# Pull string installation in conduit



## UncleMike (Jan 2, 2013)

I'm going back to a site next week where I'm expecting to pull 2 Cat5e and 2 coax cables through 250 feet of 2" rigid conduit that has 4 90-degree bends in it. I know the length and number of elbows because almost the entire length of conduit is on the roof of the building, with short stubs coming through the roof at the demarc and tenant space.

All I had with me the other day to get string through that conduit was a Milwaukee M18 vacuum; I didn't even try it. I have a 6HP Ridgid vac that I can bring with me next week, but I'm not sure how well that will work either, considering the number of couplings along the conduit and that the couplings aren't going to be air tight. I'm considering bringing my cordless leaf blower and blowing the line through (after making a relatively sealed connection between the blower and the conduit.

Is there some alternative way of doing this that I should be prepared for when I get there?

FYI - I wasn't originally prepared for this because the demarc extension I'm going back to install was supposed to have already been installed by another contractor (who has since been fired).


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## HackWork (Oct 2, 2009)

Bring bags to make parachutes. I know they make "mice" to use with the vacuums, but plastic bags always worked much better. The only question is how much bag you need for that size pipe. Rigid couplings should be sealed enough for this.

As a last resort, bring 2 150'+ metal snakes, if you have them.


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## hardworkingstiff (Jan 22, 2007)

I agree with HackWork that the bags work better.

I have had difficult times getting jet line (poly pull line) in long runs and found if I used a nylon string it went easier. 

I've also found I get better results blowing over vacuuming.


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## trentonmakes (Mar 21, 2017)

Seal off pipe around the vacum best you can and should be no problem.
3xs on the bag!
Just tie off on a strip of the bag in the middle so it kinda resembles a bowtie.
Any good shopvac should suck it up.



Texting and Driving


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## varmit (Apr 19, 2009)

Sometimes, you can use two vacuums- blowing at one end of the conduit, and the other sucking at the other end. ( Yes, sounds kinky.)


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## splatz (May 23, 2015)

You may be pleasantly surprised how fast it zips through 250' of rigid if it's unbostructed and in good shape. If it doesn't, it might take just a little fiddling and creativity. 

Four 90s can be hard on communications cables - I'd lube the hell out of it from both ends.


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## Cow (Jan 16, 2008)

If the fittings are made up wrench tight, like they should be, you should have no problem with a shop vac and a small plastic grocery bag. This is assuming the conduit is free of moisture.


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## macmikeman (Jan 23, 2007)

It's going to take about 1-2 seconds from the time you turn the vacuum switch on to the time you hear the string drawn into the receiving end .


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## Signal1 (Feb 10, 2016)

^^^Agree with every poster here^^^

Shopping bag like a parachute work better than mice
Poly line (in the bucket)
Compressed air works very well if its available
It zips through very fast

A few years ago I did this with a DPW crew with a trailer mount compressor (for a jackhammer), on a 400' underground. As we were setting up they thought I was nuts with a silly grocery bag.
Within 2 seconds after opening the valve the guy on the other end looked like he got attacked by Spider-man.


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## tjb (Feb 12, 2014)

Had a tough time once with emt and set screw couplings letting too much air through. Ended up grabbing a block of duct seal and globbing the tops of the couplings. Duc tape might also work in a pinch. But I agree, you should have no problem.


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## Grogan14 (Jul 16, 2009)

The M18 vac and bag hasn't failed me yet. Did 600' the other day, like nothing.


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## UncleMike (Jan 2, 2013)

Thanks for the quick replies everybody!

I've only ever used bags (never had any mice), and had good luck on buried PVC (once we blew the water out of it), but bad luck with EMT (probably screw couplings). My main concern is that 2" conduit would need more air flow than my vacuums could provide.

I'm going to have to blow the line through, since the one end of the conduit that's accessible stubs out through the roof about 20 feet up. The other end does the same, but it's above a hard ceiling with the nearest access at last 10-15 feet away. My plan is to blow the line through from the accessible end, and then hook the string/bag from the access panel at the other end. Then I'll have to pull the cable from that end back to the accessible end.

I'll let you know how it goes. 🤞

Sent from my SM-T713 using Tapatalk


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## Ty Wrapp (Aug 24, 2011)

I just sucked a bag and jet line thru 2 4" ridged conduits 600' each. Used a 5hp vac, no problems. Used the jet line to pull in mule tape, the mule tape pulled in the armored fiber and another mule tape.


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## John Valdes (May 17, 2007)

Ty Wrapp said:


> I just sucked a bag and jet line thru 2 4" ridged conduits 600' each. Used a 5hp vac, no problems. Used the jet line to pull in mule tape, the mule tape pulled in the armored fiber and another mule tape.


Hey buddy! Where ya been?


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## Ty Wrapp (Aug 24, 2011)

I came out of retirement...now I spend my days pulling data cable. 

I don't have as much free time as I used too.


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## Flex277 (Jun 2, 2014)

UncleMike said:


> I'm going back to a site next week where I'm expecting to pull 2 Cat5e and 2 coax cables through 250 feet of 2" rigid conduit that has 4 90-degree bends in it. I know the length and number of elbows because almost the entire length of conduit is on the roof of the building, with short stubs coming through the roof at the demarc and tenant space.
> 
> 
> 
> ...




Alotta times on runs like that, if pheasable I'll rent a pull behind compressor and shoot 120 psi continuously, usually about 70 bucks but it gets it done fast


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## John Valdes (May 17, 2007)

Ty Wrapp said:


> I came out of retirement...now I spend my days pulling data cable.
> 
> I don't have as much free time as I used too.


I see that. Did retirement not live up to the expectations?


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## UncleMike (Jan 2, 2013)

Much to my surprise, once I setup a ladder so I could reach the accessible end of the conduit, I could see there was a string already in it - secured with tape to the outside of the conduit. After tying my bucket of string to it, I was able to hook the other end of the string inside the conduit from about 10 feet away, and pull the new string to the access panel in the ceiling.

After loading up the conduit with Klein foam lube and pulling a bag through to lube the inside of the conduit, the cable pulled through relatively easily while applying more lube to the cable itself as it went through the access panel.

Plenty of lube was used, but no blowing or sucking required!

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