Well, the author hopes that Part 1 (below) suffices, about the tape that isn’t, and now feels it’s time to recommend how to best apply the stuff.
As much a difference as sufficiently polishing (cleaning) copper components means for no-leak sweating success, the same goes for the cleanliness of threads, both male/female, regardless of diameter and regardless of material. So we’ll do this wrapping routine with this also in mind.
Let’s start this training exercise with a ½-in. or ¾-in. pipe nipple, 4-in. or longer. It could be a galvanized one, a brass one or a Schedule 80 PVC threaded nipple. Are you right or left handed? The author happens to be right handed. If you are LH, I hope you have become a sufficient RH/LH translator/transcriber by this stage of your adventure.
Let’s also pretend you are me, and we’re sitting on an up-turned 5 gal bucket in an unfinished bathroom or maybe we’re kneeling down on a mature tile floor removing the lavatories corroded ½-in. galvanized, hot supply nipple. (The hot ALWAYS goes first.) In both situations a new nipple needs to be inserted into empty female threads, in front of us. (I don’t know about you but my favorite knee pads are those made for carpet install pros. They’re thick, genuine leather with thick felt liners, with double leather straps and metal buckles. Very comfortable and no sweating.)
PtP carries around old toothbrushes and new, standard trade, hog-hair paste-flux-brushes for cleaning threaded female fittings. He also has pipe taps to quickly run in and out, which dislodges stubborn foreign matter and dresses imperfect threads. (See: The PEX Revised and Expanded Edition of Plumbing A House for some suggestions on the use of fittings for fuel gas systems.) Of course male threads are easier and quicker to clean in preparation for engaging pipe to fittings and vice versa. But equally important is always starting with clean female threads.
So, Here We Go!
For this tutorial I’ve chosen a new ½- or ¾-in. Schedule 80 std. right hand threaded PVC nipple. I’ve made this choice for the easy-on-the-eyes gray color, and if recently purchased from the supplier, the threads will be as clean as a whistle, and dry. We will work with a roll of quality ½-in. tape. The length of the tape on any spool will vary, by price. Hardware stores will tend to sell rolls with less on them for customers with only occasional needs but usually only serious hardware stores will carry 3.5 Mil, 99% pure tape, what we want for this exercise.
Also, many tradesmen opt for 620-in. rolls, as does yours truly. The 1,000 plus-inch rolls (like Blue Monster) which have become popular these days, might pose a bigger challenge for the new-learner unless they had large hands and long fingers. Pete the Plumber recommends the 620-inch rolls which he (with gorilla mitts) finds more comfortable to manipulate, and would think so especially for new learners.
O.K., Lay It On Me!
As hinted in the first paragraph, from here our second push might qualify for some readers as sickeningly elemental. That’s alright. The author was always ‘queasy’ for a day (or longer) after lifting the lids on Greasy Spoon Restaurants’ grease traps. I ‘m going to be very anal in this second push because I would be happy if this post could really put the ribbon seal topic to rest.
Fine. We’re comfortably either standing, sitting, or kneeling. In our left hand, palms down, fingers are wrapped around the nipple (of which about 1¼-in. pokes out past your thumb and forefinger, into space.) With the tape cover off find the end of the tape and pull out 2 inches. Place the spool on your right index finger. Have the tape hanging off the back side of the spool. This is very important because it affords you better control. Now, on the same hand, grip the bottom of the dangling tape between your thumb and middle finger.
Next, bring close up, the nipple in your left hand, towards you, from behind the tape, and approximate the bottoms of tape (in your fingers) and bottom of the nipple. Now on the spool hosting hand, separate middle finger and thumb, and let the tape hang free, so it hangs in front of the nipples threads. We’ve draped the dangled tape in front of and over to the edge of the threads. You want the outside edge of the tape to be right at the edge of the nipples first thread, that is, the one at the front edge of the nipple. And, we want the tape not to hang below the bottom of the nipple.
When you’ve got that, still holding the nipple firmly, lift your thumb on that left hand and move it over and press the center of the tape tightly, in place. Keep your thumb on it firmly; don’t let it slip.
Now, with the middle finger on the spool-hosting hand, pressing on the far, back side rims of the spool, and the thumb pressing the front (acting as a brake), pull the tape (away from you) out over the top of the nipple, letting out about 5½ inches of tape, and stop. Next, pull on the tape with some ‘good’ force. Don’t worry if you break it. We’ve gotta whole roll to play with. We’re using quality 3.5 Mil, 99 percent pure PFTE. (Those attempting this with the cheap stuff will have a much less satisfying experience.) Maintaining this pulling tension, in a circular path, slowly lower your spool hand down until you can plainly see the top threads of the nipple, in high relief, under the tape. Good. Then maintaining that pulling tension, bring the spool forward, towards you, (below the nipple), and begin to encircle the nipple in this clockwise direction slowly, maintaining tautness. When you are bringing the tape upwards and about to reach your thumb, lift the front edge of your thump so you can go under it and keep going until you go around once more, and are about to reach it again. At this point you should be able to remove your thumb as you climb up the threads, overlapping by one-half tape width as you climb to the top thread. Almost done. Once at the top thread we will keep winding, this time back down, lapping as you go, until you cover our very first wrap, where we started. Maintain the tension. FINALLY, put your left thumb back on the tape FIRMLY. (The higher the quality of tape the more of a chore this becomes.) Now, we want the shortest distance between spool edge and nipple. We will finally separate the tape. This is done by tightly gripping the spool with thumb and both fingers, and pulling the spool away from the held-in-place nipple with a jerking motion. If you pull slowly you will merely stretch the tape too far before breaking it. You can also employ a jolt of near-equal force in opposite directions if it’s easier for you. After the tape breaks, keep your left thumb firmly pressed on the tape and set the spool aside. Finally, (yeah, finally) using your right hand thumb and index finger, do a forceful twisting (only in the same clockwise direction) of the tape-end into the thread’s valleys. With good force the tape end will adhere. With the tape lying flat and no unraveling, it’s time to pat yourself on the back. CONGRATULATIONS!
Just In Case
Another way of parting the tape that works for me is to hold the nipple still, left thumb firmly on tape, and wind up the spool, tightly, until the rims of the spool contact the nipple, and then keep winching on the spool until the tape parts. When attempting either parting technique, with the cheap stuff, when it parts, there can be an ‘explosion’ of micro-fine, wispy, strands of PTFE floating in the air with some still attached to both pieces, stretching like boardwalk salt-water taffy as you try to break it/them. There are other unsatisfactory aspects to the cheap stuff. If the side of the spool does not have the Mil-Spec # or the A-A- sequence, it’s the imposter. This stuff is rarely wound onto the spool in level wraps and it often, what PtP calls ‘gutter-balls’, slides into the gap between tape edge and inside wall of the spool. Once it has done this, it is no longer in tape form. Several inches of tape have become string. You cannot get a ‘string’ end to adhere to the already wrapped threads. And, it makes for awkward moves to join fitting and pipe and vice/versa, without having the tape unravel during the engagement. Another futile effort, like trying to put toothpaste back into the tube: putting the roll cover back on the spool of the cheapest of the cheap is an open ended finger exercise. Forget it. It was a one-time joint. Without the spool cover a good portion of this roll will many times unwind between needs, and, be wasted. Finally but not a finally: the cheap stuff, when held up to view, looks the color of skim milk compared to the cream of quality.
What If I Wrap The Tape On Backwards?
If you do not follow the spiral direction of the threads (clockwise when staring down the barrel) upon engagement, in most cases, the ribbon tape is scraped up into a leading wave of white, a bow-wave, forming at the edge of the fitting, making for a dry and leak compromised joint. I don’t know anyone who hasn’t done this even long after they thought they “had it down.” You’ll be excused. It won’t affect your grade. It’s gonna happen. But NOW you know how to make it right.
What About Oily Threads?
O.K., the former exercise was performed on a clean, PVC threaded nipple. What about galvanized or black steel pipe? The answer lies in whether you are buying the pipe pre-threaded in lengths of one through ten feet, and using store-bought nipples, or are you making your own threads with your own threading equipment?
Store purchased sticks/sections and nipples are usually acceptably oil-free and other than inspecting the threads prior to engagement, the ribbon can usually be applied without a further cleaning of the male threads. When making your own lengths and nipples, however, usually there is enough residual oil in the threads that it is a good idea to wipe the excess off before applying the tape.
How Many Makes For A Bum Wrap?
You will see in ‘the literature’ recommendations that 3 wraps of tape is recommended. The author finds his described process is foolproof because he also applies a thin application of paste joint compound to the threads of female fittings. When working with DWV female ABS plastic threads (FIP adapters) and ABS p-trap union threads, the pipe joint compound has to also be PTFE. (See below.)
For most applications, sans the paste, I am in agreement with the 3 wrap stipulation if you do not want to employ my above method. However, when you encounter broken and/or ‘slightly’ damaged threads, metal or plastic, it’s O.K. to apply more wraps. Again, as I mentioned upstream, one of the few times/places that I sometimes forgo the use of tape is on the fine threads of 1¼- and 1½-in. threaded brass tail pieces under sinks and tub waste & over-flows, if I have any difficulty engaging these threads. They are so fine and shallow that it is possible, too easily, to cross-thread the parts. Here, on metal parts, without the use of tape, I use either Hercules® Brush-On BLOCK™ paste thread sealant or Rectorseal® #8 thread sealant. If ABS plastic parts are involved, male or female or in any combination, the author employs Rectorseal T Plus 2™ paste (PTFE) sealant. DO NOT USE the Rectorseal® #8 WITH ABS, IT CAN DEFORM THE THREADS. On PVC pipe and fittings, because the material has great chemical resistance, the #8 is O.K.
O.K. I think we’ve covered most of the bases except for mentioning a few “special cases.” The first one I’ll mention will be: PVC pipe, nipples and fittings.
This plastic, PVC, is so slippery to begin with that when adding PTFE ribbon tape to the mix, ole Gorilla Mitts used to occasionally split fittings by over-tightening them, by hand. Two-pairs of 10- or 12-in. slide-jaw pliers (See The Straight Poop, A Plumber’s Tattler, or…either of my Taunton soft-covers to view these pliers. They’re also shown in the newly Revised PEX Edition, Plumbing A House, e-version.) These two tools allow you, with the aid of PTFE ribbon and paste, and a handsaw for plastic or a chop-saw with a blade for plastic, to assemble threaded Schedules #40 and #80 PVC pipe & fittings, up to 1½- and 2.0-in. in diameter, with perhaps a little too much ease.
Second loose end. When taping pipe and nipples for metallic fuel gas systems, make sure to start wrapping the tape on, one thread higher up than we did for our PVC practice nipple. If you create ribbon slivers (which you do not want on gas and compressed air systems, which we touched upon up-stream), it’s when you run your tape too close to, or overlap the first, beginning thread. A little swipe with the pipe joint compound’s ‘BRUSH IN CAP’ brush, across the female threads of the female fitting, will make up for the naked first thread, and even further your chance for fewer or no leaks.
Third loose end. When taping the male threads of 1¼- and 1½-in. ABS and PVC trap adapters (sink wastes), run the tape well enough past (overlap) the first thread on the end of the male fitting to allow you to fold the tape over and roll it down the inside of the inlet barrel of the adapter for maybe an ⅛ to ¼ in. Regardless of whether you employ the beveled nylon slip-joint washer (Installing And Repairing Plumbing Fixtures) or the now common, combination (one piece)‘beveled-nylon washer and slip nut’, or, the simple, old-fashioned, square-cut, rubber slip nut washer in combination with the chromed brass tail piece, this ‘tape-tuck job’(wish it’d be as easy for my bulge) provides a solid bonus to attain the ‘No Leakers Club’ membership.
Fourth And Last. (Not because I exhausted the list, but because I fear I’ve over-challenged your patience.) Some of you may want to become handy at residential plumbing maintenance or maybe you live with tub and shower valves (or wide-spread lavatory faucets) that employ standard, compression washers on screw stems, and you want/need to do ‘drip repair duty.’ This type of valve employs packing nuts. (See: The Straight Poop.) When adding string packings around the stems, under this nut, do the same as we did for the trap adapters: wrap the tape fully over the threads and then overlap so you can fold it under the bottom edge of the nut. This helps to evenly apply pressure to the packing for better stem-leak protection. See ‘The Poop’ for wrench use adjustments.
Well you know what? If you’ve hung with me all the way down to here, you also deserve your own growler of Newcastle Pale.
Adiós Amigos. Let’s meet up again.
Peter Hemp is a San Francisco East Bay residential plumber and plumbing author and former R & D steam vehicle plumber. His hobbies are ocean kayaking and touring the Left Coast by bicycle.
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