3/4" steel conduit

[TedBk]

I am trying to find 3/4"inch brass bushs do they still exist?

 

[delmel]

you can get a 3/4 to 20mm adaptor. I have never in years come across a 3/4 male brass bush. I have known people ask for a 3/4 brass bush but actually mean a 20mm which is available.

 

[333rocky333]

Unlikely nowadays, but if not using it for Earth continuity, you could likely fit a 20mm socket over the thread and use a 20mm bush, once the box is on then its unlikely the socket will move.

 

[TedBk]

you can get a 3/4 to 20mm adaptor

I have a few of those, which I can use in few instances.

but if not using it for Earth continuity

Yes, the conduit is being used as the CPC. However some of the light switches don't have a bush. It is hard to tell if this was by "design" because the back box is not in contact with conduit, by a few mm. However the metal back box has plastic screw holes, so the face place is insulated, and the switch is double insulated as a result.

I can continue with plastic face plates etc, if I can get brass bushs of the correct size I can bring the CPC to the back box and the face plate, which I would prefer. In this instance there is not enough room for an adapter.

 

[SUNRAY]

I haven't tried it myself [and to be honest I dont see how it could work] but I've seen suggestions that simply recutting the thread on a 20mm bush with a 3/4" die can work.

I've also heard of wrapping wire onto the 34" conduit thread then use a 20mm bush. again not something I've tried.

My thoughts are running now. The 2 threads are nearly similar and a 20mm bush almost feels like it's screwing onto a tube [I know as I've tried mixing]. So how about drilling and tapping a 20mm coupler and fitting a couple of grub screws, ti tighten against the 3/4" thread.

It's been a long time since I've been in this situation and I'm starting to doubt which tube diameter is the bigger 20mm or 3/4"

 

[SUNRAY]

They had to be there somewhere:

http://brass-bushings.brass-nuts-inserts.com/brass-male-female-conduit-bushes.htm