How to straighten coiled, thick (4/0) aluminum electrical wire?
I bought 144′ of 4/0 AWG aluminum XHHW-2 wire (roughly 0.6″ diameter) that came in a coil. Probably because I didn’t unroll it the right way, it has the shape of a stretched Slinky, kind of a spiral. I cut it into the three 48′ pieces I need to run it through conduit into my house. To try to straighten them, I left them out in the sun for a few days and tried to rotate them against their spirals, and that helped, but they still hold enough of a spiral shape to probably make them very difficult to run through conduit. One way I expect I could straighten them would be to hang them from something tall enough with weights on the ends, but that’s not feasible here. Any suggestions?
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Wire needs to be uncoiled in the opposite direction it was coiled, not sideways off of the roll--or it will maintain the shape of a spring. Roll it out like you are pushing a tire. If that doesn't get it as even as you need, get some help to pull it across a round bar in the opposite direction of the coil. With smaller wires, pulling them taught across the perpendicular shank of a screwdriver will straighten them, something like a round fence-pole should work for larger stock.
Thank you, Quizzical. I realized I uncoiled it the wrong way shortly after doing so. I'll try pulling it across a fence pole.
If you really want it to be straight you need to run it thru a series of rollers.
You might find this video interesting.
https://www.youtube.com/watch?v=-Sj-vDn_O0g&ab_channel=TSRGarage
https://ahssinsights.org/forming/coil-processing/coil-processing-straightening-and-leveling/
Walta
Interesting, Walta; thank you. i hope I won't have to make a straightener like the one in the first video, but it's good to know about the option if nothing easier works.
Generally, when electricians pull wire from a coil into conduit, they don't first make it straight and then pull it through. They just pull hard enough that it gets straightened as it goes in. Something that big is going to be hard to pull. You'll probably need two people pulling and one person feeding it in. You'll also want lots of lubricant (specific electrical wire pulling lubricant that is certified not to damage the insulation.)
But if the spool is now beyond being curvy and is a tangled mess, you'll want it unkinked without nasty twists. That's the objective, not to get it to lay flat in a straight line on your lawn.
Thank you, Charlie. It's definitely not a tangled mess; the three wires are just retaining enough of their stretched-spring shape that they would curve in different directions as I would try to pull all of them through together. I increased my conduit size to 2" to make it easier, and I have purpose-made lubricant and a good pull rope.
tape them together before pulling them through. wrap of electrical tape every 2' or so
Thank you, stamant.
For 3 pieces of 4/0 2" is the smallest conduit allowed. You might have to go even bigger.
Are you sure? The calculator I am using show 2” being plenty. Am I missing something?
Is this stranded wire?
Yes, it's stranded wire. I shouldn't have said I increased my conduit size, as you're correct that 2" is the minimum. I must have been remembering that it was more than adequate, as the fill calculator at https://www.southwire.com/calculator-conduit shows a 27.03 % fill and a "Jam Probability 3.475382 (very low)" for three 4/0 and one 4 XHHW aluminum.
That is going to be a very hard pull, especially if you have even one 90. Make sure you have mule tape, lubricant, and maybe a pulley on the pull side. Copper is much more maliable and smaller for a service. I’m assuming the conduit is already down but you should consider upsizing if not. At least it’s short.
And an ounce of push is worth a pound of pull. It really helps to have someone pushing the wire in while another person pulls.
Agree about up sizing if possible. Also sometimes it's easier to run the wire through each piece of conduit individually and then glue them together rather than pulling through the glued assembly.