I found a nice vintage bridge type lamp in the dumpster and I am trying to fix it. It was thrown out because the socket was shot
I am also trying to replace the line cord with a new polarized one. I know how to wire the lamp but I am having trouble getting the old cord out of the lamp pipe. The pipe is the standard lamp pipe (1/8" IPS Pipe) Is there any tricks of the trade on how to get the old cord out and be able to fish the new one in with minimal problems?
Here is the lamp part I am dealing with





Thanks

Assuming you would be able to pull the old cord out, you can tie very securly the new cord to the old and use the old one as a fish tape to thread the new cord in place. I don't know if that is doeable in this case, but might be worth a try.

Thanks I never even thought of that but the problem is the old cord will not move at all

It might be caught (and the isolation cut into, so thats what is holding it) in the sharp bend in the joint (image 1) - probably on the far end of the threads

So try to push it in here (so it does not contact and pull against the metal in that corner), while pulling on the other side

Insert a piece of plastic or cardboard between the sharp edge and the cable. This will also prevent damage to the new cable when inserting it, and allow you to push on this side (so less chance to damage the new cable on the same location)

Solder the new cable to the old, this way you get very strong connection but which has no thickness so will go easily through everything



If the light is hot (incandescent o HID), insert high temp isolation sleeves over the wires on the end thats near the lamp, so the heat cannot degrade the isolation to the point where it shorts to the metal

The following is 240V locations (Europe etc) electrical code, but i think is good for you too : If you use cable with 1 layer of isolation on the wires, connect earth to the metal. If you use cable with 2 layers of isolation (as in - 1 more external layer over the 2 wires) and everywhere else the isolation between live electrical parts and the outer metal is double (and both layers are appropriate durability), then its safe to not connect earth

 have you try dish washing soap. or wire pulling grease from electrical supply.
 some time when wire get old and brittle making hard to pull.