# Why are threads on rigid conduit tapered?



## Rock knocker (Mar 8, 2016)

There are two types of American standard pipe threads NPT and NPSM (National Pipe Tapered and National Pipe Straight Mechanical). NPT is required to make a sealed, tight and vibration free connection whether it is for plumbing, keeping conduit as free as possible from rain or maintaining a ground.


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## RePhase277 (Feb 5, 2008)

Another good reason is because the first threaded conduit was just water pipe. As it evolved separately from water pipe, the thread style was maintained to make new pipe backward compatible with old pipe.


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## MechanicalDVR (Dec 29, 2007)

Rock knocker said:


> There are two types of American standard pipe threads NPT and NPSM (National Pipe Tapered and National Pipe Straight Mechanical). NPT is required to make a sealed, tight and vibration free connection whether it is for plumbing, keeping conduit as free as possible from rain or maintaining a ground.


I think you got it right with keeping the wetness out as well as possible and making a firm connection. The mechanics of it provide more surface area for a ground connection and more grip than just bottoming out the pipe to a connector.


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## Rock knocker (Mar 8, 2016)

RePhase277 said:


> Another good reason is because the first threaded conduit was just water pipe. As it evolved separately from water pipe, the thread style was maintained to make new pipe backward compatible with old pipe.


 If that was the case NPSM would be allowed, and it isn't. NPT and NPSM can be connected, and are therefore backwards compatible


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## 99cents (Aug 20, 2012)

I don't know if this applies but five threads must be engaged in hazardous locations. The theory is that hot gases will cool down before they reach the atmosphere.


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## RePhase277 (Feb 5, 2008)

Rock knocker said:


> If that was the case NPSM would be allowed, and it isn't. NPT and NPSM can be connected, and are therefore backwards compatible


I didn't say it was the only reason. Calm down.


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## bill39 (Sep 4, 2009)

99cents said:


> I don't know if this applies but five threads must be engaged in hazardous locations. The theory is that hot gases will cool down before they reach the atmosphere.


There was a different long thread about this subject and how conduit couplings are different from plumber's couplings. What 99cents said here was mentioned and seemed to make the most sense.


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## drewsserviceco (Aug 1, 2014)

Electrical couplings have straight threads and plumbing couplings are tapered, providing the sealing action. I've never worked on any underground piping of any kind that wasn't full of water. 

To that point, I don't see the NPT requirement having much affect at keeping water out at a coupling, but where it would be most critical is at hubs where the conduit would enter boxes or equipment and those hubs have the tapered threads that would facilitate sealing water out.


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## drewsserviceco (Aug 1, 2014)

RePhase277 said:


> Another good reason is because the first threaded conduit was just water pipe. As it evolved separately from water pipe, the thread style was maintained to make new pipe backward compatible with old pipe.



FWIW: I would think the first electrical pipe was actually gas pipe since it's the gas lighting that was being replaced and I've come upon old fixtures hanging from the old gas piping. Sometimes the wiring was in the pipe and sometimes it was K&T with the piping just supporting the fixture. 

I even found one that there was a cool adapter that went from 1/2" gas pipe to 3/8" for the fixture nipple but instead of a standard reducing coupling, this was also a cap to seal off the gas pipe. I know because I wanted to take the fitting for my "museum" and the gas was still live.


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## Switched (Dec 23, 2012)

drewsserviceco said:


> FWIW: I would think the first electrical pipe was actually gas pipe since it's the gas lighting that was being replaced and I've come upon old fixtures hanging from the old gas piping. Sometimes the wiring was in the pipe and sometimes it was K&T with the piping just supporting the fixture.
> 
> I even found one that there was a cool adapter that went from 1/2" gas pipe to 3/8" for the fixture nipple but instead of a standard reducing coupling, this was also a cap to seal off the gas pipe. I know because I wanted to take the fitting for my "museum" and the gas was still live.


About 12 years ago I ran across a dual purpose gas and electric fixture.... I have no idea if it was a mass manufactured unit or if some guy just was crafty. The HO disconnected the gas and had the fixtures restored to just electric.


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## RePhase277 (Feb 5, 2008)

drewsserviceco said:


> FWIW: I would think the first electrical pipe was actually gas pipe since it's the gas lighting that was being replaced and I've come upon old fixtures hanging from the old gas piping. Sometimes the wiring was in the pipe and sometimes it was K&T with the piping just supporting the fixture.
> 
> I even found one that there was a cool adapter that went from 1/2" gas pipe to 3/8" for the fixture nipple but instead of a standard reducing coupling, this was also a cap to seal off the gas pipe. I know because I wanted to take the fitting for my "museum" and the gas was still live.


Yeah. True dat. Either way, it was originally tapered thread pressurized pipe.


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## lightman (Oct 14, 2015)

drewsserviceco said:


> I've never worked on any underground piping of any kind that wasn't full of water.


This has been my experience as well. I don't think it leaks as much as it sweats. I've put pipe in one day and had water in it the next. No rain, no dew, no precipitation of any kind! 

On a different note, I think you are required to paint field cut threads with zinc paint.


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## drewsserviceco (Aug 1, 2014)

Switched said:


> About 12 years ago I ran across a dual purpose gas and electric fixture.... I have no idea if it was a mass manufactured unit or if some guy just was crafty. The HO disconnected the gas and had the fixtures restored to just electric.



I imagine that it was an enterprising electrician selling the conversion or more likely the local hardware store. The one I saw was originally a gas fixture and it looked like someone cobbled together all the loose parts to electrify it. The lamp cord was tie wired to the arms with 20 awg copper wire and all. 

You couldn't even tell from the ground, only once you were up close. The craftsmanship was impressive, both for the original fixture that had gas going through the brass arms and the subsequent conversion to electric.


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## MechanicalDVR (Dec 29, 2007)

Switched said:


> About 12 years ago I ran across a dual purpose gas and electric fixture.... I have no idea if it was a mass manufactured unit or if some guy just was crafty. The HO disconnected the gas and had the fixtures restored to just electric.


I think you could find those in old Sears Roebuck catalogs if I'm not mistaken.


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## MechanicalDVR (Dec 29, 2007)

RePhase277 said:


> Yeah. True dat. Either way, it was originally tapered thread pressurized pipe.


Cleaning out my Uncle's shop when I was a young kid he gave me a bunch of non ratcheting pipe threaders. 1/8" and 1/4" were straight thread and the larger ones all tapered. At the time he said the smaller ones were for street light work back in the day and I never questioned any further.


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## TGGT (Oct 28, 2012)

They look tapered to me. It's what's helps them get snug in couplings.


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## micromind (Aug 11, 2007)

As noted above, the threads on the pipe are the same for both electrical and plumbing but the couplings are different. 

The plumbing couplings (sometimes called 'banded couplings') exist to make a leak-free joint. 

The electrical couplings (sometimes called 'merchant couplings') exist mainly for physical strength. 

The plumbing couplings don't go all the way the the end of the pipe threads, the electrical ones do. For a good seal, the threads need to 'clamp down' on each other but for strength, they need to go all the way to where the pipe threads are not very deep. The tapered threads allow the electrical coupling to be threaded all the way onto the pipe.


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## Semi-Ret Electrician (Nov 10, 2011)

I've been asking myself the same question for a long time. Why a straight thread on electrical couplings?

Only a few of the conduit threads actually engage the straight coupling, compared to water pipe with 7 or 8 threads.

So, the combination allows water to enter the conduit, a very weak physical connection is formed and, the electrical connection is not nearly as good as a tapered conduit and coupling would be. 

The Nec recognizes these faults because conduit hubs must be tapered.

Why not allow tapered electrical couplings?


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## MechanicalDVR (Dec 29, 2007)

Semi-Ret Electrician said:


> I've been asking myself the same question for a long time. Why a straight thread on electrical couplings?
> 
> Only a few of the conduit threads actually engage the straight coupling, compared to water pipe with 7 or 8 threads.
> 
> ...


Great question that should be addressed by the code writers.


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## micromind (Aug 11, 2007)

Semi-Ret Electrician said:


> I've been asking myself the same question for a long time. Why a straight thread on electrical couplings?
> 
> Only a few of the conduit threads actually engage the straight coupling, compared to water pipe with 7 or 8 threads.
> 
> ...


A tapered coupling would likely not thread all the way onto the pipe, this would reduce the strength of the joint. 

As it is, the coupling threads all the way to where the threads on the pipe are very shallow. Closer to the end, the threads are cut deeper and the joint would be weaker.


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## Semi-Ret Electrician (Nov 10, 2011)

micromind said:


> A tapered coupling would likely not thread all the way onto the pipe, this would reduce the strength of the joint.
> 
> As it is, the coupling threads all the way to where the threads on the pipe are very shallow. Closer to the end, the threads are cut deeper and the joint would be weaker.


On a typical conduit to coupling connection after 1 turn CCW very little torque is required to undo the conduit, not so with water pipe.


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## Rock knocker (Mar 8, 2016)

RePhase277 said:


> I didn't say it was the only reason. Calm down.


Nice, that's called "attack by innuendo". I wasn't wound up or anything of the sort, I just pointed out why your statement was probably incorrect.

I hope you get the help that you need.


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## Flyingsod (Jul 11, 2013)

Semi-Ret Electrician said:


> On a typical conduit to coupling connection after 1 turn CCW very little torque is required to undo the conduit, not so with water pipe.


I think the point micromind is making is that the allowing the conduit to thread all the way to the shallowest grooves makes the whole system more resistant to snapping. In a plumbers fitting where the coupling is tight before its all the way on you have the deeper and therefore weaker parts of the thread un protected by the coupling.
For water tightness a plumbers type fitting may be better but if im using rigid, its because I'm worried about physical damage and I'd prolly rather have the strength.

Fwiw my house predates residential electrification and indoor plumbing. The gas light piping was indeed used as part of the electrification process. Makes me wonder if they electrified or got indoor plumbing first.

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## drewsserviceco (Aug 1, 2014)

Didn't work, boo! I'll try again.


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## drewsserviceco (Aug 1, 2014)




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## drewsserviceco (Aug 1, 2014)




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## RePhase277 (Feb 5, 2008)

Rock knocker said:


> Nice, that's called "attack by innuendo". I wasn't wound up or anything of the sort, I just pointed out why your statement was probably incorrect.
> 
> I hope you get the help that you need.


Uh oh! He's triggered!


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## MechanicalDVR (Dec 29, 2007)

drewsserviceco said:


> View attachment 100049
> 
> 
> View attachment 100057


Don't you just have to love looking at history?


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## drewsserviceco (Aug 1, 2014)

I love the old stuff. Like going back in time, figuring out how the dead men did it. Every hole drilled with a brace and bit...friction tape...slate backboards for knife switches. 

I don't know if I am romanticizing how cool it must've been, like an endless amount of work in a brand new field that was growing and changing with new technology...

They probably felt the way I do now, just another day that I have to go to work.


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## Semi-Ret Electrician (Nov 10, 2011)

Flyingsod said:


> I think the point micromind is making is that the allowing the conduit to thread all the way to the shallowest grooves makes the whole system more resistant to snapping. In a plumbers fitting where the coupling is tight before its all the way on you have the deeper and therefore weaker parts of the thread un protected by the coupling.
> For water tightness a plumbers type fitting may be better but if im using rigid, its because I'm worried about physical damage and I'd prolly rather have the strength.
> 
> Fwiw my house predates residential electrification and indoor plumbing. The gas light piping was indeed used as part of the electrification process. Makes me wonder if they electrified or got indoor plumbing first.
> ...


I believe water/gas piping is a much better/stronger installation than rigid conduit. A tapered thread to tapered thread connection is fully made up with two threads showing. But, if a worn threader is being used, additional torque will improve the connection. 

Once a conduit is made up to a coupling no amount of additional torque will tighten the connection. All the sealing occurs where the coupling buts up against the unthreaded conduit. Most of the conduit threads are not fully engaged.


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## TGGT (Oct 28, 2012)

A tip to those that don't run rigid that often, and to some that do. I see this even among seasoned journeymen and foremen.

*Don't* thread your conduit long when they'll be in a coupling.

There should be about a 1/8'' gap between opposing conduits in the coupling. If you take 2 conduits with factory threads they should become tight before every reaching each other. I've measured about an 1/8'' gap on average for most sizes.

Over long threads leads to conduits butting up against each other, which means one or both conduits will not reach the tapered portion towards the shallow cuts that actually gives the joint rigidity. This also leaves little room to either add one more turn (physically impossible due to conduits butting), or take out a turn (conduit will fit loose and spin freely as soon as you begin to back it off). It also leads to crooked looking joints and/or sagging if there is not a support very close to the coupling.

I usually only thread long when I'm using condulets like LB's, otherwise I measure and match factory thread length when I know I will be mating to another conduit.

May seem like a minor detail, but it can be the difference between a great looking run, or a shoddy looking run.


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## glen1971 (Oct 10, 2012)

TGGT said:


> I usually only thread long when I'm using condulets like LB's, otherwise I measure and match factory thread length when I know I will be mating to another conduit.
> 
> May seem like a minor detail, but it can be the difference between a great looking run, or a shoddy looking run.


I've never heard of doing this. So do you rethread factory ends longer when using Condulet fittings?


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## MechanicalDVR (Dec 29, 2007)

TGGT said:


> A tip to those that don't run rigid that often, and to some that do. I see this even among seasoned journeymen and foremen.
> 
> *Don't* thread your conduit long when they'll be in a coupling.
> 
> ...


I've never run a thread long on purpose but I always stopped the threading for electrical pipe right at the end of the dies as opposed to the face of the die head like one would for gas piping.


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## drewsserviceco (Aug 1, 2014)

I'll run long threads when going into boxes or gear to make the threads inside long enough to get the locknut and bonding bushing on.


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## MechanicalDVR (Dec 29, 2007)

drewsserviceco said:


> I'll run long threads when going into boxes or gear to make the threads inside long enough to get the locknut and bonding bushing on.


If the average thread length is just under 1" long, a box wall thickness is less than 1/8", locknut just over 1/8", and bushing 3/8" you still have close to close to 3/8" more thread to spare. :thumbsup:

It's all good.


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## TGGT (Oct 28, 2012)

glen1971 said:


> I've never heard of doing this. So do you rethread factory ends longer when using Condulet fittings?


I wouldn't go out of my way to do that if they spin on fine but I've rerun factory threads because of poor fitting condulets.


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## Flyingsod (Jul 11, 2013)

glen1971 said:


> I've never heard of doing this. So do you rethread factory ends longer when using Condulet fittings?


How do YOU add a 14" rigid nipple between two boxes that already has a bunch of conduits between them when the customer can't go down? You gotta make long threads on one side...

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## drewsserviceco (Aug 1, 2014)

MechanicalDVR said:


> If the average thread length is just under 1" long, a box wall thickness is less than 1/8", locknut just over 1/8", and bushing 3/8" you still have close to close to 3/8" more thread to spare. :thumbsup:
> 
> 
> 
> It's all good.



I hear what you're saying, but...

The teeth of locknuts make them more than 1/8th

You can't run a locknut all the way down before it bottoms out

And I just like to have some play to work with. 

Plus, I was agreeing with the other guy that does this and illustrating to the poster questioning how/why someone would.


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## MechanicalDVR (Dec 29, 2007)

drewsserviceco said:


> I hear what you're saying, but...
> 
> The teeth of locknuts make them more than 1/8th
> 
> ...


I wasn't being difficult just thinking outloud. The height of a locknut varies with size and brand.


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## drewsserviceco (Aug 1, 2014)

MechanicalDVR said:


> I wasn't being difficult just thinking outloud. The height of a locknut varies with size and brand.



Didn't take it that way at all. Just explaining my POV. 👍🏻


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## Flyingsod (Jul 11, 2013)

Fwiw I routinely have difficulty getting a plastic bushing to stay on because there's not enough room. Especially if I am using a factory end that I was too lazy to chase with the threader.

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## MechanicalDVR (Dec 29, 2007)

I don't understand the problem, if a standard fitting has enough thread to go through a KO and have a locknut and bushing how can a standard pipe thread not do the same?

1" EMT fitting threa dis less than 5/8"








1" std. pipe thread is 7/8"









If a standard thread is 1/4" longer than a standard fitting how could it not be long enough for a locknut and bushing?


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## Flyingsod (Jul 11, 2013)

MechanicalDVR said:


> I don't understand the problem, if a standard fitting has enough thread to go through a KO and have a locknut and bushing how can a standard pipe thread not do the same?
> 
> 1" EMT fitting threa dis less than 5/8"
> 
> ...


Omg... YOU are one of those engineers! I regret to inform you good Sir that the physical realities of this world do not agree with what's written on your pretty paper. Harumph! ;-)

I hear ya though. When everything is clean and straight and you don't have a Dracula locknut there should be plenty of room for a plastic bushing or bonding bushing. I don't get to see text book situations like that too often though. The threads are borked, the box is bent, the lock ring egged, or the stars aren't aligned is how I usually find things.


MechanicalDVR said:


> I don't understand the problem, if a standard fitting has enough thread to go through a KO and have a locknut and bushing how can a standard pipe thread not do the same?
> 
> 1" EMT fitting threa dis less than 5/8"
> 
> ...



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## MechanicalDVR (Dec 29, 2007)

Flyingsod said:


> Omg... YOU are one of those engineers! I regret to inform you good Sir that the physical realities of this world do not agree with what's written on your pretty paper. Harumph! ;-)
> 
> I hear ya though. When everything is clean and straight and you don't have a Dracula locknut there should be plenty of room for a plastic bushing or bonding bushing. I don't get to see text book situations like that too often though. The threads are borked, the box is bent, the lock ring egged, or the stars aren't aligned is how I usually find things.
> 
> ...


Just a realist and I'm not seeing the problem.


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## TGGT (Oct 28, 2012)

Double locknut (top and bottom) you lose about a 1/4". A proper fitting rigid locknut should spin almost all the way down to the last thread. Thickness of material 1/16" to 1/8" on average and we're at about 3/8". 

3/4" factory threads are about 7/8 if I remember correctly, so you should have about a 1/2" of thread left in the box under those conditions. Sometimes it helps to spin the bottom locknut on to find where your "stop" is.


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## drewsserviceco (Aug 1, 2014)

Rarely do I see the outer locknut spin all the way down. Also, most bushings have a lip or extra material before you engage their threads. According to your math, the bushing starts threading on immediately. 

Maybe you guys are better mechanics than me, I'm just saying what I've encountered. I'm also not saying that this is every single time, but it is enough that I rather just run long threads for boxes and cabinets.


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## glen1971 (Oct 10, 2012)

Flyingsod said:


> How do YOU add a 14" rigid nipple between two boxes that already has a bunch of conduits between them when the customer can't go down? You gotta make long threads on one side...
> 
> Sent from my C6725 using Tapatalk


That was not what was being discussed from my quote.. The quote was discussing long threads for condulet fittings.. Not every installation.. I've also see guys make a 1" x 5"(ish) long close nipple (threaded all the way) because they don't know how to make a nipple in the field without a nipple chuck..


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## Flyingsod (Jul 11, 2013)

glen1971 said:


> That was not what was being discussed from my quote.. The quote was discussing long threads for condulet fittings.. Not every installation.. I've also see guys make a 1" x 5"(ish) long close nipple (threaded all the way) because they don't know how to make a nipple in the field without a nipple chuck..


I'm guilty of responding in general not just to your post which I quoted.

You can sometimes thread a short piece by screwing the threaded end into a coupling and making an extender. For me it fails as often as it works. The massive torque from the power pony either jams the piece into the coupling so hard it galls and will never come out or the threads in the coupling buckle and rip.

If you know another way to make short nipples in the field please share. Whether they are long or short threads wouldn't even matter 

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## glen1971 (Oct 10, 2012)

Flyingsod said:


> I'm guilty of responding in general not just to your post which I quoted.
> 
> You can sometimes thread a short piece by screwing the threaded end into a coupling and making an extender. For me it fails as often as it works. The massive torque from the power pony either jams the piece into the coupling so hard it galls and will never come out or the threads in the coupling buckle and rip.
> 
> ...


I've done the coupling trick a few times with limited success too.. 
What I found works best is to thread one end about 5" long, then measure from the solid pipe end of the threads to where a factory length will be on the overthreaded end. Measure the length of your nipple from that point to where you need it.. Cut it.. Put the longer excess threaded pipe into your tristand. When you set it in to clamp it down, make sure you're clear of your mark so that you'll damage threads beyond your mark. Thread the other end.. Cut at your mark.. This will give you tapered threads on both ends of any length of nipple... It's a bit of work, but doesn't take that much more time..

Hope my description isn't too obscure...


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## Flyingsod (Jul 11, 2013)

glen1971 said:


> Hope my description isn't too obscure...



Nope, Crystal clear. It's a nice solution, can't wait to try it. Thanks.



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## TGGT (Oct 28, 2012)

drewsserviceco said:


> Rarely do I see the outer locknut spin all the way down. Also, most bushings have a lip or extra material before you engage their threads. According to your math, the bushing starts threading on immediately.
> 
> Maybe you guys are better mechanics than me, I'm just saying what I've encountered. I'm also not saying that this is every single time, but it is enough that I rather just run long threads for boxes and cabinets.


Not being condescending, are you using rigid locknuts? They spin on much easier and shouldn't take more than 2 channellocks to use up the last few threads. EMT locknuts are not the same. You can usually tell by the stamp on the face.

Rigid locknut:









Generic EMT locknuts that come on connectors usually do not.


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## TGGT (Oct 28, 2012)

Flyingsod said:


> I'm guilty of responding in general not just to your post which I quoted.
> 
> You can sometimes thread a short piece by screwing the threaded end into a coupling and making an extender. For me it fails as often as it works. The massive torque from the power pony either jams the piece into the coupling so hard it galls and will never come out or the threads in the coupling buckle and rip.
> 
> ...


I usually do this on the table threader, have good results the majority of the time down to probably 4'' length max. I've never had the pleasure of using a nipple chuck.


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## drewsserviceco (Aug 1, 2014)

Flyingsod said:


> I'm guilty of responding in general not just to your post which I quoted.
> 
> You can sometimes thread a short piece by screwing the threaded end into a coupling and making an extender. For me it fails as often as it works. The massive torque from the power pony either jams the piece into the coupling so hard it galls and will never come out or the threads in the coupling buckle and rip.
> 
> ...



Have you seen nipple chucks? More used by plumbers, but they allow you to make short nipples with threading machine (400/300/535/1224 etc)


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## MechanicalDVR (Dec 29, 2007)

Why waste your time making short pipe nipples? They are cheap enough to buy in a run close to 8".


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## JRaef (Mar 23, 2009)

Rock knocker said:


> There are two types of American standard pipe threads NPT and NPSM (National Pipe Tapered and National Pipe Straight Mechanical). NPT is required to make a sealed, tight and vibration free connection whether it is for plumbing, keeping conduit as free as possible from rain or maintaining a ground.


Correct info, but the conclusion is flawed. As it was taught to me when I worked at a pipe mill, we are told to thread the conduit with NPT, because it is NOT NPSM. That's because it is NPSM threaded pipe that has restricted uses, such as in scaffolding and such. So by requiring conduit and water pipe to be threaded with NPT, it will not work correctly in things that must use structural pipe that requires NSPM, and vice versa. If you build a scaffold with water pipe or conduit when it was designed around the mechanical strength of the pipe they thread with NPSM, you run a risk of it collapsing on you. So by forcing plumbers and electricians to taper their threads, the scaffolding guys at the job site get a clue that something is wrong when the pipes will not go all the way into the fittings.

In the pipe mill it all started out basically the same, but they were inspected first for small flaws, then given different heat treating processes. Structural pipe was only the least flawed and given the most treatment and strength tested, followed by water pipe which was just pressure tested, then electrical conduit was made from the stuff they couldn't use for the other two, because it was not going to be expected to hold pressure or support structures. So to keep people from using the un-tested pipe for structural use, they required different threading.


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## drewsserviceco (Aug 1, 2014)

MechanicalDVR said:


> Why waste your time making short pipe nipples? They are cheap enough to buy in a run close to 8".



I agree. I have 1/2"-3/4"-1" nipple runs for my plumbing work. 

When I was only a helper working on a co-gen project I got yelled at for wasting time threading both ends of a piece of pipe, versus grabbing a new stick and cutting what I needed and running threads on just one end. 

Funny how quickly cost can change at scale.


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## MechanicalDVR (Dec 29, 2007)

drewsserviceco said:


> I agree. I have 1/2"-3/4"-1" nipple runs for my plumbing work.
> 
> When I was only a helper working on a co-gen project I got yelled at for wasting time threading both ends of a piece of pipe, versus grabbing a new stick and cutting what I needed and running threads on just one end.
> 
> Funny how quickly cost can change at scale.


Every place I have ever worked had milkcrates full of nipples in each pipe size to take out on pipe jobs to avoid trying to make short nipples. The material costs are a fraction of labor to make them.


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## glen1971 (Oct 10, 2012)

MechanicalDVR said:


> Why waste your time making short pipe nipples? They are cheap enough to buy in a run close to 8".


Most of the times I've had to build is when I'm in the middle of no where, and either needed an obscure one (something ending in 8th inch) or one that I didn't have on hand.. I used to carry 1/2" and 3/4" x close, 2", 2 1/2", 3", 4", 5" and 6" with a few of each, and couple of 1" on my truck all the time.. The odd time I'd have 3 1/2" nipples but not too often...


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## MechanicalDVR (Dec 29, 2007)

glen1971 said:


> Most of the times I've had to build is when I'm in the middle of no where, and either needed an obscure one (something ending in 8th inch) or one that I didn't have on hand.. I used to carry 1/2" and 3/4" x close, 2", 2 1/2", 3", 4", 5" and 6" with a few of each, and couple of 1" on my truck all the time.. The odd time I'd have 3 1/2" nipples but not too often...












:whistling2:


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## glen1971 (Oct 10, 2012)

MechanicalDVR said:


> :whistling2:


It looks slick and looks like they go up by 1/2".. Alas it would be a mess in my truck though since I'm on the pavement for about 1/8th of the day.. lol..


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## bill39 (Sep 4, 2009)

glen1971 said:


> That was not what was being discussed from my quote.. The quote was discussing long threads for condulet fittings.. Not every installation.. I've also see guys make a 1" x 5"(ish) long close nipple (threaded all the way) because they don't know how to make a nipple in the field without a nipple chuck..


OK, I'll bite. What's a nipple chuck? That's a new one on me.

I know how to make a factory looking nipple of any length using a Rigid 300-style threader but the term nipple chuck is a new one.


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## MechanicalDVR (Dec 29, 2007)

glen1971 said:


> It looks slick and looks like they go up by 1/2".. Alas it would be a mess in my truck though since I'm on the pavement for about 1/8th of the day.. lol..


Nipple runs always go from close to 6" in 1/2" increments. They come in boxed sets in cardboard. I just always liked the nipple trays for my van.


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## TGGT (Oct 28, 2012)

Rigid locknut on 3/4 factory threads. Spun it on as far as I could go with my hand.










EMT locknut spun as far as I could with my hand, same pipe.


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## MechanicalDVR (Dec 29, 2007)

bill39 said:


> OK, I'll bite. What's a nipple chuck? That's a new one on me.
> 
> I know how to make a factory looking nipple of any length using a Rigid 300-style threader but the term nipple chuck is a new one.


Nowhere near as cool as it sounds, just a pipe chuck that hold sby the last couple threads on a pipe::


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