Hi,
Thank you, Sam, John & Stephen for your interesting replies. I wondered if they might have glued them to prevent them from squealing? I was wondering how the people that rewind them would attempt to separate the core without damage?
I've not tried heat on this one yet, but the hotplate idea, whilst a bit scary seems like it might be the best way to go. I do have access to non-diy paint stripper which is quite potent, but getting it down the tiny gap between the former and the core would be difficult.
It certainly doesn't want to fall apart
Cheers
Nick