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I need to fish three 12 solid THHN wire through a narrow (old building) metal conduit with 90 degree bend.

I'm shopping for fish tapes and there are several different materials, and I don't know which one is best (in general and for my purpose).

I've seen these fish tape materials: fiberglass, polyester, steel. There are also different tips.

Could someone please explain what are the differences, if there is one better than the other (in terms of easier to use), and finally what would be the best option for my application?

Thank you!

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  • define narrow. How long ie distance. where is the bend? middle? at an end?
    – Solar Mike
    Jun 29, 2021 at 15:49
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    FYI Stranded wire is easier to pull but costs more.
    – JACK
    Jun 29, 2021 at 16:17

2 Answers 2

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It sounds like regular old 1/2" (trade size; really 5/8") EMT conduit. That stuff is easy to work with. You don't need to make a Federal case out of it.

In simple runs with 0-1 bends, I like to tape the 3 wires together (staggered, with the longest bent slightly toward the middle so it resists hanging up on edges) and just push it through. That works more than half the time.

You can tie a string to a little scrap of plastic bag and use a vacuum cleaner to suck the string through. Then use that to pull through a stronger string (if that's even necessary) and then tape that to the wires and pull them through.

Don't scrimp on electrical tape when binding the tape to the wires. I like to have about 6" length binding string to one wire, then about that length binding to the other wires.


If you are buying fishing tape because you like to collect stuff, then buy nice fishing tape. It defeats the purpose of buying stuff if you buy crud and then have to replace it on the next job because the crud isn't good enough for the next job. The #1 thing you look for is non-conductive material, so when you are pushing the tape into a main breaker panel or other setup where part of the panel cannot be de-energized, you don't get a fireworks show when you push the tape into the hot conductors or if it slips out of your hands (or worse, doesn't :).

The tips are for tying onto various pulling implements and onto the pulling baskets that are used to attach to wires when you're pulling the big stuff. Other than that, the specs to look for are pulling strength.

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  • Thank you. My question was edited (not by me), and I wanted to know the differences between these fish tape materials (fiberglass, polyester, steel, etc.)
    – igorjrr
    Jun 29, 2021 at 17:12
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If you're pulling through metal conduit, steel fish tape will be the most difficult to pull due to friction between the conduit and the fish. And steel fish tape is conductive, so you have that risk factor to deal with.

For pushing through (difficult) metallic conduit, I personally prefer the coated and twisted modern polyester. I feel like it gets stuck less often on any corners or rough edges, whereas fiberglass just digs in harder. But that's just my opinion. Plus with the twisted tape not being just round, sometimes you can turn the tape and it "walks" sideways past whatever friction is holding it in place.

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