Tape / dope on braided supply lines?

I thought I'd seen on the forum to NOT put pipe dope and/or plumbers tape on braided supply line connections... but now I don't find the reference. In any case... do these connections take dope or tape? My faucet instructions call for it but I've installed them w/o leaks and without tape or dope previously.

What is best practice on this?

Many of the braided hoses now have O-ring seals and as such don't need to be doped. If they use a metal to metal seal, a little pipe dope is fine but I would never use tape. IMHO tape is for sealing threads and on those hoses the threads don't do the sealing.

If it's a compression fitting, you don't use tape or dope.

The compression ring/ferrule seals the joint, over tightening is also bad news.

Tape and dope are for TAPERED threads, where the threads do the sealing.

Braided supply lines normally have a rubber gasket seal...tape would intefere. Some brands use a 'bullnose' which simulates an actual compression ring. It is for metal-to-metal seal, and again, NOT tape or dope



No tape or dope.

jimbo said:

Some brands use a 'bullnose' which simulates an actual compression ring. It is for metal-to-metal seal, and again, NOT tape or dope

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THe problem with the bullnose is that it is of a much harder metal and so does not truly simulate a compression ring, which as the name implies, compresses to seal not only against the tube but also against the machined tapers. Any imperfection in the machined faces can cause a leak.

And yet plumbers install them all the time without dope

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