like 6 or 7 quarts of pull
> lube at home depot. I opened one of the quarts at the house end and
> positioned myself at the tower end. A friend fed the two cables at the
> house end (the cable was unrolled completely and laid out in the yard
> because it wasn't on a spool. If your sweeps are in place, you
> definitely need someone to feed the cable bundle because it has to be
> lifted overhead and fed down into the conduit. Well, I started hauling
> on the pull rope. There was a fair amount of resistance at first, but
> then it started moving (I ran the rope through a pulley attached to the
> utility box panel so I could pull horizontally instead of standing on a
> ladder and pulling the rope straight up.) I kept pulling and pulling,
> expecting that at some point my friend would call me on the HT to tell
> me to stop pulling so he could open another bottle of lube. But pretty
> soon the head of the heliax bundle appeared at my end of the conduit. I
> went back to the other end and asked my friend how much lube he needed.
> He said I pulled the cable through so quickly that he never got a chance
> to apply any lube at all! I ended up returning all but that one open
> bottle of lube for a refund at Home Depot. YMMV, of course. I would be
> prepared with enough lube to do the job, but don't open all the
> containers. Home Depot carries several different kinds, and I believe
> some are explicitly rated not to dry out or harden. Check the label.
>
> 4. The subject of water in the conduit comes up a lot on TowerTalk. The
> general consensus is that water is going to get into your conduit no
> matter what you do. I thought that didn't apply to me because my conduit
> was professionally installed and there's never been any sign of water at
> either end in over 15 years. Well, when I pulled that 1/2" coax out a
> section of it was wet. The wet section was about 1/3 of the way to the
> house, right where the conduit makes the 90-degree turn. That must be
> where the leak is. 2/3 of the conduit runs down a steep hill to that
> bend, and then the conduits slopes up gently to the tower the final
> third of the way. So I think the water just pools at the bend and
> hopefully, leaks back out into the surrounding soil. Some people drill
> weep holes in the conduit to let the water drain, and I believe some
> have actually used irrigation tubing instead of conduit. You can search
> the TT archives for all the talk about that you'd ever want to see.
>
> Hope this helps.
>
> 73, Dick WC1M
>
> > -----Original Message-----
> > From: Dick Dievendorff [mailto:dieven@comcast.net]
> > Sent: Monday, February 25, 2013 3:08 PM
> > To: towertalk@contesting.com
> > Subject: [TowerTalk] Wire lubricant for cable pull thru conduit
> >
> > I?ve never run anything through conduit before.
> >
> >
> >
> > 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.
> >
> >
> > 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.
> >
> >
> >
> > What?s the right sort of lubricant for this? What quantity should I
> > buy?
> >
> >
> >
> > 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. After I have that
> > pulled through, I assume I attach it to a hefty pull cord. What sort
> > of pull cord should I be shopping for?
> >
> >
> >
> > Any tips on tying the ?bundle? to the cord so that I have a smooth
> > thing to pull? I have Kellums Grips suitable for ½? coax, but not for
> > anything else.
> > Is this a ?pulling eye??
> >
> >
> >
> > 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.
> >
> >
> >
> > Should I tape the whole bundle together every few feet?
> >
> >
> >
> > Thanks,
> >
> >
> >
> > Dick, K6KR
> >
> >
> >
>
>
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