Am replacing a bathroom sink and noticed I don’t have a drainpipe that I have ever seen. It is some kind of steel and comes out of the wall about a foot. It is straight and has a nut on the end. The nut was connected to a 90 degree steel elbow threaded on both sides. The other end of the steel elbow was connected do the p-trap by a nut on the p-trap. So I took off the p-trap and elbow and now I have the drainpipe sticking out of the wall with a nut to screw onto something. I cannot figure out how to make it work with new parts. None of the replacment nut type plastic pipes will work. I would need something with threads for the drain pipe nut to go on to but then the other end would need a nut to connect to the p-trap. If I put the elbow back on, I am left with a threaded elbow. New p-traps also have threads so that wont work either. What can I do?

Quintty Flora

What you describe sounds like a long threaded pipe nipple with an El on the end to change direction. Most common situations would be a straight nipple of the correct length with a compression nut on the end to hold the P-trap. For a galvanized nipple you may need a flat rubber gasket to fit around the PVC P-trap. But sometimes you get lucky and there is enough chamfer on the inside of the nipple that a white nylon tapered gasket will work.

You should avoid a 90 degree El because that will slow the flow and may cause clogs. A 45 degree El is tolerable.

Basically you need a male thread for the compression nut that will hold the P-trap. I don't think you will need a Fernco fitting.