Dumb plumbing question about supply lines

[Dan Friedrichs]

I'm trying to install a pedestal sink where the drain and supply lines are somewhat exposed, thus I'm trying to use chromed pipe and fittings (rather than PVC and braided supply hoses). I've got the drain hooked up, but am having trouble with the supply lines. I'm using solid 3/8" brass lines with a flare on one end, which goes to the faucet fitting. The other end connects to the shut-off with a compression fitting. My problem is that the flared end leaks. Is there supposed to be some sort of gasket between these? What am I doing wrong?
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[John McClanahan]

I have never seen a gasket used there. It is a metal to metal seal. The area where the seal should take place may have a bit of a dent, preventing a good seal. Other than using a different chrome tube, one option would be to use a brass nut rather than plastic, so you can get it tighter.

John

[Dan Friedrichs]

Thanks, John - that's what I thought, but wanted to make sure. I'm getting really slight leaks on both the hot and cold sides, so I think it's a matter of not getting the plastic nuts tight enough. Does that nut have a name? I'll try to find metal ones.

I can see why people use the flexible lines, instead :)

[David G Baker]

The problem I have had with fixture plumbing is that I tend to over tighten them causing leaks. Not sure if that is your problem but it is a possibility.

[Rich Stewart]

Yeah, overtightening will make them leak. Tighten it up a little, turn the water on and continue tightening until the leak stops.

[Jerome Stanek]

once they are over tightened it is very hard to seal them I always use a little pipe dope on the before I put them together.

[Larry Edgerton]

Dan

I have had trouble with the ones you have that were bought at the blue box on a Sunday. I used to be a plumber, so it really drove me nuts. So, Monday morning I went down to the real plumbing shop and bought some Wolverine Brass [USA]supplies. End of problem.

I don't like those plastic nuts. Can't say if they work or not, I just always replace them. Also, I do as someone else has suggested, a thin film of pipe dope before putting them on.

Best of luck......

Larry

[Dan Friedrichs]

I bought new lines, put a little pipe dope on the ends, and only tightened them hand-tight, and they work! Thanks for the suggestions, guys!