Thanks for all the info. When you say get back to 1/2" do you mean just sand /rub it back until it reduces to that size ?
It's so annoying that nothing will fit to it, so hopefully going with the advice on here something will work.
I'm new here, so hello to everyone.
We are in the process of removing our old 1970's bathroom suite and have come up against a bit of a headache. After removing the old plastic cistern, we have realised that the cold water feed pipe, along with the rest of the cold water pipes in the bathroom...