I have just replaced a mixer basin tap, however there is a slow drip from the connection between the water pipe and the copper tail. I have connected both pipes using a straight compression coupling. On closer inspection the old nut on the original pipe has a crack(probably through my overtightening)which is where i think the leak is. I am looking to replace this nut, however it is not able to just slide off the pipe. The obvious answer is to cut the end of the pipe off and remove the nut, however this will mean the water pipe will be that much shorter - from here how to I go about reconnecting the two pipes??