Hurray, I made a start! I spent quite a while ditzing around, driving back to get the shed key I forgot, swapping the three jaw chuck back in, dropping the speed to 400 rpm, but finally chucked the brass part and faced and turned it to 27mm. Next I need to center drill it and then part it off (always exciting).
Not a huge amount of progress, but a start nonetheless!
One trick I have learned is to use a block of wood between the carriage and the tailstock, with the tailstock locked down to avoid the carriage moving while I am facing or turning (since no one is holding the handwheel).