How to Fish Wires Through a Conduit or Pipe

PDF download Download Article
PDF download Download Article

Suppose you have an existing pipe or conduit for electrical wires, speaker wires, phone or internet cables. Trying to push something through the pipe will undoubtedly just leave you frustrated. Pulling is the only answer. But, how do you pull another wire through that pipe?

Steps

PDF download Download Article
  1. [1]
  2. Try to seal the connection the best you can to make the most efficient use of the vacuum. The vacuum should pull the string through the pipe. [2] .
    • Watch the end where the string is feeding into the pipe to make sure it doesn't get snagged and stop. It is important to be aware of how much string has been pulled in, so you know when to expect the string's exit on the other end.
    • Watch the end where the vacuum is for the appearance of the string. If you don't, a lot of string can be sucked into the bowels of the vacuum cleaner.
    Advertisement
  3. Once you have pulled the light string through the pipe, attach a heavier string / rope to the end, and pull this through manually.
  4. Once the heavier string / rope has been pulled through the pipe, attach your final wire or cable, and pull this through manually. If needing to pull more than one to three smaller wires, connect wires in such a way that the point of connection to the heavy string is not a single "clump of wires" folded over. This will make for a difficult "pull" through the conduit. Instead, connect only one wire directly to the string, create one or more loops in this wire 6 - 8 or more inches down the wire from the connection point. Slip any additional wire(s) several inches into the loop, fold over and wrap around the first wire. Repeat this as often as required and wrap electrical tape around the string / rope just above the connection point all the way down just beyond the last wrap of the last wire hooked through the loops. The result should look like the end of a pencil and will pass much easier through the conduit. [3]
  5. If the conduit run is long, has several bends, has more than 25% of its area filled with wires, etc., the strength and flexibility offered by a fish tape or snake will make pushing into the conduit much easier. Often times it can be used to pull new wires directly into the pipe - saving time of multiple pulls of increasing strength string / rope. Fiberglass does not conduct electricity and is highly recommended for use instead of metal fish tapes and snakes. [4]
    6. Advertisement

Community Q&A

Search
Add New Question
  • Question
    Why am I having problems getting fish tape to go through a 4-inch conduit with two 1/2 inch diameter cables already in the conduit?
    Community Answer
    The existing cables are not likely to be laying neat and flat in the bottom on the conduit - rather they have several twists around each other over every few feet. This makes getting a snake through the pipe difficult. You can damage the insulation of the cable if you force it through - and if you are able to get it out the other end of the pipe, you have to pull it and the wire you connect to the snake slowly so as not to wear down the cable insulation from friction of dragging new cables over the existing cables.
    Thanks! We're glad this was helpful.
    Thank you for your feedback.
    If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
    Yes No
    Not Helpful 10 Helpful 8
  • Question
    What do I do if my pull string breaks?
    Community Answer
    Try again, there isn't much you can do. Just pull the cable out and the string out the other end.
    Thanks! We're glad this was helpful.
    Thank you for your feedback.
    If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
    Yes No
    Not Helpful 3 Helpful 0
Ask a Question
200 characters left
Include your email address to get a message when this question is answered.
Submit
      Advertisement

      Video

      Tips

      • A spinning reel is a great source of easy feed "string". [5]
        Thanks
        Helpful 0 Not Helpful 0
      • Tie a cotton ball to the end of the string to help pull it through.
        Thanks
        Helpful 33 Not Helpful 10
      • If you are pulling heavier cables or electrical wires that bind as they are pulled through the bends and fittings of the pipe, you will need to apply a suitable lubricant (often called "soap" by electricians) to the wire as it enters the pipe. Be aware that many household lubricants can do serious and permanent damage to some types of wires and cables (most common wires and cables are PVC insulated), so consult a professional and acquire the proper type of lubricant. Many "big box" home supply centers sell wire pulling lubricant in the electrical department. In a pinch, many diluted household detergents and liquid soaps may be used with success.
        Thanks
        Helpful 2 Not Helpful 1
      Show More Tips
      Submit a Tip
      All tip submissions are carefully reviewed before being published
      Name
      Please provide your name and last initial
      Submit
      Thanks for submitting a tip for review!
      Advertisement

      Things You'll Need

      • Household vacuum cleaner or shop vac
      • Light string
      • Heavier string, or light wire that will be strong enough to pull your final wire or cable

      You Might Also Like

      How to
      Remove a "Knock Out" from an Electrical Box
      How to
      Replace a Defective Electrical Switch or Outlet
      How to
      Calculate Total Resistance in Circuits
      How to
      Install Cabling in a Pre Built Home
      Identifying Positive & Negative Wires: Colors & Power Types
      How to
      Test a Fuse With a Multimeter
      How to
      Solder Wires Together
      How to
      Strip Wire with or without a Wire Stripper
      How Do 15A and 20A Outlets Differ? What You Should Know
      How to
      Test an Outlet with a Multimeter
      How to
      Run Electrical Wires through Finished Walls
      How to
      Install a Circuit Breaker
      How to
      Find the Fuse Box or Circuit Breaker Box
      How to
      Determine Amperage of Circuit Breaker
      Advertisement

      References

      1. ↑ https://www.youtube.com/watch?v=c6y5gyldRDE
      2. ↑ https://www.youtube.com/watch?v=c6y5gyldRDE
      3. ↑ https://diy.stackexchange.com/questions/163799/tv-cables-getting-stuck-in-conduit-after-mounting-tv-on-fireplace
      4. ↑ https://www.electricalknowledge.com/electricians-tools/what-is-fish-tape/
      5. ↑ https://www.youtube.com/watch?v=3Wk4TsBJEgk

      About This Article

      In other languages
      Thanks to all authors for creating a page that has been read 344,373 times.

      Did this article help you?

      Advertisement