I machined mine in the lathe
thanks ordered a couple but expensive. I tried on a bench grinder but as you know its impossible to grind flat. Yep facing on a lathe would be a piece of piss Matt but need to get this project completed soon as my time will be limited with this new job. Hopefully Greg will do me proud and get the stuff to me this week.
Thanks for the suggestions guys, I will try and get the old cores machined later for quick change over spares.