Harry Bloomfield wrote:
lovezoo presented the following explanation :
I don't want to use squirty expanding foam, I want a nice smooth
cement finish to paint over.

3 parts sand to 1 part cement? Just cement?

Surely, with the movement and vibration, it will just fall off?

Correct.

Only way to bond cement to steel is to cast it round something like a
load of screws or nails.