Quote Originally Posted by NeonMoon View Post
DD, black and galvanized pipe will have a tapered thread. The threaded end of the pipe may bottom-out on the deck of your boat before it tightens in the floor flange. You might want to cut some of the threaded end off so the tapered threads will seat in the floor flange, as opposed to the end of the nipple bottoming-out on the deck.

If all that makes sense.
That is why I put the lock nut on it. I was afraid I cut a hole into the carpet or wood trying to screw the pipe all the way tight.