"Lets start from the beginning. I put in a new faucet and decided to change the pipes as they are all rusty and corroded. The drainage pipe is the one giving me problems. I cannot get the nut off to install the new pipe. The old nut is metal and is corroded onto the drainage pipe. This is where the water drains out into the sewer system right next to the wall. I cannot twist it off and cannot figure out how to cut it off. Any help is gratefully accepted. Thanks Anita"