Running RMC, techniques

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sw_ross

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Looking at a job that looks like it would require running some RMC.
I'm just a small one man operation so I don't own mechanical benders and threaders, etc, and can't justify buying the equipment just to do this job.

I've priced out pre-made threaded 90's and 45's as well as 10' sticks, but got visualizing the route in my head and was thinking I'll probably need to cut/shorten a piece of the RMC along the route.

Without a threader how would I join up this shorter piece?
Is there a Union of some sort that can be used to accomplish this joint?

This conduit would be for service conductors feeding the meter/Main.

Thanks!
 
Since you won't be cutting and threading the RMC you can use either threadless connectors or couplings.

compression-rigid-couplings-for-threadless-rigid-conduit.jpg
 
use the compression fittings or find a threader to rent, if laying it out carefully and only need a piece or two threaded take those pieces to someone that can thread them.

Harbor Freight has a 3/8-2 inch hand threader set for only $75. Might be worth it for just one job, probably won't last if you use it frequently.

Small sizes you can bend with hand benders - use next larger EMT size bender for RMc/IMC. Be prepared for stubs to not come out to same accuracy as they do for EMT, but if you use firm foot pressure while bending they will still be consistant. 3/4 EMT bender - deduct 6 inches for a stub for your mark - I think mine I marked it - use 6-3/8 for bending (1/2") RMC. I do bend 1/2 and 3/4 with hand bender fairly often.

I have up to 1" threader handle and dies that I bought at auction for maybe only $30 or so about 20 years ago. Rigid brand. Only replaced cutting dies on one of them since I have had it.
 
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Compression coupling.

Compression coupling.

So it looks like an EMT compression fitting ? I'll have to check it out with the supply house.
 
sw_ross said:
So it looks like an EMT compression fitting ? I'll have to check it out with the supply house.
Click to expand...
Same design but not same dimension - it is made to fit RMC/IMC.

Probably easy to find in stock for 1/2 and 3/4 but not so much for 2 inch. Probably kind of pricey for 2 inch as well I would guess.
 
sw_ross said:
So it looks like an EMT compression fitting ? I'll have to check it out with the supply house.
Click to expand...

They also make set screw types. Above 2" many set screw EMT connectors and coupling are also listed for RMC because the outside diameter are roughly the same for both types of raceways.
 
Also, some supply houses have demos and rentals. If it is only a a piece or two, you may get to use a threader or possibly they will thread for a small nominal fee. If you are a good customer, maybe nada. I have went this route in a pinch.
 
jumper said:
Also, some supply houses have demos and rentals. If it is only a a piece or two, you may get to use a threader or possibly they will thread for a small nominal fee. If you are a good customer, maybe nada. I have went this route in a pinch.
Click to expand...

Somebody recently mentioned going to HD or Lowes and getting a stick of EMT, grabbing a bender and making needed bends, putting bender back on shelf and proceeding to cashier to pay for bent piece of raceway.
 
If you are a union member, you can usually use the equipment at the apprenticeship training center.

If you are friends with other ECs, you can usually borrow equipment from them.
 
The idea is that you can bend the conduit and still be able to turn the coupling without turning the conduit. Big improvement when running large conduit with big elbows.
 
kwired said:
Somebody recently mentioned going to HD or Lowes and getting a stick of EMT, grabbing a bender and making needed bends, putting bender back on shelf and proceeding to cashier to pay for bent piece of raceway.
Click to expand...

That was me. I'd be embarrassed to say how many times I had to do it because my bender wasn't on the job with me, but hey, I was headed to the store for pipe anyway. Small jobs, too, so bend location wasn't critical or I had the measurement with me. Heck, most of the time I remembered to bring my tape measure with me into the store. Guess what I did if I forgot? :p

They do threading at these stores, but it's done in the plumbing section, and you probably have no choice but to get tapered threads.
 
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