Question just about the order of pipe dope sealant and teflon tape

[Danny D]

Q: Does the order of the tape & pipe sealant matter?

Starting with this:
http://www2.picturepush.com/photo/a/12901000/img/12901000.jpg

Just wondering, if, for critical 2" PVC applications such as
pool equipment, when using *both* pipe sealant & teflon tape:
http://www5.picturepush.com/photo/a/12900978/img/12900978.jpg

Does it matter if we put the teflon tape first:
http://www3.picturepush.com/photo/a/12901031/img/12901031.jpg

And then the pipe sealant?
http://www1.picturepush.com/photo/a/12901034/img/12901034.jpg

Before screwing the fitting into the housing:
http://www5.picturepush.com/photo/a/12901038/img/12901038.jpg

Just curious:
Q: Does the order of the tape & pipe sealant matter?

[HeyBub]

I'd use one or the other, not both.

Teflon is primarily a lubricant and is most effective on NPT fittings. NPT
fittings change their pitch so that the connected pieces deform the pipe
threads more and more making the seal.

Other types of threading do not change the thread pitch (if there is any
involved in the seal), so any imperfections are better dealth with by a pipe
sealant.

[bob haller]

a plumber friend uses tape and then dope, on every joint to avoid leaks

[Ed Pawlowski]

On Sat, 11 May 2013 05:26:00 -0700 (PDT), bob haller <hal...@aol.com>
wrote:

>
>a plumber friend uses tape and then dope, on every joint to avoid leaks

Does he wear a belt and suspenders too?

I know people that use both, but I know people that use one or the
other and don't have leaks. One advantage of tape is when you take it
apart five or ten years later, it is probably going to be easier.
Joint compound can get hard.

[Stormin Mormon]

Actually, I do both. Tape, dope, belt,
suspenders. For real.
.
Christopher A. Young
Learn more about Jesus
www.lds.org
.
.
"Ed Pawlowski" <e...@snet.net> wrote in message news:d8fso8pvuto266ltr...@4ax.com...

[tra...@optonline.net]

On May 11, 8:46 am, Ed Pawlowski <e...@snet.net> wrote:
> On Sat, 11 May 2013 05:26:00 -0700 (PDT), bob haller <hall...@aol.com>

> wrote:
>
>
>
> >a plumber friend uses tape and then dope, on every joint to avoid leaks
>
> Does he wear a belt and suspenders too?
>
> I know people that use both, but I know people that use one or the
> other and don't have leaks.  One advantage of tape is when you take it
> apart five or ten years later, it is probably going to be easier.
> Joint compound can get hard.

I use one or the other too, never both. Usually I use tape. And I
rarely have a problem.

[Vic Smith]

On Sat, 11 May 2013 04:30:52 +0000 (UTC), Danny D <Dan...@example.com>
wrote:

According to this, tape is a no-no
http://www.lascofittings.com/supportcenter/TheDosandDontsThreadedPlastic.asp.

[tra...@optonline.net]

> According to this, tape is a no-nohttp://www.lascofittings.com/supportcenter/TheDosandDontsThreadedPlas....- Hide quoted text -
>
> - Show quoted text -

That's a good find. What they are saying makes sense and they
should know. I've used tape for years and rarely had a problem.
But part of it is probably because I know how much to tighten them
and don't over tighten a fitting to crack it. For the future, I'll
use
joint compound.

Also, the part about Sched 80 vs 40 was interesting. Particularly
the part about how any threaded PVC joint reduced the overall
pressure rating by 50% compared to all glued connections.

[cl...@snyder.on.ca]

On Sat, 11 May 2013 05:26:00 -0700 (PDT), bob haller <hal...@aol.com>
wrote:

Pipe or dope - not both. Read the instructions on either one.

[Danny D]

On Sat, 11 May 2013 08:22:29 -0500, Vic Smith wrote:

> According to this, tape is a no-no
> http://www.lascofittings.com/supportcenter/TheDosandDontsThreadedPlastic.asp

Interesting conclusions.

I noticed a LOT of my threaded fittings are gray (schedule 80?)
and most of the glued "end" fittings (near the pumps & valves)
are gray thicker stuff (schedule 200?).

Asking at a pool store, they said they use gray fittings
near the pump "because they handle heat better".

Yet, that article says both teflon tape and schedule 80 fittings
are a no no.

Interesting though the schedule 40 PVC tensile strength of 7K psi
and the PVC thread "resistance" of 400K PSI.

For 2" pipe, apparently each turn past finger tight adds 0.00239
inches per inch, times that 400K psi, nets almost a thousand psi
per turn (956 psi per turn).

The chart gives us only about 4,000 PSI as the maximum allowable
(3912 psi); so it seems that 4 turns past finger tight is the
maximum one can go with schedule 40 PVC.

In summary, that article recommends, for my 2" PVC plumbing:
1. Pipe dope (not teflon tape).
2. Two turns after finger tight (never more than 4).
3. Only schedule 40 plastic (no schedule 80).

It was also interesting that a single threaded fitting reduces
the strength of the system by half the original strength!

[Danny D]

On Sat, 11 May 2013 06:50:06 -0700, tra...@optonline.net wrote:

> Also, the part about Sched 80 vs 40 was interesting. Particularly
> the part about how any threaded PVC joint reduced the overall
> pressure rating by 50% compared to all glued connections.

+1

[hrho...@sbcglobal.net]

On May 11, 9:51 am, Danny D <Dan...@example.com> wrote:

> On Sat, 11 May 2013 06:50:06 -0700, trad...@optonline.net wrote:
> > Also, the part about Sched 80 vs 40 was interesting.  Particularly
> > the part about how any threaded PVC joint reduced the overall
> > pressure rating by 50% compared to all glued connections.
>
> +1

The whole treatise was very informative, I'm sending the web address
to several DIY'ers I know.

[dpb]

While basically true there are some fallacies there, particularly wrt to
the Sch 80 vs Sch 40 discussion on stresses.

The stress on a Sch 80 fitting is _not_ the same as that for a Sch 40
fitting--the extra thickness _DOES_ make a difference because the
remaining cross-sectional area remaining after the threads are cut is
thicker and that increases the denominator (the per sq in portion of the
stress which has units of psi).

I've not gone and looked up actual dimensions, but the percentage
increase in remaining thickness will be quite significant.

--

[Harry K]

On May 11, 7:50 am, Danny D <Dan...@example.com> wrote:
> On Sat, 11 May 2013 08:22:29 -0500, Vic Smith wrote:
> > According to this, tape is a no-no

> >http://www.lascofittings.com/supportcenter/TheDosandDontsThreadedPlas...

>
> Interesting conclusions.
>
> I noticed a LOT of my threaded fittings are gray (schedule 80?)
> and most of the glued "end" fittings (near the pumps & valves)
> are gray thicker stuff (schedule 200?).
>
> Asking at a pool store, they said they use gray fittings
> near the pump "because they handle heat better".
>
> Yet, that article says both teflon tape and schedule 80 fittings
> are a no no.
>
> Interesting though the schedule 40 PVC tensile strength of 7K psi
> and the PVC thread "resistance" of 400K PSI.
>
> For 2" pipe, apparently each turn past finger tight adds 0.00239
> inches per inch, times that 400K psi, nets almost a thousand psi
> per turn (956 psi per turn).
>
> The chart gives us only about 4,000 PSI as the maximum allowable
> (3912 psi); so it seems that 4 turns past finger tight is the
> maximum one can go with schedule 40 PVC.
>
> In summary, that article recommends, for my 2" PVC plumbing:
> 1. Pipe dope (not teflon tape).
> 2. Two turns after finger tight (never more than 4).
> 3. Only schedule 40 plastic (no schedule 80).
>
> It was also interesting that a single threaded fitting reduces
> the strength of the system by half the original strength!

I saw no place that says "no chedule 80". It says DO NOT MIX 40 and
80 schedule.

Harry K

[Oren]

On Sat, 11 May 2013 04:30:52 +0000 (UTC), Danny D <Dan...@example.com>
wrote:

>Q: Does the order of the tape & pipe sealant matter?
>

It matters most about when and where it is applied, which application
is called for - one or the other - not both on the same fitting.

>Starting with this:
> http://www2.picturepush.com/photo/a/12901000/img/12901000.jpg
>

Use sealant. I mentioned before about the type for pool pipes.

>Just wondering, if, for critical 2" PVC applications such as
>pool equipment, when using *both* pipe sealant & teflon tape:
> http://www5.picturepush.com/photo/a/12900978/img/12900978.jpg
>

Are those for PVC pipe?

>Does it matter if we put the teflon tape first:
> http://www3.picturepush.com/photo/a/12901031/img/12901031.jpg
>
>And then the pipe sealant?
> http://www1.picturepush.com/photo/a/12901034/img/12901034.jpg
>

Is that applied over the tape? What a hoot.

>Before screwing the fitting into the housing:
> http://www5.picturepush.com/photo/a/12901038/img/12901038.jpg
>

Aw heck Danny, put a second coat on there <HOOT>

>Just curious:
>Q: Does the order of the tape & pipe sealant matter?

Not much matters after 4-5 good coats of each.

You outdone yourself this time

[DD_BobK]

A lot incorrect information.....

1) Teflon is primarily a lubricant << it is material to seal the
naturally occurring / designed in clearance between internal &
external pipe threads.


2) NPT fittings change their pitch so that the connected pieces deform
the pipe threads more and more making the seal. <<<< incorrect for
ubiquitous / normally used / everyday NPT threads. :(

NPT pipe threads do NOT have interference thread forms, they do not
change pitch.
If they deformed, how could new fittings be used on old pipe?

"Dry fit" pipe threads do exist & do seal based on interference but
they are seldom encountered in daily life.
I used them ~30 year on military hydraulic systems where dope & tape
were prohibited. Dry seal threads are a bitch to use, they sucked...
a major PITA. Be thankful that everyday threads are not as you
describe.

Take a look at the wikipedia article on pipe threads.

cheers
Bob

[DD_BobK]

> According to this, tape is a no-nohttp://www.lascofittings.com/supportcenter/TheDosandDontsThreadedPlas....

Bingo!

Vic has posted an article that would have been my next comment....

The use of tape can lead to splitting of the female threaded fitting.

Loctite makes a product specifically aimed at plastic threads..

No-More-Leaks

As T4 points out, the article notes that threaded joints reduce
pressure capacity by 50% (due to wall thickness reduction).
A side note...in steel piping threading also greatly reduces corrosion
life and that's why we see corrosion evidnence and leaks at the
threaded joints. :(

Specifically, the article's comments about sch 40 vs 80 were related
to the behavior of threaded fittings.

SInce the threaded behavior & subsequent resulting stress is driven by
the wedging action....
a thicker fitting will be just as stressed (to the first order
approximation) as the thinner sch 40 fitting.
Both are "wedged" open to the same extent when tightened the same
number of turns .

The articles's comment was to emphasize that a thicker fitting is not
the answer.... proper sealant (not tape) is the answer.

cheers
Bob

[Danny D]

On Sat, 11 May 2013 11:44:48 -0700, Oren wrote:

> You outdone yourself this time

I'm actually surprised that I apparently put too much on,
according to your comments.

I thought that's how much you're supposed to use.

[DD_BobK]

On May 11, 9:03 am, dpb <n...@non.net> wrote:

+2

[DD_BobK]

+1 Good point...

I agree, it didn't say "no sch 80" ..... it said going to sch 80 &
expecting that to avoid a splitting problem was wrong.

Sch 80 will give you higher system pressure & better resistance to
misc mechanical loads
but it won't solve the tape or over tightening problem. :(

cheers
Bob

[DD_BobK]

On May 11, 9:03 am, dpb <n...@non.net> wrote:

dpb-

I was wondering if they were only looking at stress induced from
tightening
& doing their tightening stress approximation as merely an E * radial
strain based wedging action?
Would that not be independent of wall thickness?

Total fitting load is tightening load + pressure load.

Of course the system pressure capacity would be higher with Sch 80 vs
sch 40
but perhaps they were trying to emphasize the point that sch 80 was
not more over-tightening resistant than sch 40?

Am I missing something here?

cheers
Bob

[dpb]

On 5/11/2013 2:17 PM, DD_BobK wrote:
...

> I was wondering if they were only looking at stress induced from
> tightening & doing their tightening stress approximation as merely an
> E * radial strain based wedging action? Would that not be independent
> of wall thickness?

The _loading_ is same because the dimensions are the same but the stress
is per unit area and there's more material so the actual stress is lower.

Meself, I think they just blew it on that part...

The weakest link in a Sch 40 threaded joint w/ a Sch 80 fitting will
still be the section of threaded Sch 40 not inside the fitting (think of
a female coupling/tee, say, w/ a male pipe for example).

Certainly it is true one doesn't want to over-torque a plastic fitting,
particularly the female that is in tension but it certainly is not true
that the same stress at the same thread depth on a Sch 80 has the same
stress as a Sch 40 because it does have that extra thickness.

--

[Oren]

On Sat, 11 May 2013 19:04:51 +0000 (UTC), Danny D <Dan...@example.com>
wrote:

You never said if the pipe dope was on over the Teflon. It sure
appeared that way or my inference from the photos. More is not always
better.

Again. Is the sealant you used intended for PVC pool pipe fittings?

[dpb]

On 5/11/2013 2:32 PM, dpb wrote:
...

Being as the following was my posting I'll edit it a little in place...

> Certainly it is true one doesn't want to over-torque a plastic fitting,

> particularly [since] the female is in tension but it certainly is not true
> that the stress at the same thread depth on a Sch 80 has the same

> stress as a Sch 40 because it does have that extra thickness.

The above previously wasn't written very well, unfortunately. I recast
it some while writing and didn't get all the edits that could intended
done, sorry. I made a couple of minor fixes above that at least help
but I'll not worry about it further...

I'll just add that loading-->force; stress--> force/unit area. The
geometry (hence tightening) controls loading of this portion of the
total load; they're correct there. But loading isn't the same thing as
stress; it's only the numerator.

--

[Robert]

On May 11, 7:54 am, "Stormin Mormon" <cayoung61**NOJUN...@hotmail.com>
wrote:

> Actually, I do both. Tape, dope, belt,
> suspenders. For real.
> .
> Christopher A. Young

When I put pipe dope on my suspenders, they never
leak.....

[nestork]

DD_BobK;3060537 Wrote:
>
> I was wondering if they were only looking at stress induced from
> tightening & doing their tightening stress approximation as merely an E
> * radial
> strain based wedging action?
> Would that not be independent of wall thickness?
>
> Total fitting load is tightening load + pressure load.
>
> Of course the system pressure capacity would be higher with Sch 80 vs
> sch 40 but perhaps they were trying to emphasize the point that sch 80
> was
> not more over-tightening resistant than sch 40?
>
> Am I missing something here?
>

> Bob


They're just saying that using Schedule 80 fittings is treating the
symptom, not the disease. They're saying that the disease of plastic
female threaded fittings splitting when tightened can be cured by using
a proper thread sealant instead of using pipe dope or teflon tape on
plastic threads.

They're saying that the use of either teflon tape or pipe dope on
plastic threaded fittings will increase the wedging action of the male
pipe threads, thereby increasing the liklihood that the female fitting
will split.

So, the admonition against switching to Schedule 80 female threaded
fittings is that it's not addressing the real problem. If people used a
thread sealant instead of pipe dope or teflon tape, there wouldn't be
the increased splitting force on the female fitting, and there wouldn't
be any splitting problem. So, switching to Schedule 80 female plastic
fittings to avoid splitting is not really solving the problem. The real
solution is found in using thread sealant instead of pipe dope and/or
teflon tape to avoid the splitting problem altogether, rather than buy
stronger fittings that will stand up to the greater splitting force.

Basically, if the square peg won't go into the round hole, you need to
realize that you need a round peg, not a bigger hammer. In this case,
the analogy is that if your female plastic fittings are splitting, you
need to realize that the cause is the pipe dope or teflon tape your
using, and you need to use thread sealant instead, not use a stronger
female fitting.




--
nestork

[dpb]

On 5/11/2013 4:37 PM, nestork wrote:
>
> DD_BobK;3060537 Wrote:
>>
>> I was wondering if they were only looking at stress induced from

>> tightening& doing their tightening stress approximation as merely an E

or they're being over-torqued if not using tape or metal pipe dope.

That's a better summary of the point they're trying to make than
theirs... :)

Now granted the _strain_ is the same as it's the dimensionless ratio of
the distance moved/turn and the geometry of a Sch 40 or Sch 60 or 80
fitting is the same so the geometries do cancel out. But the _stress_
in psi induced by that same strain is less for the fitting with more
material in it--if that weren't so it wouldn't be possible to design for
higher pressures by adding material because it wouldn't matter is the
conclusion that statement leads to. That clearly just isn't so so
they've confused the writeup in that regard.

Granted the weak point is as they state w/ the notching effect of the
threading but there's still significantly more material left behind in a
heavier fitting than the lighter and that does make a difference.

Certainly it shouldn't be/isn't necessary to use heavier fittings if
properly assembled (or the matching fittings are under-designed) is
their main point and that anything that actually causes deformation of
the fitting is detrimental. Those are certainly common sense
conclusions as well.

--

[Vic Smith]

On Sat, 11 May 2013 12:04:13 -0700 (PDT), DD_BobK <rkaz...@gmail.com>
wrote:

>
>The use of tape can lead to splitting of the female threaded fitting.
>

I've never done plastic plumbing except some glued PVC long ago, but
have dealt some with plastic threaded fittings.
Besides the stress on the female, the threads themselves are much more
easily deformed than galvanized. IOW, strippable. It's too easy to
wrap too much tape on plastic, so my first thought was to just use a
dope that can squeeze out, and relieve stress, Didn't know about
"sealers," but if I worked with plastic I'd find out what to use for
the particular plastic. Trickier than galvanized really, which I've
done a lot of.
There's always some danger listening to "old-timer" advice if they
aren't current on "technology."
I'm a long-time fisherman - like my dad's entire family - and it
wasn't until I started reading fishing magazines that I found out
about the improved clinch knot and started using it.
Told my dad it had something like double the strength of the simple
double overhand knot he used and I had used. He ignored me of course.
Then one time we were fishing in Ontario, and he hooked a big
Northern. Line broke when we almost had it landed.
I showed him the curl at the end of his line where it had broke at the
knot. He used the improved clinch after that.
Now I understand there's something better than the improved clinch
knot. Six-turn San Diego jam.
I'll have to check that out. Sounds interesting.

[cl...@snyder.on.ca]

On Sat, 11 May 2013 10:22:27 -0700 (PDT), Harry K <tur...@q.com>
wrote:

So with Sched 40 pipe, no Sched 80 fittings.right??

[Stormin Mormon]

When I wrap myself in teflon tape, I slide off the chair and under the table.

.
Christopher A. Young
Learn more about Jesus
www.lds.org
.
.

"Robert" <jungl...@hotmail.com> wrote in message news:17c84b18-c7cc-440b...@a8g2000yqp.googlegroups.com...

[dpb]

On 5/11/2013 7:49 PM, cl...@snyder.on.ca wrote:
> On Sat, 11 May 2013 10:22:27 -0700 (PDT), Harry K<tur...@q.com>
> wrote:

...

>> I saw no place that says "no chedule 80". It says DO NOT MIX 40 and
>> 80 schedule.

...

Well, that's not QUITE what it says...it says Sch 80 isn't be needed on
Sch 40 properly installed...Sch 80 is overkill but can't really hurt
anything.

> So with Sched 40 pipe, no Sched 80 fittings.right??

Can't hurt unless again they're severely over-torqued...

What it's really trying to say is that Sch 40 fittings
_properly_installed_ are all that a Sch 40 system needs to meet the
pressure requirements that Sch 40 is rated to hold. (Which, of course,
only makes sense else't a component would be underdesigned in comparison
with the rest of the same components.)

What they're driving at is as the other responder said above is that the
correct solution to splitting Sch 40 fittings isn't to go to Sch 60 or
Sch 80 and get by w/ over-tightening them but to install Sch 40
correctly instead.

--

[Harry K]

I learned _my_ lessong on changing from iron to PVC in the middle of
January with a foot of snow on the ground. I had used a male iron-to-
pvc female. That was out in the middle of a pasture and ovf course
there were no shutoffs on the line anywhere. Future runs I made all
_started_ with a shutoff and 'male irong-female PVC fittings were
banned. :)

Harry K

[dimple...@keyboard.com]

On Sat, 11 May 2013 08:46:16 -0400, Ed Pawlowski <e...@snet.net> wrote:

>Joint compound can get hard.

I can get hard too!!!! (even without Viagra)....

[Danny D]

On Sat, 11 May 2013 23:37:04 +0200, nestork wrote:

> If people used a
> thread sealant instead of pipe dope or teflon tape, there wouldn't be
> the increased splitting force on the female fitting

Your summary was fantastically well written and easy to follow!
(much easier than the original article)

It's clear I should not be using Teflon tape.

But which of the non-lubricating "sealants" should I be using then?
http://www5.picturepush.com/photo/a/12900978/img/12900978.jpg

[Danny D]

On Sat, 11 May 2013 11:44:48 -0700, Oren wrote:

> http://www5.picturepush.com/photo/a/12900978/img/12900978.jpg
> Are those for PVC pipe?

While I was in Home Depot, I had called the rectorseal.com 800 number,
and asked what I should use in pool plumbing (800-231-3345).

The guy that answered for technical support didn't really sound all
that knowledgeable, but, he must have known more than I.

He's the one who suggested the red tube you see in the photo.

However, after reading Vic Smith's article, I understand that I don't
want something that lubricates.

I just want sealant.

So, I think *all* the solutions in that picture are wrong.

[Danny D]

On Sat, 11 May 2013 12:34:33 -0700, Oren wrote:

> Again. Is the sealant you used intended for PVC pool pipe fittings?

I called RectorSeal while I was at Home Depot and they said to use
the red tube that I bought (and not the red jar, which was for metals).

The red tube says it's for "plastics", so that's what I used over the
Teflon tape.

Now I understand, from Vic Smith's article, that Teflon tape is a no-no;
and I understand that *lubrication* is a no no ... so it appears *all*
the tubes of sealant I bought from Home Depot are wrong.
http://www5.picturepush.com/photo/a/12900978/img/12900978.jpg

I wonder if the local plumbing and irrigation supply places know this
stuff?

[nestork]

Danny D:

No, the way I read that Lasco article, you should not be using EITHER
pipe dope OR teflon tape on plastic pipe threads.

You should be using a thread sealant meant for plastic threads ONLY.
The Lasco article really should come out and say that pipe dope is not
the same thing as thread sealant meant for plastic threads. It dances
around that point by saying that pipe dope hardens whereas thread
sealant for plastic pipe threads doesn't, thereby allowing it to be
pushed into leakage paths by the water pressure inside the pipe, thereby
blocking that leakage path. It also says that pipe dope and teflon make
the threads slippery, thereby reducing friction and causing
overtightening, whereas a thread sealant meant for plastic threads won't
do that.

Putting the thread sealant on the male threads, then wrapping them with
teflon tape is just as bad as using teflon tape only. The thickness of
the teflon tape you put on is going to increase the spreading force on
the female fitting making it more likely to split.

From my reading of that Lasco article, you should apply thread sealant
meant for plastic threads to your male plastic threads only, and then
screw on the female plastic thread. Tighten to finger tight and then no
more than two full turns after that.

If you've already used teflon tape on your threaded plastic joints, and
there's no splitting or leaking, I would just leave them as is. But, in
future, just use the red bottle that says it's meant for plastic and
nothing else.

I think everyone in here understands the principle of tapered threads,
and that the idea behind teflon tape or pipe dope is that these
materials get compressed between the make and female threads to seal the
joint against leakage. That Lasco article said that metal threads can
gall at metal-to-metal contact points, and that the use of teflon tape
or pipe dope helps to prevent that. In the case of a smooth
plastic-to-plastic thread contact, there's no risk of galling so you
don't need anything as thick as pipe dope or teflon tape to keep the
metals separated until the joint is fully tightened. With plastic
theads, all that's needed to seal the tightened joint is a fluid that's
viscous enough not to be pushed out of the joint by the water pressure
inside the pipe. I'm thinking that plastic fittings can be molded to
much better tolerances than iron pipe can be machined (because the
cutting tool wears down for one thing), so a fluid that's fairly thin
may still be viscous enough to not be pushed out of a small enough
crevice in a threaded joint. Or, at least, at the lower water pressures
that plastic piping is suitable for. So, even if this thread sealant
you bought for plastic piping seems to be too thin compared to pipe
dope, I would still use it by itself, which is what Lasko is telling you
to do.




--
nestork

[HeyBub]

Likewise, look at the article on thread sealing tape:

"One of the defining characteristics of PTFE (Teflon) is how good it is at
defeating friction. The use of PTFE tape in tapered pipe threads performs a
lubricating function, which more easily allows the threads to be screwed
together, to the point of deformation, which is what creates the seal."

[tra...@optonline.net]

All I can tell you is that there are a hell of a lot of people using
teflon tape and not having problems. I think the Lasco
article makes sense and a thread sealant is probably
better. But in the grand scheme of things, I'm not sure
it makes a huge difference. To get the high pressure to
crack a fitting, you'd probably have to over tighten the
fitting. If you know what you're doing, that isn't likely to
happen.

Here's a source that says sealant is preferred, but if
you have to, you can use tape:


http://www.spearsmfg.com/how_to/FG-3B-0105_0706_English.pdf

[Oren]

On Sun, 12 May 2013 04:36:17 +0000 (UTC), Danny D <Dan...@example.com>
wrote:

The T plus 2 looks like it will work:

"RectorSeal T Plus 2 pipe thread sealant is a non-setting,
multi-purpose compound which contains PTFE, plus synthetic fibers to
create a stronger seal. Recommended for use on threaded galvanized
steel, iron, brass, copper, aluminum, stainless steel, polyethylene,
fiberglass reinforced, PVC, CPVC, and ABS pipe. T Plus 2 may be
pressurized immediately following application. Conforms to TT-S-1732."

The RectorSeal TRU-BLU I mentioned will also work:

"RectorSeal� Tru-Blu� pipe thread sealant with PTFE is a fast-dry,
flexible set thread sealant designed for high vibration environments
such as refrigeration and industrial applications. PTFE has been added
to enhance thread lubrication during assembly and break out.
Recommended for use on threaded galvanized steel, iron, brass, copper,
aluminum, stainless steel, polyethylene, fiberglass reinforced, PVC,
and CPVC pipe. Great for use as a positive lock and seal on threaded
fasteners. Certified to NSF/ANSI 61-G"

Both have some amount of Teflon in them.

Isn't the No.5 for metal pipe thread?

[Oren]

On Sun, 12 May 2013 04:49:41 +0000 (UTC), Danny D <Dan...@example.com>
wrote:

>Now I understand, from Vic Smith's article, that Teflon tape is a no-no;
>and I understand that *lubrication* is a no no ... so it appears *all*
>the tubes of sealant I bought from Home Depot are wrong.
> http://www5.picturepush.com/photo/a/12900978/img/12900978.jpg

The T plus 2 should work. It is for PVC, does have some Teflon -- BUT!

(also from the LASKO link)

"...A sealing compound must be compatible to plastics. Many brands of
pipe sealant contain oils, solvents or carriers that can damage
plastic. A proper sealant must be certified by the manufacturer to be
harmless to the fitting material and to not contaminate fluid in the
pipe.

Finally, a sealing compound must not lubricate the joint to the point
that over-tightening is encouraged. Several sealants on the market
meet all these requirements."

...
I would trust the T plus 2, just do not over tighten because it does
have some Teflon in it...

[Danny D]

On Sun, 12 May 2013 08:41:40 +0200, nestork wrote:

> Putting the thread sealant on the male threads, then wrapping them with
> teflon tape is just as bad as using teflon tape only.

Actually, I put the Teflon tape on first ... and then put the gooey
stuff on. Now I know that both of those solutions was dead wrong!

In fact, it's extremely hard, it seems, to find the "right stuff"
at the home box stores that meets the three requirements:
a) PVC
b) Non lubricating
c) Sealant

Here is a large-format photo of the tubes of wrong "stuff" I bought:
http://www4.picturepush.com/photo/a/12914627/img/12914627.jpg

* Harvey's TFE Paste, Part No. 023015 *
Front: White slow setting superior quality pipe thread compound *
Rear: Non-hardening, withstands up to 3,000 psi (gases) at temperatures
from -50F to +400F and 10,000 psi (liquids) from -50F to +400F.
Use on water, steam, natural, & LP gas, oils, fuels, & dilute acids.
Apply to clean male pipe threads on metals, PVC, CPVC, ABS,
polypropylene, and nylon.
Lubricates as it seals; will not harm seals of valves or faucets.

* Rectorseal Tplus2 Pipe Thread Sealant, Product Code No. 23710 *
Front: Seals and lubricates threaded connections on metal & plastics.
Formulated for potable water, natural gas and a wide variety of fluids
and gases.
Teeny tiny print: Meets CSA requirements working temperature range
-40F to 125F. Maximum working pressure 125 psi. For use with natural
gas and LP (vapor state only). Use on steel, galvanized steel, iron,
brass, copper, & aluminum. For pipe size up to & including 1 1/4".

[DD_BobK]

Bingo! +2 T plus 2 is the goop to use.

[Danny D]

On Sun, 12 May 2013 05:29:15 -0700, tra...@optonline.net wrote:

> in the grand scheme of things, I'm not sure it makes a huge
> difference.

I don't disagree - and - I'm a big believer in doing it any way
you want - BUT - only after knowing the right way to do it -
and not out of sheer ignorance (which was what I was doing).

Since this is alt.home.repair, I agree we should at least
discuss and know HOW to do it right.

At this point, we know that the correct way to do it is not
with Teflon tape, and certainly not with BOTH tape & sealant.

Also we know that the right way is to use a * non-lubricating *
sealant, which is actually hard to find at the big box stores.

> http://www.spearsmfg.com/how_to/FG-3B-0105_0706_English.pdf

This confirms a few things in the Vic Smith article.
- Teflon tape is deprecated
- Teflon tape is a lubricant
- Never use both Teflon tape and sealant paste
- Tighten 2 to 3 turns past finger tight

It looks like huckleberries are in season, as the "right stuff"
is the "Blue 75 thread sealant". I'll see if Home Depot has the
stuff in stock.

[Danny D]

On Sun, 12 May 2013 07:01:35 -0700, Oren wrote:

> Isn't the No.5 for metal pipe thread?

Yes.
I did not use that RectorSeal No. 5 stuff for my PVC.

In fact, it appears NONE of the "pipe stuff" I own is
correct for PVC; so I will try to find the Spears Blue 75
thread sealant at the irrigation supply places on Monday.
http://www.spearsmfg.com/how_to/FG-3B-0105_0706_English.pdf

And, in the future, if I'm forced to use Teflon tape,
I'll use this method of wrapping the tape properly:
http://www5.picturepush.com/photo/a/12914723/img/12914723.png

[Danny D]

On Sun, 12 May 2013 16:57:56 +0000, Danny D wrote:

> In fact, it appears NONE of the "pipe stuff" I own is
> correct for PVC;

I should correct that slightly, by saying I read and
understood Oren's and DD_BobK's recommendation of the
best being the Tplus2 pipe thread sealant.

The only proscription against that stuff, based on
the Vic Smith article, was the fact it also lubricates
as it seals.

However, if I keep to the finger-tight-plus-two-turns
rule, I should be safe with the Tplus2 stuff.

I'm going to remove all the fittings, and try again.
http://www2.picturepush.com/photo/a/12915445/img/12915445.jpg

[Oren]

On Sun, 12 May 2013 16:17:54 +0000 (UTC), Danny D <Dan...@example.com>
wrote:

>It looks like huckleberries are in season, as the "right stuff"
>is the "Blue 75 thread sealant". I'll see if Home Depot has the
>stuff in stock.

I've been trying to get your attention... Instead of buying new right
now, use the T plus 2 sealant you have on hand. Yes it has Teflon, so
do not over tighten. It is for PVC pipe thread.

I use Teflon tape on PVC irrigation and some other places. I must
have ten partial rolls around here somewhere, if I rounded them up.

I just don not suggest tape on pool pipes, when a sealer is faster,
better at what it does and has no complaints from me.

The link from trader is a good one. Almost says the same as the LASCO
link, but in a different way :-\

[dpb]

On 5/12/2013 12:18 PM, Danny D wrote:
...

> The only proscription against that stuff, based on
> the Vic Smith article, was the fact it also lubricates
> as it seals.
>
> However, if I keep to the finger-tight-plus-two-turns
> rule, I should be safe with the Tplus2 stuff.

...

I typically just use a little permatex blue silicone or the like. Yeah,
it's a little slick but just don't overdo tightening and you're fine.

Another that works fine is a white lithium; same thing as for usage. I
have even just used a little ol' gun grease when other wasn't handy and
it was.

--

[cl...@snyder.on.ca]

On Sun, 12 May 2013 04:49:41 +0000 (UTC), Danny D <Dan...@example.com>
wrote:

Just because the recommended red stuff works as a lubricant doesn't
mean it's not the right stuff. Virtually ANY sealant will "act as" a
lubricant.

[cl...@snyder.on.ca]

On Sun, 12 May 2013 07:00:15 -0500, "HeyBub" <hey...@NOSPAMgmail.com>
wrote:

Just because it is a lubricand doesn't mean it is not also a sealer -
and vise versa. If all you need is a lubricant, just oil the threads
and see how well it seals - or grease the threads. It is a combination
product.

[Larry W]

In article <kmkhhr$bjd$6...@speranza.aioe.org>,
Danny D <Dan...@example.com> wrote:
>Q: Does the order of the tape & pipe sealant matter?
>
>Starting with this:
> http://www2.picturepush.com/photo/a/12901000/img/12901000.jpg
>
>Just wondering, if, for critical 2" PVC applications such as
>pool equipment, when using *both* pipe sealant & teflon tape:
> http://www5.picturepush.com/photo/a/12900978/img/12900978.jpg
>
>Does it matter if we put the teflon tape first:
> http://www3.picturepush.com/photo/a/12901031/img/12901031.jpg
>
>And then the pipe sealant?
> http://www1.picturepush.com/photo/a/12901034/img/12901034.jpg
>
>Before screwing the fitting into the housing:
> http://www5.picturepush.com/photo/a/12901038/img/12901038.jpg
>
>Just curious:
>Q: Does the order of the tape & pipe sealant matter?
>

It doesn't matter what order you apply them in, as long as you apply
the first properly, and NEVER apply the 2nd.


--
Often wrong, never in doubt.

Larry W. - Baltimore Maryland - lwasserm(a)sdf. lonestar. org

[k...@attt.bizz]

You still have to apply the correct one first.

[Vic Smith]

On Sun, 12 May 2013 17:18:09 +0000 (UTC), Danny D <Dan...@example.com>
wrote:

>

>The only proscription against that stuff, based on
>the Vic Smith article, was the fact it also lubricates
>as it seals.
>

Please quit saying that's "my article." I didn't write that, I just
cited it. I have no experience at all with threaded plastic pipe.
And I'm not buying all this emphasis on "lubricate vs non-lubricate."
As long as it's compatible with the plastic, seals the threads, and
doesn't harden up, it should work.
"Overtightening" because threads are lubed makes no sense to me.
One guy's "feel" for tight isn't the same as another's. You use a
different length wrench, the feel changes.
Likewise, these guys are saying stuff like "2 turns past
finger-tight." That fine if there's no burrs on the threads, the
threads are consistently formed, and everybody has the same fingers.
That's not realistic. What's more realistic is a consistent taper and
consistent thread count.
You want to look at how many threads should still be exposed for a
good fit, and tighten to there. lube or no lube. I can see that with
galvanized and know when the male is inserted far enough .
The force used to get there can vary depending on the thread
condition, but threads exposed is the best indication of what force
the taper is putting on the female, and when to stop cranking down.
Anyway, that's how I'd approach tightening plastic too.
But until I did it, it's still a guess to me.

[nestork]

Vic Smith;3061096 Wrote:
>
> "Overtightening" because threads are lubed makes no sense to me.
>

It does to me.

The less force needed to overcome friction, the more force you have
available to tighten the joint. Try slipping a bicycle handle bar grip
onto bare chrome plated handle bars and you'll see what a fight it can
be. Now, lubricate the handle bars so the rubber grip slides over a
thin film of oil, and you'll see what a difference friction makes.

It's like a car. The more power used to drive the power steering pump,
the air conditioning compressor, the water pump and the alternator, the
less power you have left over for turning the wheels.




--
nestork

[Vic Smith]

What does any of this have to do with tapered pipe threads?

[Danny D]

On Sun, 12 May 2013 16:05:09 -0400, clare wrote:

> Just because it is a lubricand doesn't mean it is not also
> a sealer - and vise versa.

I ended up using the 2-in-one lubricant + sealer, after
taking pains to remove all vestiges of the Teflon tape.

BTW, do we lubricate the unions?
http://www3.picturepush.com/photo/a/12918676/img/12918676.jpg

I think they go on dry ... but I also thought Teflon tape was
to be used on the threaded fittings (and that was wrong).

[Danny D]

On Sun, 12 May 2013 19:01:18 -0500, Vic Smith wrote:

> You want to look at how many threads should still be
> exposed for a good fit, and tighten to there.

Here are the exposed threads on what I ended up with on
the schedule 40 fitting:
http://www1.picturepush.com/photo/a/12918709/img/12918709.jpg

And here are the exposed threads on the schedule 80 nipple
(this is the one that I had the Teflon tape + sealant) after
I removed the Teflon tape and sealant due to what I read
in this thread - and started over:
http://www1.picturepush.com/photo/a/12918679/640/12918679.jpg

[Danny D]

On Sun, 12 May 2013 19:27:28 -0400, krw wrote:

>>It doesn't matter what order you apply them in, as long as
>> you apply the first properly, and NEVER apply the 2nd.
>
> You still have to apply the correct one first

UPDATE:

Given the wonderful advice in this thread, I ripped out all the
threaded fittings today, and started over - this time with *just*
the PVC sealant+lubricant (and specifically, *no Teflon tape*).
http://www4.picturepush.com/photo/a/12918677/640/12918677.jpg

On this second pass, I put only a bead of paste on the threads:
http://www5.picturepush.com/photo/a/12918678/640/12918678.jpg

I then tightened the fitting two turns after hand tight:
http://www1.picturepush.com/photo/a/12918679/640/12918679.jpg

I also replaced the schedule 40 fitting by putting the sealer on:
http://www1.picturepush.com/photo/a/12918704/640/12918704.jpg

I wasn't sure how thick the sealant was supposed to go on though:
http://www2.picturepush.com/photo/a/12918705/640/12918705.jpg

As instructed, I then screwed the fitting on only hand tight:
http://www4.picturepush.com/photo/a/12918707/640/12918707.jpg

I used a pipe wrench for the last two turns after hand tight:
http://www5.picturepush.com/photo/a/12918708/640/12918708.jpg

With this being the end result:
http://www1.picturepush.com/photo/a/12918709/640/12918709.jpg

[cl...@snyder.on.ca]

On Mon, 13 May 2013 02:57:23 +0200, nestork
<nestork...@diybanter.com> wrote:

>

Except if you follow instructions and tighten the specified 1.5?
turns after contact it doesn't matter how much or how little friction
there is in the joint. the specified number of turns after contact
will ALWAYS give the same fit - and the same amount of thread
deformation or fitting swell.

[DD_BobK]

HB-

Please provide sight / link for following.....

""One of the defining characteristics of PTFE (Teflon) is how good it
is at
defeating friction. The use of PTFE tape in tapered pipe threads
performs a
lubricating function, which more easily allows the threads to be
screwed
together, to the point of deformation, which is what creates the
seal."

>>>to the point of deformation<<<

I assume you mean deformation of the threads? & not the tape?

Internal & external threads of NPT threads type do not interfere with
each other.
Take a look in Machinery's Handbook to get an idea of the design of
NPT threads.
There is a designed in & manufactured in clearance between the crests
& the valleys..
thus creating a spiral leak path that needs a sealant not a lube.

cheers
Bob

[DD_BobK]

Excellent point. OP needs to apply a bit of common sense & stop
looking for the holy grail.

cheers
Bob

[DD_BobK]

I should add to be clear....

NPT threads need a sealant to seal the spiral leak path.
NPT threads do not seal by thread deformation.

Hint: To do a practical proof of want I knew to be the design intent
of NPT threads,
I did the lube alone assembly of NPT pipe & fittings.... they leak no
matter how tight. :(
I used oil so that no "sealant" was present. :)

cheers
Bob

[Caryn]

On Mon, 13 May 2013 04:43:10 -0700, DD_BobK wrote:

> NPT threads need a sealant to seal the spiral leak path.
> NPT threads do not seal by thread deformation.

Are the union threads NPT also?

[tra...@optonline.net]

You can put some silicone lube on the rubber o-ring. That is
what seals it. Nothing goes on the threads.

[tra...@optonline.net]

On May 12, 8:01 pm, Vic Smith <thismailautodele...@comcast.net> wrote:
> On Sun, 12 May 2013 17:18:09 +0000 (UTC), Danny D <Dan...@example.com>
> wrote:
>
>
>
> >The only proscription against that stuff, based on
> >the Vic Smith article, was the fact it also lubricates
> >as it seals.
>
> Please quit saying that's "my article."  I didn't write that, I just
> cited it.

I think we all understood that's what he meant.

 I have no experience at all with threaded plastic pipe.
> And I'm not buying all this emphasis on "lubricate vs non-lubricate."
> As long as it's compatible with the plastic, seals the threads, and
> doesn't harden up, it should work.

I agree. For that matter, Teflon tape is widely used and if it
made a huge difference, there would be leaking fittings everywhere.
Yet, lots of people, including many pros are using tape.

> "Overtightening" because threads are lubed makes no sense to me.

Imagine pushing a v shaped wedge into a v cut opening
in a piece of plastic or metal. The further in the wedge goes,
the more splitting force you have. Do you think with the same
amount of force applied to the wedge, it will go in further with
or without lube?

> One guy's "feel" for tight isn't the same as another's.  You use a
> different length wrench, the feel changes.

Agree. That's where experience counts. And why perhaps
those with little experience could wind up in trouble using
Teflon tape while others have used it and it's worked fine.

> Likewise, these guys are saying stuff like "2 turns past
> finger-tight."  That fine if there's no burrs on the threads, the
> threads are consistently formed, and everybody has the same fingers.
> That's not realistic.  What's more realistic is a consistent taper and
> consistent thread count.
> You want to look at how many threads should still be exposed for a
> good fit, and tighten to there. lube or no lube.  I can see that with
> galvanized and know when the male is inserted far enough .
> The force used to get there can vary depending on the thread
> condition, but threads exposed is the best indication of what force
> the taper is putting on the female, and when to stop cranking down.

And there I disagree. Joints are tight when they are tight.
If you try to rely on looking at how many threads are showing,
I think you're in for trouble. How do you even know that the
number of threads is consistent from one pipe to another?
For example, if you get a piece of pipe cut and threaded at
HD, is piece A going to have exactly the same number of threads
as piece B? You just have to develop a feel for it and learn
from experience.

[tra...@optonline.net]

I would be using channel lock pliers, not a big honking pipe wrench.
No need for anywhere the amount of force you can get with that
wrench. And by using pliers, you have a better feel for the force
being applied, less likely to overtighten, etc. Plus it's easier to
handle too.

[Danny D]

On Mon, 13 May 2013 06:09:12 -0700, tra...@optonline.net wrote:

> I agree. For that matter, Teflon tape is widely used and if it made a
> huge difference, there would be leaking fittings everywhere.
> Yet, lots of people, including many pros are using tape.

I should also note that the original fittings certainly had
Teflon tape on them, presumably from the professional installers.

I did have leaks in the two inlets to the pool pumps though; but
who knows why (hopefully they're fixed with the new fittings).

[Danny D]

On Mon, 13 May 2013 06:13:51 -0700, tra...@optonline.net wrote:

> I would be using channel lock pliers, not a big honking pipe wrench.

I didn't know what people use!

Thanks for that advice.

[Oren]

On Mon, 13 May 2013 01:46:56 +0000 (UTC), Danny D <Dan...@example.com>
wrote:

>

>BTW, do we lubricate the unions?
> http://www3.picturepush.com/photo/a/12918676/img/12918676.jpg

No. Just the O-ring (pool silicone lube). Make sure the union mates
properly and the O-ring seals as needed.

And example is your union on the filter you removed. Nothing on the
threads.

[k...@attt.bizz]

On Mon, 13 May 2013 06:13:51 -0700 (PDT), "tra...@optonline.net"
<tra...@optonline.net> wrote:

>On May 12, 10:26锟絧m, Danny D <Dan...@example.com> wrote:
>> On Sun, 12 May 2013 19:27:28 -0400, krw wrote:
>> >>It doesn't matter what order you apply them in, as long as
>> >> you apply the first properly, and NEVER apply the 2nd.
>>
>> > You still have to apply the correct one first
>>
>> UPDATE:
>>
>> Given the wonderful advice in this thread, I ripped out all the
>> threaded fittings today, and started over - this time with *just*
>> the PVC sealant+lubricant (and specifically, *no Teflon tape*).

>> 锟絟ttp://www4.picturepush.com/photo/a/12918677/640/12918677.jpg

>>
>> On this second pass, I put only a bead of paste on the threads:

>> 锟絟ttp://www5.picturepush.com/photo/a/12918678/640/12918678.jpg

>>
>> I then tightened the fitting two turns after hand tight:

>> 锟絟ttp://www1.picturepush.com/photo/a/12918679/640/12918679.jpg

>>
>> I also replaced the schedule 40 fitting by putting the sealer on:

>> 锟絟ttp://www1.picturepush.com/photo/a/12918704/640/12918704.jpg

>>
>> I wasn't sure how thick the sealant was supposed to go on though:

>> 锟絟ttp://www2.picturepush.com/photo/a/12918705/640/12918705.jpg

>>
>> As instructed, I then screwed the fitting on only hand tight:

>> 锟絟ttp://www4.picturepush.com/photo/a/12918707/640/12918707.jpg

>>
>> I used a pipe wrench for the last two turns after hand tight:

>> 锟絟ttp://www5.picturepush.com/photo/a/12918708/640/12918708.jpg

>>
>> With this being the end result:

>> 锟絟ttp://www1.picturepush.com/photo/a/12918709/640/12918709.jpg

>
>I would be using channel lock pliers, not a big honking pipe wrench.
>No need for anywhere the amount of force you can get with that
>wrench. And by using pliers, you have a better feel for the force
>being applied, less likely to overtighten, etc. Plus it's easier to
>handle too.

Pipe wrenches have the wrong jaws, too. They're curved, have a moving
jaw, and have teeth, all of which are designed to bite into a round
pipe. None of which is required for unions and certainly isn't wanted
for PVC.

[Oren]

On Mon, 13 May 2013 02:26:13 +0000 (UTC), Danny D <Dan...@example.com>
wrote:
>

>On this second pass, I put only a bead of paste on the threads:
> http://www5.picturepush.com/photo/a/12918678/640/12918678.jpg
>

Can you just be bit more sloppier, not enough on the pipe. <G>

>
>I wasn't sure how thick the sealant was supposed to go on though:
> http://www2.picturepush.com/photo/a/12918705/640/12918705.jpg
>

Almost perfect, but not sloppy enough.

>
>I used a pipe wrench for the last two turns after hand tight:
> http://www5.picturepush.com/photo/a/12918708/640/12918708.jpg
>

LMAO

[nestork]

'Caryn[_2_ Wrote:
> ;3061321']

> Are the union threads NPT also?
>

Caryn:

"NPT" means "National Pipe Thread", and NPT threads are a tapered
thread, like this:

[image: http://www.plumbingsupply.com/images/npt-thread-taper.jpg]

A waterproof seal is achieved by some soft material (like teflon tape or
pipe dope) being compressed between the male and female threads as the
joint is tightened.

Other threads, like the threads on a bolt or a light bulb are not
tapered:

[image: http://www.instockfasteners.com/IMAGE/BM_81307000H__21.jpg]

In plumbing, you can tell which threads to put teflon tape, pipe dope or
thread sealer on by just asking yourself the question: "In this
connection, is the water tight seal made by the threads themselves?" If
so, then you need pipe dope, teflon tape or thread sealer on those
threads. If not, then you shouldn't put anything at all on those
threads.

So, in the case of the union shown here:

[image: http://www.hartindustries.com/images/threadedunions150.jpg]

The two threads where pipes screw in at each END of the union are NPT
threads and would need pipe dope, teflon tape or thread sealant on them
because it's the threads themselves that make the water proof seal at
those joints.

However, the coarser thread on the collar of the union is not a tapered
NPT thread and doesn't need pipe dope, teflon tape or thread sealant on
it because it doesn't make a water proof seal. The water leakage path
through those collar threads is prevented by the O-ring shown inside
that union (as seen in the picture). It's that O-ring that prevents
water leakage through the collar threads, not the threads on the collar
wedging themselves together as the joint is tightened like NPT threads
do.

So, with the above union, you would put pipe dope, teflon tape or thread
sealant when screwing the union onto the pipes it's meant to connect.
But, you wouldn't put anything on the collar threads when connecting the
two halves of the union together. The teflon tape, pipe dope or thread
sealant would prevent leakage through the pipe threads, and the O-ring
prevents leakage though the collar threads.

Hope this helps.




--
nestork

[Oren]

On Mon, 13 May 2013 13:19:23 +0000 (UTC), Danny D <Dan...@example.com>
wrote:

>On Mon, 13 May 2013 06:09:12 -0700, tra...@optonline.net wrote:
>
>> I agree. For that matter, Teflon tape is widely used and if it made a
>> huge difference, there would be leaking fittings everywhere.
>> Yet, lots of people, including many pros are using tape.
>
>I should also note that the original fittings certainly had
>Teflon tape on them, presumably from the professional installers.
>

If you look back to the photo of when you removed the strainer fitting
with the tape, the tape did not extend the length of the threads. It
was applied incorrectly from the start. A PVC sealant should have been
used instead of tape (IMO).

[DD_BobK]

On May 13, 6:19 am, Danny D <Dan...@example.com> wrote:

" professional installers" ??? yeah, right!
from the layout, they look like hacks

[tra...@optonline.net]

+++++1

[Danny D]

On Mon, 13 May 2013 09:09:37 -0700, Oren wrote:

> Can you just be bit more sloppier, not enough on the pipe. <G>

Part of the problem is taking pictures without getting
the goop on the camera, so I tried to use only one hand
for putting on the goop while the other hand held the camera ...

:)

[Oren]

On Mon, 13 May 2013 19:05:47 +0000 (UTC), Danny D <Dan...@example.com>
wrote:

That just sounds nasty!

[Oren]

On Mon, 13 May 2013 10:51:04 -0700 (PDT), "tra...@optonline.net"
<tra...@optonline.net> wrote:

>> " professional installers" �??? yeah, right!
>> from the layout, they look like hacks
>
>+++++1

I wager a hazard, that the pool cost around 200G new.

[nestork]

Danny D:

From what I can see, you're putting on way too much sealer on those
threads. I don't think it will do any harm, but unless you're catching
what comes dripping out of that joint as you tighten it, then you're
just wasting the stuff.

I would put a much lighter coat of thread sealant on your male threads.

And, of course, I'd try to be sloppy about it.




--
nestork

[DD_BobK]

On May 13, 12:51 pm, Oren <O...@127.0.0.1> wrote:
> On Mon, 13 May 2013 10:51:04 -0700 (PDT), "trad...@optonline.net"

>
> <trad...@optonline.net> wrote:
> >> " professional installers" ??? yeah, right!
> >> from the layout, they look like hacks
>
> >+++++1
>
> I wager a hazard, that the pool cost around 200G new.

Depends on when it was built but with that hidden cover storage &
automatic cover.... 200k ain't far off.

[DD_BobK]

On May 13, 6:09 am, "trad...@optonline.net" <trad...@optonline.net>
wrote:

Actually, two things work in our favor.... threading machines have
automatic stops & molded parts are consistent (and hopefully the
tooling was "proofed").

Of course there is always some variability of the parts & how much
tape (that's dope is better for plastic) but the number of turns to
"make up" after finger / hand tight is pretty consistent.

Pipe threads have a standardized / designed thread form.....well,
unless they come from China :)

Seriously pipe threads are very consistent unless made by a total hack
shop...which is happening less & less as 3rd world mfrs learn (ie get
parts rejected)

IIRC pipe threads might even have torque limits for "tight
joints"...too lazy to look it up.

cheers
Bob

[Oren]

On Mon, 13 May 2013 20:33:45 -0700 (PDT), DD_BobK <rkaz...@gmail.com>
wrote:

He has those pop up cleaners instead of a sweeper / cleaner. Solar on
the side of a mountain, heating, all equipment is on three different
levels (Mt. side). I recall there are 17 or so Jandy vales and three
single speed pump motors in that git up. 200K would be cheap I think.

For giggles some years back I checked prices for a new pool.
Interesting was that if you want pool 15' long, it would cost the same
as a 28' pool. The say it was the base price for 28', regardless.

Contractors here had to have a separate license to build pools. A
"pool contractor license". State law that reduces contractor run
around, to protect folks.

[Oren]

On Mon, 13 May 2013 22:44:51 +0200, nestork
<nestork...@diybanter.com> wrote:

>I would put a much lighter coat of thread sealant on your male threads.
>
>And, of course, I'd try to be sloppy about it.
>

Well, Bless your heart! A single Canadian with a sense of humor.

[DD_BobK]

deformation of the threads or the tape?

The crests & valleys of internal & external NPT pipe threads NEVER
touch.
Look at the thread form description in Machinery's Handbook.

The spiral leak path ALWAYS exists, this spiral MUST be seal with a
sealing compound.
You can tighten lubricated NPT pipe & fitting joints 'til you run out
of torque ..the joint will leak unless sealant is used.

[DD_BobK]

Missed this...

Are the union threads NPT also?

No, threads on unions are some sort of straight thread.
The purpose of the union thread is to provide a means to compress the
seal; o-ring, brass insert or union material depending on design of
union.