Any tricks for nipples between existing boxes?

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Demoh

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Pinellas Park, FL
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Field tech
As the title says. Ive done various things from taking a box off the wall & flexing it enough out of the way to add the new nipple, or using those bridgeport mighty-align fittings (my supply houses dont stock) where you slide the pipe in, install the last connector, then slide the pipe out and check to make sure you cant see through the hole, but Ive had some challenging ones lately. It seems every few months I am having to solve this puzzle. How does everybody do it, hopefully without special ordering fittings?

Last one I did the panel was held onto the wall with drywall screws into drywall. No anchors, not into furring strip. I am surprised it wasn't hanging by the conduit before I got it it so it was easy, I just shifted it over 1/2 inch and was able to fit what I needed to fit. (and properly mounting the panel when I was done)

One in particular is 2-1/2 conduit between 4 inchs where there is no way for either box to move. Im thinking chase nipple threaded into a rigid coupling, then a chase nipple but that leaves the challange of not being about to get the locknut on the outside of the box because chase nipples you can never thread the locknut all the way down (like threading the nipple through the locknut)

On the bench a threaded coupling is something like 3-1/4 inches long, so coupling in the middle, locknut facing coupling, locknut facing box, box, chase nipple, repeat for other side comes to 4 inches. chase nipple to threaded nipple has 2+ threads for engagement. Does it sound like this is permissible? Really I am just looking for ideas on how everybody tackles these problems in the future? To date I havent had any problems with inspectors for this type of problem but its always one of my points which causes me undue stress.
 
infinity said:
Use a running thread. You can turn it in from one end all the way through.
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A running thread? is that a thread that isnt tapered like NTP? Thats exactly what ive been looking for but cannot find (nor knew the term for).... searching now.


As for PVC, I do this all the time with LV, This is for applications where I have to use metal.
 
infinity said:
Stick a piece of RMC in a threader and let it go. Or but it at the supply house.
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Found it, pricey and not in stock. Now I have a reason to justify a threader to my boss, all I have is a ratcheting threader Ive used twice.

Thanks. This is up there in the "the answer was in front of my face but cannot see it" lists, mainly because I couldn't for the life of me figure out how to word it in google to get the answer I needed.

Still curious for anybody elses' clever tricks for this.
 
We also use running thread.

May be able to find those inverted type myers hubs or emt fittings where they are flat where they shoulder up to the panel and then the threads come through with the other side of the fitting.

Also Bridgeport makes a "mighty align SLP slip fitting." In this particular case, it looks like you're a little too tight for it to fit though.

Mighty-Align® Steel SLP Slip Connectors

Mighty-Align® SLP Series Slip EMT Connectors. No more wasting time with short conduit cuts. Used to connect EMT to an enclosure in tight or limited access applications. Simply slide fitting onto conduit to the end stop, position EMT, and then slide the co
www.bptfittings.com www.bptfittings.com
 
Demoh said:
Found it, pricey and not in stock. Now I have a reason to justify a threader to my boss, all I have is a ratcheting threader Ive used twice.

Thanks. This is up there in the "the answer was in front of my face but cannot see it" lists, mainly because I couldn't for the life of me figure out how to word it in google to get the answer I needed.

Still curious for anybody elses' clever tricks for this.
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Either find a buddy with a threader or some plumbing supply houses will thread pipe for you. Buy a stick of rigid, cut off a portion of it and thread it from end to end. Then cut your nipple to size as needed.
 
infinity said:
The chase nipple into the threaded coupling is done every day but it is technically not code complaint.
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Interesting. What makes it not compliant? I have also seen bushing threaded into nipple, I see that as not good due to bonding, but nipple into coupler with locknuts?
 
If you're willing to add an EGC and a bonding bushing, don't bother with using four locknuts; omit one of the outer ones. The panel with two will hold the nipple in place rigidly, and you're not using it for bonding.

I once added a genny panel to an existing one in a finished garage. I cut the new panel opening, bored through the stud, installed the second panel, and inserted a nipple, using only two locknuts inside the panels.
 
Todd0x1 said:
Interesting. What makes it not compliant? I have also seen bushing threaded into nipple, I see that as not good due to bonding, but nipple into coupler with locknuts?
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It has to do with the lack of testing of the product combination. Generally, components with straight male threads are not rated to be used in combination with any female threads other than locknuts and bushings. It is expected that the straight male threads of components like chase nipples and EMT connectors are used with locknuts and land on the enclosure wall. Couplings, hubs, threaded conduit bodies, and female threaded entries of boxes are only rated to be used with NPT tapered conduit.
 
This probably isn't the best idea but I have done it

Cut the hole in one panel over sized.

Cover the over sized hole with a 4" square box cover with the correct size hole cut in the middle of it or your conduit

Bolt the box cover to the panel with (4) 1/4-20s

Think of it as screwing a hub to the top of a meter socket
 
2-piece EMT connectors would make it easy to go between two closely spaced boxes.
But unfortunately I haven't seen them in larger than 1 inch.
tpc-100_inuse1.jpg
 
Carultch said:
It has to do with the lack of testing of the product combination. Generally, components with straight male threads are not rated to be used in combination with any female threads other than locknuts and bushings. It is expected that the straight male threads of components like chase nipples and EMT connectors are used with locknuts and land on the enclosure wall. Couplings, hubs, threaded conduit bodies, and female threaded entries of boxes are only rated to be used with NPT tapered conduit.
Click to expand...

Ah ok.

There's threaded hubs sort of like a meyers hub, except the hub that goes on the outside of the box has female threads for the conduit, and on the other side larger female threads. Then there is a male piece that threads into the hub from the inside of the cabinet. These are made for being able to slide a piece of conduit inbetween two existing boxes. Heres the pdf for the OZ-Gedney ones, some other mfgrs make them too. At 2-1/2 these are a little too long for the OP's application.

 
Eddie702 said:
I haven't seen the two piece connectors in a while. I used to like them. If I remember right they may not be UL apprved
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This one says it has UL compliance in the specifications.

1 in. Two Piece EMT Connector | Garvin Industries

Garvin Industries Two Piece Connectors are used when space inside and around the electrical junction box is limited and the installer needs a low profile, less bulky fitting. The split body of this fitting allows quick installation of EMT conduit to elect
www.garvinindustries.com www.garvinindustries.com
 
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