Plumbing opinions: Anyone have an opinion on teflon tape vs pro-dope sealants?

[HamdenRice]

I'm installing a shower/bath body and several connections will be threaded copper adapters into threaded copper adapter, or threaded copper adapter into brass.

I'm planning to use teflon tape on the advice of a local plumber, but "grew up" on pro-dope.

Can't seem to find anything really about this on the net.

Another local plumber told me he uses both together! I've heard that was strictly verboten.

Any opinion?

[Kingshakabobo]

1. Check out this website....

http://www.plbg.com/

This is a fun site where several pros post. I believe they have had this argument in several threads. Scroll through but I THINK the consensus is to use both, IIRC.

Anyway, it's a strangely fascinating site.......almost as fascinating as the 9/11 dungeon....:)

[HamdenRice]

2. That's funny, 'cause

Since I posted the OP, I found a few plumbing forums. I was googling the wrong search terms. "Plumbers tape" and "compound" returns more relevant sites that "teflon tape" and "pro-dope".

Anyway, one poster confidently said use both, another few said, whatever you do, don't use both.

I gathered from the more analytical posts that they are pretty much both effective, but that dope is more messy, and that the harder the pipe the more appropriate dope is (because dope is so slippery that if you use it on something soft, like pvc, you are likely to over-tighten.

Also, if you use tape incorrectly, you will get tape fragments in your water which can clog filters, but if you use dope you may get a dopey taste/smell.

Decisions, decisions!

Since I'm using copper pipe with sweated male and female threaded adapters, I've decided to use tape.

Thanks for the site and input.

[Kolesar]

3. The dope and tape functions as a lubricant more than a sealant

It allows you to turn the joint down quite tight. The seal is between the two metal parts. Remember that a pipe thread is a tapered thread and that as you turn it in, you are going to get absolute contact and interference to close up the joint.

[HamdenRice]

4. Plumbing can make you head explode

I had read that -- that both are basically lubricants, not sealants. But then a google search led me to a Wiki article that looked very officially written. I think it was under the title of something like American standard threaded pipe.

It stated that certain kinds of tapered pipe does as you state -- make a complete seal. But that ordinary threaded pipe, like galvanized and threaded copper adapters that are commonly used in residences for water supply, are not tapered, and there is not a metal seal. These use dope or tape to make the seal. The tape or dope is both a lubricant and a sealant.

It argued that tape deforms in the threads and is water resistant, leading to the seal. So I chose tape.

[Kolesar]

5. I have done a lot of taping to good results (as a homeowner, not a professional0

I have this "trick", where I lay the tape on the threaded pipe in such a way that it will not unravel as you tighten the nut. One way to describe it is: "put on about 1.5 wraps of tape, so that the nut will not cause the tape to unravel as you spin the nut on". Does that make sense? If you have the loose end of the tape coming toward you, the tape will get "picked up" by the nut and jammed in the threads. Sort of like when you put your jacket on and your sleeve gets pushed up to your elbow. It helps to moosh the tape down into the threads with your fingers before putting the nut on. It can be very frustrating. Like Sunday when I thought I was going to replace the wax ring on the toilet drain in an hour and a half and next thing you know I am down at the hardware store buying shims because "it has to be level"...and what I wanted to do was to be done by 1:00 so I could take a shower and drive downtown where my activist buddy was having a film shown at the Film Festival. Well, that didn't happen. I was done at 3:00 and just sat on the couch because my back ached from lifting the toilet and then crouching in that tiny corner scraping the wax and trying to bore one more hole through the tile to mount that ring that was rocking. Well, I broke the bit so I gave up on the drilling. It was a good thing that I had a bottle of red and Bad Santa was on that night or I would not have had any fun.

The toilet looks nice now, though. I don't think I will put this in my journal.