How can I pull a wire through a pipe that has too many turns for fish tape?

As a wireman with 30+ years of experience, I've had to do lots of tricks to complete the task. While a vacuum and rat (plastic bag) works most of the time, it sometimes fails for many reasons. You might want to go the opposite of that idea. Get some nylon string and a living rat from a local store. Be sure to size the rat for the specific size conduit. Get some compressed air from somewhere. I have known them to run 1/4 mile before. And the rat will go fast. Have a helper to dole out string as it enters the conduit. It's best to have a good lead laid out on the ground, because when you start, the first hundred feet will be run in seconds. Good luck ?

Another trick that works is to use weed-whacker line. It's essentially really thick monofilament and it turns corners better than fish tape. I've used a lot of it on my boat to pull wires.

In the past I have used

• micro RC cars - tie the string to the body and drive.
• hexbugs - (A hexbug is a small oscillating, buzzing "robot". The oscillation in combination with its flexible rubber legs makes it move.) tie a string to it (lightweight monofilament) and go for a cup of tea, come back when the bug has gone through the conduit
• magnets - one tied to the end of the string one outside the wall to pull it through the pipe, doesn't work so well on ferrous pipes :D
• hoover with a bag and string - as described above
• small fishing float - tied to a light line, close the "bottom" end of the pipe, flood it and watch the float come up voila pipe traversed.
• leaf blower and bag and string - similar to the vacuum, more fun to do though, and seems to develop more pressure for pushing the bag.
• bearded dragon - put him in one end, release live food at the other and off he goes.....just remember to tie a light string to a harness or its basically just a fun run for your lizard! (guilty!)

Hopefully some of these can help you, maybe not the bearded dragon for that size of pipe though.

Had a vertical drop on an HVAC oval return duct with an S curve that had a 2 foot horizontal run. I used a real fishing pole and put a tiny fishing hook into a ping pong ball. I gave the line plenty of slack and dropped the ball in. After a few tries, it bounced through the S curve. I then used the fishing line to pull through a stronger small rope. I then used the stronger rope to pull the wire.

We just pulled 3 THHN-2 gage 2 (two power one neutral) and one THHN-2 gage 6 for ground through about 25 feet with two wide angle 90's (normal 90 degree but not abrupt) and one 45 degree. Luckily we put all the bells in the same direction. Even the wire would not go one way. We tried putting the fish wire in the other way and the pulling no luck even on the first 90 degree. All the bells were going one way so we were lucky. Then we put the fish wire the way it would go (easy way) and pulled a small nylon rope through. Then we did not use the fish wire again and used the thin nylon rope and pulled on the "easy" way. Went at about 2-3" per pull no problem. So there is an easy way to pull and an impossible way. The easiest way you get the fish wire though is the easiest for the wires as well. so you need to put fish wire through easiest way, then pull the rope though, then tie the rope with electric tape, then pull the way you got your original fish wire (easy way) through. At least that worked for us.

I use a rodding spring line aka drain cleaning cable that I use to unblock pipes to thread cables.