"ping" sound when tightening compression joint

[plodder]

I've just done my first set of compression joints. twoof them had tiny leaks. I tightened the nuts another 1/4 turn. in each case I heard a barely audible ping sound. Is that a good thing or a bad thing? is it the sound of the olive clamping tightly on the tube to make a good joint OR is it the sound of the olive deforming and making a bad joint?

Both joints are still leaking very very slightly since I tightened.

any help is very welcome

thanks

 

[TexMex]

Probably just Brass against Brass friction.

 

[MANDATE]

I think the noise stems from the rubbing of metal to metal, this could be on the threads or it could be the olive to 'nut'.
It isn't anything to worry about although a single drop of oil would most likely prevent it.
The problem regarding the leaks depends on wether or not they have been under or over tightened. I also find 'copper olives' being softer than 'brass' are easier to work with, I usually under tighten them to start with and adjust them after the water pressure has been applied till any weeping has been eliminated. In your case I would dismantle and wrap a couple of turns of ptfe tape around the joint line between olive and pipe.
The escaping water is passing between olive and pipe or olive and housing and ptfe on the olive will stop both.

 

[GRACEFUL SAVAGE]

Pipe might be in at a obtuse angle, so no matter how much you tighten it the olive it will not sit in the shamphered brass female part. try doing what the guy said before me with the ptfe tape(have hold of the threaded fitting in left hand,and have ptfe in right hand make sure the tape goes on using full width of the tape rotate in a clockwise motion round the fitting,with the tape right next to the fitting)
If the pipes are under too much stress or there is a bit of grit in the fitting or hasnt been brushed with wire wool your wasting your time....E.

 

[plodder]

thanks for all of your advice. in the end I think the stress on the pipework may have been too much coupled with the obstuse angles. Ive replaced the compression fittings with tectite (which I have everywhere else on this project) and they work like a charm - not a single leak in the whole project. No more compression fittings for me!

cheers