RMC service mast

[iwire]

I would cite 230.28. Threading RMC removes about 50% of the metal at the thread.

I think he was asking about the connector / hub issue.

 

[infinity]

I think he was asking about the connector / hub issue.

Opps, I missed that one completely. :roll:

 

[stickboy1375]

I think he was asking about the connector / hub issue.

You would be correct.

 

[JDB3]

Joe

Joe

Personally, I use IMC on risers through the roof. Higher tensile strength than RMC (except where one utility company "requires" RMC). But yes, I use IMC all the way (more / better support).

 

[stickboy1375]

http://www.ecmag.com/?articleID=11585&fa=article

This helped answer a lot of questions.

 

[hurk27]

Here we used to keep 20' sticks of 2" RMC in stock for runs like this, but we never put the cut end at the meter as all our weather heads are clamp on so no threads needed at it, I do agree that the installation in the OP photo needs to be guyed off.

We had a house that caught fire when the SEC's shorted out leaving one of the hots welded to the riser but the neutral burned/broke free, this put all the fault current on the GEC that went to the water line that was run through the basement floor joist, I guess it turned into a heating element trying to carry the unprotected fault current back to the source through the house next door's GEC from it's water pipe bond which received smoke damage and all the green insulation on its GEC was burned off, but was shorter run to the water line.
Also the cable TV drop to the house melted and fell to the ground, lucky that it only damaged the floor joist and didn't get to far as the FD got there fast.

 

[sd4524]

Funny, I was picking up the parts for the job yesterday and I hadn't read the responses to my emt to ridgid transition comment. I ended up getting 2 sticks of ridgid and the threadless coupling. Just made way more sense as I was thinking about it. Those threadless couplings are pricey but worth it imo.

 

[stickboy1375]

Funny, I was picking up the parts for the job yesterday and I hadn't read the responses to my emt to ridgid transition comment. I ended up getting 2 sticks of ridgid and the threadless coupling. Just made way more sense as I was thinking about it. Those threadless couplings are pricey but worth it imo.

I would have used a thread less connector, but thats just me.

 

[sd4524]

Are all ridgid threadless couplings raintight?

 

[kwired]

How about getting one piece cut in half, find a place to thread the cut ends, some HD have threaders I think, when you are on site use the full piece as the upper piece, cut to needed length and use a clamp on weatherhead on the cut end. Your remaining 5 foot piece threaded on both ends can be used next time you do a similar install.

I myself have a couple regular customers I can borrow power threading equipment from when needed. Have my own hand threader for 1/2 - 1"

 

[hurk27]

How about getting one piece cut in half, find a place to thread the cut ends, some HD have threaders I think, when you are on site use the full piece as the upper piece, cut to needed length and use a clamp on weatherhead on the cut end. Your remaining 5 foot piece threaded on both ends can be used next time you do a similar install.

I myself have a couple regular customers I can borrow power threading equipment from when needed. Have my own hand threader for 1/2 - 1"

Here our ACE Hardware store threads pipe, but I do like the idea of using the thread-less over a threaded coupling as it would be much stronger connection if they are of the malleable iron type like I have used, a threaded connection is very weak from the threads. now if we could only get the rain tight in our area:rant:

 

[hurk27]

I don't know what I was thinking in post 26 about putting the un-threaded end up at the weather head, as we only do that when we need to cut a single stick in shorter risers, and you couldnt do that when you have to extend the riser as in the photo, which is what I think they did as the WH is a clamp on.

 

[cowboyjwc]

Here the utility wouldn't connect to it if it had a coupling above the roof.

 

[Cow]

The local irrigation place here can thread pipe here too. That's how we used to get our 3" and 4" done before we picked up a big threader.

 

[paul]

WA wouldn't approve this install. We have to abide by the following:

Utilization of couplings for a mast is permitted only below the point the mast is braced, secured, or supported. There must be a minimum of two means of support above any couplings used. A properly installed cable or stiff leg type support qualifies as one of the two required means of support.

 

[renosteinke]

I've never needed more than a single stick of pipe for a mast - count my blessings - yet my "service change" kit includes a cheap 2" thread die.

This is because the pipe always seems to have far too much zinc on the coupling-free end of the pipe; so much that it interferes with the entry into the hub. Or, perhaps, the threads got damaged. In either case, the die is plenty good enough to clean up the threads.