Is this iron pipe lamp grounded/insulated enough to be safe?
Most lamps have a two-prong plug. All the lamps in my house, even the ones with metal casings, have two-prong plugs. I don't think you have a safety problem.

However -- if I were building this lamp, I would attach a three-prong grounding plug and cord, just because the aesthetic of the lamp is so obviously 'heavy industry' and most heavy industrial equipment is fault-grounded.

In order to do this, you would need a grounding lamp kit. It's better and cheaper to purchase the whole kit, but if none is available, you can safely substitute a three-prong grounding plug and cord into the kit shown in the Home Depot tutorial.

You will also need a grounding locknut, also known as a bonding locknut. These are widely available if you know what to ask for.



I think the design calls for a hole through the pipe, but the rest of the project requires no cutting or drilling, and the hole is not strictly necessary.

Hole option: before beginning assembly, drill a 3/16" hole into the side of the 3/4"-to-1" coupling, through the 1" section. Drill about 1/4" from the end, or just clear of the reinforcing flange. Chamfer the ends of the hole because you will be feeding a wire through it later.

In step 9, you thread a 1/2" grounding locknut onto the 1/2" close nipple, or thread a 3/4" grounding locknut onto the 1/2"-to-3/4" coupling. Snug it up tight. The threaded rod from the lamp kit may have a hole for the ground wire. If so, pull the wire out through the hole now.

In step 12, if using the hole option, feed the fault-ground wire from the grounding lamp kit out through the hole. If not using the hole option, bring the wire out through the open end of the 3/4"-to-1" coupling. Strip the end of the fault-ground wire and attach it to the screw on the grounding locknut.

The pipe assembly is now safely connected to the round pin on the three-prong plug.