I've got a new basin and tap for the nathroom. When I went to connect the pop up basin waste which came with the tap to a fairly standard looking bottle trap I found that it wouldn't tighten up. The threads fit, the pipe is the same size and it should all go together but the plastic compression nut on the bottle trap can't be tightened enough as there is another nut on the side of the waste where the pop up waste control rod goes in.
Am I missing something or do I need a specific type of trap?
Am I missing something or do I need a specific type of trap?