Installing a Smaller EMT Conduit Into a Set-Screw Hub of a Larger Size

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I have it! Wrap a strip of metal around the end of the 3/4" EMT until it will barely fit into the T; then tighten the setscrews.
 
Use a short piece of conduit with a connector. Install theaded coupling.Put reducing bushing in coupling.
 
Serious response: get a reducing bushing, either 1-1/4-to-3/4 or 1-1/2-to-3/4, whichever has a large-enough OD, and grind the outer threads off along with enough material to end up with a smooth puck that will just drop in the T-condulet, tighten screws.


Fun response:

Oldmaster2 said:
Use a short piece of conduit with a connector. Install theaded coupling.Put reducing bushing in coupling.
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"Why don't they make something that will work?"
 
LarryFine said:
Serious response: get a reducing bushing, either 1-1/4-to-3/4 or 1-1/2-to-3/4, whichever has a large-enough OD, and grind the outer threads off along with enough material to end up with a smooth puck that will just drop in the T-condulet, tighten screws.
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I was thinking along similar lines, machining something that will fit, could turn the reducing bushing down in a lathe I guess.

1-1/4 bushing should be larger OD than OD of 1-1/4 EMT, once threads are cut off it might be close to same size.
 
kwired said:
Low power control conductors?
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The supplier of the equipment provided a specification that reads in part: '...each unit requires a dedicated ground back to the facility load center ground buss'. There would be possible warranty issues if I don't comply. I REALLY hate it when a specifying engineer writes specifications without verified justification. I suspect he pulled off of a hospital general spec for an MRI installation or some other sensitive equipment.
 
britcollector said:
The supplier of the equipment provided a specification that reads in part: '...each unit requires a dedicated ground back to the facility load center ground buss'. There would be possible warranty issues if I don't comply. I REALLY hate it when a specifying engineer writes specifications without verified justification. I suspect he pulled off of a hospital general spec for an MRI installation or some other sensitive equipment.
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I might have misunderstood what you have. Apparently is the power circuits to multiple CNC machines. I was thinking wiring within a machine.

That said if using a conduit body instead of pull/junction boxes you might be pulling separate EGC's anyhow because you might not have room to splice them in the conduit body(ies).
 
augie47 said:
I like K-wired's idea,.,,,,, short section of 1-1/4 conduit to an adapter (EMT to Female PT if available, or EMT to Male and a coupling) then install your bushing in that fitting.
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EMT to rigid coupling.jpg
I've never seen a EMT to rigid coupling but I guess they are made. Pretty spendy, about $20 per fitting for 1-1/4" from Garvin. Might be more cost effect to go with the male EMT connector to rigid coupling with a reducing bushing in it. Or by the time you're done messing around it might be more cost effective to just replace all the conduit bodies with ones with threaded hubs.
 
A coupling for 1" GRC has a nominal O.D. of 1.53", and the O.D. of 1-1/4" EMT is 1.510".
So if the "T" condulet openings have at least 0.020" clearance for the EMT then a 1" GRC coupling might fit into them. Then you could insert a 1" to 3/4" reducing bushing inside the GRC coupling. You might have to scrape some paint out of the condulet opening, or worst case remove a little metal from the coupling's O.D.

Galvanized Rigid Conduit (GRC) Couplings - Allied Tube & Conduit | Electrical Conduit

Rigid steel couplings are interchangeable with IMC and Rigid (GRC) Steel Conduits and Super Kwik-Couple Conduits.
www.alliedeg.us www.alliedeg.us
 
480sparky said:
Buy a metal lathe and a block of steel. Mill a custom adapter.
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I have a lathe and could turn custom spacers, but I just don't have the time to make 15 of them...and I don't have the room to stack up various fittings to make the size reduction. Anyway, I've ordered threaded type-T conduit bodies and reducer bushings, and will sell the screw type ones I already have for what I paid ($6 each w/covers). Using threaded bodies is the cleanest, easiest way to do it. I was just trying to save a few $.

Thanks everyone for all your great suggestions. I do appreciate it!

Be safe!
 
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britcollector said:
I have a lathe and could turn custom spacers, but I just don't have the time to make 15 of them...and I don't have the room to stack up various fittings to make the size reduction. Anyway, I've ordered threaded type-T conduit bodies and reducer bushings, and will sell the screw type ones I already have for what I paid ($6 each w/covers). Using threaded bodies is the cleanest, easiest way to do it. I was just trying to save a few $.

Thanks everyone for all your great suggestions. I do appreciate it!

Be safe!
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Sometimes saving a dollar or two cost you ten to twenty more in some other way.
 
While there are creative ways to solve this one, be mindful of approved uses of fittings, connectors and such and especially of home-made parts. As kwired said, sometimes it's more cost effective to spend a bit more upfront.
 
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