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Conduits & pulling cable 4

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exverizon

Technical User
Oct 11, 2002
105
US
Yesterday, attempting to add a single run of CAT 3 to an underground conduit (4" wide, over 250 ft as it turned out) with a few existing cables--but with lots of room left--the CAT 3 cable I was adding snapped just about 15' before I got it out. The old pull string was OK...it was my cable that broke. No matter, I guess. Broken is broken. I probably didn't lube it very well. My 240' fishtape was too short, so I couldn't go on. (A phone guy friend said he uses shampoo poured down the conduit and it works great...better than Yellow 77). Anyhow, has anyone successfully used one of those "rodders" that are fiberglass fishtapes on a reel, like 400ft long, especially where there's existing cable? My friend warned that, even if I had one, I'd be taking a chance damaging the existing lines. How about equipment that sucks a dart through the conduit? What's worth trying when the conduit is this long and partly occupied?
 
The fiberglass is ok for shorter stuff but even then you have the risk of them breaking. I once fished awall w a fiberglass tape, it got hung on a stud (steel) opening, I ended up breaking the tape. Anytime that I have had a long run like that, I would take 6' of the pull string (if exisitng isn't long enough splice in a section) and tie a series of loops around the cable the whole 6', then tape it up. Having someoneon the other end to ensure the cable does not get hung in the box has always helped as well. I have used the shampoo trick as well, works good when your cable supplier is really out of the way.
 
I used a Shop Vac, string, paper wad, & panty hose on about a 300'ft conduit with existing cable. Worked great.
 
I'd use the shop vac trick and also put several loops on it as suggested,and use shampoo too.

Your first attempt possiably broke because the srting was wrapped around some of the existing cables and binded the one you were attempting to pull in.

I would also pull in more than one cable(just in case and for future useage) or a six pair.

Good Luck,
"It's better to fail trying than to fail to try
 
I hate when that happens! I would also pull a new rope back in. You never know when you might have to pull again! I do this process as a standard thing when I pull conduit runs of any significant length.

You can never have too much lube!

....JIM....
 
Hawks--Describe what you did in more detail: Paper wad--about an inch wide, perhaps? What did you tie to it, light gauge fishing line, like Stren? What role did the panty hose play (afraid to ask)? Was the Shop Vac a large industrial size one (I've got a junior one for home cleanup)?
 
The shop vac trick is going to be your best bet. That will keep your string above all the cables and keep you from breaking another cable.

"Wise men speak because they have something to say; Fools because they have to say something."
(Plato)


 
any trash thats light and will fill the conduit will work . I often use the plastic bags that jacks are shipped in .

you want light line , I use either pull string from the bucket or masons twine .

for a run of that distance I would then use the pull string to first pull some light rope and then the cable and a second pull string for the next guy
 
I see the link didnt work , go to the HD site



Stinger
2-Gallon 1-1/2 hp Wet/Dry Vacuum

Model WD2010
Price: $26.97/ea
 
skip has it correct, the panty hose was just so the paper did not get sucked all the way into the Shop Vac.
Good luck
 
did you tell the cutie at the recption desk you needed to borrow her Pantyhose and you would be glad to help her get them off ? [wink]
 
I was wondering what size they would have to be to fill up a 4" conduit???? You wont find those in the junior misses.

[cheers]

"Wise men speak because they have something to say; Fools because they have to say something."
(Plato)


 
Tried that skip but she said no so I had to go to
Wal-Mart.
 
As far as fiber glass rds go, the longer one are stronger and more rigid. They can come with attachments for the end such as rolers to help makecurves and bounce ver cables. I have used them up to 1000 foot in length and they are fine. Graybar sells a 300 foot one on a reel.
 
all kidding aside the pantyhose idea is good , on more than one occasion Ive pulled a couple of hundred feet of string into the shop vac.

I'm usually working by myself to so it means tying the sting off and going to the other end to check to see if the mouse has made it to the vac and then back.

its one of those DUH! why didnt I think of that things .
 
Skip--I've got that vac at home (never used it on a job), but I can't imagine it would drag much weight (paper plus string) through a 4" pipe very far. Seems the physics would defeat it at long distances: the vac would have to suck a huge volume of air to create enough wind to pull any material with it. Larger conduits like that have a lot of air in them, and the string would have to be thin fishing line (maybe 4# test?) before it would keep going, I'd guess. I've now bought several small styrofoam balls (an inch wide) to glue a line to, and they weigh nearly nothing. But you're saying you've managed to get plastic bags with string attached through pipes this long?
 
We have used regular electrician's pull string, the nylon type sold in the 5-gal bucket at the electric supply. Used a plastic sandwich bag (not a zip top) and put some fiberglass insulation inside of it. Tied the string to the bag, used duct tape to get the vacuum hose on the 4" conduit end, and let 'er rip. Works everytime!!
 
the key is closing off both inlet an outlet as much as possible so when it sucks all it can get is the mouse.
 
I also like using the plastic bag when I don't forget to keep one handy. Because the bag will collapse a little in tighter areas. The paper wad is a last resort because we always have sandwich rappers or something lying around. Make sure that you use a wet/dry vac and not just a normal vacuum.
 
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