I have a concealed shower valve and want to fit a shower outlet elbow about 15cm beneath the valve, leading to the hose etc.
I can't figure how to fit the elbow. It has a female 0.5" BSP parallel thread and slight chamfer to the entry of that thread, indicating to me that it would like to see an o-ring.
The problem I have is that it all seems too precise. I will have to know EXACTLY the level of my tiled surface so that when the o-ring is properly compressed the elbow, and its chromed flange washer, will be comfortably firm against the tiled wall.
Am I doing this wrongly? Should I be just bodging it with some setting plumbers goop and not using an o-ring at all?