Pulling wire through conduit is one of those jobs that looks simple from the outside and then humbles you the first time you try it on a long run with a few bends in it. The wire jams, the insulation scrapes, or the whole pull just stops moving halfway through. Knowing what to do before you start saves a lot of frustration and a lot of damaged cable.

This guide walks through the tools you need, the steps to follow, and the common mistakes that cause damage during a pull.

Tools You Need Before You Start

A few items make every pull go more smoothly.

Fish tape

Fish tape is a flat, flexible steel or fiberglass strip wound on a reel. It pushes through conduit and pulls your wire back through. Steel fish tape works for shorter runs and straighter conduit. Fiberglass works better in longer runs or where there are multiple bends because it doesn't bind as easily.

Wire pulling lubricant

Pulling lubricant is a slick gel or liquid designed for use on cable insulation. It cuts friction inside the conduit so the wire slides instead of dragging. Don't use grease, dish soap, or other substitutes. Real pulling lube is cheap and it makes a huge difference, especially on longer runs.

Pulling head or grip

A pulling head or basket grip attaches your fish tape or pull rope to the wire being pulled. A basket grip squeezes tighter as you pull, which keeps the wire from slipping out. For multiple conductors, a head with multiple slots lets you pull them all at the same time.

Pull rope

For longer runs or heavier cable, a pull rope is sturdier than fish tape. You can use a vacuum or compressed air to blow a small line through the conduit first, then use that to pull a heavier rope through, then use the rope to pull the cable.

Cable rollers

For pulls that involve cable runs along the ground or through pull boxes, cable rollers keep the cable elevated and reduce friction. A good roller setup can cut pulling force by a lot and protect the cable jacket from scrapes on rough surfaces. For overhead telecom and fiber optic work, slap on rollers and slide stop rollers attach to lashing wire and keep the cable moving smoothly through the run.

Step by Step Through the Pull

The basic process is the same for most jobs, with some variation depending on length and how many bends are in the run.

Plan the run

Look at the route from end to end. Count the bends. Each 90 degree bend roughly doubles the friction in the pull. If you have more than 360 degrees of total bends between pull points, the pull is going to be hard. Add pull boxes if you can to break up the run.

Get the fish tape through

Feed the fish tape into the conduit from the easier end. Push it through until it comes out the other side. If it gets stuck, pull it back a few inches and try again with a different angle.

For runs where the fish tape won't push through on its own, you can blow a string through with a vacuum or compressed air, then attach a heavier pull line to that string and pull it through.

Attach the wire

Strip a few inches off the end of the wire and form a small loop. Hook the fish tape through the loop and wrap it with electrical tape so it doesn't snag. For multiple wires or heavier cable, use a pulling head or basket grip.

Apply pulling lubricant to the wire as you feed it into the conduit. A good rule is to coat the first ten feet heavily and then keep adding lube every twenty feet or so as you pull.

Pull from the other end

Have one person feed the wire into the conduit while another person pulls from the far end. Steady, even pressure works better than yanking on the line. If the pull stops, don't pull on it harder. Back off, add more lube at the feed end, and try again.

For long runs, set up cable rollers along the floor to cut friction and keep the wire off rough surfaces.

Avoiding Damage During the Pull

Damaged cable is a problem you don't always see right away. Insulation can be scraped or compressed in ways that show up later as electrical faults. A few habits prevent most damage.

Don't exceed pulling tension limits

Every cable has a maximum pulling tension rating, usually in pounds. Going over that rating can stretch or break the conductor inside the insulation. For larger pulls, a pulling tension meter helps you stay under the limit.

Watch the bend radius

Every cable has a minimum bend radius. Forcing it tighter than that can crack the insulation or damage the conductor. Bend radius is usually specified in cable diameters. For most building wire, the rule is eight times the cable diameter for permanent bends and four times during pulling.

Use rollers at every bend

Cable rollers at conduit entrances and on long ground runs protect the jacket from scraping. For overhead cable installations like fiber optic or telecom overlash, lashing rollers and slap on rollers keep the cable moving along the support wire without the jacket dragging.

Don't pull dry

Friction without lube is what causes most insulation damage. If a pull is harder than expected, stop and add lube before forcing it. Forcing a dry pull strips insulation and stresses conductors.

Inspect the cable after the pull

Once the cable is in place, look over the ends for nicks, cuts, or signs of stretching. Catching damage now is cheaper than chasing electrical faults after the system is energized.

Common Mistakes to Avoid

Two big ones come up over and over.

Skipping the lubricant

The most common reason a pull goes badly. Lube is cheap, takes thirty seconds to apply, and prevents most of the problems that come up during long pulls.

Pulling without a plan

Trying to wing it through a long conduit run with multiple bends is asking for a stuck pull. Spend a few minutes mapping the route, counting the bends, and figuring out where pull boxes might help before you start feeding wire.

A clean pull comes down to preparation. The right tools, the right lube, and a little patience save a lot of damaged cable and frustration on every job.