Conduit System Components - Help!

I have a weatherproof electrical box that I want to mount on a fence. And I have a weatherproof electrical box that I want to mount on a post about 6 feet away. I have a trench dug between them already that is about 18 inches deep and the earth is soft and easy to dig.

The electrical boxes have 3/4 pipe thread. I have 3/4 PVC conduit for the underground portion. How do I connect the conduit coming up from the ground to the two electrical boxes? Since they have threads, something needs to turn, and the boxes can't since they are blocked by their mounting surfaces. I haven't seen fittings that are pipe thread on one end and PVC compression on the other. So I think I need to put the threaded components into each electrical box, then glue the two halves of the system together at a point that is away from the electrical box. Is that the process or am I missing something? This of course can never be disassembled. A list of components, starting at one electrical box, would be appreciated.

 

You would screw 3/4" PVC connectors into the box(es) first. Then the pipe would be glued into the fittings. No need to have to turn the box(es).

 

In addition to PJmax's answer, put some sort of thread sealant (same ones you use for plumbing) for additional water proofing. Both caps and male adapters.
I found rain water sometimes leaks in from the thread.

 

Thanks.

How do I connect 3/4 EMT to the 3/4 pipe thread on the weathertight box?

 

Use a rain-tight threaded adapter.

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If the fittings are screwed into the bottom of the box then no sealant is required. It's actually better to allow any lost water to be able to find it's way out.

 

Are you using EMT or PVC??????????

 

EMT is not for burial. It would rust out in a few years.

 

I read it as EMT along the fence then PVC to the receptacle on the post.

 

I read it to mean the conduit will be buried 18 inches deep.

Don't use EMT underground.