Plumbing Tips- Teflon Tape, Pipe Dope, Channel Locks
Posted by Wayne
As I’ve mentioned several times before, back in the day I fancied myself a plumber. This was a very valuable experience and I learned these 3 handy tidbits which I will now dispense:
Teflon Tape
If you’re bold enough to be doing DIY plumbing, you’re probably aware that you need to use teflon tape to prepare any metal threads on a ‘male’ piece before screwing it in to a ‘female’ fitting. I can’t think of any exceptions to this, except when you’re joining two plastic pieces you’ll probably want to use pipe dope only (see tip #2 below). The teflon tape basically squashes down into all the little crevices in the joint and prevents leaks.
What I didn’t know was the proper way (and direction) to apply the tape to the pipe. If you wrap it in the wrong direction it will come unraveled when you try to screw the male piece into the female piece. For me at least, this is very tough to figure out just by looking at the two pieces and envisioning what is going to happen when they get screwed together.
My first day on the job I learned what is the correct way to apply the tape: Hold the pipe in front of you in your left hand, use your left thumb to hold the tape in place as a starter, and then wrap over the top of the pipe (clockwise if you’re looking at it head on). You just want to wrap it all the way around 2-3 times, and then press the tape again with your left thumb and pull the tape roll until the tape stretches and breaks. If you do it this way, you’ll know for sure nothing will unravel when you go to screw the two pieces together.
Pipe Dope
Ask a pro and they will probably all tell you that in addition to using teflon tape they will also use pipe dope on the fitting. It virtually guarantees you’ll have a leak-free seal every time, and it lubricates the joint so it’s easier to put together and take apart (50 years down the road someone will be thanking the thoughtful plumber who used pipe dope). When joining two plastic pieces together, applying teflon tape may cause the joint to be too tight, so you can get away with using pipe dope by itself.
The pipe dope is applied in a thin layer after the teflon tape is applied. You’ll want to apply the pipe dope in the same direction as the teflon tape so the tape doesn’t unravel.
As a plumber we used the pipe dope that comes in a can like the image shown above. This is more pipe dope than a DIY’er could use in a lifetime, but it is nice because it has a brush attached to the underside of the lid. For my projects I bought a small tube of this stuff and it can be applied with a finger.
Channel Locks
Channel lock pliers are used extensively in plumbing (often in pairs), but I never really saw the full benefits until I learned how to use them properly.
The first step in using them properly is that you want to adjust the size of the channel locks around the pipe or fitting so that the distance between the two handles on the pliers is minimal. This makes it easy to grab, you’ll have better leverage, and if the channel locks should happen to slip you’re less likely to have a finger or skin get smashed in between the two handles when they snap shut. Oh yeah, don’t put your fingers or hand skin in between the handles.
The second thing I learned, and I don’t think this is extremely obvious, is that channel locks have a “direction”. They only really work if you’re pushing/pulling in the correct direction because the teeth of the pliers are oriented in one direction. If you clamp on to a horizontal pipe with a pair of channel locks, and you’re holding the channel locks right side up, and you start pulling up, the teeth will not grab and it will slip. The direction that you’re pushing/pulling with channel locks has to always be towards the bottom handle. See the image below for an example:
If you’re using two pairs of channel locks they have to work in unison, with the pressure on both pairs being applied towards the bottom of the pliers. If you’re using channel locks correctly they will almost never slip (the harder you’re pulling the deeper the teeth will dig) and you won’t get any smashed fingers or pinched hands.
3 Responses to “Plumbing Tips- Teflon Tape, Pipe Dope, Channel Locks”
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February 27th, 2008 at 2:18 pm
Wayne - Awesome post - I learned three new things today.
February 27th, 2008 at 3:09 pm
Thanks Mike!
I learned all three of these things in the first five minutes on my first day as a plumber. They’re handy to know, but for whatever reason they don’t seem to be common knowledge.
March 30th, 2008 at 2:25 pm
Great tips! Might seem obvious to someone working in the plumbing field, but to a DIY’er these nuggets are gold!