Sink outlet problem

[supertaf]

Not very au fait with plumbing but have a small problem. Outlet on sink was leaking into cupboard below. On investigation, the pipe is hanging loose from the bottom of the sink meaning that some water goes down the pipe and some goes into cupboard. Thing is I can't see how it ever fitted, it seems that it was just stuck to the sink bottom with black `gunge`!!! There is no threaded part or anything. Is this normal and what should I do?
Thanks.

 

[ChrisR]

Butler type sinK??
Take what you can to a plumber's merchant and ask. NOT a diy shed!

 

[supertaf]

Now you're asking, it's a flush fit sink but can't see any brand name on it. It would be difficult to take anything to anywhere to be honest as it's all in situ - i have wedged it up against the bottom of the sink so that it doesn't leak for now. I'm just puzzled as to how it was ever fitted....

 

[bab]

Theres only 2 main types to fit banjo slotted brass waste or top grate with a centre screw into the waste bottom that the trap fits on to. if there was a plasic or alloy nut on a banjo type it may have perrished & fallen off.