Tony P says:

Hi Jim, From my experience in real life, poles are for the most part a maxium of 125′ between them or less, sometimes a little more depending on the existing landscape. If I did the math correctly (160th (N-scale)) of
125′ should be 9″ + or -. But varying the distance 1″-2″ either way would be more realistic due to fire hydrants and trees and driveways, etc. The use of thread is ok and should be black for newer construction or (green when bare copper turns green from oxidation)in older construction areas, 20 – 30 years ago and depending on the state you are modeling in. look up at the poles if you can in the area you are contemplating modeling in, if accuracy is that important to you or just go with black, that is always safe with pole and cable or wire construction. I plan on Tower lines (which will be thicker wires) going into a sub station, and thinner lines comming out of the substation to the poles to service the local businesses and towns. Tower lines have no coating on them, so they may have a green tinge to them or even a rusty look. newer primary wires top of pole usually have a black coating on them and secondary or bottom lines on the pole have black insulation on them. Tony P